A case of type I cryoglobulinaemia vasculitis associated with monoclonal gammopathy of undetermined significance exacerbated by a progression to multiple myeloma

摘要

A previously healthy 39-year-old lady presented with episodes of painful skin rashes involving both upper and lower limbs, including the soles of the feet in May 2016. The rashes were aggravated by cold weather. A few weeks later, she developed blistering and purpuric rashes, followed by bluish discolouration of both lower limbs which progressed rapidly, leading to bilateral lower limb acute ischaemia which required bilateral above-knee amputations. Histopathological examination of both femoral arteries showed organization and neovascularization of thrombus. Skin biopsy showed neutrophilic infiltration surrounding blood vessels and subcutaneous tissue, with occasional thrombi seen in the small vessels. Immunofluorescent staining did not show deposition of complement 3, IgG, IgA or IgM. Cryoglobulin detection test was positive. Rheumatoid factor, antinuclear antibody, anti-neutrophilic cytoplasmic antibodies, lupus anticoagulant, hepatitis B and hepatitis C serology were negative. Complement 3 and 4 levels were normal. Serum protein electrophoresis and immunofixation studies showed IgG-Kappa paraproteinaemia of 9.2 g/dl. Bone marrow examination showed < 10 clonal plasma cells, suggestive of monoclonal gammopathy of undetermined significance (MGUS). She was diagnosed with MGUS-related cryoglobulinaemia vasculitis (CV). Her symptoms markedly improved after treatment with glucocorticoids.