A rare case of acute generalized exanthematous pustulosis induced by gadobutrol

Abstract

favour of CL as vacuoles in suprabasal keratinocytes and degeneration in basal keratinocytes which are common biopsy features of vitiligo were not seen in our case. Diagnosis of CL was made based on the clinical findings and patch test.p-phenylenediamine which is structurally similar to tyrosine competes with tyrosine for hydroxylation by tyrosinase and interferes with melanin synthesis. Similarly, tyrosinase-related protein 1 converts phenols and catechols into semiquinone free radicals and reactive oxygen species which causes oxidative stress on melanocytes, 2 which may lead to loss of melanocytes within the skin and hair follicle, resulting in skin depigmentation and greying of hair. 8 The above CL case is interesting as patch testing was strongly positive for contact allergy to p-phenylenediamine with depigmentation at the test site. 9 Literature search revealed only a few cases of CL at the test site for p-phenylenediamine. 10