YOSEMITE, CALIF. — “As you follow the research in pediatric emergency medicine, it really parallels the practice model of the community,” Dr. Richard M. Cantor said during a pediatric conference sponsored by Symposia Medicus.
On topics from bacteremia, to migraines, to mononucleosis, he summarized recent studies in the literature that have affected the practice of pediatric emergency medicine.
“Any of you who have been in practice for more than 5 or 7 years can see the trends and where these issues have come from,” said Dr. Cantor, director of pediatric emergency services at University Hospital in Syracuse, N.Y.
Young Febrile Infants
Dr. Bema K. Bonsu of Children's Hospital, Columbus, Ohio, and Dr. Marvin B. Harper of Children's Hospital, Boston, set out to estimate the accuracy of the total peripheral white blood count as a screening tool for bacteremia in febrile young infants. They evaluated logistic models for predicting bacteremia that are based on the total peripheral white blood cell count by following 3,810 infants aged 0–89 days who had a temperature in triage of greater than or equal to 100.4° F. (Ann. Emerg. Med. 2003;42:216–25).
The rate of bacteremia was 1% (38/3,810), but the sensitivity and specificity of the white blood count test was 79% and 5%, respectively, at a cutoff of greater than or equal to 5,000 cells/mm
“Thus, decisions to obtain blood cultures should not rely on this test,” said Dr. Cantor, who also is associate professor of emergency medicine and pediatrics at State University of New York (Syracuse) Upstate Medical University.
Risk for Serious Bacterial Infections
Dr. M. Olivia Titus and Dr. Seth W. Wright of Vanderbilt University Medical Center, Nashville, Tenn., investigated the prevalence of serious bacterial infections (SBI) in 174 febrile infants who were younger than 8 weeks of age and had documented respiratory syncytial virus (RSV) and compared them with 174 gender- and age-matched control subjects who were febrile and RSV-negative.
Overall, only 2 patients in the RSV group had SBI (both urinary tract infections), compared with 22 in the control group (17 were UTIs). They concluded that the risk of SBI in febrile infants with RSV infection is very low (Pediatrics 2003;112:282–4).
“Full septic work-ups may not be necessary, and it is prudent to look at the urine [for evidence of UTI],” Dr. Cantor said. “This is important.”
Bacteremia, Antibiotic Use in RSV
A separate study was conducted by Dr. P. Bloomfield and associates at the Children's Hospital at Westmead, New South Wales, Australia, to examine the frequency of and risk factors for bacteremia in 1,795 children aged 0–14 years hospitalized with RSV infection over a 4-year period (Arch. Dis. Child. 2004;89:363–7).
Only 11 (0.6%) of the 1,795 RSV-positive children had bacteremia. RSV-positive children were more likely to be bacteremic if they had nosocomial RSV (6.5%), cyanotic congenital heart disease (6.6%), or were admitted to the pediatric ICU (2.9%). “They concluded that bacteremia is rare and that certain characteristics help you identify bacteremic children,” Dr. Cantor said.
Rapid Diagnosis of Influenza
Dr. Aleta B. Bonner and her colleagues at the University of Alabama, Birmingham, attempted to determine the impact of the rapid diagnosis of influenza in the pediatric emergency department on physician decision making and patient management.
The investigators screened 391 patients aged 2 months to 21 years for fever and cough, coryza, myalgias, headache, and/or malaise and randomized them to one of two groups; 202 were influenza positive and ended up randomized roughly equally in the two groups.
In group 1, the attending physician was aware of the rapid influenza test results. Nasopharyngeal swabs were obtained and immediately tested with the flu optical immunoassay (FluOIA) test for influenza A and B, and the results were placed on the chart before the patient was evaluated by the attending physician.
In group 2, the attending physician was unaware of the test results. Nasopharyngeal swabs were obtained, stored, and tested within 24 hours.
Physician awareness of a rapid diagnosis of influenza significantly reduced the number of laboratory tests and radiographs ordered, as well as the associated charges; decreased antibiotic use; increased antiviral use; and reduced the length of time to discharge (Pediatrics 2003;112:363–7).
“This is a big deal,” Dr. Cantor remarked. “You go into the exam room and you say, 'Good news. Your baby has the flu.' They ask, 'Is my child gonna die?' I've had that question. What do you tell them? [I say] 'I have this bank of testing in front of me that gives me viral answers.'”