Amicrobial pustulosis of the folds: Where have we gone 25 years after its original description?

Abstract

Twenty-five years ago at the Journées Dermatologiques de Paris, Prof. Béatrice Crickx described a new association, "antimicrobial pustulosis and systemic lupus erythematosus", a condition now known as amicrobial pustulosis of the folds (APF). The aim of this study is to analyse the clinical and laboratory characteristics of APF and to outline the gradual advancement of knowledge regarding this disease. Based on a case of APF seen in our department, we carried out a review of the literature since 1991 by searching the Medline database for scientific articles using the following keywords: "Amicrobial Pustulosis" or "Pustular Dermatosis" and "Folds". We collated 63 cases of APF. In total, 90% involved women and the mean age was 30 years. Cutaneous lesions consisted of pustules in an erythematous setting, frequently erosive and affecting the skinfolds, anogenital region, scalp, external auditory meatus and umbilicus. Histological examination revealed spongiform subcorneal pustulosis associated with mixed inflammatory infiltrate in the dermis. APF belongs to the spectrum of neutrophilic dermatoses. Its complex physiopathology involves an auto-inflammatory mechanism. It is associated with a variety of autoimmune diseases, in most cases systemic lupus erythematosus. Diagnosis of the condition is difficult and is based on histological correlation and negative microbiological culture. The most effective treatment is still systemic corticosteroids, although new therapeutic alternatives are emerging such as anakinra and anti-TNF-alpha drugs.