Editing Malabsorption (section)

{{Short description|Abnormality in absorption of food nutrients across the gastrointestinal tract}}
{{cs1 config|name-list-style=vanc}}
{{Infobox medical condition (new)
| name          = Malabsorption
| synonyms      =
| image         = whipple2.jpg
| caption       = [[Whipple's disease]]: Alcian blue with apparently [[eosin]] counterstain enlarged [[Intestinal villus|villus]] with many [[macrophages]]
| pronounce     =
| field         = Gastroenterology
| symptoms      =
| complications = [[Malnutrition]]; [[anaemia]]; [[steatorrhoea]]; [[diarrhoea]]
| onset         =
| duration      =
| types         =
| causes        = [[Coeliac disease]]; [[short bowel syndrome]]; [[lactase deficiency]]; [[exocrine pancreatic insufficiency]]; [[small intestinal bacterial overgrowth]]; [[Whipple's disease]]; genetic diseases; certain medications<ref name="medline" />
| risks         =
| diagnosis     =
| differential  =
| prevention    =
| treatment     = Depends on cause
| medication    =
| prognosis     =
| frequency     =
| deaths        =
}}
'''Malabsorption''' is a state arising from abnormality in [[absorption (small intestine)|absorption]] of [[Nutrient|food nutrients]] across the [[gastrointestinal tract|gastrointestinal (GI) tract]]. Impairment can be of single or multiple nutrients depending on the abnormality. This may lead to [[malnutrition]] and a variety of [[anemia|anaemias]].<ref name="medline">{{Cite web|title=Malabsorption Syndrome|url=https://medlineplus.gov/malabsorptionsyndromes.html|access-date=29 April 2018|publisher=MedlinePlus|language=en}}</ref>

Normally the human gastrointestinal tract digests and absorbs dietary nutrients with remarkable efficiency. A typical Western diet ingested by an adult in one day includes approximately 100 g of fat, 400 g of carbohydrate, 100 g of protein, 2 L of fluid, and the required [[sodium]], [[potassium]], [[chloride]], [[calcium]], [[vitamins]], and other elements. {{Citation needed|date=June 2018}} [[Salivary]], [[gastric]], [[intestinal]], [[hepatic]], and [[pancreatic]] secretions add an additional 7–8 L of protein-, lipid-, and electrolyte-containing fluid to intestinal contents. This massive load is reduced by the small and large intestines to less than 200 g of stool that contains less than 8 g of fat, 1–2 g of nitrogen, and less than 20&nbsp;mmol each of {{chem2|Na+}}, {{chem2|K+}}, {{chem2|Cl-}}, {{chem2|HCO3-}}, {{chem2|Ca(2+)}}, or {{chem2|Mg(2+)}}.

If there is impairment of any of the many steps involved in the complex process of nutrient digestion and absorption, intestinal ''malabsorption'' may ensue. If the abnormality involves a single step in the absorptive process, as in primary [[lactase deficiency]], or if the disease process is limited to the very proximal small intestine, then selective malabsorption of only a single nutrient may occur. However, generalized ''malabsorption'' of multiple dietary nutrients develops when the disease process is extensive, thus disturbing several digestive and absorptive processes, as occurs in [[coeliac disease]] with extensive involvement of the [[small intestine]].<ref name="medline" />