F Martinez-Alzamora | PubMed Health

PubMed1993

Sulfite-induced urticaria.

Metabisulfite sensitivity is being described with growing frequency. Sulfites are used in food, drinks, and drugs. Adverse reactions to apparently nontoxic doses have been described. Exposure of sensitive persons to sulfites has produced asthma, and occasionally other adverse reactions in nonasthmatic patients. We present a case of urticaria induced by metabisulfites. During the previous 2 years the patient had suffered episodes of urticaria and angioedema limited to the face, neck, upper thorax, and dysphonia without asthma after the ingestion of food and drinks containing sulfites. Oral challenge with 25 mg of potassium metabisulfite elicited urticaria on the face and neck, nasal itching, rhinorrhea, and dysphonia. Prick and intradermal tests were negative. Two further challenges with the same doses were also positive. One of these was controlled with placebo, 30 minutes after oral administration of 400 mg sodium cromolyn; the second was carried out 90 minutes after oral administration of 5000 micrograms cyanocobalamin. We have been unable to identify a pathogenic mechanism.

Adult↗

PubMedDate not supplied

Booster responses in the study of allergic reactions to beta-lactam antibiotics.

The observation of negative skin and challenge tests to beta-lactams in some patients with prior histories of reactions to these antibiotics led us to develop a protocol ("booster study") which systematically included the performance of skin and challenge tests to beta-lactams ten to thirty days after the study to confirm the negative results. From a total of 430 patients who came to our outpatient clinic because of a reaction to a beta-lactam or unknown antibiotic, 249 completed the study. Out of the patients who completed the second phase, or "booster study," the results were positive in the first phase, or conventional study in 42 patients, and negative in 207. The booster study was negative in 197 patients (95 percent) and positive in ten patients (5 percent). Skin tests were positive in 5 of them (penicilloyl-polylysine: 5; benzylpenicillin: 3; amoxicillin: 2; minor determinant mixture: 1), and 5 patients developed an allergic reaction after rechallenge (benzylpenicillin: 4; amoxicillin: 1). One patient with both negative skin tests and amoxicillin oral challenge in the booster study developed an immediate generalized urticaria with the oral intake of amoxicillin one month later at home; skin tests became positive at that moment. The negative results in the first phase of the study and the development of positive results in the second phase could be due to the existence of an immunological amnestic reaction or to sensitization after reexposure to beta-lactams in the diagnostic procedures.

Adolescent↗