Hallermann-Streiff syndrome

What it is

From: Orphanet

Hallermann-Streiff syndrome is a rare genetic syndrome characterized mainly by head and facial abnormalities such as bird-like facies (with beak-shaped nose and retrognathia), hypoplastic mandible, brachycephaly with frontal bossing, dental abnormalities (e.g. absence of teeth, natal teeth, supernumerary teeth, severe agenesis of permanent teeth, enamel hypoplasia) hypotrichosis, various ophthalmic disorders (e.g. congenital cataracts, bilateral microphthalmia, ptosis, nystagmus) and atrophy of skin (especially around the center of face and nose) as well as telangiectasia and proportionate short stature. Intellectual disability is reported in some cases.

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 dentition · Very frequent (99-80%)

Any abnormality of the teeth.

Alopecia · Very frequent (99-80%)

A noncongenital process of hair loss, which may progress to partial or complete baldness.

Brachycephaly · Very frequent (99-80%)

An abnormality of skull shape characterized by a decreased anterior-posterior diameter. That is, a cephalic index greater than 81%. Alternatively, an apparently shortened anteroposterior dimension (length) of the head compared to width.

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

Nasal ridge curving anteriorly to an imaginary line that connects the nasal root and tip. The nose appears often also prominent, and the columella low.

Dermal atrophy · Very frequent (99-80%)

Partial or complete wasting (atrophy) of the skin.

Developmental cataract · Very frequent (99-80%)

A cataract that occurs congenitally as the result of a developmental defect, in contrast to the majority of cataracts that occur in adulthood as the result of degenerative changes of the lens.

Frontal bossing · Very frequent (99-80%)

Bilateral bulging of the lateral frontal bone prominences with relative sparing of the midline.

Microphthalmia · Very frequent (99-80%)

A developmental anomaly characterized by abnormal smallness of one or both eyes.

Proportionate short stature · Very frequent (99-80%)

A kind of short stature in which different regions of the body are shortened to a comparable extent.

Reduced bone mineral density · Very frequent (99-80%)

A reduction of bone mineral density, that is, of the amount of matter per cubic centimeter of bones.

Rib exostoses · Very frequent (99-80%)

Multiple circumscribed bony excrescences located in the ribs.

Short ribs · Very frequent (99-80%)

Reduced rib length.

Sparse body hair · Very frequent (99-80%)

Sparseness of the body hair.

Sparse hair · Very frequent (99-80%)

Reduced density of hairs.

Other findings in the same source

From: Orphanet

Additional reported features include Abnormality of hair texture (Frequent (79-30%)); Abnormality of the fontanelles or cranial sutures (Frequent (79-30%)); Abnormality of the tongue (Frequent (79-30%)); Glossoptosis (Frequent (79-30%)); High, narrow palate (Frequent (79-30%)); Malar flattening (Frequent (79-30%)); Micrognathia (Frequent (79-30%)); Narrow mouth (Frequent (79-30%)); Natal tooth (Frequent (79-30%)); Recurrent fractures (Frequent (79-30%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Antenatal; Infancy; Neonatal

Inheritance in the source

From: Orphanet

Not applicable; Unknown

Frequency and the population described

From: Orphanet

Reported case(s): 150.0; Worldwide. This is a published case count, not prevalence. Point prevalence: Unknown; Worldwide; Class only. Prevalence at birth: 1-9 / 100 000; Japan; Value and class.

Which doctor should you see?

The suggested department for discussing Hallermann-Streiff 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 Hallermann-Streiff 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.