Erythroderma from systemic contact dermatitis: a complication of systemic gentamicin in a patient with contact allergy to neomycin.

A patient who was sensitive to potassium dichromate and neomycin showed a universal exfoliative erythroderma following intravenous gentamicin therapy. When his ear canals were later treated with a neomycin-containing topical medication, he reacted so severely that the skin of his ears was temporarily depigmented. Withdrawal of aminoglycoside antibiotics along with use of a topical steroid preparation under occlusion brought the eruption under control. Since approximately half of the persons with contact allergy to neomycin will also react to gentamicin, it seems unwise to treat such patients with other intravenous aminoglycosides that are closely related chemically. In our patient, multiple patch tests to other aminoglycosides caused positive reactions to all reagents containing a deoxystreptamine ring, but there was no reaction to streptomycin, which lacks that structure.