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Preventive treatment delays first seizure onset in tuberous sclerosis complex
according to research presented at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year. This treatment strategy reduces the risk and severity of epilepsy, said the investigators.
As much as 90% of patients with TSC have epilepsy. Seizures generally start during infancy and are often resistant to medication. Clinicians are increasingly able to diagnose TSC prenatally, thus creating an opportunity for pursuing preventive strategies.
In the multicenter EPISTOP trial, Katarzyna Kotulska, MD, head of neurology and epileptology at Children’s Memorial Health Institute in Warsaw, and colleagues compared the efficacy and safety of preventive vigabatrin treatment with those of conventional vigabatrin treatment in infants with TSC. The researchers followed 94 infants with TSC and without a history of seizures with monthly video EEG. Conventional treatment was initiated after the first electrographic or clinical seizure, and preventive treatment was administered when epileptiform discharges were visible on EEG but before the first seizure.
Six sites randomly assigned patients to treatment in a equal groups in a randomized, controlled trial. At four other sites, treatment allocation was fixed in an open-label trial. All patients were followed until age 2 years. The study’s primary endpoint was the time to first clinical seizure.
A total of 53 patients participated in the randomized, controlled trial, and 41 participated in the open-label study; 79 patients completed the study. Of this group, 25 received preventive treatment, 25 received conventional treatment, and 22 patients had seizures before epileptiform activity was detected on EEG. Seven patients had neither seizures nor abnormal EEG.
The time to first clinical seizure was significantly longer in patients who received preventive treatment, compared with those who received conventional treatment. In the randomized, controlled trial, time to first seizure was 364 days in the preventive treatment group and 124 days in the conventional treatment group. In the open-label trial, time to first seizure was 426 days in the preventive treatment group and 106 days in the conventional treatment group.
A pooled analysis indicated that, at 24 months, preventive treatment significantly reduced the risk of clinical seizures (odds ratio, 0.21), drug-resistant epilepsy (OR, 0.23), and infantile spasms (OR, 0). The investigators did not record any adverse events related to preventive treatment.
The study was funded by the 7th Framework Program of the European Union. Dr. Kotulska did not report any disclosures.
SOURCE: Kotulska K et al. CNS-ICNA 2020, Abstract PL13.
according to research presented at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year. This treatment strategy reduces the risk and severity of epilepsy, said the investigators.
As much as 90% of patients with TSC have epilepsy. Seizures generally start during infancy and are often resistant to medication. Clinicians are increasingly able to diagnose TSC prenatally, thus creating an opportunity for pursuing preventive strategies.
In the multicenter EPISTOP trial, Katarzyna Kotulska, MD, head of neurology and epileptology at Children’s Memorial Health Institute in Warsaw, and colleagues compared the efficacy and safety of preventive vigabatrin treatment with those of conventional vigabatrin treatment in infants with TSC. The researchers followed 94 infants with TSC and without a history of seizures with monthly video EEG. Conventional treatment was initiated after the first electrographic or clinical seizure, and preventive treatment was administered when epileptiform discharges were visible on EEG but before the first seizure.
Six sites randomly assigned patients to treatment in a equal groups in a randomized, controlled trial. At four other sites, treatment allocation was fixed in an open-label trial. All patients were followed until age 2 years. The study’s primary endpoint was the time to first clinical seizure.
A total of 53 patients participated in the randomized, controlled trial, and 41 participated in the open-label study; 79 patients completed the study. Of this group, 25 received preventive treatment, 25 received conventional treatment, and 22 patients had seizures before epileptiform activity was detected on EEG. Seven patients had neither seizures nor abnormal EEG.
The time to first clinical seizure was significantly longer in patients who received preventive treatment, compared with those who received conventional treatment. In the randomized, controlled trial, time to first seizure was 364 days in the preventive treatment group and 124 days in the conventional treatment group. In the open-label trial, time to first seizure was 426 days in the preventive treatment group and 106 days in the conventional treatment group.
A pooled analysis indicated that, at 24 months, preventive treatment significantly reduced the risk of clinical seizures (odds ratio, 0.21), drug-resistant epilepsy (OR, 0.23), and infantile spasms (OR, 0). The investigators did not record any adverse events related to preventive treatment.
The study was funded by the 7th Framework Program of the European Union. Dr. Kotulska did not report any disclosures.
SOURCE: Kotulska K et al. CNS-ICNA 2020, Abstract PL13.
according to research presented at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year. This treatment strategy reduces the risk and severity of epilepsy, said the investigators.
As much as 90% of patients with TSC have epilepsy. Seizures generally start during infancy and are often resistant to medication. Clinicians are increasingly able to diagnose TSC prenatally, thus creating an opportunity for pursuing preventive strategies.
In the multicenter EPISTOP trial, Katarzyna Kotulska, MD, head of neurology and epileptology at Children’s Memorial Health Institute in Warsaw, and colleagues compared the efficacy and safety of preventive vigabatrin treatment with those of conventional vigabatrin treatment in infants with TSC. The researchers followed 94 infants with TSC and without a history of seizures with monthly video EEG. Conventional treatment was initiated after the first electrographic or clinical seizure, and preventive treatment was administered when epileptiform discharges were visible on EEG but before the first seizure.
Six sites randomly assigned patients to treatment in a equal groups in a randomized, controlled trial. At four other sites, treatment allocation was fixed in an open-label trial. All patients were followed until age 2 years. The study’s primary endpoint was the time to first clinical seizure.
A total of 53 patients participated in the randomized, controlled trial, and 41 participated in the open-label study; 79 patients completed the study. Of this group, 25 received preventive treatment, 25 received conventional treatment, and 22 patients had seizures before epileptiform activity was detected on EEG. Seven patients had neither seizures nor abnormal EEG.
The time to first clinical seizure was significantly longer in patients who received preventive treatment, compared with those who received conventional treatment. In the randomized, controlled trial, time to first seizure was 364 days in the preventive treatment group and 124 days in the conventional treatment group. In the open-label trial, time to first seizure was 426 days in the preventive treatment group and 106 days in the conventional treatment group.
A pooled analysis indicated that, at 24 months, preventive treatment significantly reduced the risk of clinical seizures (odds ratio, 0.21), drug-resistant epilepsy (OR, 0.23), and infantile spasms (OR, 0). The investigators did not record any adverse events related to preventive treatment.
The study was funded by the 7th Framework Program of the European Union. Dr. Kotulska did not report any disclosures.
SOURCE: Kotulska K et al. CNS-ICNA 2020, Abstract PL13.
FROM CNS-ICNA 2020
Comorbidity burden is greater among children with tics than children with stereotypies
, according to an analysis presented at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year. The former also are younger at their first visit than are the latter. Compared with children with tics, children with stereotypies also have fewer comorbidities and receive fewer recommendations for interventions. This difference between groups may not merely reflect the younger age at presentation of children with stereotypies (e.g., at an age before a comorbidity is manifest). “At least in our population, it does seem to reflect an overall lower burden of comorbidities,” said Shannon Dean, MD, PhD, assistant professor of neurology at the Kennedy Krieger Institute of Johns Hopkins University in Baltimore.
Common pediatric movement disorders
Tics (i.e., short-lasting, sudden, repetitive movements) and stereotypies (i.e., rhythmic, fixed, deliberate, but purposeless movements) are common pediatric movement disorders with favorable prognoses. The disorders share several comorbidities, the most common of which are ADHD, anxiety, and obsessive-compulsive disorder (OCD). Dr. Dean and colleagues examined differences in comorbidity burden, resource use, and need for intervention between children with tics and those with stereotypies.
The investigators performed a retrospective chart review and identified 63 children diagnosed with stereotypies. They matched each of these children, by age when possible, with a child first diagnosed with a chronic or provisional tic disorder during the same year. All patients presented to the University of Rochester (N.Y.) Child Neurology Clinic between 2003 and 2016. Dr. Dean and colleagues excluded children with diagnoses for which stereotypies are considered a secondary feature (e.g., autism, intellectual disability, and blindness). They also excluded children who had tics and stereotypies.
The researchers examined the groups’ total number of visits, comorbidities, and recommended interventions. They also analyzed data from a follow-up survey that were available for 20 of the 63 patients with stereotypies. They tested continuous or discrete variables for normal distribution and used T tests or Mann–Whitney U as appropriate. To analyze categorical data, they used chi squared or Fisher’s exact test for groups smaller than five.
Differing rates of intervention
Children with stereotypies were younger at first visit (mean age, 5.6 years vs. 7.1 years) and at last visit (mean age, 6.5 years vs. 9.8 years) and had fewer total visits (1.8 vs. 4.5), compared with children with tics.
The three most common comorbidities in the population were more prevalent among patients with tics than among patients with stereotypies. The prevalence of ADHD was 27% among patients with stereotypies and 48% among patients with tics. The prevalence of OCD was 8% among children with stereotypies and 41% among children with tics. The prevalence of anxiety was 21% among children with stereotypies and 63% among children with tics. Children with stereotypies also had fewer neuropsychiatric comorbidities overall than did children with tics (0.7 per patient versus 1.9 per patient).
The clinicians had recommended at least one medication for tics in 22% of the children with tics. No medication is available for children with stereotypies. The clinicians recommended behavioral therapy for 13% of the children with tics, but for none of the children with stereotypies, “because none of them had functional impairment that would warrant intervention,” said Dr. Dean. The clinicians also made more recommendations for pharmaceutical and behavioral treatments for comorbidities in patients with tics than in patients with stereotypies.
When the investigators examined the follow-up survey data, they found that patients with stereotypies were older at last contact than patients with tics. Last contact was defined as the time of the survey for patients with stereotypies and the time of the last clinic visit for patients with tics. When Dr. Dean and colleagues examined the three most common comorbidities, however, they again found that the burden was greater among patients with tics (1.5 per patient) than among patients with stereotypies (0.8 per patient).
The study was funded by the T32 Experimental Therapeutics Training Grant from the University of Rochester, N.Y. Dr. Dean did not report any disclosures.
SOURCE: Dean S et al. CNS-ICNA 2020. Abstract PL52.
, according to an analysis presented at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year. The former also are younger at their first visit than are the latter. Compared with children with tics, children with stereotypies also have fewer comorbidities and receive fewer recommendations for interventions. This difference between groups may not merely reflect the younger age at presentation of children with stereotypies (e.g., at an age before a comorbidity is manifest). “At least in our population, it does seem to reflect an overall lower burden of comorbidities,” said Shannon Dean, MD, PhD, assistant professor of neurology at the Kennedy Krieger Institute of Johns Hopkins University in Baltimore.
Common pediatric movement disorders
Tics (i.e., short-lasting, sudden, repetitive movements) and stereotypies (i.e., rhythmic, fixed, deliberate, but purposeless movements) are common pediatric movement disorders with favorable prognoses. The disorders share several comorbidities, the most common of which are ADHD, anxiety, and obsessive-compulsive disorder (OCD). Dr. Dean and colleagues examined differences in comorbidity burden, resource use, and need for intervention between children with tics and those with stereotypies.
The investigators performed a retrospective chart review and identified 63 children diagnosed with stereotypies. They matched each of these children, by age when possible, with a child first diagnosed with a chronic or provisional tic disorder during the same year. All patients presented to the University of Rochester (N.Y.) Child Neurology Clinic between 2003 and 2016. Dr. Dean and colleagues excluded children with diagnoses for which stereotypies are considered a secondary feature (e.g., autism, intellectual disability, and blindness). They also excluded children who had tics and stereotypies.
The researchers examined the groups’ total number of visits, comorbidities, and recommended interventions. They also analyzed data from a follow-up survey that were available for 20 of the 63 patients with stereotypies. They tested continuous or discrete variables for normal distribution and used T tests or Mann–Whitney U as appropriate. To analyze categorical data, they used chi squared or Fisher’s exact test for groups smaller than five.
Differing rates of intervention
Children with stereotypies were younger at first visit (mean age, 5.6 years vs. 7.1 years) and at last visit (mean age, 6.5 years vs. 9.8 years) and had fewer total visits (1.8 vs. 4.5), compared with children with tics.
The three most common comorbidities in the population were more prevalent among patients with tics than among patients with stereotypies. The prevalence of ADHD was 27% among patients with stereotypies and 48% among patients with tics. The prevalence of OCD was 8% among children with stereotypies and 41% among children with tics. The prevalence of anxiety was 21% among children with stereotypies and 63% among children with tics. Children with stereotypies also had fewer neuropsychiatric comorbidities overall than did children with tics (0.7 per patient versus 1.9 per patient).
The clinicians had recommended at least one medication for tics in 22% of the children with tics. No medication is available for children with stereotypies. The clinicians recommended behavioral therapy for 13% of the children with tics, but for none of the children with stereotypies, “because none of them had functional impairment that would warrant intervention,” said Dr. Dean. The clinicians also made more recommendations for pharmaceutical and behavioral treatments for comorbidities in patients with tics than in patients with stereotypies.
When the investigators examined the follow-up survey data, they found that patients with stereotypies were older at last contact than patients with tics. Last contact was defined as the time of the survey for patients with stereotypies and the time of the last clinic visit for patients with tics. When Dr. Dean and colleagues examined the three most common comorbidities, however, they again found that the burden was greater among patients with tics (1.5 per patient) than among patients with stereotypies (0.8 per patient).
The study was funded by the T32 Experimental Therapeutics Training Grant from the University of Rochester, N.Y. Dr. Dean did not report any disclosures.
SOURCE: Dean S et al. CNS-ICNA 2020. Abstract PL52.
, according to an analysis presented at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year. The former also are younger at their first visit than are the latter. Compared with children with tics, children with stereotypies also have fewer comorbidities and receive fewer recommendations for interventions. This difference between groups may not merely reflect the younger age at presentation of children with stereotypies (e.g., at an age before a comorbidity is manifest). “At least in our population, it does seem to reflect an overall lower burden of comorbidities,” said Shannon Dean, MD, PhD, assistant professor of neurology at the Kennedy Krieger Institute of Johns Hopkins University in Baltimore.
Common pediatric movement disorders
Tics (i.e., short-lasting, sudden, repetitive movements) and stereotypies (i.e., rhythmic, fixed, deliberate, but purposeless movements) are common pediatric movement disorders with favorable prognoses. The disorders share several comorbidities, the most common of which are ADHD, anxiety, and obsessive-compulsive disorder (OCD). Dr. Dean and colleagues examined differences in comorbidity burden, resource use, and need for intervention between children with tics and those with stereotypies.
The investigators performed a retrospective chart review and identified 63 children diagnosed with stereotypies. They matched each of these children, by age when possible, with a child first diagnosed with a chronic or provisional tic disorder during the same year. All patients presented to the University of Rochester (N.Y.) Child Neurology Clinic between 2003 and 2016. Dr. Dean and colleagues excluded children with diagnoses for which stereotypies are considered a secondary feature (e.g., autism, intellectual disability, and blindness). They also excluded children who had tics and stereotypies.
The researchers examined the groups’ total number of visits, comorbidities, and recommended interventions. They also analyzed data from a follow-up survey that were available for 20 of the 63 patients with stereotypies. They tested continuous or discrete variables for normal distribution and used T tests or Mann–Whitney U as appropriate. To analyze categorical data, they used chi squared or Fisher’s exact test for groups smaller than five.
Differing rates of intervention
Children with stereotypies were younger at first visit (mean age, 5.6 years vs. 7.1 years) and at last visit (mean age, 6.5 years vs. 9.8 years) and had fewer total visits (1.8 vs. 4.5), compared with children with tics.
The three most common comorbidities in the population were more prevalent among patients with tics than among patients with stereotypies. The prevalence of ADHD was 27% among patients with stereotypies and 48% among patients with tics. The prevalence of OCD was 8% among children with stereotypies and 41% among children with tics. The prevalence of anxiety was 21% among children with stereotypies and 63% among children with tics. Children with stereotypies also had fewer neuropsychiatric comorbidities overall than did children with tics (0.7 per patient versus 1.9 per patient).
The clinicians had recommended at least one medication for tics in 22% of the children with tics. No medication is available for children with stereotypies. The clinicians recommended behavioral therapy for 13% of the children with tics, but for none of the children with stereotypies, “because none of them had functional impairment that would warrant intervention,” said Dr. Dean. The clinicians also made more recommendations for pharmaceutical and behavioral treatments for comorbidities in patients with tics than in patients with stereotypies.
When the investigators examined the follow-up survey data, they found that patients with stereotypies were older at last contact than patients with tics. Last contact was defined as the time of the survey for patients with stereotypies and the time of the last clinic visit for patients with tics. When Dr. Dean and colleagues examined the three most common comorbidities, however, they again found that the burden was greater among patients with tics (1.5 per patient) than among patients with stereotypies (0.8 per patient).
The study was funded by the T32 Experimental Therapeutics Training Grant from the University of Rochester, N.Y. Dr. Dean did not report any disclosures.
SOURCE: Dean S et al. CNS-ICNA 2020. Abstract PL52.
FROM CNS-ICNA 2020
NMOSD challenges in children
, but have led to some uncertainty and confusion as well.
At the2020 CNS-ICNA Conjoint Meeting, held virtually this year, presenters discussed some of the challenges of differential diagnosis and treatment choice in pediatric NMOSD, which is easily confused with multiple sclerosis.
NMOSD used to be considered a monophasic disease restricted to the optic nerve and spinal cord, but is now known to affect other regions of the central nervous system and to relapse in some patients.
Diagnosis
The disease is often mediated by antibodies to the aquaporin-4 (AQP-4) water channel, but about 30% of adult patients lack the antibody, and AQP-4 seronegativity is more common in the pediatric population. Another common antibody found in 40%–50% of children with NMOSD targets myelin oligodendrocyte glycoprotein (MOG).
It is important to be aware that false negatives can occur in serology assays, and false positives are common, particularly in ELISA assays, Silvia N. Tenembaum, MD, said during her presentation. For those reasons, serology is not enough for a diagnosis. “Patients should also have compatible symptoms and MRI findings,” said Dr. Tenembaum, director of the pediatric neuroimmunology program at National Pediatric Hospital in Buenos Aires.
According to international consensus criteria, to be diagnosed with NMOSD, AQP-4 seropositive patients should also have at least one core clinical symptom: optic neuritis, acute myelitis, area postrema syndrome, other acute brainstem syndrome, symptomatic narcolepsy or acute diencephalic clinical syndrome, or symptomatic cerebral syndrome. AQP-4 seronegative patients or with unknown status should have at least two core symptoms, one of which must be optic neuritis, acute myelitis, or area postrema syndrome. Both conventional MRI and advanced new techniques are important for achieving differential diagnosis.
The most common symptom in children is optic neuritis, which occurs in 50%-70% of patients. Cerebral syndromes with or without encephalopathy and large tumefactive white matter lesions are also common, according to Dr. Tenembaum.
There are many conditions that mimic the spinal cord and optic nerve symptoms of NMOSD, which must be ruled out. One example is optic myelopathy and vision loss from late-onset biotinylase deficiency. It is critical to rule that out because it is treatable with supplements. Optic neuropathy, papillitis, and papilledema can also resemble NMOSD.
It is critical to achieve an early diagnosis of NMOSD in children, because some MS drugs can worsen NMOSD, according to Thaís Armangue, MD, PhD, head of neuroimmunology at SJD Barcelona Children’s Hospital, who also presented at the session. She pointed out that the MOG antibody, while common in children, is also associated with many demyelinating diseases. Some 50%-60% of children with acute disseminated encephalomyelitis (ADEM) have high titers of MOG antibodies. Although early studies suggested that persistent anti-MOG antibodies were associated with risk of developing MS, more recent studies show it predicts a non-MS disease course, particularly at titers greater than 1:1280, according to Dr. Tenembaum. Persistent anti-MOG antibodies are also associated with relapsing disease, but it is associated with other syndromes besides NMOSD. “The probability is that [MOG antibodies are] useful, but they cannot guide chronic immunotherapy, because even monophasic patients can last maybe 12 months before they become MOG negative, and we cannot wait so many months” to determine treatment course, said Dr. Tenembaum.
For monophasic ADEM or NMOSD, there is no need for chronic treatment. But children with MS and recurrent NMOSD require early chronic immunotherapy because specific therapies have been shown to improve prognosis.
Acute treatment
When it comes to acute treatment of NMOSD, the goal is to suppress the inflammatory attack but also to minimize long-term damage and optimize long-term neurological function. “The potential for irreversible injury with an attack is very high, and cumulative disabilities in NMOSD can result directly from attacks,” E. Ann Yeh, MD, director of the Pediatric MS and Neuroinflammatory Disorders Program at the Hospital for Sick Children at the University of Toronto, said during her talk.
IV steroids are generally the first choice, with a preference for methylprednisolone. Pediatric patients that are MOG antibody positive usually respond better and more quickly than do adults, with rapid daily improvements in mobility, vomiting, and eyesight. Dr. Yeh recommends weaning good responders off steroids because AQP-4 positive patients are likely to relapse without a steroid wean, and antibody testing may be unavailable or results may be delayed. The wean can range from 4 weeks to 4-6 months, depending on antibody status, likelihood of AQP-4 positivity, and clinical parameters.
Inadequate responses are usually pretty evident. If there is only light perception by day 4 or 5, or paralyzed patients are nonambulatory and achieve only twitchy movements by that time, second-line therapies should be considered, including therapeutic plasma exchange (TPE) with 5-7 exchanges or intravenous immunoglobulins (IVIg).
Dr. Yeh called for quick treatment. Whatever you do, “please do it sooner rather than later if you think there’s no response [to steroids],” Dr. Yeh said.
TPE is the first choice, according to Dr. Yeh. “There seems to be a fair amount of information that suggests that if you’re having difficulty getting a response to steroids, TPE can make a difference in these patients,” she said. But in some cases TPE may not be available, and IVIg can be attempted first. If it achieves no or only marginal improvement, TPE can be attempted later, but it must be kept in mind that TPE conducted too soon could wash out IVIg. Patients who get much better on IVIg can undergo a steroid wean, and then be evaluated for prophylactic therapy, said Dr. Yeh.
The evidence for IVIg is limited, reflecting the difficulty of studying treatments in rare populations. Still, when TPE is not available and the patient is quite impaired, IVIg makes sense to try. “Absence of evidence does not mean that the therapy doesn’t work, and I don’t think we should throw out the baby with the bath water,” said Dr. Yeh.
Although IVIg treatment is generally well tolerated, there have been a few serious adverse events, such as anaphylactic shock and aseptic meningitis, according to Andrea Savransky, MD, a pediatrician at National Pediatric Hospital in Buenos Aires, who also spoke at the session. “I think it is important to weigh the benefits against the risk,” Dr. Savransky said. She noted that TPE should not be taken lightly. One study showed more complications in pediatric patients than in adult patients, and it must be performed in specialized centers.
Emerging treaments
Tanuja Chitnis, MD, director of the Partners Pediatric MS Center at Massachusetts General Hospital, Boston, discussed some of the emerging treatments for pediatric NMOSD. Rituximab has been associated with success in some retrospective studies, but dosing should be personalized. Dr. Chitnis reported that B cells can return before 6 months, so she monitors B cells beginning 2 months after induction, redosing after 4 or 5 months rather than 6 if B cells return.
Nevertheless, relapses can still occur after rituximab therapy. “There is room for additional therapies to address this gap,” said Dr. Chitnis. Three new antibodies have received approval for treatment of NMOSD in adults. These include the complement inhibitor eculizumab, the IL-6 receptor antibody satralizumab, and the anti-CD19 antibody inebilizumab. Phase 3 clinical trials in children have been conducted for eculizumab and are in the planning stage for inebilizumab, and pediatric patients were included in pivotal trials for satralizumab.
Eculizumab treatment resulted in a 94.2% reduction in relapse risk in AQP4-positive adults. Satralizumab showed a 79% reduction in relapse risk among AQP-4 positive subjects with NMOSD or neuromyelitis optica and a 34% reduction in those who were AQP-4 negative. The pediatric subgroup had similar levels of response to adults, though the numbers were too small for a subgroup analysis.
In AQP-4 positive patients, inebilizumab treatment yielded a 77% reduction in relapse rate. In all patients, there was a 73% reduction.
For MOG antibody-positive patients with AQP-4 negative disease, novel therapies are at earlier stages of development. Typical MS therapies such as interferon beta and glatiramer acetate don’t seem to be effective. Some that have shown signs of efficacy include azathioprine, mycophenylate mofetil, rituximab, and IVIg infusion, but the state of the field is not encouraging. “This is an observation now being studied in larger cohorts, but in general I have not found that there’s a very strong response to any of these therapies, possibly with the exception of IVIg,” said Dr. Chitnis.
Dr. Tenembaum has no relevant financial disclosures. Dr. Armangue has received speaking honoraria from Novartis and travel expenses for scientific meetings from Merck, Biogen, and Roche. Dr. Yeh is on the scientific advisory board of Juno Therapeutics and has received research support from Biogen. Dr. Chitnis advises Biogen-Idec, Novartis, and Alexion, serves on clinical trial advisory boards for Novartis and Sanofi Aventis, and has received research support from Verily, EMD Serono, and Novartis. Dr. Savransky has received honoraria from Genzyme de Argentina SA.
, but have led to some uncertainty and confusion as well.
At the2020 CNS-ICNA Conjoint Meeting, held virtually this year, presenters discussed some of the challenges of differential diagnosis and treatment choice in pediatric NMOSD, which is easily confused with multiple sclerosis.
NMOSD used to be considered a monophasic disease restricted to the optic nerve and spinal cord, but is now known to affect other regions of the central nervous system and to relapse in some patients.
Diagnosis
The disease is often mediated by antibodies to the aquaporin-4 (AQP-4) water channel, but about 30% of adult patients lack the antibody, and AQP-4 seronegativity is more common in the pediatric population. Another common antibody found in 40%–50% of children with NMOSD targets myelin oligodendrocyte glycoprotein (MOG).
It is important to be aware that false negatives can occur in serology assays, and false positives are common, particularly in ELISA assays, Silvia N. Tenembaum, MD, said during her presentation. For those reasons, serology is not enough for a diagnosis. “Patients should also have compatible symptoms and MRI findings,” said Dr. Tenembaum, director of the pediatric neuroimmunology program at National Pediatric Hospital in Buenos Aires.
According to international consensus criteria, to be diagnosed with NMOSD, AQP-4 seropositive patients should also have at least one core clinical symptom: optic neuritis, acute myelitis, area postrema syndrome, other acute brainstem syndrome, symptomatic narcolepsy or acute diencephalic clinical syndrome, or symptomatic cerebral syndrome. AQP-4 seronegative patients or with unknown status should have at least two core symptoms, one of which must be optic neuritis, acute myelitis, or area postrema syndrome. Both conventional MRI and advanced new techniques are important for achieving differential diagnosis.
The most common symptom in children is optic neuritis, which occurs in 50%-70% of patients. Cerebral syndromes with or without encephalopathy and large tumefactive white matter lesions are also common, according to Dr. Tenembaum.
There are many conditions that mimic the spinal cord and optic nerve symptoms of NMOSD, which must be ruled out. One example is optic myelopathy and vision loss from late-onset biotinylase deficiency. It is critical to rule that out because it is treatable with supplements. Optic neuropathy, papillitis, and papilledema can also resemble NMOSD.
It is critical to achieve an early diagnosis of NMOSD in children, because some MS drugs can worsen NMOSD, according to Thaís Armangue, MD, PhD, head of neuroimmunology at SJD Barcelona Children’s Hospital, who also presented at the session. She pointed out that the MOG antibody, while common in children, is also associated with many demyelinating diseases. Some 50%-60% of children with acute disseminated encephalomyelitis (ADEM) have high titers of MOG antibodies. Although early studies suggested that persistent anti-MOG antibodies were associated with risk of developing MS, more recent studies show it predicts a non-MS disease course, particularly at titers greater than 1:1280, according to Dr. Tenembaum. Persistent anti-MOG antibodies are also associated with relapsing disease, but it is associated with other syndromes besides NMOSD. “The probability is that [MOG antibodies are] useful, but they cannot guide chronic immunotherapy, because even monophasic patients can last maybe 12 months before they become MOG negative, and we cannot wait so many months” to determine treatment course, said Dr. Tenembaum.
For monophasic ADEM or NMOSD, there is no need for chronic treatment. But children with MS and recurrent NMOSD require early chronic immunotherapy because specific therapies have been shown to improve prognosis.
Acute treatment
When it comes to acute treatment of NMOSD, the goal is to suppress the inflammatory attack but also to minimize long-term damage and optimize long-term neurological function. “The potential for irreversible injury with an attack is very high, and cumulative disabilities in NMOSD can result directly from attacks,” E. Ann Yeh, MD, director of the Pediatric MS and Neuroinflammatory Disorders Program at the Hospital for Sick Children at the University of Toronto, said during her talk.
IV steroids are generally the first choice, with a preference for methylprednisolone. Pediatric patients that are MOG antibody positive usually respond better and more quickly than do adults, with rapid daily improvements in mobility, vomiting, and eyesight. Dr. Yeh recommends weaning good responders off steroids because AQP-4 positive patients are likely to relapse without a steroid wean, and antibody testing may be unavailable or results may be delayed. The wean can range from 4 weeks to 4-6 months, depending on antibody status, likelihood of AQP-4 positivity, and clinical parameters.
Inadequate responses are usually pretty evident. If there is only light perception by day 4 or 5, or paralyzed patients are nonambulatory and achieve only twitchy movements by that time, second-line therapies should be considered, including therapeutic plasma exchange (TPE) with 5-7 exchanges or intravenous immunoglobulins (IVIg).
Dr. Yeh called for quick treatment. Whatever you do, “please do it sooner rather than later if you think there’s no response [to steroids],” Dr. Yeh said.
TPE is the first choice, according to Dr. Yeh. “There seems to be a fair amount of information that suggests that if you’re having difficulty getting a response to steroids, TPE can make a difference in these patients,” she said. But in some cases TPE may not be available, and IVIg can be attempted first. If it achieves no or only marginal improvement, TPE can be attempted later, but it must be kept in mind that TPE conducted too soon could wash out IVIg. Patients who get much better on IVIg can undergo a steroid wean, and then be evaluated for prophylactic therapy, said Dr. Yeh.
The evidence for IVIg is limited, reflecting the difficulty of studying treatments in rare populations. Still, when TPE is not available and the patient is quite impaired, IVIg makes sense to try. “Absence of evidence does not mean that the therapy doesn’t work, and I don’t think we should throw out the baby with the bath water,” said Dr. Yeh.
Although IVIg treatment is generally well tolerated, there have been a few serious adverse events, such as anaphylactic shock and aseptic meningitis, according to Andrea Savransky, MD, a pediatrician at National Pediatric Hospital in Buenos Aires, who also spoke at the session. “I think it is important to weigh the benefits against the risk,” Dr. Savransky said. She noted that TPE should not be taken lightly. One study showed more complications in pediatric patients than in adult patients, and it must be performed in specialized centers.
Emerging treaments
Tanuja Chitnis, MD, director of the Partners Pediatric MS Center at Massachusetts General Hospital, Boston, discussed some of the emerging treatments for pediatric NMOSD. Rituximab has been associated with success in some retrospective studies, but dosing should be personalized. Dr. Chitnis reported that B cells can return before 6 months, so she monitors B cells beginning 2 months after induction, redosing after 4 or 5 months rather than 6 if B cells return.
Nevertheless, relapses can still occur after rituximab therapy. “There is room for additional therapies to address this gap,” said Dr. Chitnis. Three new antibodies have received approval for treatment of NMOSD in adults. These include the complement inhibitor eculizumab, the IL-6 receptor antibody satralizumab, and the anti-CD19 antibody inebilizumab. Phase 3 clinical trials in children have been conducted for eculizumab and are in the planning stage for inebilizumab, and pediatric patients were included in pivotal trials for satralizumab.
Eculizumab treatment resulted in a 94.2% reduction in relapse risk in AQP4-positive adults. Satralizumab showed a 79% reduction in relapse risk among AQP-4 positive subjects with NMOSD or neuromyelitis optica and a 34% reduction in those who were AQP-4 negative. The pediatric subgroup had similar levels of response to adults, though the numbers were too small for a subgroup analysis.
In AQP-4 positive patients, inebilizumab treatment yielded a 77% reduction in relapse rate. In all patients, there was a 73% reduction.
For MOG antibody-positive patients with AQP-4 negative disease, novel therapies are at earlier stages of development. Typical MS therapies such as interferon beta and glatiramer acetate don’t seem to be effective. Some that have shown signs of efficacy include azathioprine, mycophenylate mofetil, rituximab, and IVIg infusion, but the state of the field is not encouraging. “This is an observation now being studied in larger cohorts, but in general I have not found that there’s a very strong response to any of these therapies, possibly with the exception of IVIg,” said Dr. Chitnis.
Dr. Tenembaum has no relevant financial disclosures. Dr. Armangue has received speaking honoraria from Novartis and travel expenses for scientific meetings from Merck, Biogen, and Roche. Dr. Yeh is on the scientific advisory board of Juno Therapeutics and has received research support from Biogen. Dr. Chitnis advises Biogen-Idec, Novartis, and Alexion, serves on clinical trial advisory boards for Novartis and Sanofi Aventis, and has received research support from Verily, EMD Serono, and Novartis. Dr. Savransky has received honoraria from Genzyme de Argentina SA.
, but have led to some uncertainty and confusion as well.
At the2020 CNS-ICNA Conjoint Meeting, held virtually this year, presenters discussed some of the challenges of differential diagnosis and treatment choice in pediatric NMOSD, which is easily confused with multiple sclerosis.
NMOSD used to be considered a monophasic disease restricted to the optic nerve and spinal cord, but is now known to affect other regions of the central nervous system and to relapse in some patients.
Diagnosis
The disease is often mediated by antibodies to the aquaporin-4 (AQP-4) water channel, but about 30% of adult patients lack the antibody, and AQP-4 seronegativity is more common in the pediatric population. Another common antibody found in 40%–50% of children with NMOSD targets myelin oligodendrocyte glycoprotein (MOG).
It is important to be aware that false negatives can occur in serology assays, and false positives are common, particularly in ELISA assays, Silvia N. Tenembaum, MD, said during her presentation. For those reasons, serology is not enough for a diagnosis. “Patients should also have compatible symptoms and MRI findings,” said Dr. Tenembaum, director of the pediatric neuroimmunology program at National Pediatric Hospital in Buenos Aires.
According to international consensus criteria, to be diagnosed with NMOSD, AQP-4 seropositive patients should also have at least one core clinical symptom: optic neuritis, acute myelitis, area postrema syndrome, other acute brainstem syndrome, symptomatic narcolepsy or acute diencephalic clinical syndrome, or symptomatic cerebral syndrome. AQP-4 seronegative patients or with unknown status should have at least two core symptoms, one of which must be optic neuritis, acute myelitis, or area postrema syndrome. Both conventional MRI and advanced new techniques are important for achieving differential diagnosis.
The most common symptom in children is optic neuritis, which occurs in 50%-70% of patients. Cerebral syndromes with or without encephalopathy and large tumefactive white matter lesions are also common, according to Dr. Tenembaum.
There are many conditions that mimic the spinal cord and optic nerve symptoms of NMOSD, which must be ruled out. One example is optic myelopathy and vision loss from late-onset biotinylase deficiency. It is critical to rule that out because it is treatable with supplements. Optic neuropathy, papillitis, and papilledema can also resemble NMOSD.
It is critical to achieve an early diagnosis of NMOSD in children, because some MS drugs can worsen NMOSD, according to Thaís Armangue, MD, PhD, head of neuroimmunology at SJD Barcelona Children’s Hospital, who also presented at the session. She pointed out that the MOG antibody, while common in children, is also associated with many demyelinating diseases. Some 50%-60% of children with acute disseminated encephalomyelitis (ADEM) have high titers of MOG antibodies. Although early studies suggested that persistent anti-MOG antibodies were associated with risk of developing MS, more recent studies show it predicts a non-MS disease course, particularly at titers greater than 1:1280, according to Dr. Tenembaum. Persistent anti-MOG antibodies are also associated with relapsing disease, but it is associated with other syndromes besides NMOSD. “The probability is that [MOG antibodies are] useful, but they cannot guide chronic immunotherapy, because even monophasic patients can last maybe 12 months before they become MOG negative, and we cannot wait so many months” to determine treatment course, said Dr. Tenembaum.
For monophasic ADEM or NMOSD, there is no need for chronic treatment. But children with MS and recurrent NMOSD require early chronic immunotherapy because specific therapies have been shown to improve prognosis.
Acute treatment
When it comes to acute treatment of NMOSD, the goal is to suppress the inflammatory attack but also to minimize long-term damage and optimize long-term neurological function. “The potential for irreversible injury with an attack is very high, and cumulative disabilities in NMOSD can result directly from attacks,” E. Ann Yeh, MD, director of the Pediatric MS and Neuroinflammatory Disorders Program at the Hospital for Sick Children at the University of Toronto, said during her talk.
IV steroids are generally the first choice, with a preference for methylprednisolone. Pediatric patients that are MOG antibody positive usually respond better and more quickly than do adults, with rapid daily improvements in mobility, vomiting, and eyesight. Dr. Yeh recommends weaning good responders off steroids because AQP-4 positive patients are likely to relapse without a steroid wean, and antibody testing may be unavailable or results may be delayed. The wean can range from 4 weeks to 4-6 months, depending on antibody status, likelihood of AQP-4 positivity, and clinical parameters.
Inadequate responses are usually pretty evident. If there is only light perception by day 4 or 5, or paralyzed patients are nonambulatory and achieve only twitchy movements by that time, second-line therapies should be considered, including therapeutic plasma exchange (TPE) with 5-7 exchanges or intravenous immunoglobulins (IVIg).
Dr. Yeh called for quick treatment. Whatever you do, “please do it sooner rather than later if you think there’s no response [to steroids],” Dr. Yeh said.
TPE is the first choice, according to Dr. Yeh. “There seems to be a fair amount of information that suggests that if you’re having difficulty getting a response to steroids, TPE can make a difference in these patients,” she said. But in some cases TPE may not be available, and IVIg can be attempted first. If it achieves no or only marginal improvement, TPE can be attempted later, but it must be kept in mind that TPE conducted too soon could wash out IVIg. Patients who get much better on IVIg can undergo a steroid wean, and then be evaluated for prophylactic therapy, said Dr. Yeh.
The evidence for IVIg is limited, reflecting the difficulty of studying treatments in rare populations. Still, when TPE is not available and the patient is quite impaired, IVIg makes sense to try. “Absence of evidence does not mean that the therapy doesn’t work, and I don’t think we should throw out the baby with the bath water,” said Dr. Yeh.
Although IVIg treatment is generally well tolerated, there have been a few serious adverse events, such as anaphylactic shock and aseptic meningitis, according to Andrea Savransky, MD, a pediatrician at National Pediatric Hospital in Buenos Aires, who also spoke at the session. “I think it is important to weigh the benefits against the risk,” Dr. Savransky said. She noted that TPE should not be taken lightly. One study showed more complications in pediatric patients than in adult patients, and it must be performed in specialized centers.
Emerging treaments
Tanuja Chitnis, MD, director of the Partners Pediatric MS Center at Massachusetts General Hospital, Boston, discussed some of the emerging treatments for pediatric NMOSD. Rituximab has been associated with success in some retrospective studies, but dosing should be personalized. Dr. Chitnis reported that B cells can return before 6 months, so she monitors B cells beginning 2 months after induction, redosing after 4 or 5 months rather than 6 if B cells return.
Nevertheless, relapses can still occur after rituximab therapy. “There is room for additional therapies to address this gap,” said Dr. Chitnis. Three new antibodies have received approval for treatment of NMOSD in adults. These include the complement inhibitor eculizumab, the IL-6 receptor antibody satralizumab, and the anti-CD19 antibody inebilizumab. Phase 3 clinical trials in children have been conducted for eculizumab and are in the planning stage for inebilizumab, and pediatric patients were included in pivotal trials for satralizumab.
Eculizumab treatment resulted in a 94.2% reduction in relapse risk in AQP4-positive adults. Satralizumab showed a 79% reduction in relapse risk among AQP-4 positive subjects with NMOSD or neuromyelitis optica and a 34% reduction in those who were AQP-4 negative. The pediatric subgroup had similar levels of response to adults, though the numbers were too small for a subgroup analysis.
In AQP-4 positive patients, inebilizumab treatment yielded a 77% reduction in relapse rate. In all patients, there was a 73% reduction.
For MOG antibody-positive patients with AQP-4 negative disease, novel therapies are at earlier stages of development. Typical MS therapies such as interferon beta and glatiramer acetate don’t seem to be effective. Some that have shown signs of efficacy include azathioprine, mycophenylate mofetil, rituximab, and IVIg infusion, but the state of the field is not encouraging. “This is an observation now being studied in larger cohorts, but in general I have not found that there’s a very strong response to any of these therapies, possibly with the exception of IVIg,” said Dr. Chitnis.
Dr. Tenembaum has no relevant financial disclosures. Dr. Armangue has received speaking honoraria from Novartis and travel expenses for scientific meetings from Merck, Biogen, and Roche. Dr. Yeh is on the scientific advisory board of Juno Therapeutics and has received research support from Biogen. Dr. Chitnis advises Biogen-Idec, Novartis, and Alexion, serves on clinical trial advisory boards for Novartis and Sanofi Aventis, and has received research support from Verily, EMD Serono, and Novartis. Dr. Savransky has received honoraria from Genzyme de Argentina SA.
FROM CNS-ICNA 2020
Worldwide measles vaccination is flagging
After almost 2 decades of progress, the global state of measles vaccination and measles mortality is deteriorating.
One of the most serious concerns of measles infection is its long-term neurological complications, including the fatal subacute sclerosing panencephalitis (SSPE) and measles inclusion-body encephalitis (MIBE), which is usually seen in immune deficient children. Although some efforts are being made to determine which patients might be most vulnerable to these outcomes, and to treat them, the best approach is still prevention and vaccination, according to Banu Anlar, MD, of Hacettepe University, Ankara, Turkey, who spoke during a session at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year.
Worldwide vaccination strategies have slipped in recent years, leading to upticks in measles cases and vaccination rates. As a result, in 2018 the World Health Organization postponed its goal of eliminating measles by 2020. Future eradication goals will likely need to be modified, according to Anaita Udwadia Hegde MD, a pediatric neurologist in Mumbai, India, who also presented at the session.
After measles deaths dropped 74% between 2000 and 2010, coinciding with widespread increases in vaccination, the WHO felt emboldened to deal the disease a knockout blow. In 2010, it held a Global Technical Consultation to determine the feasibility of an eradication campaign, which concluded it should be possible by 2020. Several characteristics of measles made that a reasonable goal: It is passed only among humans, with no known animal reservoir; natural infection grants lifelong immunity; there is only one serotype; the virus is genetically stable; the vaccine is safe and leads to 95%-97% seroconversion after two doses, which provides long-term protection against known genotypes; the disease is easily recognized and tested for; and it had been successfully eliminated already in some regions of the world.
As of 2017, analyses showed that the vaccination program saved the lives of about 1.5 million children. That was a cause for celebration, but the goal of eradication has remained elusive. Vaccination rates have trailed targets. In 2018, UNICEF and WHO estimated that 86% of children globally received the first measles vaccine, unchanged from 2010 and below the goal of 95%. Only 69% of children received the second dose, below the goal of 80%. Four countries in Europe lost their measles elimination status in 2018.
Other attempts to eradicate diseases have met with mixed results. The only full success was smallpox, eliminated in 1977. Similar efforts with polio, malaria, guinea worm, and now measles have all come up short. Those failures could complicate future efforts because global agencies and donors may be leery of past failures because of potential harm to their reputations, according to Dr. Hegde.
Such programs require sustained financial commitment and political support as well as local trust. Nevertheless, they must continue for ethical reasons, said Dr. Hegde, but also for economic ones: Every $1 spent on vaccination programs saves $58 in future costs in low- and middle-income countries. Missed childhood vaccination also results in future vulnerable teenagers and young adults, and these populations are much harder to reach and can drive large outbreaks.
Several factors are contributing to the global regression in vaccine coverage, according to Kristen Feemster, MD, MPH, a pediatric infectious disease physician and the global director of medical affairs at Merck. Globalization has enabled the spread of the disease. Most cases in the United States are imported by travelers to countries where the disease is endemic. “Measles can happen anywhere in the world, and when it does it can travel and spread. If you have an unvaccinated traveler who is exposed to measles abroad, they can return home and spread it to anyone else who is unvaccinated or not otherwise immune. When we see cases they’ve been sporadic, but if you return to a community where immunization rates are low, you have the potential for more sustained spread,” Dr. Feemster said during her presentation.
Why are so many travelers unvaccinated? A key reason is that vaccine hesitance is growing. Most affected individuals involved in outbreaks are unvaccinated, usually by choice rather than for medical reasons. Concerns continue over the measles vaccine and autism, growing out of the debunked studies of Andrew Wakefield. In one example, a Somali community in Minnesota experienced a higher than usual number of autism cases and parents sought reasons to explain it. They discovered the supposed connection between vaccination and autism, and Wakefield himself met with a group of them. The result was a drop in vaccination and, in 2011 and 2017, sizable measles outbreaks.
2020 has of course brought a fresh challenge to measles vaccine with the COVID-19 pandemic, which has reduced access to health care and shifted scientific and health care interest away from measles and other vaccine-preventable diseases. On the positive side, social distancing, mask wearing, and restricted movement are likely reducing exposure to measles, but reduced vaccination rates are likely to result in future outbreaks. “There’s been a significant decrease in rates for routine immunizations globally, so there’s a potential for yet another resurgence of measles and other vaccine-preventable diseases,” said Dr. Feemster.
Dr. Feemster is an employee of Merck. Dr. Anlar and Dr. Hegde did not disclose any relevant financial relationships.
After almost 2 decades of progress, the global state of measles vaccination and measles mortality is deteriorating.
One of the most serious concerns of measles infection is its long-term neurological complications, including the fatal subacute sclerosing panencephalitis (SSPE) and measles inclusion-body encephalitis (MIBE), which is usually seen in immune deficient children. Although some efforts are being made to determine which patients might be most vulnerable to these outcomes, and to treat them, the best approach is still prevention and vaccination, according to Banu Anlar, MD, of Hacettepe University, Ankara, Turkey, who spoke during a session at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year.
Worldwide vaccination strategies have slipped in recent years, leading to upticks in measles cases and vaccination rates. As a result, in 2018 the World Health Organization postponed its goal of eliminating measles by 2020. Future eradication goals will likely need to be modified, according to Anaita Udwadia Hegde MD, a pediatric neurologist in Mumbai, India, who also presented at the session.
After measles deaths dropped 74% between 2000 and 2010, coinciding with widespread increases in vaccination, the WHO felt emboldened to deal the disease a knockout blow. In 2010, it held a Global Technical Consultation to determine the feasibility of an eradication campaign, which concluded it should be possible by 2020. Several characteristics of measles made that a reasonable goal: It is passed only among humans, with no known animal reservoir; natural infection grants lifelong immunity; there is only one serotype; the virus is genetically stable; the vaccine is safe and leads to 95%-97% seroconversion after two doses, which provides long-term protection against known genotypes; the disease is easily recognized and tested for; and it had been successfully eliminated already in some regions of the world.
As of 2017, analyses showed that the vaccination program saved the lives of about 1.5 million children. That was a cause for celebration, but the goal of eradication has remained elusive. Vaccination rates have trailed targets. In 2018, UNICEF and WHO estimated that 86% of children globally received the first measles vaccine, unchanged from 2010 and below the goal of 95%. Only 69% of children received the second dose, below the goal of 80%. Four countries in Europe lost their measles elimination status in 2018.
Other attempts to eradicate diseases have met with mixed results. The only full success was smallpox, eliminated in 1977. Similar efforts with polio, malaria, guinea worm, and now measles have all come up short. Those failures could complicate future efforts because global agencies and donors may be leery of past failures because of potential harm to their reputations, according to Dr. Hegde.
Such programs require sustained financial commitment and political support as well as local trust. Nevertheless, they must continue for ethical reasons, said Dr. Hegde, but also for economic ones: Every $1 spent on vaccination programs saves $58 in future costs in low- and middle-income countries. Missed childhood vaccination also results in future vulnerable teenagers and young adults, and these populations are much harder to reach and can drive large outbreaks.
Several factors are contributing to the global regression in vaccine coverage, according to Kristen Feemster, MD, MPH, a pediatric infectious disease physician and the global director of medical affairs at Merck. Globalization has enabled the spread of the disease. Most cases in the United States are imported by travelers to countries where the disease is endemic. “Measles can happen anywhere in the world, and when it does it can travel and spread. If you have an unvaccinated traveler who is exposed to measles abroad, they can return home and spread it to anyone else who is unvaccinated or not otherwise immune. When we see cases they’ve been sporadic, but if you return to a community where immunization rates are low, you have the potential for more sustained spread,” Dr. Feemster said during her presentation.
Why are so many travelers unvaccinated? A key reason is that vaccine hesitance is growing. Most affected individuals involved in outbreaks are unvaccinated, usually by choice rather than for medical reasons. Concerns continue over the measles vaccine and autism, growing out of the debunked studies of Andrew Wakefield. In one example, a Somali community in Minnesota experienced a higher than usual number of autism cases and parents sought reasons to explain it. They discovered the supposed connection between vaccination and autism, and Wakefield himself met with a group of them. The result was a drop in vaccination and, in 2011 and 2017, sizable measles outbreaks.
2020 has of course brought a fresh challenge to measles vaccine with the COVID-19 pandemic, which has reduced access to health care and shifted scientific and health care interest away from measles and other vaccine-preventable diseases. On the positive side, social distancing, mask wearing, and restricted movement are likely reducing exposure to measles, but reduced vaccination rates are likely to result in future outbreaks. “There’s been a significant decrease in rates for routine immunizations globally, so there’s a potential for yet another resurgence of measles and other vaccine-preventable diseases,” said Dr. Feemster.
Dr. Feemster is an employee of Merck. Dr. Anlar and Dr. Hegde did not disclose any relevant financial relationships.
After almost 2 decades of progress, the global state of measles vaccination and measles mortality is deteriorating.
One of the most serious concerns of measles infection is its long-term neurological complications, including the fatal subacute sclerosing panencephalitis (SSPE) and measles inclusion-body encephalitis (MIBE), which is usually seen in immune deficient children. Although some efforts are being made to determine which patients might be most vulnerable to these outcomes, and to treat them, the best approach is still prevention and vaccination, according to Banu Anlar, MD, of Hacettepe University, Ankara, Turkey, who spoke during a session at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year.
Worldwide vaccination strategies have slipped in recent years, leading to upticks in measles cases and vaccination rates. As a result, in 2018 the World Health Organization postponed its goal of eliminating measles by 2020. Future eradication goals will likely need to be modified, according to Anaita Udwadia Hegde MD, a pediatric neurologist in Mumbai, India, who also presented at the session.
After measles deaths dropped 74% between 2000 and 2010, coinciding with widespread increases in vaccination, the WHO felt emboldened to deal the disease a knockout blow. In 2010, it held a Global Technical Consultation to determine the feasibility of an eradication campaign, which concluded it should be possible by 2020. Several characteristics of measles made that a reasonable goal: It is passed only among humans, with no known animal reservoir; natural infection grants lifelong immunity; there is only one serotype; the virus is genetically stable; the vaccine is safe and leads to 95%-97% seroconversion after two doses, which provides long-term protection against known genotypes; the disease is easily recognized and tested for; and it had been successfully eliminated already in some regions of the world.
As of 2017, analyses showed that the vaccination program saved the lives of about 1.5 million children. That was a cause for celebration, but the goal of eradication has remained elusive. Vaccination rates have trailed targets. In 2018, UNICEF and WHO estimated that 86% of children globally received the first measles vaccine, unchanged from 2010 and below the goal of 95%. Only 69% of children received the second dose, below the goal of 80%. Four countries in Europe lost their measles elimination status in 2018.
Other attempts to eradicate diseases have met with mixed results. The only full success was smallpox, eliminated in 1977. Similar efforts with polio, malaria, guinea worm, and now measles have all come up short. Those failures could complicate future efforts because global agencies and donors may be leery of past failures because of potential harm to their reputations, according to Dr. Hegde.
Such programs require sustained financial commitment and political support as well as local trust. Nevertheless, they must continue for ethical reasons, said Dr. Hegde, but also for economic ones: Every $1 spent on vaccination programs saves $58 in future costs in low- and middle-income countries. Missed childhood vaccination also results in future vulnerable teenagers and young adults, and these populations are much harder to reach and can drive large outbreaks.
Several factors are contributing to the global regression in vaccine coverage, according to Kristen Feemster, MD, MPH, a pediatric infectious disease physician and the global director of medical affairs at Merck. Globalization has enabled the spread of the disease. Most cases in the United States are imported by travelers to countries where the disease is endemic. “Measles can happen anywhere in the world, and when it does it can travel and spread. If you have an unvaccinated traveler who is exposed to measles abroad, they can return home and spread it to anyone else who is unvaccinated or not otherwise immune. When we see cases they’ve been sporadic, but if you return to a community where immunization rates are low, you have the potential for more sustained spread,” Dr. Feemster said during her presentation.
Why are so many travelers unvaccinated? A key reason is that vaccine hesitance is growing. Most affected individuals involved in outbreaks are unvaccinated, usually by choice rather than for medical reasons. Concerns continue over the measles vaccine and autism, growing out of the debunked studies of Andrew Wakefield. In one example, a Somali community in Minnesota experienced a higher than usual number of autism cases and parents sought reasons to explain it. They discovered the supposed connection between vaccination and autism, and Wakefield himself met with a group of them. The result was a drop in vaccination and, in 2011 and 2017, sizable measles outbreaks.
2020 has of course brought a fresh challenge to measles vaccine with the COVID-19 pandemic, which has reduced access to health care and shifted scientific and health care interest away from measles and other vaccine-preventable diseases. On the positive side, social distancing, mask wearing, and restricted movement are likely reducing exposure to measles, but reduced vaccination rates are likely to result in future outbreaks. “There’s been a significant decrease in rates for routine immunizations globally, so there’s a potential for yet another resurgence of measles and other vaccine-preventable diseases,” said Dr. Feemster.
Dr. Feemster is an employee of Merck. Dr. Anlar and Dr. Hegde did not disclose any relevant financial relationships.
FROM CNS-ICNA 2020