[Myoglobinuria and carnitine palmitoyltransferase deficiency. Diagnostic procedure and differential diagnosis]

Carnitine palmitoyltransferase (CPT) deficiency is the most common metabolic cause of recurrent myoglobinuria. We describe five patients with CPT deficiency who were recruited during a 24-months period. Phenotypic expression ranged from mild myalgia without myoglobinuria to severe exercise-induced attacks and a lethal course. The pathophysiological basis of the clinical heterogeneity is discussed. The diagnostic procedure includes a neurological and electromyographical examination as well as an exercise test and extensive biochemical investigations of muscle biopsy specimens. Accurate diagnosis allows an early introduction of preventive measures and clearly improves the outcome.