A cluster of anaphylactic reactions in children with spina bifida during general anesthesia: epidemiologic features, risk factors, and latex hypersensitivity.

BACKGROUND: Anaphylactic reactions (ARs) in high-risk pediatric patients undergoing general anesthesia, especially those with spina bifida, have been attributed to anesthetics, muscle relaxants, antimicrobials, ethylene oxide, and latex.
METHODS: To identify risk factors for AR during general anesthesia and to investigate the role of latex allergy, we studied epidemiologic and immunologic characteristics of patients with ARs during general anesthesia during a 13-month cluster of such reactions at Children's Hospital of Wisconsin (case patients). Patients with AR were compared with patients with spina bifida undergoing uneventful general anesthesia during the same period (control patients). For each case patient and control patient, we conducted a chart review; a parental interview; skin prick testing with latex, anesthetics, aeroallergens, and banana extract; ELISA and RAST for latex-specific IgE; a total serum IgE; and an ELISA for IgE antibody to ethylene oxide.
RESULTS: Anaphylactic reactions occurred exclusively in patients with spina bifida (n = 10) or patients with a congenital urinary tract anomaly (n = 1). Case-patients were more likely than control patients to have a history of asthma (p = 0.002), rubber contact allergy (p = 0.001), food allergy (p = 0.001), rash caused by adhesive tape (p = 0.05), daily rectal disimpaction (p < 0.001), nine or more prior surgical procedures (p < 0.002), latex-specific IgE (p = 0.027), or elevated total serum IgE levels (p = 0.002). Multivariate analysis identified non-white race, rubber contact allergy, history of food allergy, and nine or more surgical procedures as significant independent risk factors. Logistic model equation identified the predicted probability of AR with a sensitivity, specificity, and positive predictive value of 82%, 97%, and 82%, respectively.
CONCLUSIONS: These findings demonstrate that atopy, especially symptomatic latex allergy, is associated with AR during anesthesia in patients with spina bifida. Until a standardized latex test is available, a medical history of immediate rubber contact allergy, non-white race, food allergy, or nine or more prior surgical procedures can identify patients with spina bifida at highest risk for ARs. A complete history, including rubber contact and food allergy, should be compiled on all patients with spina bifida before surgery.