Vitamin A status of children in the urban slums of Karachi, Pakistan, assessed by clinical, dietary, and biochemical methods.

We assessed the vitamin A status of 532 children with an age range of 6-60 months who were living in slum areas of Karachi, Pakistan, using three methodologies: clinical eye examination, dietary vitamin A intake, and serum retinol level. No definite clinical signs of xerophthalmia were observed in any of these children. The mean +/- SD vitamin A intake estimated from a food frequency questionnaire for the group with inadequate (low and deficient) serum retinol levels (< 20 micrograms/dl) was 362 +/- 332 retinol equivalents (RE) compared with 431 +/- 332) RE in the group with adequate serum levels (P < 0.005). Deficient serum retinol levels (< 10 micrograms/dl) were present in 12 children (2%); two of these had a healed corneal scar. Low serum retinol levels (10-19 micrograms/dl) were present in 46%, while 51% children had adequate levels (> or = 20 micrograms/dl). The mean +/- SD serum retinol level for the inadequate (< 20 micrograms/dl) and adequate groups were 15.3 +/- 2.8 and 26.6 +/- 6.7 micrograms/dl, respectively. These results suggest that a significant number of children in these communities have low vitamin A levels and thus may constitute an at risk group. These results also suggest that the dietary intake method may be a simple and inexpensive screening tool for assessment of vitamin A status in communities.