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18 | InTouch WINTER 2025 MELAS SYNDROME in a mitochondrial gene and occurs in people with no family history of MELAS which is now able to be passed on. Diagnosis of MELAS • The diagnosis of MELAS is usually determined by clinical examination. However, confirmation of the diagnosis usually requires molecular, genetic testing and a muscle or brain biopsy. The muscle biopsy shows characteristic ragged fibres for MELAS syndrome and a brain biopsy shows the stroke-like changes. • The clinical diagnosis of MELAS is based on the following features: • Stroke-like symptoms, typically before the age of 40 • Encephalopathy with seizures and/ or dementia • Mitochondrial myopathy, evidenced by lactic acidosis and/or ragged red fibers on muscle biopsy. • To confirm the diagnosis, two of the following are also required: • Normal early psychomotor development • Recurrent headache • Recurrent vomiting Management There is no known treatment for MELAS syndrome, however, patients are managed according to what areas of the body are affected at a particular time. Sensorineural hearing loss has been treated with cochlear implantations; Anti-convulsant drugs are used to help prevent and control seizures associated with MELAS syndrome (it is important to note that Valproic acid should not be used as an anticonvulsant); Diabetes mellitus is managed by dietary modification, oral hypoglycemic agents or insulin therapy; Migraine headaches and cardiac manifestations are treated in the usual manner i.e. with pain relief medication or preventive medications; and the use of L-arginine has been reported to improve the symptoms of disease during the acute stroke-like episode. Antioxidants and vitamins have also been used, however, consistent success hasn’t been reported. Therapies are sometimes used to increase energy production by the mitochondria and slow down the effects of the condition. Coenzyme q10 and L-carnitine have been beneficial in some patients. Individuals with MELAS should also receive standard childhood vaccinations such as the flu vaccine and pneumococcal vaccine. This is because feverish illnesses may make the condition worse. In general, for patients with mitochondrial myopathies, moderate treadmill training may be beneficial for maintaining muscles strength and endurance. Genetic counselling is also recommended for affected individuals and their families. Agents to avoid: Mitochondrial toxins including aminoglycoside antibiotics, linezolid, cigarettes and alcohol; Valproic acid for seizure treatment; dichloroacetate (DCA) due to increased risk for peripheral neuropathy. Therapies are sometimes used to increase energy production by the mitochondria and slow down the effects of the condition. Continued from previous page. Pregnancy management: Affected or at-risk pregnant women should be monitored for diabetes mellitus and respiratory insufficiency. This may require therapeutic interventions. Support The MDA Fieldworkers are available for support. They have in-depth knowledge of a range of neuromuscular conditions, and will have a better understanding of your needs and challenges. Have a chat over the phone or they can come to you for a kanohi ki te kanohi/face- to-face visit. They may have some real practical suggestions that have worked for others to offer as well. This service is offered free of charge to MDA members and is funded through donations and grants. Contact your local branch to be put in contact with your Fieldworker. Information in this factsheet was sourced from: http://www.ncbi.nlm.nih.gov/books/ NBK1233/ http://emedicine.medscape. com/article/946864-clinical#b5 https://ghr.nlm.nih.gov/condition/ mitochondrial-encephalomyopathy- lactic-acidosis-ndstroke-like-episodes http://www.medicinenet.com/ melas_syndrome/article.htm http:// rarediseases.org/rare-diseases/melas- syndrome/ https://www.mda.org/ disease/mitochondrial-myopathies