[Penicillin allergy as a diagnostic problem. Overview and personal studies].
OBJECTIVE
Penicillin allergy is a common clinical problem. The distinction between penicillin and para-infectious exanthems is difficult. We investigated the reliability of the history, as well as the sensitivity and specificity of skin tests and specific IgE levels.


METHODS
160 patients with a history of penicillin allergy were retrospectively evaluated in the outpatient department of a dermatological clinic.


RESULTS
Nearly 50% were diagnosed as allergic to penicillin by detection of specific IgE or skin test. About 60% of the patients with immediate type reactions, and 72% with maculo-papular erythema showed positive reactions in skin tests. Significantly more patients were diagnosed as allergic to penicillin by intradermal testing than by prick testing (p < 0.05). The sensitivity of the specific IgE RAST was 17.9%; the specifity, 89.5%. For the prick test the sensitivity was 8.2%; the specificity 90.8%. For the intradermal test the sensitivity was 26%; the specifity 69.7%.


CONCLUSIONS
We suggest a step by step procedure to detect penicillin allergy making the diagnostic results as valid as possible.
Walker
T
T
Hautklinik, Klinikum Mannheim gGmbH, Universitätsklinikum, Fakultät für Klinische Medizin Mannheim, Universität Heidelberg.
Jung
E G
EG
Bayerl
C
C
D000918:Antibody Specificity / Q000276:immunology; D003937:Diagnosis, Differential; D003875:Drug Eruptions / Q000175:diagnosis* / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007428:Intradermal Tests; D010328:Patch Tests; D010406:Penicillins / Q000009:adverse effects* / Q000276:immunology; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
D010406:Penicillins; D007073:Immunoglobulin E