Role of electroretinography in the assessment of retinal function as an indicator of vitamin A status.
Hypovitaminosis A is associated with exocrine pancreatic insufficiency in cystic fibrosis. Peripheral retinal dysfunction is an early finding of vitamin A deficiency. We evaluated serum retinol and zinc as well as visual adaptation in 41 patients with cystic fibrosis, receiving generous pancreatic enzyme and micronutrient supplementation. Forty-one normal individuals matched for age and sex served as controls. Peripheral retinal function was measured by clinical electroretinography using an Electrophysiologic Personal Interfaced Computer and applying a standard protocol. Serum retinol in cystic fibrosis was significantly lower than that of the control group (0.30+/-0.01 versus 0.39+/-0.02 mg/l, p<0.001). Serum zinc concentrations were normal in the cystic fibrosis group (1.21+/-0.03 mg/l) and significantly higher than that of the control group (1.02+/-0.01 mg/l, p<0.001). The overall visual adaptation, however, was found to be normal and comparable in the two groups. It is concluded that, in cystic fibrosis, despite appropriate vitamin A supplementation, retinol serum concentration may be low. As serum retinol does not reflect vitamin A status, evaluation of visual adaptation may be a more appropriate way to monitor for vitamin A deficiency in cystic fibrosis.
Tsinopoulos
I
I
Department of Ophthalmology, Aristotle University of Thessaloniki, Greece. galtsin@otenet.gr
Nousia-Arvanitakis
S
S
Galli-Tsinopoulou
A
A
Roubies
N
N
Tentzidou
K
K
Xefteri
M
M
Stangos
N
N
D000293:Adolescent; D000328:Adult; D002648:Child; D003550:Cystic Fibrosis / Q000097:blood / Q000503:physiopathology*; D019587:Dietary Supplements; D004596:Electroretinography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D012160:Retina / Q000503:physiopathology*; D014801:Vitamin A / Q000097:blood*; D014802:Vitamin A Deficiency / Q000097:blood / Q000503:physiopathology*; D015032:Zinc / Q000097:blood
D014801:Vitamin A; D015032:Zinc