muramidase and Urticaria

We occasionally see egg-allergic children who develop contact urticaria to hen's egg despite the absence of the overt symptoms on ingestion. The mechanisms remain to be elucidated.. Twenty-one subjects with positive reactions to 20-min patch tests for egg-white antigens were divided into subgroups with positive (n = 10) and negative (n = 11) results to oral challenge tests by the same antigens. We measured IgE antibody for egg white and its components, and IgE-binding activities to digestive enzyme-treated ovomucoid by RAST inhibition.. There were no significant differences in IgE antibody titers to egg white (positive vs negative: 30.3% vs 15.3%, P=0.130), ovomucoid (21.5% vs 10.2%, P= 0.078), ovotransferrin (9.9% vs 3.7%, P = 0.105), and lysozyme (3.4% vs 2.9%, P=0.944), except ovalbumin (16.8% vs 5.6%, P=0.024), between the positive and negative subjects in the provocation tests. In contrast, the concentration (1.93 microg/ml) of pepsin-treated ovomucoid needed for 50% RAST inhibition in the challenge-positive subjects was significantly (P=0.0003) lower than that (114.9 microg/ml) of negative subjects. Similar but less significant differences were obtained when ovomucoid fragments treated with chymotrypsin (0.91 microg/ml vs 6.86 microg/ml, P=0.014) and trypsin (0.75 microg/ml vs 4.67 microg/ml, P= 0.041) were used as inhibitors.. We suggest that IgE antibodies from subjects showing contact urticaria despite the absence of reactions to the ingestion of egg white recognize the epitope(s) unstable to digestive enzymes.

Topics: Administration, Oral; Allergens; Animals; Child; Child, Preschool; Chymotrypsin; Conalbumin; Double-Blind Method; Egg White; Eggs; Female; Food Hypersensitivity; Humans; Immunoglobulin E; Infant; Male; Muramidase; Ovalbumin; Ovomucin; Pepsin A; Placebos; Radioallergosorbent Test; Trypsin; Urticaria

We report a case of toxic epidermal necrolysis-type drug eruption. A 23-year-old man took an oral over-the-counter preparation for the common cold. A few days later, generalized erythema developed with systemic malaise and pain. A multiple blister formation followed, and Nikolsky's sign was noted on each blister. A lymphocyte stimulation test (LST) with the patient's peripheral lymphocytes strongly suggested that the eruption was attributable to lysozyme chloride which was included in the preparation taken. Following an intravenous drip of betamethasone for two weeks, the eruptions improved favorably.

Topics: Acetaminophen; Administration, Oral; Adult; Anti-Inflammatory Agents; Betamethasone; Biopsy, Needle; Caffeine; Common Cold; Drug Combinations; Follow-Up Studies; Guaiacol; Humans; Male; Muramidase; Nonprescription Drugs; Stevens-Johnson Syndrome; Urticaria