Relative utility of skin prick tests, total IgE and allergen-specific IgE in allergy diagnosis

Abstract

Rationale The study assessed the correlation between skin prick test (SPT), determination of specific IgE antibodies and total serum IgE in patients with a history of allergic disorders. Methods 48 patients, 31 females and 17 males, age 16 to 65 years old were studied by SPT, total IgE and allergen-specific IgE. 27 patients had respiratory disorders, 15 had skin disorders and 6 had a history of systemic allergic reactions after insect stings. Results In 8 patients SPT and specific IgE were negative, 1 of whom had a slightly increased total IgE. In 8 patients SPT and specific IgE were positive, 4 of whom had increased total IgE. Among 10 patients who had dermographism and positive specific IgE, 6 had an elevated total IgE. 19 patients having negative SPTs had positive specific IgE assays, 9 also having a high level of total IgE. Conclusions There was no significant correlation between SPT and specific IgE tests, or between SPT and total serum IgE level. When SPT is positive and in agreement with the clinical history, the total and specific IgE add no additional useful information. However, in patients having dermographism or negative SPT, total and specific IgE determination may assist in confirmation of the diagnosis.