Environmental enteropathy

Environmental enteropathy, also known as tropical enteropathy or environmental enteric dysfunction (EED), is a condition or subclinical disorder believed to be due to frequent intestinal infections. There are often minimal acute symptoms. There may be chronic problems with absorbing nutrients which may result in malnutrition and growth stunting in children. It may be the chronic form of tropical sprue which is usually brief and presents with diarrhea. Environmental enteropathy results in a number of changes in the intestines including: smaller villi, larger crypts (called crypt hyperplasia), increased permeability, and inflammatory cell build-up within the intestines. These changes result in poor absorption of food, vitamins and minerals – or "modest malabsorption".

Environmental enteropathy is believed to result in chronic malnutrition and subsequent growth stunting (low height-for-age measurement) as well as other child development deficits. Especially the first two years (and the prior 9 months of fetal life) are critical for linear growth and maybe even more importantly brain development. Stunting is an easy to measure symptom of these child development deficits, and the effects have been found to be mostly irreversible. Furthermore, contrary to the negative impacts of diarrheal episodes on the growth of children below the age of two, which can usually be overcome in between these episodes (given adequate nutrition), the chronic effects of environmental enteropathy are not recovered from easily.

Many oral vaccines, both live and non-living, have proven to be less immunogenic or less protective when administered to infants, children or adults living in low socioeconomic conditions in developing countries than they are when used in industrialized countries. Widespread environmental enteropathy is hypothised to be one of the causes for this.

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