Source of Support: None, Conflict of Interest: None
130 Patients attending allergy clinic were screened for skin test response to specific allergens using histamine phosphate as a positive control. Immediate reaction after 20 to 30 minutes and late phase reaction (LPCR) after six to eight hours of allergen Injection were noted. Profile and significance of the late phase cutaneous reaction were determined in asthmatics having high serum IgE level. Analysis of the data demonstrated that 3/4 th of the patients had LPCR.33.8% developed only LPCR and 41.5% also had Immediate reactions, 17% of the patients developed only immediate reactions, whereas 8% were non reactive to any of the antigens. Serum immunoglobulin levels are not significantly different from that in patients with immediate reactions. There was no significant elevation of C-reactive proteins. The leukocyte migration inhibition test was negative in the majority. The relationship of LPCR to immediate hypersensitivity is discussed.