Multicentric Reticulohistiocytosis
David Cassarino, MD, PhD
Key Facts
Terminology
Giant cell reticulohistiocytosis
Clinical Issues
Most cases occur in adults > 40 years old
Multiple nodules and arthropathy
Prognosis is variable; some cutaneous lesions may regress
Osteoarticular involvement shows progressive course in 1/2 of cases
Microscopic Pathology
Dermal-based nodular proliferation of large mononuclear and multinucleated histiocytes
Often overlying epidermal atrophy
Cells show characteristic abundant glassy/hyalinized-appearing eosinophilic cytoplasm
Occasional Touton-type giant cells containing lipid may be present, but not prominent
Background of neutrophils and eosinophils
 Low magnification of MCR shows a nodular proliferation of enlarged histiocytic cells in the dermis. There is a very thin grenz zone  , and the epidermis shows flattening of the rete ridges. |
 Higher magnification of MCR shows a proliferation of numerous enlarged histiocytic-appearing cells  associated with a background mixed inflammatory infiltrate containing scattered eosinophils  . |
TERMINOLOGY
Abbreviations
Multicentric reticulohistiocytosis (MCR)
Synonyms
Giant cell reticulohistiocytosis
Reticulohistiocytosis of skin and synovia
Definitions
Proliferation of large histiocytes with dense eosinophilic cytoplasm involving multiple organs
ETIOLOGY/PATHOGENESIS
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
