What Is Scleromyxedema?
Scleromyxedema is the generalized form of a condition called lichen myxedematosus. Lichen myxedematosus is a rare skin disorder characterized by mucin deposits in the skin, and it has localized and generalized forms. Scleromyxedema can involve other organs and can be fatal.
Scleromyxedema was first defined by Arndt and Gottron in 1954 and redefined by Rongioletti and Rebora in 2001. It is also known as Arndt Gottron syndrome or generalized lichen myxedematosus. It is mainly characterized by monoclonal gammopathy (presence of abnormal proteins in the blood), generalized papular and sclerodermoid eruption, and a triad of histologic features like the presence of mucin deposition in the dermis layer of skin, fibroblast (cells that maintain the framework of many tissues), and fibrosis with the absence of a thyroid disorder. This syndrome will have diffuse thickening of the skin below the papules.
The etiology of this condition remains unknown. It is a chronic progressive disorder and is associated with a systemic involvement that increases the severity of the disease. It is mainly found in the middle-aged, affecting both men and women. There is no standard treatment devised due to the rarity of the condition.
How Common Is Scleromyxedema?
This condition is a very rare skin disorder that is characterized by dysproteinemia (excessive production of immunoglobulin) and huge skin changes. Limited scleroderma is the most common form, where skin tightening and hardening occur only in a limited area such as fingers, hands, or face. In this form, internal organ damage is much less. The cause of this condition is unknown.
How Does Scleromyxedema Progress?
Scleromyxedema is a fatal condition. The initial stage of this condition involves excessive deposition of mucin in the connective tissue. These mucin depositions can stimulate the synthesis of collagen and glycosaminoglycans (a type of complex carbohydrate found on the cell surface). This leads to the formation of lichen papules that can lead to the thickening and hardening of the tissue. This condition can lead to muscular, neurologic, rheumatologic, pulmonary, renal, gastrointestinal, and cardiovascular involvement when it progresses. This can gradually lead to the death of the affected individual.
What Are the Stages of Scleromyxedema?
There are three stages proposed for this disease;
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Stage 1 - This stage is limited to cutaneous papular mucinosis (mucin deposition on the skin).
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Stage 2 - It is characterized by generalized cutaneous mucinosis or extracutaneous manifestations (systemic involvement).
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Stage 3 - It is characterized by generalized cutaneous mucinosis and extracutaneous manifestations, and Karnofsky performance (a tool for assessing functional impairment) is less than 50 %.
What Is the Etiology of Scleromyxedema?
The etiology of scleromyxedema remains unknown. However, this condition is often associated with conditions like myeloma (cancer of the plasma cells), leukemia (cancer of the blood cells), and lymphoma (cancer of the lymph system). There is no evidence that scleromyxedema is an inherited disorder.
What Are the Clinical Features of Scleromyxedema?
The main clinical features of scleromyxedema include the following:
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The skin has many linear folds and appears like elephant skin.
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The appearance of papules in the neck and forehead area. It usually occurs in a group.
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Muscle weakness.
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Decreased range of motion of face, fingers, and extremities.
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Difficulty in swallowing.
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Joint pain.
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Deposits in the cornea.
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Thinning of the eyelid.
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Migrating arthritis.
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Sclerodactyly (claw-like appearance of fingers due to hardening of the skin on the hand).
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Kidney problems.
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Heart problems like atherosclerosis (build-up of plaque in the arteries).
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Lung diseases.
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Encephalopathy (disease affecting the proper functioning of the brain).
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Coma.
How to Diagnose Scleromyxedema?
Scleromyxedema diagnosis involves physical examination, laboratory studies, imaging studies, and histopathological studies. The main diagnostic test to assess the condition is a skin biopsy. The skin biopsy reveals the characteristic pathological features of the condition, like increased mucin deposition, increased collagen, and numerous irregularly shaped fibroblasts. Laboratory studies include serum and urine protein electrophoresis for paraproteins and thyroid function tests. Serum analysis can indicate hyperproteinemia (presence of IgG monoclonal gammopathy). The thyroid function tests are usually normal. If the patient has neurologic, cardiovascular, and gastrointestinal symptoms, they should be evaluated accordingly. Imaging studies like X-rays or ultrasonography are done to assess systemic involvement.
What Are the Differential Diagnoses of Scleromyxedema?
The differential diagnoses of scleromyxedema include;
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Dermatological manifestations of leprosy.
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Scleredema.
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Acute complications of sarcoidosis.
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Xanthomas (fats build up under the skin).
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Morphea (a skin condition characterized by discolored patches under the skin).
How to Treat Scleromyxedema?
There is no standard treatment devised as its etiology is unclear, and the condition is rare. It is often a complex condition to treat. It may require aggressive treatment and long-term maintenance in severe cases. As this condition has systemic involvement, the patient may also need help from other specialties.
Many treatment modalities have been used for this condition, namely;
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Administration of Melphalan.
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Systemic corticosteroids.
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Cyclophosphamide.
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Psoralen combined with ultraviolet light A (PUVA).
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Retinoids.
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Surgical intervention.
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Electron beams.
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High-dose Dexamethasone.
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Carbon dioxide laser excision.
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Intravenous immunoglobulins with or without Thalidomide.
According to studies, intravenous immunoglobulins (IVIG) are most successful, with relatively minor side effects in treating scleromyxedema. It is often given with Thalidomide or Lenalidomide. Recent studies show that intravenous immunoglobulins and Lenalidomide helped significantly improve the condition with no recurrence for two years. Melphalan and Dexamethasone treatment is also successful. But Melphalan may lead to malignancies that can cause the patient's death. Oral Isotretinoin and topical corticosteroids are also useful in reducing the hardening of the skin.
Plasmapheresis refers to procedures in which blood plasma is separated from blood, treated, and returned to the body. It is effective but only for the short term. There can be a relapse of the condition with this treatment. So, the most effective treatment includes the use of IVIG (intravenous immune globulin). However, it is pretty challenging from the financial aspect. If a patient cannot receive IVIG, Melphalan or Dexamethasone is usually recommended.
Conclusion:
Scleromyxedema has a poor prognosis, especially if conditions like myeloma accompany it. There are also chances that this condition can have a long-term effect that can cause disabilities. This may affect the affected individual psychologically. In such cases, patients can take counseling or psychiatric therapy to reduce unnecessary anxieties regarding the condition so that the systemic treatment can be more effective.
