Validation of anthropometric and bioelectrical impedance analysis (BIA) equations to predict total body water in a group of Cameroonian preschool children using deuterium dilution method

BACKGROUND: Little information is available on the validity of anthropometry or impedance-based equations for prediction of total body water (TBW) in African children. This study was designed to validate and develop equations to predict total body water in Cameroonian children. METHODS: TBW was measured by deuterium dilution in 102 children between 24 and 60 months of age and compared with the ones predicted by 5 anthropometric and 7 BIA equations. Multiple linear regression analysis was used to develop prediction equations for TBW from anthropometric parameters. RESULTS: Unacceptable discrepancies in the estimates of TBW at individual level were noted with all the equations tested. The following new anthropometry and BIA equations for the estimation of TBW were respectively developed: TBW = 6.488 + 0.434 × sex−0.039 × age + 0.670 × weight−0.081 × MUAC (cm)−0.372 × BMI (adjustedR2= 0.71,RMSE = 3.6), and TBW =−6.206 + 0.0037 × height2/Z−0.041 × age + 0.265 × weight + 0.1214 × height (adjustedR2=0.68, RMSE = 1.4). The cross-validation procedures revealed that the predicted values of TBW compared with measured values are accurate at a group level. CONCLUSION: The current published anthropometric and BIA equations are invalid for the estimation of TBW in Cameroonian preschool children. The newly developed anthropometry or BIA prediction equations are valid for use in Cameroonian children aged 24­60 months

Prevalence and Identification of Serum Markers Associated with Vertical Transmission of Hepatitis B in Pregnant Women in Yaounde, Cameroon.

OBJECTIVE: To determine the prevalence of Hepatitis B Virus (HBV) infection in pregnant women and identify markers associated with vertical transmission of HBV. METHODS: Prospective and cross-sectional study over 10 months on 298 pregnant women attending antenatal clinics in the Cité Verte and Efoulan District hospitals in Cameroon. A dry tube blood collection was performed on all pregnant women and babies born to HBsAg-positive mothers. Serum from the women was used to test for HBsAg through immunochromatography and then confirmed by ELISA. The test for HBeAg, HBeAb and HBcAb and dosage of transaminases were performed on the serum of HBsAg-positive women. Only HBsAg was tested in babies within 24 hours after birth. RESULTS: HBsAg was present in 23 (7.7%) mothers while 275 (92.3%) tested negative. Due to loss to follow-up, we assessed vertical transmission in 20 babies born to20 mothers. In all, eight babies tested HBsAg-positive; six mothers tested positive with HBeAg; 10 mothers with HBeAb and two were simultaneously infected with HBV and HIV. CONCLUSION AND GLOBAL HEALTH IMPLICATIONS: HBeAg and increase in liver transaminases were serum markers associated with the vertical transmission of HBV while HBeAb and anti-HIV therapy were protective markers. There is need to systematically screen all pregnant women for hepatitis B, follow up those that are positive, and administer a dose of gammaglobulin anti-HBs to their children to reduce the risks of chronic hepatitis and hepatocellular carcinoma (CHC) and curb mortality and morbidity due to viral hepatitis B.