Intralymphatic histiocytosis with granuloma formation associated with orthopaedic metal implants.

Abstract

A 75-year-old man presented with a 1-year history of asymptomatic reddish-brown nodules on his left knee, in which orthopaedic metal implants had been inserted for a transformation-related knee joint disorder. Histopathological examination revealed typical features of mixed cell granuloma with many dilated lymphatics that contained many histiocytes from the upper dermis to subcutaneous fat tissue. Results of qualitative analysis of biopsy specimens by energy-dispersive X-ray spectroscopy were positive for molybdenum, which was one of the constituents of the metal implant. We describe the first observation of intralymphatic histiocytosis with granuloma formation in the skin occurring in a patient bearing orthopaedic metal implants for a transformation-related knee joint disorder.