[Cystinosis: an infrequent cause of distal myopathy].

INTRODUCTION

Cystinosis is a hereditary disease with clinical symptoms that are caused by the accumulation of cystine crystals in different tissues. Distal vacuolar myopathy has been reported as one of its later complications.

CASE REPORT: Here, we present the case of a 20-year-old male diagnosed with cystinosis at the age of 2 years, with severe renal involvement that required a transplant. The patient gradually developed weakness and atrophy of the muscles in his hands. Neurophysiological and histological studies enabled a diagnosis of distal vacuolar myopathy to be established, and electron microscopy revealed deposits of cystine crystals.

CONCLUSIONS

Cystinosis must be included within the differential diagnosis of distal myopathies. Timely treatment with cysteamine could prevent the development of this complication.