Perrault syndrome

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Perrault syndrome is a rare condition that causes different patterns of signs and symptoms in affected males and females. A key feature of this condition is hearing loss, which occurs in both males and females. Affected females also have abnormalities of the ovaries. Neurological problems occur in some affected males and females.

In Perrault syndrome, the problems with hearing are caused by changes in the inner ear, which is known as sensorineural hearing loss. The impairment usually affects both ears and can be present at birth or begin in early childhood. Unless hearing is completely impaired at birth, the hearing problems worsen over time.

Females with Perrault syndrome have abnormal or missing ovaries (ovarian dysgenesis), although their external genitalia are normal. Severely affected girls do not begin menstruation by age 16 (primary amenorrhea), and most never have a menstrual period. Less severely affected women have an early loss of ovarian function (primary ovarian insufficiency); their menstrual periods begin in adolescence, but they become less frequent and eventually stop before age 40. Women with Perrault syndrome may have difficulty conceiving or be unable to have biological children (infertile).

Neurological problems in individuals with Perrault syndrome can include intellectual disability, difficulty with balance and coordinating movements (ataxia), and loss of sensation and weakness in the limbs (peripheral neuropathy). However, not everyone with this condition has neurological problems.

Causes and biological mechanisms

From: MedlinePlus Genetics, National Library of Medicine

Perrault syndrome has several genetic causes. TWNK, CLPP, HARS2, LARS2, or HSD17B4 gene mutations have been found in a small number of affected individuals. The proteins produced from several of these genes, including TWNK, CLPP, HARS2, and LARS2, function in cell structures called mitochondria, which convert the energy from food into a form that cells can use. Although the effect of these gene mutations on mitochondrial function is unknown, researchers speculate that disruption of mitochondrial energy production could underlie the signs and symptoms of Perrault syndrome.

The protein produced from the HSD17B4 gene is active in cell structures called peroxisomes, which contain a variety of enzymes that break down many different substances in cells. It is not known how mutations in this gene affect peroxisome function or lead to hearing loss in affected males and females and ovarian abnormalities in females with Perrault syndrome.

It is likely that other genes that have not been identified are also involved in this condition.

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 do not show signs and symptoms of the condition.

How common is it?

From: MedlinePlus Genetics, National Library of Medicine

Perrault syndrome is a rare disorder; fewer than 100 affected individuals have been described in the medical literature. It is likely that the condition is underdiagnosed, because males without an affected sister will likely be misdiagnosed as having isolated (nonsyndromic) hearing loss rather than Perrault syndrome.

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.

Increased circulating gonadotropin level · Very frequent (99-80%)

Overproduction of gonadotropins (FSH, LH) by the anterior pituitary gland.

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.

Hypoplasia of the uterus · Frequent (79-30%)

Underdevelopment of the uterus.

Premature ovarian insufficiency · Frequent (79-30%)

Amenorrhea due to loss of ovarian function before the age of 40. Primary ovarian insuficiency (POI) is a state of female hypergonadotropic hypogonadism. It can manifest as primary amenorrhea with onset before menarche or secondary amenorrhea.

Streak ovary · Frequent (79-30%)

A developmental disorder characterized by the progressive loss of primordial germ cells in the developing ovaries of an embryo, leading to hypoplastic ovaries composed of wavy connective tissue with occasional clumps of granulosa cells, and frequently mesonephric or hilar cells.

Primary amenorrhea · Frequent (79-30%)

Abnormal pyramidal sign · Occasional (29-5%)

Functional neurological abnormalities related to dysfunction of the pyramidal tract.

Ataxia · Occasional (29-5%)

Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly).

Other findings in the same source

From: Orphanet

Additional reported features include Azoospermia (Occasional (29-5%)); Bicornuate uterus (Occasional (29-5%)); Cleft palate (Occasional (29-5%)); Disproportionate tall stature (Occasional (29-5%)); Global developmental delay (Occasional (29-5%)); High palate (Occasional (29-5%)); Obesity (Occasional (29-5%)); Oligomenorrhea (Occasional (29-5%)); Peripheral axonal neuropathy (Occasional (29-5%)); Specific learning disability (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

Which doctor should you see?

The suggested department for discussing Perrault 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 Perrault 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.