[Differential diagnosis of Friedreich ataxia].

The clinical records of 72 patients with spinocerebellar ataxias which had manifested before the age of 20, were examined in a retrospective study. Depending on whether the muscle stretch reflexes in the legs were positive or negative, two groups were distinguished, that of early onset cerebellar ataxia with retained tendon reflexes (EOCA) (13 P.) and that of Friedreich's ataxia (FA) (59 P.). The clinical course was much worse in the FA patients compared with EOCA. Cardiomyopathy and diabetes mellitus were not a feature of EOCA. Scoliosis and a disturbed position sense in the toes were more frequent in FA cases. The striking differences in clinical signs and course of the diseases justify the differentiation of EOCA from FA, as suggested by Harding in 1981.