Saving lives through education, advances in treatment and finding a cure for Barth syndrome

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How to diagnose Barth syndrome

Could you perhaps be missing a case of Barth syndrome?

There is no charge for testing UK patients as this is funded by NHS Specialised Services. Please make use of the free diagnostic test if the child in question has ANY of the following symptoms.

Cardiomyopathy
Left ventricular non-compaction
Neutropenia
Weak muscles
Family history of a male pattern of cardiomyopathy where no genetic cause can be found

Especially if any of the above symptoms also coincide with either:

Developmental delay
Feeding and/or growth problems
Fatigue

Did you know?

Barth syndrome can behave very differently between affected children
10% of affected children and adults always have normal blood neutrophil counts
The level of 3-methylglutaconic acid can sometimes be normal in urine
3-5% of all young people with DCM may have Barth syndrome as the cause of their heart failure (This percentage may be even higher in those who are in heart failure at birth or develop it within the first year of life)

Information on Testing for Barth Syndrome

Testing for Barth syndrome in the past has so far mostly been restricted to boys with dilated cardiomyopathy (DCM) AND neutropenia AND excessive amounts of 3-methylglutaconic acid in their urine. However, it is increasingly clear that the disease can behave very differently between affected children, young people and adults. As just two examples: 10% of children do NOT have low blood neutrophil counts and it is well recognised that the level of 3-methylglutaconic acid can sometimes be normal in urine.

Previously, definitive testing for Barth Syndrome relied on sequencing of the responsible TAZ gene, but this is expensive and time-consuming. A more practical approach to testing is now possible since the development of a biochemical "cardiolipin test" which can be performed very reliably on only a small volume of blood. The test result is usually available within one to two weeks and this is a more straightforward test than DNA sequencing (although gene testing would usually still be performed as further confirmation in someone with a positive cardiolipin test). When done on blood samples sent by first class post, cardiolipin testing discriminates extremely well between normal children and those with Barth Syndrome.

It has been estimated that between 3 and 5% of all young males with DCM may have Barth Syndrome as the cause of their heart failure. This percentage may be even higher in those who are in heart failure at birth or develop it within the first year of life. We therefore recommend routine cardiolipin testing in all young children with dilated cardiomyopathy (DCM). Cardiolipin testing should also be considered in male babies/boys with left ventricular noncompaction (LVNC), unexplained neutropenia (especially with poor growth, developmental delay or weak muscles and easy fatigue) and in families with a male pattern of hypertrophic cardiomyopathy (HCM) but where no genetic cause can be found and other features suggestive of Barth Syndrome are present.

Routine blood testing: Cardiolipin Analysis

Cardiolipin analysis is temporarily unavailable in the UK. The laboratory at Bristol Royal Infirmary continues however to facilitate testing for Barth syndrome by forwarding samples to the Academic Medical Centre (AMC) in Amsterdam for analysis. Analysis of samples sent via the Bristol laboratory to the AMC are free of charge.

Please take 1-3 ml of whole blood collected into a K-EDTA (full blood count) tube, Monday to Thursday only and send within 24 hours of collection by first class post to the:

Metabolic, Neuroendocrine and Nutrition Laboratory

Department of Clinical Biochemistry

Bristol Royal Infirmary

Bristol

BS2 8HW

Please label the box 'Urgent clinical sample - for immediate delivery to the Metabolic, Neuroendocrine and Nutrition Laboratory'.

Alternatively a blood spot can be sent directly to The Academic Medical Centre (AMC), Amsterdam (see https://www.amc.nl).

Please note that samples sent directly to the AMC will incur a charge.

Post mortem testing

If a patient is suspected to have died as a result of Barth Syndrome, cardiolipin analysis can be performed in cultured fibroblasts (skin cells). If fibroblasts are unavailable, please contact Vicki Powers to discuss details on 0117 342 2590 or by email at: victoria.powers@UHBristol.nhs.uk

Genetic testing by TAZ Gene Sequencing

Further information on genetic testing in Bristol, and a proforma for referral of samples are given here.

The information on this page is taken from the NHS Barth Syndrome Service site – for further details please visit Barth Syndrome Service - Testing

Testing for Barth syndrome outside of the United Kingdom

Genetic testing is available in many different countries and we suggest you visit the following sites for details:

Europe: orpha.net
USA: barthsyndrome.org

Cardiolipin tests (for a fee) are also available in The Netherlands where the test was developed with financial assistance and samples provided by BS UK and BSF.

For further information please contact Dr Kulik via e-mail w.kulik@amc.uva.nl or phone (+31 0 20 566 2427)

Dr. W. Kulik (Mass Spectrometry/Metabolomics)
Clinical Biochemical Geneticist i.t.
Academic Medical Centre, University of Amsterdam
Lab. Genetic Metabolic Diseases, F0-224
P.O. Box 22700 1100 DE

AMSTERDAM
The Netherlands

Doctors

Do you suspect your patient might have Barth syndrome?

Please contact us