Delayed hypersensitivity to hydroxychloroquine manifested by two different types of cutaneous eruptions in the same patient

• Published in: Allergologia et immunopathologia Vol. 34; no. 4; p. 174
• Main Authors: Pérez-Ezquerra, P Rojas, de Barrio Fernández, M, de Castro Martínez, F J, Ruiz Hornillos, F J, Prieto García, A
• Format: Journal Article
• Language: English
• Published: Spain 01-07-2006
• Subjects: Biopsy; Dermatitis, Allergic Contact - etiology; Eczema - chemically induced; Erythema Multiforme - chemically induced; Exanthema - chemically induced; Female; Humans; Hydroxychloroquine - adverse effects; Middle Aged; Patch Tests; Pruritus - chemically induced; Skin - pathology; Spondylitis, Ankylosing - complications; Stomach Diseases - chemically induced
• ISSN: 0301-0546
• DOI: 10.1016/S0301-0546(06)73537-6

Hydroxychloroquine (HXQ) sulphate is a synthetic antimalaria drug that is widely used in rheumatology due to its immunosuppressive properties. Delayed-type sensitization to this drug is rare. A 47-year-old woman diagnosed with HLA B27 ankylosing spondylitis was treated with HXQ for 22 days and had to discontinue the drug due to gastric intolerance. Five days later the patient developed erythema multiforme (EM) with an extensive and unusual distribution. Patch test with 10% HXQ in DMSO were positive at 48 hours. Eight days later a generalized pruriginous erythematous papular exanthema developed, and a skin biopsy was obtained. The first reaction was EM. Patch-testing elicited systemic eczematous contact dermatitis. We report two different clinical patterns of delayed hypersensitivity in the same patient and with the same drug.