Extensive hyperpigmented plaques in a chinese singaporean woman: a case of cutaneous plasmacytosis.
Cutaneous plasmacytosis is a rare disease entity presenting with multiple extensive red-brown plaques, histopathology showing marked hyperplasia of mature polyclonal plasma cells, and polyclonal hypergammaglobulinemia on serum protein electrophoresis, in the absence of an underlying secondary cause. We report in this article the first case of cutaneous plasmacytosis from Singapore. A 33-year-old Chinese woman presented with mildly pruritic reddish brown papules and plaques over her trunk and arms for 2 years. Physical examination, laboratory investigations, and radiographic examination were negative for systemic involvement and lymphadenopathy. Serum immunoelectrophoresis showed polyclonal hypergammaglobulinemia with immunoglobulin G and immunoglobulin A. Two sets of skin biopsies performed 2 years apart essentially showed similar histopathological findings of a superficial and deep perivascular infiltrate with numerous mature plasma cells and small typical lymphocytes. There were lymphoid follicles with well-formed germinal centers and mantle zones, surrounded by mature lymphocytes. No light chain restriction was present on immunohistochemistry, and polymerase chain reaction for heavy chain gene rearrangement was negative for monoclonality. Despite potent topical corticosteroids and 8 months of phototherapy with narrow band ultraviolet light, there was no improvement. Intralesional triamcinolone injections to a few lesions afforded temporary relief of itch and flattening of lesions.
Department of Dermatology, National Skin Centre, Singapore. joycelee@nsc.gov.sg
Joyce Ss
JS
Lee
Lynn
L
Chiam
Kong Bing
KB
Tan
Manuel
M
Salto-Tellez
Suat Hoon
SH
Tan
Beng Hock
BH
Ong
See Ket
SK
Ng
D000328:Adult; D005260:Female; D006801:Humans; D006942:Hypergammaglobulinemia / Q000209:etiology; D017495:Hyperpigmentation / Q000150:complications / Q000473:pathology*; D010950:Plasma Cells / Q000473:pathology*; D012846:Singapore; D012871:Skin Diseases / Q000150:complications / Q000473:pathology*