BARTH SYNDROME with a new mutation without cardial involvement

Introduction: The Barth syndrome (MIM#302060) is a rare X-linked recessive inherited disorder, which is based on a mutation in the tafazzin gene (TAZ). The classical clinical presentation consists of a (severe) cardiomyopathy/myopathy, prepubertal growth retardation and cyclic neutropenia. Seen from a pathobiochemical point of view there is a disturbance in mitochondrial energy supply. Laboratory findings show a reduction in cardiolipin and elevated monolysocardiolipin in the mitochondria.

Case report: An eight year old boy, who was seen in our department at the age of 3 ½ years with groß motor delay and dystrophy (length, weight, head circumference <3. centile). He showed proximal muscle weakness, normal level of CK; sonography of muscle: diminished muscle relief; normal MRI of the brain.

Lactatacidosis, elevated alanine in CSF, normal levels of organic acids in urine. Muscle biopsy: Reduction in cardiolipin and elevated monolysocardiolipin. Even at the age of eight years normal echocardiography. Confirmation of Barth syndrome via molecular genetics: a new mutation (c.654 655insGAAT; p D219fs. X220) was found.

Summary: We report about an atypical clinical presentation of Barth syndrome, which shows typical symptoms (growth retardation, mitochondrial cytopathy). At the same time other cardinal characteristics (cyclic neutropenia, cardiomyopathy) are missing. A slight increase of 3-methylglutaconic acids could be detected in urine only at the age of 7 years. Normal cholesterol levels.

Conclusion: An atypical Barth syndrome should be considered in boys with mitochondrial cytopathy and growth retardation even if cyclic neutropenia and cardiomyopathy are not present.