VITAMIN-A-DEFICIENCY AND NOCTURNAL VISION IN TEENAGERS WITH CYSTIC-FIBROSIS

The aim of this study was to document plasma retinol status and noctur nal vision in ten eutrophic adolescents with cystic fibrosis (CF) rece iving daily retinol supplementation. Plasma retinol, alpha and beta ca rotenes and retinol binding protein were measured in ten clinically st able CF patients (mean age: 14.3 years; Shwachman score: 80-100). Noct urnal vision evaluation was performed with a Beyne optometer. Plasma r etinol (mean 0.42 +/- 0.16 mg/l), alpha carotene and beta carotene lev els were below the lower limit of normal in all but one patient. Five out of ten patients with normal standard opthalmological examination p resented a poor (n = 3 patients) or a pathological (n = 2) dark adapta tion test. These two patients showed a dramatic increase in nocturnal vision after 1 year of adapted retinol supplementation. Conclusion Low vitamin A levels occur frequently in clinically stable, eutrophic and retinol supplemented CF adolescents. Since vitamin A deficiency is as sociated with poor nocturnal vision and since this pattern can be reve rsed by adapted retinol supplementation, we recommend monitoring plasm a vitamin A levels in CF patients and evaluation of dark adaptation in retinol deficient patients.