This article, from The Gordon Lab at Washington University in St. Louis, investigated the gut microbiota of Bangladeshi children who had experienced severe acute malnutrition (SAM). SAM is defined by anthropometric measurements; those children with weight-for-height Z-scores (WHZ) below three standard deviations from the median of the World Health Organisation (WHO) reference growth standards are considered as suffering from SAM. As food is considered a key factor in shaping the organisms of the gut microbial community, the researchers hypothesized that healthy postnatal development of the gut microbiota could be perturbed in malnutrition.
To test this hypothesis, the researchers began by taking faecal samples from 50 healthy Bangladeshi children during the first two years of life. In addition, 64 children presenting SAM were enrolled in a randomized therapeutic food interventional trial, with two different types of food intervention, where faecal samples were collected before, during and at the end of each nutritional intervention. In both cases, the relative microbiota maturity index was determined, finding out the proportional representation of bacterial species in the samples.
The researchers found that children who had experienced SAM showed immaturity of the gut microbiota, which only partially improved following nutritional intervention. There was evidence that less severe forms of malnutrition also had an effect on the microbiota. The authors say that microbiota maturity indices may be used as a measure of postnatal development, and also a way of classifying states of malnourishment and judging the efficacy of intervention.
Subramanian S et al. (2014) Persistent gut microbiota immaturity in malnourished Bangladeshi children Nature 570(7505), pp. 417-421. doi:10.1038/nature13421