[Inguinal mastocytosis with histiocytic infiltrate].

INTRODUCTION

The diagnosis of mastocytosis is usually not difficult in cases with typical skin lesions. Intertrigo is exceptional.

CASE REPORT: An 83-year-old patient developed inguinal intertrigo bilaterally. The lesions contained maculopapulous elements without Darier's sign. The histology examination revealed a mixed mast cell infiltration predominated by histiocytes. The ultrastructure confirmed the diagnosis of cutaneous mastocytosis. No extension was observed.

DISCUSSION: Skin folds are rarely involved in infiltrating diffuse mastocytosis. Two cases have been reported in the literature including one doubtful case. Mastocytosis should thus be included in the possible diagnoses in patients with macupopapulous intertrigo. In addition, the mastocytic and histiocytic polymorphism observed here is rare.