The finding of vitamin A deficiency following a gastrointestinal resection is rare. A case published in 1979 described a morbidly obese 15 year old who underwent a partial jejuno-ileal bypass with a subsequent 45 kilogram weight loss. Two years following her surgery, she developed inflammatory horny lesions on the knees and elbows, followed by night blindness. Laboratory findings showed marginally low vitamin A and markedly low ß-carotene levels. Hyperkeratosis and horny plugging of dilated follicles with rare areas of parakeratosis, as well as a dermal mononuclear infiltrate, were present histologically. The dermatologic and opthamalogic symptoms cleared over two months following aggressive oral vitamin A supplementation.
The effect of vitamin A deficiency on squamous epithelial maturation can have significant clinical sequelae, particularly xeropthalmia and blindness. Because of the sensitivity of the conjunctival epithelium to low vitamin A levels, several studies have used impression cytology from the conjunctiva to detect subclinical vitamin A deficiency.