Nevus comedonicus syndrome

What it is

From: Orphanet

A rare, syndromic nevus characterized by the association of typically unilateral, closely arranged, linear, slightly elevated, multiple, nevus comedonicus lesions located usually on the face, neck, trunk or limbs (with or without a central, dark, firm, hyperkeratotic plug and secondary acneiform lesions) with extracutaneous ocular, skeletal, and/or central nervous system abnormalities, such as ipsilateral cataract, corneal erosion, poly-/syndactyly, absent fifth finger, scoliosis, vertebral defects, corpus callosum agenesis, seizures, interhemispheric cyst, intellectual deficiency, and/or developmental delay.

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.

Comedo · Very frequent (99-80%)

A clogged cutaneous sebaceous follicle, which is a cutaneous gland that secretes sebum (usually into a hair follicle).

Hamartoma · Very frequent (99-80%)

A disordered proliferation of mature tissues that is native to the site of origin, e.g., exostoses, nevi and soft tissue hamartomas. Although most hamartomas are benign, some histologic subtypes, e.g., neuromuscular hamartoma, may proliferate aggressively such as mesenchymal cystic hamartoma, Sclerosing epithelial hamartoma, Sclerosing metanephric hamartoma.

Abnormal foot morphology · Occasional (29-5%)

An abnormality of the skeleton of foot.

Abnormal vertebral morphology · Occasional (29-5%)

An abnormality of one or more of the vertebrae.

Abnormality of the hair · Occasional (29-5%)

An abnormality of the hair.

Cataract · Occasional (29-5%)

A cataract is an opacity or clouding that develops in the crystalline lens of the eye or in its capsule.

Finger syndactyly · Occasional (29-5%)

Webbing or fusion of the fingers, involving soft parts only or including bone structure. Bony fusions are referred to as "bony" Syndactyly if the fusion occurs in a radio-ulnar axis. Fusions of bones of the fingers in a proximo-distal axis are referred to as "Symphalangism".

Ichthyosis · Occasional (29-5%)

An abnormality of the skin characterized the presence of excessive amounts of dry surface scales on the skin resulting from an abnormality of keratinization.

Microcephaly · Occasional (29-5%)

Head circumference below 2 standard deviations below the mean for age and gender.

Nevus flammeus · Occasional (29-5%)

A congenital vascular malformation consisting of superficial and deep dilated capillaries in the skin which produce a reddish to purplish discolouration of the skin.

Preaxial polydactyly · Occasional (29-5%)

A form of polydactyly in which the extra digit or digits are localized on the side of the thumb or great toe.

Scoliosis · Occasional (29-5%)

The presence of an abnormal lateral curvature of the spine.

Seizure · Occasional (29-5%)

A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.

Spina bifida · Occasional (29-5%)

Incomplete closure of the embryonic neural tube, whereby some vertebral arches remain unfused and open. The mildest form is spina bifida occulta, followed by meningocele and meningomyelocele.

Other findings in the same source

From: Orphanet

Additional reported features include Spina bifida occulta (Occasional (29-5%)); Toe syndactyly (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Childhood; Infancy; Neonatal

Inheritance in the source

From: Orphanet

Not applicable

Frequency and the population described

From: Orphanet

Point prevalence: Unknown; Worldwide; Class only.

Which doctor should you see?

The suggested department for discussing Nevus comedonicus syndrome 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 Nevus comedonicus syndrome. 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.