Assessment of preclinical vitamin A deficiency in children with persistent diarrhea.

To explore the relationship between vitamin A deficiency and persistent diarrhea among young children, we studied the vitamin A status of 23 children greater than 5 years of age with persistent diarrhea by performing conjunctival impression cytology (CIC) and the relative dose-response test (RDR) as a measure of liver reserve of vitamin A. The control group consisted of 23 age- and sex-matched children who were otherwise healthy in whom CIC was performed and fasting plasma retinol values were determined. The criteria for vitamin A deficiency in CIC were paucity of goblet cells and scanty, abnormal epithelial cells. None of these children had ocular manifestations of vitamin A deficiency. Among the children with persistent diarrhea, CIC characteristic of vitamin A deficiency was found in 17 (group 1) and CIC results were normal in six (group 2). In group 1, the serum retinol levels were 1 +/- 1 microgram/dl, and RDR was 88 +/- 14. In group 2, the serum retinol levels were 8 +/- 4 micrograms/dl (p less than 0.001) and the RDR was 16 +/- 12 (p less than 0.001). In the control group, the CIC results were normal in all the children and the plasma retinol levels in these children were 19 +/- 8 micrograms/dl. In conclusion, 17 of 23 children with persistent diarrhea had abnormal CIC results, significantly low serum retinol levels, and significantly high RDR results, although they had not yet manifested xerophthalmia.(ABSTRACT TRUNCATED AT 250 WORDS)