An Interesting Case of Pyoderma Gangrenosum with Immature Hystiocytoid Neutrophils

Abstract

We present a unique case of a 36-year-old male who developed more than twenty Pyoderma gangrenosum ulcers demonstrating on histopathology a dense inflammatory infiltrate composed of histiocytoid mononuclear immature cells with a strong positivity for myeloperoxidase and Leder stain, suggesting a myeloid lineage in the absence of a concomitant myeloproliferative disorder. Histiocytoid Sweet syndrome is now recognized as a histological subtype of Sweet syndrome. Although Pyoderma gangrenosum and Sweet syndrome belong to the spectrum of neutrophilic diseases, to the best of our knowledge, this is the first case of a "Histiocytoid Pyoderma gangrenosum" encompassing immature granulocytes in the absence of leukemia cutis.