Areas of Research
Maternal and Child Health
Enhancement of child survival is the most cost-effective tool for development of the country. The clinical division of National Institute of Nutrition works towards this goal through focused research on nutrition, immunity and infection among children and pregnant women.
The Clinical Division plays a key role in most of the regular activities of the Institute particularly in the training, advisory and consultancy services provided by the Institute to the government and other organizations.
Yet another major responsibility of the Division is rendering nutritional rehabilitation services to
malnourished children suffering from various nutrition deficiency disorders and to
the pregnant women by providing inpatient treatment at the two major
hospitals meant for women and children.
1. Interactions between nutrition, infection and immunity in children
a) Protein Energy Malnutrition (PEM) and Immune system: Effects of major nutritional problems on immune system and their interaction with infectious diseases were the major issues addressed. The results show impaired neutrophil and macrophage function. The cell-mediated immunity and specific antibody response to certain vaccines are also impaired. However, serum immunoglobulin levels remain normal in PEM. T cell subset response as measured by cytokines show poor response of IL-2 in PEM children, though IL-4, IL-5, IL-10 and IFN- g are within normal limits. Rehabilitation of children with kwashiorkor failed to restore T cell numbers to normal level, several years after the acute episode. Response to vaccine is adequate in mild / moderate PEM.
b) Vitamin A and Immunity: Vitamin A deficient children show low levels of circulating T cells, and a proportionate decrease in CD4 and CD8 cells. Humoral immunity and innate immunity are not affected in mild vitamin A deficiency. Vitamin A shows adjuvant functions on H2O2, and IL-1 production and antibody response to diphtheria, tetanus and measles vaccines, when given in large doses.
c) Tuberculosis - Nutrition - Immunity: Tuberculosis infection has immuno-suppressive effect. When malnutrition and tuberculosis coexist, the severely malnourished children have more serious consequences of immuno-suppression.
d) Iron Deficiency and Immunity: Iron deficiency anemia (IDA) impairs both innate and cell mediated immune functions. B cell number and antibody response to diphtheria and tetanus are not altered. The IL2 cytokine of TH1 subset is impaired in IDA. In contrast IFN GAMMA AND IL4are not altered. Treament of IDA with iron restores immune function to normal.
e) RSV in children: Respiratory syncitial virus (RSV) infection in children with acute pneumonia/bronchiolitis: RSV infection was detected by direct antigen detection immunofluorescent assay during the peak season, August to December. Significantly higher proportions of younger infants and infants with bronchiolitis were infected with RSV compared to older infants and those with pneumonia.
f) TNF- a in malnourished children with acute bacterial meningitis (ABM): ABM in children showed 40%, 14% and 12% of the infection with streptococcus pneumonia, Neisseria meningititis and haemophilus influenza respectively. TNF-a, a cytokine, implicated in the adverse outcome of ABM, is high even in undernourished children with ABM.
2. Micronutients and Child health
a) Zinc: Zinc deficiency has been found in association with PEM in children. Severe zinc deficiency was observed in children suffering from kwashiorkor and marasmus while undernourished children suffered from mild zinc deficiency. The consequences of mild zinc deficiency need further exploration.
b) Measles and vitamain A (VA): Co-administration of VA with measles vaccine to 9-month-old infants was found to enhance seroconversion rates and also improve VA status of the infant.
c) Safety, feasibility and impact of administering high dose VA with OPV-Orissa: Linking VA administration to NIDs was seen to be safe and feasible as studied in Orissa and coverage was extremely high. Clinical VAD is a problem of public health significance in Orissa and bordering Andhra Pradesh. VA administration in Orissa had a significant impact on VAD but could not sustain the effect beyond 4 months.
d) Breast milk and Vitamin A: Vitamin A status of infants did not improve after a massive dose of vitamin A (2 lakhs I.U) to women soon after delivery.
3. Maternal Health and Nutrition
a) Changes in fat composition during pregnancy and its relation to birth weight: Low birth weight (LBW) infants showed higher percentage of fat compared to normal birth weight infants.
b) Food based vitamin A supplementation during pregnancy: Sub-clinical vitamin A deficiency (VAD) was observed in >26% of the women (including HSES group).
Red palm oil (RPO) supplementation: RPO supplementation significantly improved maternal and neonatal vitamin A status and reduced the prevalence of maternal anemia. Thus, RPO, a rich source of vitamin A could be used as a dietary approach for improving vitamin A status of pregnant women and their infants.
Spirulina supplementation in pregnant women showed: significant increase in serum retinol concentration in both the mother and the infant and significant increase in birth weight and gestational age with lower preterm deliveries.
c) Maternal nutritional status in early pregnancy: The effects of maternal nutritional status on placental development and its role in intra uterine fetal growth pattern pregnancy outcome.
3. Maternal infections and pregnancy outcome
a) Although the role of infections involving the reproductive tract in adverse pregnancy outcome is well established in western literature, it has not been explored in women of low-income group. A study was undertaken in low and high-risk pregnant women of low and high-income groups. Chlamydia trachomatis and Toxoplasmosis were the most common infections and were associated with prematurity and premature rupture of membranes. Among the high-risk women, chlamydia emerged as major threat to poor pregnancy outcome. In addition, chlamydia was of higher prevalence in pregnant women of low-income group compared to high-income group of women, with higher prematurity among the seropositives, of low-income group.
b) Avidity ELISA: Avidity ELISA is a novel test developed recently to distinguish acute Vs chronic asymptomatic infections like toxoplasmosis, rubella. The usefulness of this technique was tested in our laboratory in a sub-sample of pregnant women, seropositive for toxoplasmosis specific IgM / IgG antibodies.
c) Local immune responses to Vaginal Infections (Bacterial vaginosis, Candidiasis, and Trichomoniasis) in undernourished women indicated adequate IgA levels, albeit greater degradation in those with bacterial vaginosis. Also a type II local cytokine response was observed in these women vaginal infections were found to be highly prevalent in non pregnant and pregnant women, BV being the most prevalent.