John, age 16, is admitted to our inpatient psychiatric unit, complaining of “a 2-week constant headache” caused by “voices arguing in my head.” He has lived in Mexico with an uncle for 6 months but returned home last week for medical evaluation of his headaches.
His parents report that John developed normally until 3 years ago, when he gradually lost interest in his favorite activities and became socially withdrawn. He has not attended school in 2 years. He has no history of illicit drug use and is not taking prescription or over the-counter medications.
Complete physical examination, neurologic exam, and routine screening lab test results are normal. Thinking that a high lead content of cookware used in Mexico might be causing John’s symptoms, we order a lead level: result-0.2 mg/dL (
We diagnose schizophreniform disorder, but John’s parents refuse to accept this diagnosis. They repeatedly ask if we can do more to identify a medical cause of their son’s psychiatric symptoms.
As in John’s case, young patients or their parents may resist the diagnosis of a chronic mental illness such as schizophrenia. Understandably, they may be invested in trying to identify “medically treatable” causes. You can address their anxieties by showing them that you have systematically evaluated medical causes of psychosis.
We offer such a tool: an algorithm and tables to help you identify common and rare medical conditions that may cause or exacerbate psychotic symptoms in patients ages 3 to 18.
An evidence-based algorithm
Multiple factors—developmental, psychological, family, environmental, or medical—typically cause psychotic symptoms in a child or adolescent. Evaluating all possibilities is essential, but guidelines tend to minimize medical causes. American Academy of Child and Adolescent Psychiatry guidelines, for example, recommend that “all medical disorders (including general medical conditions and substance-induced disorders) are ruled out,”1 but they do not specify which medical conditions to consider.
To supplement existing guidelines, we searched the literature and developed an evidence-based algorithm to help you systematically consider medical causes of pediatric psychotic symptoms. We excluded children age 2
How to use it. The algorithm walks you through a medical systems review. You begin with a complete history, then address six causes of psychotic symptoms: substance abuse, medication reactions, general medical conditions, unexplained somatic symptoms (such as from toxic environmental exposures), developmental and learning disabilities, and atypical presentations.
Don’t stop if you find one possible cause of psychotic symptoms; continue to the end of the algorithm. The more factors you identify, the greater your chance of finding a treatable cause that may ameliorate your patient’s symptoms.
To make the algorithm clinically useful, we listed conditions in order of decreasing probability of causing psychotic symptoms. For example, the first cause listed is substance-induced disorders,3 which are most common among adolescent patients. We also “triaged” medical conditions from common to rare (based on estimated prevalence of association with psychotic symptoms), listing rare causes only in cases of atypical presentation or treatment resistance.
Supporting tables. The following discussion summarizes data that support the algorithm and its tables:
- medications reported to cause psychosis (Table 1)
- medical conditions most likely to cause psychosis (Table 2)
- medical conditions that rarely cause psychosis (Table 3).
Drugs that may cause psychotic symptoms
| Drug class | Psychotic symptoms | |
|---|---|---|
| Bizarre behavior/delusions | Auditory or visual hallucinations | |
| Amphetamine-like drugs | X | X |
| Anabolic steroids | X | |
| Angiotensin-converting enzyme (ACE) inhibitors | X | |
| Anticholinergics and atropine | X | X |
| Antidepressants, tricyclic | X | |
| Antiepileptics | X | |
| Barbiturates | X | X |
| Benzodiazepines | X | X |
| Beta-adrenergic blockers | X | X |
| Calcium channel blockers | X | |
| Cephalosporins | X | X |
| Corticosteroids | X | |
| Dopamine receptor agonists | X | X |
| Fluoroquinolone antibiotics | X | X |
| Histamine H1 receptor blockers | X | |
| Histamine H2 receptor blockers | X | |
| HMG-CoA reductase inhibitors | X | |
| Nonsteroidal anti-inflammatory drugs | X | |
| Opioids | X | X |
| Procaine derivatives (procainamide, procaine penicillin G) | X | X |
| Salicylates | X | X |
| Selective serotonin reuptake inhibitors | X | |
| Sulfonamides | X | |
| Source: Adapted from reference 10. | ||
Common medical conditions that may cause pediatric psychosis symptoms*
| Category | Conditions not to forget | Common symptoms/comments |
|---|---|---|
| Rheumatologic | Lupus erythematosus | Joint pain, fever, facial butterfly rash, prolonged fatigue |
| Infectious | Viral encephalitis | Fever, headache, mental status change; may occur in perinatal period |
| Neurologic | Multiple sclerosis | Varied neurologic deficits, especially ophthalmologic changes and weakness |
| Neurosyphilis | Personality change, ataxia, stroke, ophthalmic symptoms | |
| Seizure (temporal lobe epilepsy, interictal psychosis) | Paroxysmal periods of sudden change in mood, behavior, or motor activity with or without loss of consciousness | |
| Toxicologic | Carbon monoxide poisoning | Shortness of breath, mild nausea, headache, dizziness |
| * Clinically significant symptoms that meet DSM-IV-TR criteria for a primary psychiatric disorder. | ||
| Click here to view citations supporting statements in this table | ||
Medical conditions that rarely cause pediatric psychosis symptoms*
| Category/condition | Symptoms/comments |
|---|---|
| Endocrine | |
| Hyperthyroidism | Tachycardia, weight loss, excessive sweating, tiredness, inability to sleep, diarrhea, shakiness, muscle weakness |
| Thymoma/myasthenia gravis | Shortness of breath, swelling of face, muscle weakness (especially around eyes) |
| Hematologic | |
| Porphyria (acute intermittent porphyria, porphyria variegate) | Intermittent abdominal pain (severe) accompanied by dark urine |
| Genetic | |
| Fabry’s disease | Burning sensations in hands and feet that worsen with exercise and hot weather |
| Niemann-Pick disease, type C | Vertical gaze palsy, hepatosplenomegaly, jaundice, ataxia |
| Prader-Willi syndrome | Obesity, hyperphagia, mild to moderate mental retardation, hypogonadism, tantrums, obsessive-compulsive disorder |
| Infectious | |
| Epstein-Barr virus | Fever, sore throat, adenopathy, fatigue, poor concentration |
| Lyme disease | Target lesion, fever; high-risk geographic area |
| Malaria/typhoid fever | Fever, mental status change; endemic area |
| Mycoplasma pneumonia | Fever, mental status change; may occur in absence of pneumonia |
| Rabies | History of exposure |
| Metabolic | |
| Citrullinemia | Mental status change, high plasma citrulline and ammonia |
| Tay-Sachs disease | Unsteadiness of gait and progressive neurologic deterioration |
| Homocystinuria | Dislocated lenses, blood clots, tall stature, some mental retardation |
| Juvenile metachromatic leukodystrophy | Cognitive decline, ataxia, pyramidal signs, peripheral neuropathy, dystonia; 60% of cases present before age 3 |
| Neurologic | |
| Central pontine myelinolysis | Suspect in patient with pathogenic polydipsia |
| Huntington’s disease | Chorea, myoclonic seizures, poor coordination, emotional lability |
| Moyamoya disease | Paresis, syncopal episodes |
| Narcolepsy | Excessive daytime sleepiness, cataplexy |
| Subacute sclerosing panencephalitis | Visual hallucinations, loss of developmental milestones |
| Traumatic brain injury | Occurring 4 to 5 years after a loss of consciousness >30 minutes |
| Wilson’s disease | Tremors, muscle spasticity, possible liver inflammation |
| Nutritional | |
| Pellagra (vitamin B6 deficiency) | Redness, swelling of mouth and tongue, diarrhea, rash, abnormal mental functioning; seen with isoniazid treatment for tuberculosis |
| Oncologic | |
| Cancers (pancreatic, CNS papilloma, germinoma) | Postural headache, neurologic signs, increased intracranial pressure, early morning nausea, vomiting |
| Toxicologic | |
| Lead intoxication | Headache, fatigue, mental status change |
| Mercury poisoning | Abdominal pain, bleeding gums, metallic taste; history of exposure |
| * Clinically significant symptoms that meet DSM-IV-TR criteria for a primary psychiatric disorder. | |
| Click here to view citations supporting statements in this table | |