Iron supplementation in previously anemic Bolivian children normalized hematologic parameters, but not immunologic parameters.

Iron deficiency anemia (IDA) is considered to be the most prevalent micronutrient deficiency in the world. Estimates indicate that 1.2 billion people suffer mild to severe forms of anemia and that up to 46% of schoolchildren in developing countries are affected. In 2003, ENDSA, the national demographic and health survey of Bolivia showed that 60% of children under five and 72% of children under 2 years old were anemic. Micronutrient deficiency has been suggested to impair cell-mediated immunity. In particular, iron, zinc and vitamin A deficiencies have an impact on the immune system. In vitro and in vivo laboratory studies indicate a link between iron deficiency and impaired T-lymphocyte proliferation. The exact effects or mechanisms of iron deficiency on maturation and proliferation of T-lymphocytes in vivo are, however, not yet known. This study investigated the effects of iron on the maturation of T-lymphocytes in anemic but otherwise healthy schoolchildren (no apparent protein-energy deficiency or other morbidity). Anemic children of a poor peri-urban school of Cochabamba city, Bolivia, were given iron treatment for three consecutive months. We chose to look at CD1a+ lymphocytes, which are immature thymocytes. The proportions of CD1a+ lymphocytes in the peripheral circulation measured at baseline and after treatment were compared with a reference group of age-matched non-anemic children controls from the same school. The immunologic parameters, although improved, did not reach the proportions of the control group. Overall, the proportion of circulating immature T-lymphocytes decreased from 18.3% to 9.2% in the treated following iron supplementation in anemic children, compared with 3.4% in non-anemic children.

Do growth monitoring and promotion programs answer the performance criteria of a screening program? A critical analysis based on a systematic review.

OBJECTIVE: Growth Monitoring and Promotion programs (GMP) have been intensively promoted to improve children's health in developing countries. It has been hoped that regularly weighing children would result in the early detection of growth falterers, and that the growth chart would serve as an educational tool to make that state apparent to both health workers and caretakers in order to trigger improved caring practices. Our objective was to review whether GMP answers the theoretical grounds of a screening and intervention program. METHOD: A systematic literature review was performed. The WHO framework developed by Wilson and Jungner for planning and evaluating screening programs guided the analysis. RESULTS: Sixty-nine studies were retrieved. Overall, evidence is weak on the performance of GMP as a screening program for malnutrition through early detection of growth falterers. The main results are: (1) malnutrition remains a public health problem, but its importance is context specific; (2) the value of a low weight velocity to predict malnutrition is unknown and likely to vary in different contexts; (3) the performance of GMP for improving nutrition status of children and in reducing mortality and morbidity is unknown; (4) the performance of the screening is affected by the unreliability of weight measurements; (5) the promotional and educational effectiveness of GMP is low, in particular the growth chart is poorly understood by mothers; (6) the acceptability seems low in regards of low attendance rates; (7) evidence is lacking regarding cost-effectiveness. CONCLUSIONS: We conclude that there is too little scientific evidence to indiscriminately support international promotion of GMP. However GMP could constitute a valid strategy of public nutrition in specific situations. We indicate paths for further research and how prevention programs could be developed.