Myoadenylate deaminase deficiency with severe rhabdomyolysis

A 13-year-old Turkish girl was admitted because of recurrent episodes of muscle pain and weakness since the age of 5 years. As an outpatient she developed severe acute rhabdomyolysis (myoglobinuria and increased serum creatine kinase level of 19,000 units/l). The acute rhabdomyolysis and the preceding episodes of muscle pain and weakness had been induced by exercise. There was no increase in plasma ammonia level during ischaemic forearm exercise test and bicycle ergometry. Myoadenylate deaminase deficiency was proven both histochemically and biochemically. The girl was found to be homozygous for the C 34-T mutation of the AMPD1 gene causing primary myoadenylate deaminase deficiency in skeletal muscle. Both parents and her brother were heterozygous for that mutation. Myoadenylate deaminase deficiency has to be considered as a cause of severe rhabdomyolysis.