Scleromyxedema Clinically Resembling to Scleroderma.

Sir

Scleromyxedema is characterized by papules with dermal fibroblast proliferation and mucinous deposits,[1] and associated with monoclonal M proteinemia or paraproteinemia. We report a 61-year-old man with scleromyxedema associated with multiple myeloma. He had a 2-year history of progressive thickening of both hands. One year earlier a diagnosis of multiple myeloma IgG λ type was made elsewhere and he underwent observation therapy only. He was referred to us with inability to fully flex his fingers [Figure 1a]. Physical examination revealed diffusely sclerotic skin on both hands and all fingers but no nail fold bleeding, telangiectasia, pitting ulcers on his fingertips, or Raynaud's phenomenon. Histology demonstrated typical myxoid deposits in the upper dermis and increased and dense collagen bundles [Figure 1b]. Colloidal iron staining confirmed mucin in the entire dermis [Figure 1c]. The collagen bundles were split into individual fibers by mucin. Congo red and direct-fast-scarlet staining showed no amyloid deposits. Anti-nuclear-, anti-centromere, anti-Scl-70, and anti-U1 RNP antibodies were negative. His white- and red blood cell- and his platelet count was 5.69 × 103 /μL, 3.43 × 106 /μL, and 1.93 × 105 /μL, respectively. Total serum protein was 8.5 g/dl with 3.2 g/dl (37.2%) g-globulin. Serum IgG, -A, and -M was 3267-, 22-, and 21 mg/dl, respectively. Serum immunofixation electrophoresis revealed IgG monoclonal gammopathy, and urine immunofixation electrophoresis revealed IgG λ type Bence-Jones proteinuria; bone marrow biopsy revealed plasmacytosis. There were no osteolytic lesions. Although no characteristic waxy papules were found, we made a diagnosis of scleromyxedema associated with multiple myeloma.

Figure 1

(a) Thickening of both hands; Raynaud's phenomenon and telangiectasia are absent (b) Extensive mucin deposition in the upper dermis, increased collagen production, and proliferation of fibroblasts. Collagen bundles are split into individual fibers by mucin. (H and E, ×100) (c) Colloidal iron staining revealed mucin in the entire dermis (×100)

Scleromyxedema presents with 2-4 mm waxy papules distributed symmetrically on the arms, hands, and face.[2] It is differentiated from scleroderma by the papular component and the absence of teleangiectasia.[3] Our patient exhibited atypical scleromyxedema. We attribute the absence of papular eruptions to the homogeneous mucinous deposition in the entire dermis. Histological findings and the coexistence of paraproteinemia aided our diagnosis. Although its etiology remains unclear, scleromyxedema is frequently associated with paraproteinemia involving myeloma-like, homogenous serum globulin of the IgG type with predominantly λ light chains.[1] No relationship was found between the paraprotein level and the extent of skin or internal organ involvement.[4] However, previous reports showed some benefit of melphalan, thalidomide, cyclophosphamide, and intravenous immunoglobulin for scleromyxedema, our patient received no specific treatment.

We suggest that scleromyxedema be considered although skin lesions are similar to scleroderma and without papules, especially in patients with paraproteinemia.