Craniofacial-deafness-hand syndrome

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Craniofacial-deafness-hand syndrome is characterized by distinctive facial features, profound hearing loss, and hand abnormalities.

The distinctive facial features of people with craniofacial-deafness-hand syndrome result from a variety of developmental abnormalities involving the skull (cranium) and face. Affected individuals often have underdeveloped or absent nasal bones resulting in a small nose, thin nostrils, and a flattened mid-face with a flat nasal bridge. Individuals with this condition typically also have widely spaced eyes (ocular hypertelorism), narrowed openings of the eyes (narrowed palpebral fissures), a small upper jaw (hypoplastic maxilla), and a small mouth with pursed lips.

People with this condition also have profound hearing loss that is caused by abnormalities in the inner ear (sensorineural deafness). Hearing loss in these individuals is present from birth.

In affected individuals, a common abnormality of the muscles in the hand is a malformation in which all of the fingers are angled outward toward the fifth finger (ulnar deviation). People with craniofacial-deafness-hand syndrome may also have permanently bent third, fourth, and fifth fingers (camptodactyly), which can limit finger movement and lead to joint deformities called contractures. Contractures in the wrist can further impair hand movements.

Causes and biological mechanisms

From: MedlinePlus Genetics, National Library of Medicine

Craniofacial-deafness-hand syndrome is caused by mutations in the PAX3 gene. The PAX3 gene plays a critical role in the formation of tissues and organs during embryonic development. To perform this function, the gene provides instructions for making a protein that attaches (binds) to specific areas of DNA to help control the activity of particular genes. During embryonic development, the PAX3 gene is active in cells called neural crest cells. These cells migrate from the developing spinal cord to specific regions in the embryo. The protein produced from the PAX3 gene directs the activity of other genes that signal neural crest cells to form specialized tissues or cell types. These include some nerve tissues, bones in the face and skull (craniofacial bones), and muscle tissue.

At least one PAX3 gene mutation has been identified in individuals with craniofacial-deafness-hand syndrome. This mutation appears to affect the ability of the PAX3 protein to bind to DNA. As a result, the PAX3 protein cannot control the activity of other genes and cannot regulate the differentiation of neural crest cells. A lack of specialization of neural crest cells leads to the impaired growth of craniofacial bones, nerve tissue, and muscles seen in craniofacial-deafness-hand syndrome.

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.

How common is it?

From: MedlinePlus Genetics, National Library of Medicine

Craniofacial-deafness-hand syndrome is an extremely rare condition. Only a few cases have been reported in the scientific literature.

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.

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

Abnormality of the wrist, the structure connecting the hand and the forearm.

Aplasia/Hypoplasia involving the nose · Very frequent (99-80%)

Underdevelopment or absence of the nose or parts thereof.

Blepharophimosis · Very frequent (99-80%)

A fixed reduction in the vertical distance between the upper and lower eyelids with short palpebral fissures.

Depressed nasal bridge · Very frequent (99-80%)

Posterior positioning of the nasal root in relation to the overall facial profile for age.

Depressed nasal ridge · Very frequent (99-80%)

Lack of prominence of the nose resulting from a posteriorly-placed nasal ridge.

Downslanted palpebral fissures · Very frequent (99-80%)

The palpebral fissure inclination is more than two standard deviations below the mean.

Flat face · Very frequent (99-80%)

Absence of concavity or convexity of the face when viewed in profile.

Hypertelorism · Very frequent (99-80%)

Interpupillary distance more than 2 SD above the mean (alternatively, the appearance of an increased interpupillary distance or widely spaced eyes).

Hypoplasia of the maxilla · Very frequent (99-80%)

Abnormally small dimension of the Maxilla. Usually creating a malocclusion or malalignment between the upper and lower teeth or resulting in a deficient amount of projection of the base of the nose and lower midface region.

Lacrimal duct atresia · Very frequent (99-80%)

A developmental disorder of the lacrimal drainage system that most often affects the lacrimal ostium and resulting in non-opening of the nasolacrimal duct. It usually results from a non-canalization of the nasolacrimal duct.

Narrow face · Very frequent (99-80%)

Bizygomatic (upper face) and bigonial (lower face) width are both more than 2 standard deviations below the mean (objective); or, an apparent reduction in the width of the upper and lower face (subjective).

Narrow mouth · Very frequent (99-80%)

Distance between the commissures of the mouth more than 2 SD below the mean. Alternatively, an apparently decreased width of the oral aperture (subjective).

Sensorineural hearing impairment · Very frequent (99-80%)

A type of hearing impairment in one or both ears related to an abnormal functionality of the cochlear nerve.

Short nose · Very frequent (99-80%)

Distance from nasion to subnasale more than two standard deviations below the mean, or alternatively, an apparently decreased length from the nasal root to the nasal tip.

Other findings in the same source

From: Orphanet

Additional reported features include Ulnar deviation of finger (Very frequent (99-80%)); Ulnar deviation of the wrist (Very frequent (99-80%)); Camptodactyly of finger (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 Craniofacial-deafness-hand syndrome is Clinical Genetics, with a clinical geneticist as the relevant type of clinician. Paediatrician (children) or physician (adults), with clinical geneticist referral.

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.

• Does the exact genetic or chromosome finding explain the observed features?
• Would a genetic counsellor help the family understand the result?
• Which organ-specific assessments are appropriate for this particular diagnosis?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Craniofacial-deafness-hand 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.