What are the other Names for this Condition? (Also known as/Synonyms)

• Lichen Myxoedematosus
• LM (Lichen Myxedematosus)
• Papular Mucinosis

What is Lichen Myxedematosus? (Definition/Background Information)

• Lichen Myxedematosus (LM) is a rare and chronic skin disorder wherein there is abnormal deposition of mucin (a group of proteins secreted by mucus membranes) in the skin. The disorder is also known as Papular Mucinosis
• The classification of Lichen Myxedematosus includes the localized, generalized, and atypical forms. The generalized form is more severe than the localized forms. The atypical form may present a combination of features from both the localized and generalized form
• Lichen Myxedematosus presents tiny skin-colored papules all over the body. Apart from the skin, some subtypes may involve several body systems, such as the bones and muscles, central nervous system, digestive system, and respiratory system, resulting in severe complications
• The condition is diagnosed by a skin biopsy. Following the diagnosis of Lichen Myxedematosus, the treatment is undertaken for skin symptoms and systemic symptoms, if present. The treatment may include light therapy, use of topical creams, dermabrasion, administration of corticosteroids, and intravenous immunoglobulin
• The outcome of Lichen Myxedematosus depends upon the severity of the condition. Generally, the prognosis of the localized forms is much better than that of the generalized and atypical forms, since it is known to be self-limited

Lichen Myxedematosus is classified into several forms that include:

• Generalized form: Scleromyxedema
• Localized forms:
  • Discrete papular Lichen Myxedematosus
  • Acral persistent Papular Mucinosis
  • Self-healing Papular Mucinosis (juvenile and adult variants)
  • Cutaneous mucinosis of infancy
  • Nodular Lichen Myxedematosus
• Atypical forms:
  • Scleromyxedema without monoclonal gammopathy
  • Localized Lichen Myxedematosus with monoclonal gammopathy and/or systemic symptoms
  • Localized Lichen Myxedematosus with mixed features of different subtypes
  • Not otherwise specified

Who gets Lichen Myxedematosus? (Age and Sex Distribution)

• Lichen Myxedematosus is an uncommon skin condition that may be diagnosed in adults and children, depending on the specific subtype of the condition observed
• Both males and females are affected
• All racial and ethnic groups are affected and no predilection is observed

What are the Risk Factors for Lichen Myxedematosus? (Predisposing Factors)

Currently, there are no specific risk factors identified for Lichen Myxedematosus. However, the following may be noted:

• Occasionally, a few cases of the generalized form of Lichen Myxedematosus have been associated with blood and bone marrow conditions, such as leukemia, lymphoma, and multiple myeloma
• Some localized forms of Lichen Myxedematosus are associated with exposure to toxic substances, such as certain oils, and contaminated L-tryptophan (an amino acid)

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Lichen Myxedematosus? (Etiology)

• The exact cause of Lichen Myxedematosus formation is generally unknown. It may be due to an abnormal immune function
• Scleromyxedema (the generalized form of Lichen Myxedematosus) is known to be associated with monoclonal gammopathy, in a majority of cases. Monoclonal gammopathy is a disorder wherein there is an increase of immunoglobulins, a type of protein that normally helps with immunity. In this situation, a very large clone of non-functional antibodies flood the system

Lichen Myxedematosus is a non-contagious condition, and it cannot spread from one individual to another. Hence, one cannot get it through direct contact, or by being in close proximity to an individual with the condition.

What are the Signs and Symptoms of Lichen Myxedematosus?

The signs and symptoms of Lichen Myxedematosus depend on the specific subtype of the condition. In general, the signs and symptoms may include:

• Presence of numerous, small round papules on skin that are firm, flesh-colored, and waxy in appearance
• A papule is an area of abnormal skin tissue that is less than 1 centimeter around. Usually a papule has distinct borders, and it can appear in a variety of shapes
• The papules can be present anywhere on the body; on the head and neck region, limbs (arms and legs), and chest and back
• Thickening of skin may be observed

Besides the skin, the condition may involve several parts of the body such as the upper airways, pharynx, eyes, voice box, gastrointestinal tract, and heart, leading to severe symptoms. The localized forms/subtypes do not present any systemic involvement.

Nevertheless, systemic symptoms may or may not be observed and is dependent upon the specific subtype of Lichen Myxedematosus (i.e., whether it is a generalized form or atypical form).

How is Lichen Myxedematosus Diagnosed?

Lichen Myxedematosus may be diagnosed through the following tools:

• Complete physical examination with evaluation of medical history
• Dermoscopy: It is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• Complete blood count
• Blood and urine tests; protein electrophoresis
• Quantitative testing of immunoglobulins, and for their diversity (polyclonal or monoclonal)
• Thyroid function test
• Antinuclear antibody (ANA) blood test
• Tests and procedures to detect an underlying condition, if any present
• Skin biopsy: A skin biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Lichen Myxedematosus?

Several body systems may be affected by Lichen Myxedematosus based upon the characteristic subtype noted. The localized forms and some of the atypical forms do not present any systemic symptoms, unlike the generalized form.

Some of the complications observed may include:

• Scratching or itching of the lesions may lead to bleeding and ulceration. This can cause secondary bacterial or fungal infections to develop
• Severe emotional stress due to cosmetic concerns
• Loss of vision or impaired vision
• Abnormal lung function causing breathing difficulties
• Swallowing difficulties due to lack of esophageal muscle contraction
• Hoarse voice
• Arthritis involving several body joints (polyarthritis)
• Carpal tunnel syndrome
• Muscle weaknesses due to myopathy
• Central nervous system involvement causing brain damage
• Kidney failure
• Heart abnormalities

How is Lichen Myxedematosus Treated?

Currently, there is no specific treatment for Lichen Myxedematosus. It is also generally difficult to treat this progressive condition. In the localized forms, a spontaneous resolution of the condition may be noted. Otherwise, long-term and often aggressive therapy is needed to address the severe symptoms and multi-system complications that arise.

The following treatment measures may be recommended in treating Lichen Myxedematosus depending on the combination of underlying signs and symptoms noted.

• Administration of intravenous immunoglobulin (IVIG)
• Plasmapheresis; the removal or exchange of certain components of blood
• Use of systemic steroids
• Autologous bone marrow transplantation, for severe disease
• Administration of chemotherapy medications
• Symptomatic and supportive therapy

In case of systemic symptoms that affect the whole body:

• Administration of intravenous immunoglobulin (IVIG)
• Plasmapheresis; the removal of exchange of certain components of blood
• Use of systemic steroids
• Autologous bone marrow transplantation, for severe disease
• Administration of chemotherapy medications
• Symptomatic and supportive therapy

How can Lichen Myxedematosus be Prevented?

Current medical research has not established a method of preventing the development of Lichen Myxedematosus.

What is the Prognosis of Lichen Myxedematosus? (Outcomes/Resolutions)

• The prognosis of Lichen Myxedematosus is dependent upon the specific subtype and the severity of the signs and symptoms and associated complications, if any present
• Individuals with mild conditions have better prognosis than those with severe symptoms and complications. Thus, individuals with skin-alone symptoms (localized type) have better prognoses than those with symptoms that involve entire body systems (generalized type and some atypical types)
• Typically, the prognosis may be only assessed on a case-by-case basis

Additional and Relevant Useful Information for Lichen Myxedematosus:

• It is advised to not pick or scratch the lesions
• Cleaning the skin too hard with strong chemicals or soaps may aggravate the skin condition. Care must be taken avoid strong soaps and chemicals that could potentially worsen the condition