[Mitochondrial myopathy (mono- and multisystem mitochondrial diseases)].

Four mitochondrial myopathy cases are reported. In addition to complaints, clinical and laboratory findings the changes in number, size, shape and in structure of the mitochondria in skeletal muscles are detailed. In three of their cases the disease is monosystemic, one case seems to be multisystemic in character: beside the morphologically proven muscle and liver changes it is likely that cardiac muscle and the central nervous system is also affected on the base of the clinical symptoms.