Environmental Enteropathy: Elusive but Significant Subclinical Abnormalities in Developing Countries

Environmental enteropathy/Environmental enteric dysfunction (EE/EED) is a chronic disease of small intestine characterized by gut inflammation and barrier disruption, malabsorption and systemic inflammation in the absence of diarrhea. It is predominantly diseases of children in low income countries and is hypothesized to be caused by continuous exposure to fecally contaminated food, water and fomites. It had not been recognized as a priority health issue because it does not cause overt symptoms and was seen in apparently healthy individuals. However, there is a growing concern of EE/EED because of its impact on longitudinal public health issues, such as growth faltering, oral vaccine low efficacy and poor neurocognitive development. Recent works have provided important clues to unravel its complex pathogenesis, and suggest possible strategies for controlling EE/EED. However, effective diagnostic methods and interventions remain unsettled. Here, we review the existing literature, especially about its pathogenesis, and discuss a solution for children living in the developing world. •EE/EED is acquired by the close contact with unsanitary condition, and abnormalities of EE/EED are reversible over time.•EE/EED should be diagnosed as young as possible because poor growth is often evident within 1-2 years of life.•EE/EED should be diagnosed by simple, noninvasive and low-cost methods, such as fecal biomarkers.•It is hard to diagnose EE/EED and to predict consequences by a single marker/test due to the complexity in pathogenesis.•Interventions for EE/EED other than sanitary reform are under investigation although no reports showed favorable outcomes currently.