Diagnosis: Multicentric reticulohistiocytosis (MRH).
MICROSCOPIC, RADIOLOGIC, AND LABORATORY FINDINGS AND CLINICAL COURSE
The histologic sections showed a nodular lesion with a hyperkeratotic epidermis. The dermis contained a diffuse infiltrate of histiocytes, lymphocytes, and occasional neutrophils. The key feature was of scattered multinucleate giant cells with a "ground glass" eosinophilic cytoplasm.
Radiographic evaluation of the knees confirmed joint effusions without evidence of joint destruction or erosions. Laboratory investigations showed high-titer gliadin IgA and tissue transglutaminase IgA antibodies consistent with celiac disease. Treatment was commenced with methotrexate.
DISCUSSION
Multicentric reticulohistiocytosis is a rare subgroup of the non-Langerhans cell histiocytoses first described by Weber and Freudenthal1 in 1937. In contrast to diffuse cutaneous reticulohistiocytosis and isolated reticulohistiocytomas, MRH is associated with a destructive arthritis. Typically, reticulohistiocytoses affect white adults at a mean age of 50 years, with pediatric cases rarely reported.2-4
Association with celiac disease has only been reported once previously to our knowledge, and the positive serologic findings in our case may further support reported . . . [Full Text of this Article]
