A case of cutaneous mucormycosis in Shanghai, China

A 34-year-old female farmer suffered from localized cutaneous mucormycosis for 17 years. At the first admission, the lesion was a dull red plaque, about 7 x 9 cm in size with ulcerations, surrounded by some nodules on the dorsum of her right hand. General examination did not reveal abnormal findings except the skin lesion. Direct examination of skin scrapings in 10% KOH revealed broad, sparsely septate, branching hyphae. Histopathology showed many intradermal granulomata and microabscesses as well as mycelial elements comprising broad, distorted, ribbon-like strands. Some of them were phagocytized by multi-nucleated giant cells. Cultures revealed rapidly growing yellow colonies on Sabouraud dextrose agar medium at 25 degrees C. Sporangiophores branched in sympodia and the sporangia were globose, 35-60 microns in diameter. Their walls were deliquescent, but some of them were rather persistent. Columellae were mostly globose, 12-17 microns in diameter, up to 35 microns with collars. Sporangiospores were mainly ellipsoidal, 1.5-2.5 x 3-5 microns in size, but sometimes highly variable in size and shape. The maximum growth temperature of the isolate was 37 degrees C. The pathogenic organism isolated was tentatively identified as Mucor lusitanicus, which, as far as we know, has not been reported as a causative agent of cutaneous mucormycosis.