PURPOSE OF STUDY.
To investigate clinical characteristics of children evaluated for primary immunodeficiency (PID) and address the utility of the “10 Warning Signs of Primary Immunodeficiency” developed in 1994 by expert consensus and published by the Jeffry Modell Foundation (http://www.jfmworld.com).
The study included 141 children (birth to 21 years) evaluated in the Allergy/Immunology clinic at Children’s Hospital of Pittsburgh for possible PID in 2004–2005. Patients were identified by International Classification of Diseases, Ninth Revision, codes indicative of immunodeficiency or recurrent infection.
This was a retrospective chart review. Patients were classified with PID if they met published diagnostic criteria and were diagnosed with immunodeficiency. Those with PID were evaluated for the presence of warning signs and categorized as those who met 1 or more of the warning signs (WS+) and those who did not (WS−).
Twenty-three percent of patients were diagnosed with PID. Of those with PID, <70% met 1 or more criteria set forth in the warning signs. The most common warning signs met were recurrent otitis media, recurrent sinusitis, and need for intravenous antibiotics. Sensitivity of the warning signs was 63% and specificity was 23%.
“10 Warning Signs of Primary Immunodeficiency” were found to have low specificity and relatively low sensitivity. Study numbers were too small to draw conclusions regarding the utility of specific warning signs.
The primary pediatrician’s question of when to refer a patient for workup of PID is a challenging one. The study suggests that this widely used screening tool has relatively low sensitivity and, therefore, the potential to miss PID cases. When clinical suspicion is high, immune evaluation should be considered even if a patient does not meet >1 of these 10 warning signs. Further studies are needed to develop a more optimal screening tool and to evaluate which specific signs are most relevant.
- Copyright © 2012 by the American Academy of Pediatrics