Resident Rounds. Part III: Multicentric Reticulohistiocytosis Presenting as Granuloma Annulare

December 2012 | Volume 11 | Issue 12 | Features | 1509 | Copyright © December 2012

Heather Kiraly Orkwis DO, Craig Cattell MD, and Jessica Ghaferi MD

Abstract

CASE REPORT

A 56-year-old female presented with a 6-month history of asymptomatic red plaques on her hands. She had an underlying history of arthritis in her hands and feet. She was initially treated for granuloma annulare with topical steroids, but no improvement was noted.
Examination of the bilateral dorsal hands showed multiple violaceous plaques, some with an annular appearance (Figures 1 and 2). No nail involvement was noted.
Complete blood cell count, rheumatoid factor assay, and serum protein electrophoresis were within normal limits. Lipid concentration panel showed hypercholesterolemia. Radiographs of the bilateral hands revealed narrowing of the proximal and distal interphalangeal joint spaces.

Microscopic Findings

Biopsy showed a dermal lymphohistiocytic infiltrate with prominent multinucleated giant cells containing abundant eosinophilic cytoplasm (Figure 3).

DISCUSSION

Multicentric reticulohistiocytosis (MRH) is a rare histiocytic proliferative disease with unknown etiology. MRH features widespread cutaneous disease along with a destructive arthritis, typically presenting in females in the fifth or sixth decade of life. A classic nail finding is the "coral bead sign," where multiple small papules trail along the nail fold.
The polyarthritis is diffuse, symmetric, progressive, and destructive of the articular cartilage and subarticular bone. There is a predilection for the distal interphalangeal joints. The associated arthritis is caused by the same type of infiltrate as is found in the cutaneous lesions.
Additional systemic associations include hyperlipidemia (30%-50%), internal malignancy (15%-30%),1 and autoimmune disease (5%-15%). MRH precedes the diagnosis of malignancy in 75% of cases.2
Histopathologically, MRH is similar to giant cell reticulohistiocytoma.3 Both have numerous multinucleate giant cells and oncocytic macrophages showing abundant eosinophilic fine, grainy cytoplasm, which has the characteristic "ground glass"
table 1