[Mucoviscidosis discovered after the age of 25 years. Review and follow-up of cases of the literature].

We report a case of cystic fibrosis diagnosed in a 27-year-old man complaining of diarrhoea which was present for 2 years. The diagnosis was suspected upon the association of exocrine pancreatic insufficiency, massive hepatic steatosis, pulmonary infiltrates on chest radiograph, and moderate alterations of pulmonary function tests. It was confirmed by positive sweat tests. Study of the cystic fibrosis gene demonstrated a compound heterozygosity for delta F508 deletion and for mutation W1282X. Diagnosis of cystic fibrosis after the age of 25 is a rare event and the 25 hitherto published case reports are analysed after obtention of more detailed information for the authors. The existence of cases of late diagnosis might be explained by genetic heterogeneity.