SUDDEN-INFANT-DEATH-SYNDROME - A SEARCH FOR ALLERGEN HYPERSENSITIVITY

Background: Sudden infant death syndrome (SIDS) remains a diagnosis by exclusion which leaves few if any pathologic clues to its etiology. P revious evaluations for anaphylaxis in SIDS have been few and limited. Objective: To analyze forensic blood specimens for evidence of anaphy laxis in 51 (43 boys and 8 girls) children dying of SIDS and 13 (9 boy s and 4 girls) age-matched controls who died from defined, nonanaphyla ctic causes. Methods: Specimens collected over a 5-year period were as sayed for (1) total IgE (IU/mL) by immunoenzymatic assay; (2) latex, c at, dust mite (Dermatophagoides farinae and Dermatophagoides pteronyss inus), milk, soy, wheat, peanuts, egg, and tomato specific-IgE by PAST ; and (3) serum tryptase levels (U/L) by radioimmunoassay. Results: Th e 51 SIDS cases (median age 3 months; range 1 to 9 months) and 13 cont rol cases (median age 4 months; range 1 to 11 months) demonstrated sim ilar total IgE of 9.8 +/- 1.1 IU/mL (mean +/- SEM) and 10.9 +/- 2.8 IU /mL (P =.59). The frequency of detectable (>0.5 U/L) serum tryptase le vels among SIDS cases (10/51) was similar to controls (3/13, P =.72). The frequency of positive PAST tests was 39% (20/51) in SIDS and 38% ( 5/13) in control subjects (P =.99). Differences in frequencies of posi tive PAST tests in SIDS and control cases were not statistically signi ficant for any allergen tested. The most frequently detected allergen- specific IgE, to milk, was similar in SIDS (22%) and controls (31%, P =.48). Conclusions: Elevated tryptase levels and allergen-specific IgE (milk, soy, wheat, peanuts, egg, tomato, dust mites, cat, and latex) were demonstrated in some infant SIDS deaths but were no more common t han in controls. We conclude that anaphylaxis is probably an uncommon etiology for SIDS.