Growth of infants born to HIV-infected women, when fed a biologically acidified starter formula with and without probiotics

Objectives: To compare the growth of HIV-exposed uninfected infants fed a biologically acidified milk formula with or without probiotics (Bifidobacterium lactis) during the first six months of life, with control infants fed a standard starter formula. Design: Multi-centre, double-blinded randomised controlled trial. Setting: Infants born to HIV-infected women delivering at one of three academic hospitals in Johannesburg, South Africa. Subjects: Consenting HIV-positive women, who had previously decided not to breast-feed, were randomised to receive one of three milk formulas for their newborn infants. Outcome measures: Comparisons of growth parameters through the first four months of life were made between infants fed the acidified formula without probiotics and those fed the control formula (“acidification effect”), and between infants fed the acidified formulas with and without added probiotics (“probiotic effect”). Results: Of 131 randomised infants, 33 (25%) did not complete the study and 13 (10%) were HIV infected, leaving 85 infants available for analysis. Infants receiving the acidified formula with probiotics had more rapid head growth (p=0.04) and showed a trend towards more rapid weight gain (p=0.06) over the first four months of life than the infants receiving the acidified formula without probiotics. No other significant differences between the feeding groups were demonstrated. Conclusions: Infants in all study groups grew well, with increased head growth and a trend towards increased weight gain for those receiving probiotics. There were no differences in morbidity between the three study groups and no evidence of adverse effects of the study formulas. SAJCN Vol. 21 (1) 2008: pp. 28-3

Growth of infants born to HIV-positive mothers fed a whey-adapted acidified starter formula with prebiotics and nucleotides

Objectives: The objectives of this study were to evaluate whether infants born to known HIV-positive mothers, but who were not themselves infected with HIV and who were fed a chemically acidified starter formula with prebiotics with or without nucleotides during their first six months, displayed growth rates equal to uninfected infants fed a chemically acidified starter formula without prebiotics or nucleotides.Design: The design was a multi-centre, double-blinded randomised controlled trial.Setting: The study was carried out in four academic hospitals, three in Johannesburg and one in Cape Town, South Africa.Subjects and intervention: The subjects were newborn infants born to consenting HIV-positive women who had previously decided not to breast feed. The infants were randomised to receive one of three milk formulas. The intervention comprised chemically acidified formula without prebiotics or nucleotides, with prebiotics only, or with prebiotics and nucleotides.Outcome measures: The outcome measures were the growth parameters through the first six months of life.Results: Of the 150 randomised infants, 50 did not complete the study and 16 (12.8% of those tested) were infected with HIV, leaving 84 infants available for analysis. All three formulas were tolerated well, with no differences in growth parameters seen with the addition of prebiotics and nucleotides. The growth rates of the study infants up to the age of six months were very good, showing an increase in Z-scores from negative values at the time of enrolment in the first week after birth to around zero for length and > 0.5 for weight.Conclusions: The three chemically acidified formulas were tolerated well and resulted in good growth over the first six months of life. No benefits were seen with the addition of prebiotics or nucleotides. The growth rates were similar to those found in previous studies of ours on biologically acidified formulas. The chemical acidification of infant formulas appears to be a realistic alternative to biological acidification should an acidified formula be required.Keywords: milk formula; acidification; probiotics; nucleotides; infant growt

The non-clonality of drug resistance in Beijing-genotype isolates of Mycobacterium tuberculosis from the Western Cape of South Africa

Background. The Beijing genotype of M. tuberculosis is a virulent strain that is disseminating worldwide and has a strong association with drug resistance. In the Western Cape of South Africa, epidemiological studies have identified the R220 cluster of the Beijing genotype as a major contributor to a recent outbreak of drug-resistant tuberculosis. Although the outbreak is considered to be due to clonal transmission, the relationship among drug resistant isolates has not yet been established. Results. To better understand the evolution of drug resistance among these strains, 14 drug-resistant clinical isolates of the Beijing genotype were sequenced by whole-genome sequencing, including eight from R220 and six from a more ancestral Beijing cluster, R86, for comparison. While each cluster shares a distinct resistance mutation for isoniazid, mapping of other drug-resistance mutations onto a phylogenetic tree constructed from single nucleotide polymorphisms shows that resistance mutations to many drugs have arisen multiple times independently within each cluster of isolates. Thus, drug resistance among these isolates appears to be acquired, not clonally derived. This observation suggests that, although the Beijing genotype as a whole might have selective advantages enabling its rapid dissemination, the XDR isolates are relatively less fit and do not propagate well. Although it has been hypothesized that the increased frequency of drug resistance in some Beijing lineages might be caused by a mutator phenotype, no significant shift in synonymous substitution patterns is observed in the genomes. Conclusion. While MDR-TB is spreading by transmission in the Western Cape, our data suggests that further drug resistance (i.e. XDR-TB) at this stage is acquired.Peer Reviewe

Survival of very-low-birth-weight infants according to birth weight and gestational age in a public hospital

Objectives. To determine the survival rates for infants weighing 500 - 1 499 g according to birth weight  (BW) and gestational age (GA).Design. This was a retrospective cohort study. Pregnancy and delivery data were collected soon after birth and neonatal data at discharge or at death.Setting. Chris Hani Baragwanath Hospital (CHBH), a publicsector referral hospital, affiliated to the  University of the Witwatersrand.Subjects. Live births weighing between 500 g and 1 499 g delivered at or admitted to CHBH from January 2000 to December 2002.Outcome measures. BW and GA-specific survival rates for all live infants born at CHBH and for those admitted for neonatal care.Results. Seventy-two per cent of infants survived until discharge. The survival to discharge rate was  32% for infants weighing < 1 000 g, and 84% for those weighing 1 000 - 1 499 g. Survival rates at 26, 27 and 28 weeks' gestation were 38%, 50% and 65% respectively. Survival rates for infants admitted to the neonatal unit were better than rates for all live births, especially among those weighing < 1 000 g or with a GA < 28 weeks. There was a marked increase in  survival between the 900 - 999 g and 1 000 - 1 099 g weight groups. Provision of antenatal care, caesarean section, female gender and an Apgar score more than 5 at 1 or 5 minutes were associated with better survival to hospital discharge. Conclusion. Survival among infants weighing less than 1 000 g is poor. In addition to severe  prematurity, the poor survival among these infants(< 1 000 g) is most likely related to the fact that they were not offered mechanical ventilation. Mechanical ventilation should be offered to infants weighing < 1 000 g as it may improve their survival even in institutions with limited resources