MULTIPLE KERATOAOANTHOMAS (WITTEN-ZAK TYPE) IN PRURIGO SIMPLEX SUBACUTA

We report on the case of a 51-year-old female patient who had been suffering from multiple itching nodules for 3 years. Some of these lesions were classified clinically and histologically as keratoacanthomas (KA), whereas the multiple smaller nodules were found on histological examination to be either early stage KA or lesions of prurigo simplex subacuta. In two KA, HPV subtype 2 was identified by in situ hybridization. Treatment with etretinate resulted in remission of the fully developed KA and reduced the occurrence of new ones. The outbreak of multiple KA in our patient resembled a rare subtype described by Witten and Zak. Postclinical follow-up for 28 months to date has revealed that the KA arise from the subacute prurigo lesions. This mode of prurigo-dependent KA development has not previously been reported.