Autosomal recessive chorioretinopathy-microcephaly syndrome

What it is

From: Orphanet

A rare neuro-opthalmological disease characterized by severe microcephaly of prenatal onset (with diminutive anterior fontanelle and sutural ridging), growth retardation, global developmental delay and intellectual disability (ranging from mild to profound), dysmorphic features (sloping forehead, micro/retrognathia, prominent ears) and visual impairments (including microphthalmia to anophtalmia, generalized retinopathy or multiple punched-out retinal lesions, retinal folds with retinal detachment, optic nerve hypoplasia, strabismus, nystagmus). Brain MRI may show reduced cortical size, cerebral hemispheres, corpus callosum, pachygyria, symplified gyral folding or normal pattern. Other associated features include epilepsy and neurological deficits.

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 retinal pigmentation · Very frequent (99-80%)

Any deviation from the normal pigmentation of the retina.

Microcephaly · Very frequent (99-80%)

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

Abnormal eyelash morphology · Frequent (79-30%)

An abnormality of the eyelashes.

Abnormality of neuronal migration · Frequent (79-30%)

An abnormality resulting from an anomaly of neuronal migration, i.e., of the process by which neurons travel from their origin to their final position in the brain.

Anteverted nares · Frequent (79-30%)

Anteriorly-facing nostrils viewed with the head in the Frankfurt horizontal and the eyes of the observer level with the eyes of the subject. This gives the appearance of an upturned nose (upturned nasal tip).

Biparietal narrowing · Frequent (79-30%)

A narrowing of the biparietal diameter (i.e., of the transverse distance between the protuberances of the two parietal bones of the skull).

Cerebral cortical atrophy · Frequent (79-30%)

Atrophy of the cortex of the cerebrum.

Hypertonia · Frequent (79-30%)

A condition in which there is increased muscle tone so that arms or legs, for example, are stiff and difficult to move.

Intellectual disability · Frequent (79-30%)

The term intellectual disability or intellectual developmental disorder is used to describe significantly sub-average intellectual and adaptive functioning based on clinical assessment and as measured by individually administered, appropriately normed, standardized and validated tests of intellectual functioning and adaptive behavior, with onset during the developmental period from infancy through adolescence.

Intrauterine growth retardation · Frequent (79-30%)

An abnormal restriction of fetal growth with fetal weight below the tenth percentile for gestational age.

Nystagmus · Frequent (79-30%)

Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.

Optic atrophy · Frequent (79-30%)

Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy.

Pointed chin · Frequent (79-30%)

A marked tapering of the lower face to the chin.

Protruding ear · Frequent (79-30%)

Angle formed by the plane of the ear and the mastoid bone greater than the 97th centile for age (objective); or, outer edge of the helix more than 2 cm from the mastoid at the point of maximum distance (objective).

Other findings in the same source

From: Orphanet

Additional reported features include Scoliosis (Frequent (79-30%)); Seizure (Frequent (79-30%)); Short stature (Frequent (79-30%)); Sloping forehead (Frequent (79-30%)); Strabismus (Frequent (79-30%)); Visual impairment (Frequent (79-30%)); Wide nasal bridge (Frequent (79-30%)); Aplasia/Hypoplasia of the cerebellum (Frequent (79-30%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Neonatal

Inheritance in the source

From: Orphanet

Autosomal recessive

Understanding the inheritance label

From: MedlinePlus Genetics

An autosomal recessive pattern usually involves disease-causing changes in both copies of a gene. Parents may each carry one altered copy without having the condition themselves. A genetic counsellor can explain carrier testing and reproductive implications using the actual laboratory findings, rather than the condition name alone.

Which doctor should you see?

The suggested department for discussing Autosomal recessive chorioretinopathy-microcephaly syndrome is Ophthalmology, with a ophthalmologist as the relevant type of clinician. Ophthalmologist; 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 part of the eye or visual pathway is affected?
• What change in vision requires immediate contact with the eye service?
• What are the aims and alternatives of any proposed eye treatment?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Autosomal recessive chorioretinopathy-microcephaly 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.