Immunotherapy-refractory vacuolar myopathy with mucin deposition in scleromyxedema: A possible role of fibroblast growth factor 2.

Scleromyxedema (SME) is characterized by widespread waxy papules on the skin, with mucin deposits in the upper dermis. Twenty-one SME cases of myopathy have been reported; of the cases, six showed vacuolar formation, and two showed mucin deposition. We report the first case of SME with mucin-associated vacuolated fibers. A 45-year-old woman with SME developed progressive proximal muscle weakness. Muscle biopsy revealed myopathic changes with numerous vacuoles linked to mucin in the affected muscle fibers, which were heavily immunostained for fibroblast growth factor 2 (FGF2). Despite repeated high dose oral prednisolone and intravenous immunoglobulin administrations, muscle weakness recurred continuingly, culminating in death due to congestive heart failure. Immunotherapy was partly effective in our case, although it was refractory. Treatment responsiveness in patients with SME myopathy varied; however, due to its rarity, the mechanism remains to be elucidated. To address this issue, we investigated muscle specimens immunohistochemically and detected marked upregulation of FGF2 in the affected muscle fibers of our patient. FGF2, a strong myogenesis inhibitor, may exert a suppressive effect on muscle fiber regeneration, which may have conferred refractoriness to our patient's SME myopathy.

Clinical and Molecular Phenotyping in Scleromyxedema Pretreatment and Posttreatment With Intravenous Immunoglobulin.

OBJECTIVE: Scleromyxedema (SMX) is a rare systemic sclerosis mimic that often responds to intravenous immunoglobulin (IVIG) therapy, yet the resulting clinical and biochemical changes have not been well characterized. To better understand the pathogenesis of the disease and the efficacy of IVIG, we sought to explore whether IVIG would introduce a measurable biologic effect corresponding with clinical improvement. METHODS: Fifteen patients with SMX were recruited for the study. Clinical information and peripheral blood mononuclear cells for flow cytometry were obtained immediately before and again 1-2 weeks after patients received IVIG therapy. Ten patients also underwent skin biopsies for gene expression analysis both before and after IVIG therapy. Clinical data included measures of skin involvement (modification of the modified Rodnan skin thickness score [MMRSS] and percentage of body surface area) and several patient-reported outcome measures assessing patients' skin. RESULTS: Posttreatment, the average MMRSS score decreased from mean ± SD 13.6 ± 2.6 to 10.3 ± 1.9; P = 0.003. There were also significant improvements in skin flexibility (mean ± SD 5.4 ± 0.8 to 3.2 ± 0.7; P = 0.003) and softening (mean ± SD 4.9 ± 0.9 to 2.6 ± 0.6; P = 0.022). Baseline levels of Tc17 cells (CD8+CCR6+CXCR3+CCR4-) correlated with the extent of skin involvement as measured by MMRSS pretreatment (r = 0.69, P = 0.012) and decreased after IVIG therapy (mean ± SD 3.4% ± 3.2% to 1.3% ± 1.7%; P = 0.008). Posttreatment analysis of RNA in skin tissue revealed a decrease in gene expression of transforming growth factor ß (TGFß) cytokines as well as several interferon-inducible proteins. CONCLUSION: This open-label study further supports the evidence that patients with SMX respond both objectively and subjectively to IVIG therapy. Biologic studies suggest a role for T lymphocytes in the pathogenesis of the disease and reveal the potential significance of TGFß and interferon pathways.

Localized Lichen Myxedematosus With Plasma Cell Light Chain Restriction: Is It the Exception or the Rule?

Lichen myxedematosus is a chronic cutaneous mucinosis that can present on a spectrum from localized cutaneous lesions to systemic disease of scleromyxedema. The clinical presentation of localized cutaneous lichen myxedematosus is waxy lichenoid papules, nodules, and/or plaques that have histopathologic findings of mucin deposition and a variable degree of fibroblast proliferation. There is an absence of serum paraproteins, and there are no other systemic causes of cutaneous mucinosis such as thyroid disease. The pathogenesis of lichen myxedematosus is unknown. We report 3 cases of localized cutaneous lichen myxedematosus with a light chain-restricted plasmacytic component by in situ hybridization. Our findings deliver an insight for disease pathogenesis and highlight for the first time, the significance of plasma cells in lesions of localized cutaneous lichen myxedematosus. We suggest that plasma cell light chain restriction could represent a clue to distinguish localized cutaneous disease from systemic disease.

[Scleromyxedema as a systemic disease of glycosaminoglycan accumulation]. / Skleromiksedema kak sistemnaia bolezn' nakopleniia glikozaminoglikanov.

Scleromyxedema is a rare mucinosis with a primary skin lesion due to diffuse mucin deposition, sclerosis, and lichenoid eruptions in the absence of hypothyroidism. The paper describes scleromyxedema cases and gives recommendations for the histological diagnosis of the disease by histochemical reactions to detect acid and neutral glycosaminoglycans.

Frequency of cutis laxa-like clinical features and elastolysis in scleromyxedema: a retrospective clinicopathologic study of 19 patients with scleromyxedema.

BACKGROUND: Cutis laxa-like features were observed in a subset of patients with scleromyxedema. Given this observation, clinical and histopathologic features of scleromyxedema were reviewed in correlation with elastic tissue staining. METHODS: We retrospectively reviewed clinical records and histopathologic features from patients with scleromyxedema seen at our institution from 1992 through 2013. We also evaluated available skin biopsies with an elastin stain and assessed whether dermal elastin fibers were diminished in density or were fragmented (or both). RESULTS: Nineteen patients with scleromyxedema and 34 skin biopsies were identified. Alcian blue (mucin) stain was used to grade mucin deposition as weakly positive (24%), positive (44%) and markedly positive (32%). Eight patients (42%) had clinical findings of cutis laxa, which were often observed in conjunction with areas of papular eruption or induration. Elastic tissue fibers were normal in 9 of 34 skin specimens (26%), 18 of 34 specimens (53%) had diminished elastic fiber density and 7 of 34 (21%) had markedly decreased density. The elastic tissue was fragmented in 25 specimens (74%). CONCLUSIONS: A cutis laxa-like clinical presentation and decreased elastic tissue density on skin biopsy were consistent findings. Dermatologists and dermatopathologists should be aware of these previously unreported clinical and histopathologic findings.

Scleromyxedema and the dermato-neuro syndrome: case report and review of the literature.

Scleromyxedema is a generalized form of lichen myxedematosus which is characterized by a papular and sclerodermoid skin eruption resulting from dermal fibroblast proliferation and mucin deposition. The majority of patients with scleromyxedema have a monoclonal gammopathy, and other systemic manifestations are common. Herein we describe a case of the 'dermato-neuro syndrome', a rare and sometimes fatal neurologic manifestation of scleromyxedema which consists of fever, convulsions and coma, often preceded by a flu-like prodrome. In addition, we provide a comprehensive summary of previously published cases of the dermato-neuro syndrome and discuss the current etiopathogenic theories and treatment options for this rare disease.

Identification of specific chondroitin sulfate species in cutaneous autoimmune disease.

Cutaneous lupus erythematosus and dermatomyositis (DM) are chronic inflammatory diseases of the skin with accumulated dermal mucin. Earlier work has shown chondroitin sulfate (CS) accumulation within the dermis of discoid lupus erythematosus (DLE), subacute cutaneous lupus erythematosus (SCLE), and DM lesions compared with control skin. Immunohistochemistry for C4S revealed a greater density in DLE and DM lesions, whereas SCLE lesions did not differ from controls. Scleredema and scleromyxedema are attributed to increased hyaluronic acid, and lesional samples from these diseases also demonstrated accumulated dermal C4S. Interferon-γ and interleukin-1α, but not interferon-α, treatment of cultured dermal fibroblasts induced mRNA expression of CHST-11, which attaches sulfates to the 4-position of unsulfated chondroitin. These studies on possible CS core proteins revealed that serglycin, known to have C6S side chains in endothelial cells, had greater density within DM dermal endothelia but not in DLE or SCLE, following the pattern of C6S overexpression reported previously. CD44 variants expand the CS binding repertoire of the glycoprotein; CD44v7 co-localized to the distribution of C4S in DLE lesions, a finding not observed in DM, SCLE lesions, or controls. Because C4S and C6S have immunologic effects, their dysregulation in cutaneous mucinoses may contribute to the pathogenesis of these disorders.

Scleroderma renal crisis-like acute renal failure associated with mucopolysaccharide accumulation in renal vessels in a patient with scleromyxedema.

Scleromyxedema is a systemic disease characterized by lichenoid papules, nodules, and plaques on the skin and often diffuse skin induration resembling the cutaneous involvement of systemic sclerosis. The systemic involvement affects the musculoskeletal, pulmonary, cardiovascular, gastrointestinal, and central nervous systems, and the disorder is commonly associated with a paraproteinemia. Involvement of the kidney is rare and not considered a feature of the disease. Here, we describe an unusual case of scleromyxedema complicated by the development of scleroderma renal crisis-like acute renal failure with a marked intimal deposition of mucin, mucopolysaccharides, and hyaluronic acid in the intrarenal vessels.