Lichen myxoedematosus

Lichen Myxoedematosus Lichen myxoedematosus, also known as papular mucinosis, is a rare skin disorder characterized by the accumulation of mucin in the skin. This condition is part of a spectrum of disorders known as mucinoses, which involve the deposition of mucin, a gelatinous substance, in the skin and other tissues.

Clinical Presentation

Lichen myxoedematosus is typically divided into two main forms: the generalized form, known as scleromyxedema, and the localized form. The localized form is further subdivided into discrete papular lichen myxoedematosus, acral persistent papular mucinosis, and nodular lichen myxoedematosus.

Generalized Form: Scleromyxedema

Scleromyxedema is characterized by widespread papules and sclerodermoid changes in the skin. Patients may also experience systemic symptoms such as fever, malaise, and muscle weakness. Scleromyxedema is often associated with a monoclonal gammopathy, particularly IgG lambda.

Localized Forms

• Discrete Papular Lichen Myxoedematosus: This form presents with small, firm papules that are usually confined to a limited area of the body.
• Acral Persistent Papular Mucinosis: This variant is characterized by papules located on the hands and feet.
• Nodular Lichen Myxoedematosus: This rare form presents with nodules rather than papules.

Pathophysiology

The exact cause of lichen myxoedematosus is unknown, but it is believed to involve an overproduction of mucin by fibroblasts in the skin. The condition is often associated with a monoclonal gammopathy, suggesting a possible link to plasma cell dyscrasias.

Diagnosis

Diagnosis of lichen myxoedematosus is based on clinical examination and histopathological findings. A skin biopsy typically shows increased mucin deposition in the dermis, along with fibroblast proliferation.

Treatment

Treatment options for lichen myxoedematosus are limited and often unsatisfactory. Therapies that have been tried include systemic corticosteroids, immunosuppressive agents, and intravenous immunoglobulin (IVIG). In some cases, treatment of an associated monoclonal gammopathy may lead to improvement in skin symptoms.

Prognosis

The prognosis of lichen myxoedematosus varies depending on the form and severity of the disease. Localized forms tend to have a better prognosis, while scleromyxedema can be associated with significant morbidity and mortality due to systemic involvement.

See Also

• Mucinoses
• Scleromyxedema
• Monoclonal gammopathy

External Links

• [Link to a relevant medical resource]

NIH genetic and rare disease info

• NIH info on Lichen myxoedematosus

Lichen myxoedematosus is a rare disease.