Tangier disease

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Tangier disease is an inherited disorder characterized by significantly reduced levels of high-density lipoprotein (HDL) in the blood. HDL transports cholesterol and certain fats called phospholipids from the body's tissues to the liver, where they are removed from the blood. HDL is often referred to as "good cholesterol" because high levels of this substance reduce the chances of developing heart and blood vessel (cardiovascular) disease. Because people with Tangier disease have very low levels of HDL, they have a moderately increased risk of cardiovascular disease.

Additional signs and symptoms of Tangier disease include a slightly elevated amount of fat in the blood (mild hypertriglyceridemia); disturbances in nerve function (neuropathy); and enlarged, orange-colored tonsils. Affected individuals often develop atherosclerosis, which is an accumulation of fatty deposits and scar-like tissue in the lining of the arteries. Other features of this condition may include an enlarged spleen (splenomegaly), an enlarged liver (hepatomegaly), clouding of the outermost layer of the eye (corneal clouding), and type 2 diabetes.

ORPHANET DEFINITION A rare, genetic neurometabolic disease characterized biochemically by an almost complete absence of plasma high-density lipoproteins (HDL), and clinically by liver, spleen, lymph node and tonsil enlargement along with multifocal peripheral neuropathy, corneal, skin and nail and, occasionally, cardiovascular disease.

Inheritance

From: MedlinePlus Genetics, National Library of Medicine

Autosomal recessive

Frequency in the source

From: MedlinePlus Genetics, National Library of Medicine

Reported case(s): 185.0; Worldwide. This is a published case count, not prevalence. Point prevalence: <1 / 1 000 000; Worldwide; Class only.

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.

Hypertriglyceridemia · Very frequent (99-80%)

The concentration of triglyceride in the blood circulation is above the upper limit of normal.

Hypocholesterolemia · Very frequent (99-80%)

An decreased concentration of cholesterol in the blood.

Abdominal pain · Frequent (79-30%)

An unpleasant sensation characterized by physical discomfort (such as pricking, throbbing, or aching) and perceived to originate in the abdomen.

Accelerated atherosclerosis · Frequent (79-30%)

Atherosclerosis which occurs in a person with certain risk factors (e.g., SLE, diabetes, smoking, hypertension, hypercholesterolaemia, family history of early heart disease) at an earlier age than would occur in another person without those risk factors.

Chronic noninfectious lymphadenopathy · Frequent (79-30%)

A chronic form of lymphadenopathy that is not related to infection.

Coronary artery stenosis · Frequent (79-30%)

Abnormal narrowing of the coronary artery.

Distal muscle weakness · Frequent (79-30%)

Reduced strength of the musculature of the distal extremities.

Dry skin · Frequent (79-30%)

Skin characterized by the lack of natural or normal moisture.

Ectropion · Frequent (79-30%)

An outward turning (eversion) or rotation of the eyelid margin.

Hepatosplenomegaly · Frequent (79-30%)

Simultaneous enlargement of the liver and spleen.

Nail dystrophy · Frequent (79-30%)

Onychodystrophy (nail dystrophy) refers to nail changes apart from changes of the color (nail dyschromia) and involves partial or complete disruption of the various keratinous layers of the nail plate.

Orange discoloured tonsils · Frequent (79-30%)

A phenomenon of orange colored oral tonsils. This feature is characteristic of Tangier disease and illustrated will by Figure 1 of PMID:19470903.

Peripheral axonal neuropathy · Frequent (79-30%)

An abnormality characterized by disruption of the normal functioning of peripheral axons.

Progressive peripheral neuropathy · Frequent (79-30%)

Other findings in the same source

From: Orphanet

Additional reported features include Anemia (Occasional (29-5%)); Carotid artery stenosis (Occasional (29-5%)); Corneal opacity (Occasional (29-5%)); Facial diplegia (Occasional (29-5%)); Impaired temperature sensition (Occasional (29-5%)); Left ventricular hypertrophy (Occasional (29-5%)); Syringomyelia (Occasional (29-5%)); Thrombocytopenia (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: MedlinePlus Genetics, National Library of Medicine

Adolescent; Adult; Childhood; Infancy; Neonatal

Inheritance in the source

From: MedlinePlus Genetics, National Library of Medicine

Autosomal recessive

Frequency and the population described

From: MedlinePlus Genetics, National Library of Medicine

Reported case(s): 185.0; Worldwide. This is a published case count, not prevalence. Point prevalence: <1 / 1 000 000; Worldwide; Class only.

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 Tangier disease is Endocrinology, with a endocrinologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

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 hormone or metabolic finding is important in this case?
• How should test timing and current medicines be taken into account?
• What follow-up would show whether the care plan is working?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Tangier disease. 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.