[Studies on the skin test of cefotiam and anti-cefotiam antibody]

Patients having previously not received cefotiam (CTM), a recently introduced cephem antibiotic, were subjected to skin tests with a 300 micrograms/ml solution of CTM in physiological saline before and after CTM therapy to detect sensitization with the drug. Anti-CTM antibody titration was carried out on sera from patients who showed a positive skin test and those who developed signs of hypersensitivity during CTM therapy. The results were as follows: Of 1,927 patients examined by skin test with CTM prior to initiation of CTM therapy, 31 patients (1.61%) showed positive reactions with formation of a wheal and erythema. There were 7 patients (0.36%) who proved negative in the skin test but developed mild symptoms of hypersensitivity in association with the skin test. The 847 patients negative on the CTM skin test were retested after a completion of CTM therapy, of whom 6 (0.71%) were found to have become positive showing formation of a wheal and erythema and 3 others (0.35%) showing a negative skin test developed mild adverse reactions associated with the skin test. Sixty-eight serum samples collected from the patients positive on the CTM skin test and those who developed manifestations of hypersensitivity following CTM therapy were examined for anti-CTM antibody by the Prausnitz-K ustner reaction, passive cutaneous anaphylaxis test and hemagglutination test. All proved negative in these tests. Of various background factors assessed, none was found to have causal relation to the skin reaction in any of the patients showing positive skin reactions to CTM.