EC Gastroenterology and Digestive System

Anorexia nervosa (AN), a complex and debilitating eating disorder, is characterized by distorted personal body image and fear of gaining weight, accompanied by severe weight loss and high psychiatric comorbidity. It has difficult treatment, since it involves environmental genetic factors and alterations of the microbiome. Metabolo-psychiatric process, which leads to extreme mortality, with approximately half of the patients recovering in the very long term.

For the above reason, we delved into the topic, especially detecting the importance of fecal microbiota transplantation (FMT) in its management.

Most of the articles reviewed lead to improvement, which usually lasts up to 12 months and is directly related to the presence of specific bacterial alterations, such as Firmicutes, the main producer of butyrate and consequently generator of short chain fatty acids (AGCC). Likewise, Lactobacillus spp. (Homeostasis Rehabilitator). Akkermansia muciniphila (Uses mucins as an energy source). Methanobrevibacter smithii (Fermentation of polysaccharides that eliminates excess hydrogen from bacteria) and others, which, being detected decreased prior to FMT, increase after the procedure and, although briefly, lead to clinical improvement.

Due to this knowledge, I raise the question that in order to maintain the corrections given by the increase in beneficial microorganisms, FMT must be received again at least a year after the first, or once the symptoms begin to subside decline, and as a complement use biotics, paraprobiotics, postbiotics or bacteriophages.

Finally, it is necessary to consider bacterial metabolites (MB), since they are a primary factor in human health, through the development and strengthening of the intestinal immune barrier.

 Keywords: Anorexia Nervosa (AN); Fecal Microbiota Transplantation (FMT); Short Chain Fatty Acids (SCFA); Bacterial Metabolites (BM); Probiotics, Prebiotics and Symbiotics (BIOT)

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