[Monoclonal immunoglobulin (M-Ig) and skin diseases from the group of mucinoses--scleredema adultorum Buschke and scleromyxedema. Description of four cases and an overview of therapies]

Abstract

Introduction: The mucinoses of the type of scleredema and scleromyxedema are diseases marked by excessive production of mucin deposits in the skin and subcutaneous tissue, which causes skin hardening. The skin and subcutaneous deposits hamper the movement of limbs, the thorax as well as mouth. The same mechanism also damages other organs (the heart, lungs, oesophagus). It is probably caused by the stimulation of mucin production in fibroblasts by immunoglobulins, frequently monoclonal immunoglobulin. Therefore these diseases are typically associated with monoclonal gammopathy.

Case reports: We describe a cohort of 4 patients, skin manifestations were twice identified as scleredema and twice as scleromyxedema. All the four patients had type IgG monoclonal immunoglobulin and had clonal plasma cells in the bone marrow proven by histologic examination and flow cytometry. Therefore we commenced chemotherapy in all of them. In one case this chemotherapy was ended by a high-dose chemotherapy with transplanting of autologous red blood cells. This therapy attained the complete disappearance of monoclonal immunoglobulin as well as cutaneous and extracutaneous manifestations of scleredema (obstipation). In one case chemotherapy led to partial hematologic remission and partial improvement of skin manifestations. The other two patients did not respond to standard chemotherapy. The condition of one of them resulted in dermato-neuro syndrome (confusion, somnolence passing into coma and grand mal seizure) and improved following an intensive treatment including also intravenous application of immunoglobulins in a dose of 2 g/per 1 kg weight. This patient has now been under long-term treatment with these immunoglobulins, during which the skin symptoms have significantly diminished, but the concentration of monoclonal immunoglobulin has not changed. The fourth patient not responding to standard chemotherapy was treated with intravenous immunoglobulins also in a dose of 2 g/per 1 kg of weight 1× in a month. After 4 applications the thickening of skin and subcutaneous tissue moderately diminished, so the range of possible movement of the upper limbs and neck became larger and the itchy skin morphs which accompanied the disease disappeared completely.

Conclusion: It is possible to use chemotherapy and high-dose chemotherapy in the treatment of mucinosis associated with monoclonal gammopathy, as in the treatment of multiple myeloma. If such treatment is not possible or it has not attained disappearance of monoclonal immunoglobulin, improvement can be achieved through repeated application of intravenous immunoglobulins. The treatment with intravenous immunoglobulins in an immunomodulation dose of 2 g/per 1 kg of weight effects the moderation of skin manifestations, but it does not lead to the decrease in monoclonal immunoglobulin.