Lipoid proteinosis

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Lipoid proteinosis is a condition that results from the formation of numerous small clumps (deposits) of proteins and other molecules in various tissues throughout the body. These tiny clumps appear in the skin, upper respiratory tract, the moist tissues that line body openings such as the eyelids and the inside of the mouth (mucous membranes), and other areas.

The first symptom of this condition is usually a hoarse voice, which is due to deposits in the vocal cords. In infancy the hoarseness is expressed as a weak cry. The voice abnormalities persist throughout life and can ultimately cause difficulty speaking or complete loss of speech. Involvement of the throat, tonsils, and lips can result in breathing problems and upper respiratory tract infections. Deposits in the tongue can result in a thick and shortened tongue. They can also thicken the band of tissue that connects the tongue to the bottom of the mouth (frenulum), making it difficult to extend the tongue. The tongue may also have a smooth appearance due to damage to the taste buds.

A characteristic feature of lipoid proteinosis is the presence of multiple tiny, bead-like bumps lining the upper and lower eyelids along the lash line. These bumps are known as moniliform blepharosis. They may cause eyeball irritation or itching but generally do not impair vision.

The skin and mucous membranes are often fragile in children with lipoid proteinosis, leading to bleeding and scabbing following minor trauma. These problems often first appear in infancy in the mouth and on the face and limbs. Over time, these scabs form blisters and scars. Deposits accumulate in the skin, which causes the skin to become thickened and yellowish in color. Skin damage appears more frequently on areas that experience friction, such as the hands, elbows, knees, buttocks, and armpits. Some people with this condition have hair loss (alopecia) affecting their scalp, eyelashes, and eyebrows.

Neurologic features are also common in people with lipoid proteinosis. Affected individuals may have recurrent seizures (epilepsy) or behavioral and neurological problems, which can include headaches, aggressive behaviors, paranoia, hallucinations, short-term memory loss, and absence of fear. These features are thought to be associated with the presence of deposits and an accumulation of calcium (calcification) in areas of the brain called the temporal lobes. The temporal lobes help process hearing, speech, memory, and emotion. The brain abnormalities and neurological features do not always occur together, so the cause of the neurological features is still unclear.

Deposits can be found in some internal organs, including the stomach, a section of the small intestine called the duodenum, and the colon. The deposits in these tissues often do not cause any symptoms and may disappear over time.

Causes and biological mechanisms

From: MedlinePlus Genetics, National Library of Medicine

Lipoid proteinosis is caused by mutations in the ECM1 gene. This gene provides instructions for making a protein that is found in most tissues within the extracellular matrix, which is an intricate lattice that forms in the space between cells and provides structural support. The ECM1 protein can attach (bind) to numerous structural proteins to provide strength to tissues. It is also involved in the growth and maturation (differentiation) of cells, including skin cells called keratinocytes. The ECM1 protein may also regulate the formation of blood vessels (angiogenesis).

ECM1 gene mutations that cause lipoid proteinosis result in the production of a nonfunctional protein or no protein at all. A lack of functional ECM1 protein reduces binding between ECM1 and other proteins, leading to an unstable extracellular matrix. Without adequate support from the extracellular matrix, cells in the skin and other tissues are weakened. However, the cause of the deposits in skin and other tissues is not clear. The unstable extracellular matrix may cause neighboring cells to overproduce proteins and other materials. It is possible that, as these excess substances accumulate in tissues, they create the deposits characteristic of lipoid proteinosis.

Inheritance and family implications

From: MedlinePlus Genetics, National Library of Medicine

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.

How common is it?

From: MedlinePlus Genetics, National Library of Medicine

Lipoid proteinosis is thought to be a rare condition; fewer than 500 cases have been described in the scientific literature. This condition occurs more frequently in certain areas of the world, including Turkey, Iran, and the Northern Cape province of South Africa.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Abnormal blistering of the skin · Very frequent (99-80%)

The presence of one or more bullae on the skin, defined as fluid-filled blisters more than 5 mm in diameter with thin walls.

Abnormal oral mucosa morphology · Very frequent (99-80%)

Abnormality of the oral mucosa.

Abnormality of the gingiva · Very frequent (99-80%)

Any abnormality of the gingiva (also known as gums).

Acne · Very frequent (99-80%)

A skin condition in which there is an increase in sebum secretion by the pilosebaceous apparatus associated with open comedones (blackheads), closed comedones (whiteheads), and pustular nodules (papules, pustules, and cysts).

Hoarse voice · Very frequent (99-80%)

Hoarseness refers to a change in the pitch or quality of the voice, with the voice sounding weak, very breathy, scratchy, or husky.

Papule · Very frequent (99-80%)

A circumscribed, solid elevation of skin with no visible fluid, varying in size from a pinhead to less than 10mm in diameter at the widest point.

Pustule · Very frequent (99-80%)

A small elevation of the skin containing cloudy or purulent material usually consisting of necrotic inflammatory cells.

Scarring · Very frequent (99-80%)

A scar refers to a lesion in which wound, burn, or sore has not healed completely and fibrous connective tissue has developed.

Other findings in the same source

From: Orphanet

Additional reported features include Subcutaneous nodule (Very frequent (99-80%)); Thick lower lip vermilion (Very frequent (99-80%)); Thickened skin (Very frequent (99-80%)); Tongue nodules (Very frequent (99-80%)); Dysphagia (Frequent (79-30%)); Dystonia (Frequent (79-30%)); High palate (Frequent (79-30%)); Hyperkeratosis (Frequent (79-30%)); Microglossia (Frequent (79-30%)); Recurrent respiratory infections (Frequent (79-30%)). This is a selected summary, not a complete description of the condition.

Which doctor should you see?

The suggested department for discussing Lipoid proteinosis is Dermatology, with a dermatologist as the relevant type of clinician. Dermatologist; paediatric services for children as appropriate.

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.

• Which features of the skin, hair or nails distinguish the possibilities?
• Would photographs over time help document the changes?
• What should be expected from treatment, and how will irritation or other adverse effects be managed?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Lipoid proteinosis. 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.