By following Malawian twins for their first 3 years of life, the researchers find differences in the gut microbiome of well-nourished and malnourished siblings. As infants age there is a progressive change in their gut microbiomes but the microbiome in children with kwashiorkor doesn’t seem to progress even under therapeutic nutritional intervention. Furthermore, a fecal transplant into germ-free mice fed a rural Malawi diet resulted in progressive weight loss.
Science. 2013 Feb 1;339(6119):548-54. doi: 10.1126/science.1229000
Gut Microbiomes of Malawian Twin Pairs Discordant for Kwashiorkor
Kwashiorkor, an enigmatic form of severe acute malnutrition, is the consequence of inadequate nutrient intake plus additional environmental insults. To investigate the role of the gut microbiome, we studied 317 Malawian twin pairs during the first 3 years of life. During this time, half of the twin pairs remained well nourished, whereas 43% became discordant, and 7% manifested concordance for acute malnutrition. Both children in twin pairs discordant for kwashiorkor were treated with a peanut-based, ready-to-use therapeutic food (RUTF). Time-series metagenomic studies revealed that RUTF produced a transient maturation of metabolic functions in kwashiorkor gut microbiomes that regressed when administration of RUTF was stopped. Previously frozen fecal communities from several discordant pairs were each transplanted into gnotobiotic mice. The combination of Malawian diet and kwashiorkor microbiome produced marked weight loss in recipient mice, accompanied by perturbations in amino acid, carbohydrate, and intermediary metabolism that were only transiently ameliorated with RUTF. These findings implicate the gut microbiome as a causal factor in kwashiorkor.