What is Multicentric Reticulohistiocytosis?

Multicentric Reticulohistiocytosis (MR, MRH, previously also called Lipoid dermatoarthritis) is a rare disease, primarily affecting patients in their adulthood characterized by the rapid appearance of multiple papules and nodules arising in conjunction with severe arthritis. The name was first proposed in 1954 by Goltz and Laymon. MRH is very rare. The average dermatologist, rheumatologist, or orthopedist will see at most 1-2 cases in an entire career. MRH may become inactive after several years, often after about 8 years. In about 28% of cases, the disease appears to be related to an underlying malignancy. MRH precedes the development of cancer in 73% of cases. No therapy consistently improves MRH. The response to therapy is difficult to determine because of the rarity of the disease and the lack of controlled studies.