Hereditary fibrosing poikiloderma with tendon contractures, myopathy, and pulmonary fibrosis

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Hereditary fibrosing poikiloderma with tendon contractures, myopathy, and pulmonary fibrosis (abbreviated POIKTMP), is a disorder that affects many parts of the body, particularly the skin, muscles, lungs, and pancreas. Signs and symptoms vary among affected individuals.

People with POIKTMP have patchy changes in skin coloring and small clusters of blood vessels just under the skin (telangiectases), a combination known as poikiloderma. These skin changes begin in infancy and occur primarily on the face. They can also have red, scaly skin patches and mild swelling (lymphedema) of the arms and legs; thickened skin on the palms of the hands and soles of the feet (palmoplantar keratoderma); and abnormal hardening (sclerosis) of tissues in the fingers and toes. People with this disorder usually have sparse scalp hair, and their eyelashes and eyebrows can also be sparse or absent. Affected individuals have a decreased ability to sweat (hypohidrosis), which impairs their ability to tolerate heat.

Reduced movement of joints (contractures) caused by shortening of the connective tissues that attach muscles to bone (tendons) usually develops during childhood in people with POIKTMP. These contractures often affect the calf, resulting in turning in (valgus deformity) of the feet. Contractures can also affect the elbows and wrists. In addition, people with POIKTMP usually develop muscle weakness (myopathy) in the arms and legs, and medical imaging shows abnormal fatty tissue in the muscles.

Adults with POIKTMP can develop a condition called pulmonary fibrosis, in which scar tissue forms in the lungs. Pulmonary fibrosis eventually causes difficulty breathing and can be life-threatening within a few years after symptoms begin.

In addition to the skin, muscle, and lung problems that give this condition its name, people with POIKTMP can also have a shortage (deficiency) of enzymes produced by the pancreas to aid in the digestion of fats. This deficiency can lead to diarrhea and poor absorption of fats and fat-soluble vitamins. Liver problems, short stature, and delayed puberty can also occur in affected individuals. Intellectual development is not affected by this disorder.

Causes and biological mechanisms

From: MedlinePlus Genetics, National Library of Medicine

POIKTMP is caused by mutations in the FAM111B gene. This gene provides instructions for making a protein whose function is not well understood. The FAM111B protein, which is found in many parts of the body, contains a functional region called a peptidase domain. Similar proteins containing such a domain are able to break down other proteins. However, the types of proteins the FAM111B protein interacts with and the roles it plays in the body are unknown.

The FAM111B gene mutations that cause POIKTMP result in production of an abnormal FAM111B protein from one copy of the gene in each cell. Because most of the FAM111B mutations identified in people with POIKTMP result in changes in the peptidase domain, researchers think that the mutations alter the protein's function, and that these changes in FAM111B function underlie the varied signs and symptoms of POIKTMP.

Inheritance and family implications

From: MedlinePlus Genetics, National Library of Medicine

This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.

In about half of cases, an affected person inherits the mutation from one affected parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family.

How common is it?

From: MedlinePlus Genetics, National Library of Medicine

The prevalence of POIKTMP is unknown. At least 25 affected individuals have been described in the medical literature. POIKTMP is thought to be underdiagnosed because affected individuals may have only one or a few features of the disorder, and health care providers may not recognize these features as part of POIKTMP.

Which doctor should you see?

The suggested department for discussing Hereditary fibrosing poikiloderma with tendon contractures, myopathy, and pulmonary fibrosis is Pulmonology, with a pulmonologist / chest physician as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• What is the likely explanation for the breathing symptoms?
• Would a breathing test or another investigation change management?
• If symptoms worsen, what written action plan should be followed?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Hereditary fibrosing poikiloderma with tendon contractures, myopathy, and pulmonary fibrosis. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.