T-lymphocyte subsets and prolonged diarrhea in young children from Guinea-Bissau.

In a community-based prospective study of 380 children conducted between 1987 and 1990, the rate of diarrhea was significantly associated with percentage of CD8 T-lymphocytes and the CD4:CD8 ratio. After adjustment for age and previous diarrhea, the relative incidence of diarrhea with a duration of > or = 7 days was 2.10 (95% confidence interval (CI) 1.15-3.85) in children with 20-29.9% CD8 T-cells and 3.41 (95% CI 1.29-9.01) in children with > or = 30% CD8 T-cells (in comparison with children who had less than 20% CD8 cells) (p for trend = 0.004). There was a nonsignificant tendency for rates of diarrhea of > or = 7 days to decrease according to increasing proportions of CD4 cells (p = 0.194). The authors found no significant association between T-cell subsets and diarrhea which resolved within 6 days. The association between the incidence of prolonged diarrhea and T-cell subset proportions could not be explained as a confounding effect of low weight, breastfeeding, or previous infection with measles or Cryptosporidium. However, other prior infections or micronutrient deficiencies may explain the findings, and these host factors may be significant targets in intervention against diarrheal diseases.