Assessment of vitamin A status with the relative-dose-response test in Peruvian children recovering from pneumonia.

摘要

BACKGROUND: The relative-dose-response (RDR) test is used to identify subjects with marginal liver vitamin A stores, but its use has not been evaluated during episodes of infection. OBJECTIVE: The objective was to assess, with the RDR test, the vitamin A status of children recovering from pneumonia. DESIGN: As part of a double-blind, placebo-controlled clinical trial of high-dose vitamin A supplements among children hospitalized with pneumonia in Lima, Peru, we examined the association of treatment group, nutritional status, severity of disease, and induction of the acute phase response on the basis of serum C-reactive protein (CRP) on serum retinol and the RDR test. RESULTS: Serum retinol was low at admission and increased significantly in both the vitamin A and placebo groups during recovery. Serum CRP had a significant, inverse association with retinol at both admission and discharge. Serum retinol and CRP concentrations never differed significantly between the treatment groups. Among subjects with CRP > or =10 mg/L, 21 in the vitamin A group and 20 in the placebo groups (P = 0.83) had a positive RDR test result. Among subjects with CRP <10 mg/L, 56 in the placebo group but only 6 in the vitamin A group had positive RDR test results (P = 0.002). CONCLUSION: The RDR test was useful in assessing the vitamin A status of children recovering from pneumonia when CRP concentrations were <10 mg/L but not when CRP concentrations were higher.