Prevalence and relevance of allergic reactions in patients patch tested in North America--1984 to 1985.

Between Jan. 1, 1984, and May 1, 1985, 1199 patients with suspected allergic contact dermatitis were patch tested with 32 "standard" allergens, 707 patients with 19 "vehicle and preservative" allergens, and 613 patients with 10 "special study" allergens. Ten dermatologists representing nine geographic centers collected and analyzed data with the use of the American Academy of Dermatology's mainframe computer in Evanston, Illinois. The most common sensitizers identified were nickel, p-phenylenediamine, quaternium-15, neomycin, thimerosal, formaldehyde, cinnamic aldehyde, ethylenediamine, potassium dichromate, and thiuram mix. Each positive reaction was assessed for its clinical relevance.

Eosinophilic cellulitis (Wells' syndrome): histologic and clinical features in arthropod bite reactions.

Five patients are described with the clinical and histopathologic picture, including flame figures, of eosinophilic cellulitis (Wells' syndrome). Two of them had documented tick bites in the center of these expanding annular lesions, and the histologic picture showed the diagnostic flame figures of Wells' syndrome (eosinophilic cellulitis). A third patient had a clinical picture suggestive of a tick bite reaction but stated she was stung by a small garden bee at the involved site. The fourth patient removed a spider from the site of a spider bite, and this nodule also histopathologically was identical to that of eosinophilic cellulitis. Our fifth patient presented with papular urticaria of flea bites. We suggest that the characteristic flame figures of eosinophilic cellulitis (Wells' syndrome) are not diagnostic of a specific disease entity but rather a striking and peculiar histopathologic response to multiple factors of which arthropod bites (ticks, bees, fleas, and spiders) represent one definite etiology.

Relapsing polychondritis: unusual neurological findings and therapeutic efficacy of dapsone.

Relapsing polychondritis is a rare disease of undetermined cause. The most frequently seen symptom is redness and swelling of the cartilaginous ear, followed by cartilage inflammation elsewhere in the body. Our five cases had neurologic symptoms that posed diagnostic difficulties. Because vasculitis is not uncommon in relapsing polychondritis, it was difficult to determine whether these neurologic symptoms were attributable to relapsing polychondritis or to other unrelated causes. In our cases, specific neurologic complaints were caused by a concomitant but unrelated disease, rather than by relapsing polychondritis. We add five additional documented cases to the medical literature and confirm the therapeutic efficacy of dapsone in the treatment of this unusual disease.

Tobramycin-neomycin cross-sensitivity.

Fifty normal control volunteers were patch tested to 20% neomycin as well as tobramycin 1%, 10%, 20% and 30% in white petrolatum. Tobramycin is a new aminoglycoside antibiotic for prescription ophthalmologic use in the United States. There were no reactions on any of the control volunteers. Twenty known and proven neomycin-allergic patients were then tested to tobramycin 10% and 20% in white petrolatum, as well as to neomycin 20% aqueous and 20% in white petrolatum. All 20 reacted with a 2+ or greater response to the neomycin patch tests. Twelve out of the 20 or 60% of the neomycin-allergic patients reacted to the 10% tobramycin in white petrolatum. Thirteen out of 20 or 65% reacted to 20% tobramycin in white petrolatum. From these data, tobramycin (ophthalmic) should not be used to treat known neomycin-allergic patients without first patch testing the patient with 20% tobramycin in white petrolatum. It appears probable that 65% of neomycin-allergic patients would react with a dermatitic response to such therapy.

Cinnamic aldehyde allergy.

Positive patch test reactions to 2% cinnamic aldehyde were obtained from 2.8% of 34 males and 9.1% of 55 females. The 9.1% female reactivity may be traceable to perfumed cosmetics. Simultaneous Jasmin allergy is documented as is the occurrence of alpha-amyl cinnamic aldehyde in synthetic Jasmin. The relevance of these reactions is discussed. In two of the patients a proper diagnosis was not made from the original contact history. Only after a screening tray demonstration of cinnamic aldehyde allergy could a relevant history be taken from these patients.