Myopathy is the most common presenting symptom and rhabdomyolysis may develop.

Stroke-like episodes always ensue other symptoms and in 58% are preceded by migraines.

Any symptom of MELAS may come first and intersymptom interval may reach up to 28 years.

Juvenile form has a higher mortality rate than adult form of the disease.

Even mono and oligosymptomatic patients should be taken into consideration for MELAS.