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Clinical features and diagnosis of malabsorption

Joel B Mason, MD
Vladan Milovic, MD, PhD
Section Editor
Timothy O Lipman, MD
Deputy Editor
Shilpa Grover, MD, MPH, AGAF


Malabsorption refers to impaired absorption of nutrients [1]. It can result from congenital defects in the membrane transport systems of the small intestinal epithelium or from acquired defects in the epithelial absorptive surface. Another factor that can interfere with nutrient absorption is maldigestion, which is due to impaired digestion of nutrients within the intestinal lumen or at the terminal digestive site of the brush border membrane of mucosal epithelial cells.

Although malabsorption and maldigestion are pathophysiologically different, the processes underlying digestion and absorption are interdependent. As a result, in clinical practice the term malabsorption has come to denote derangements in both processes.

Three steps are required for normal nutrient absorption [1]:

Luminal and brush border processing

Absorption into the intestinal mucosa

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Literature review current through: Nov 2017. | This topic last updated: Jul 05, 2017.
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  1. Hogenauer C, Hammer H. Maldigestion and Malabsorption. In: Sleisenger and Fordtran's Gastrointestinal and Liver Disease, 9th ed, Feldman M, Friedman L, Brandt L (Eds), Saunders, Philadelphia, PA 2010. p.1735-1768.
  2. American Gastroenterological Association medical position statement: guidelines for the evaluation and management of chronic diarrhea. Gastroenterology 1999; 116:1461.
  3. Mustalahti K, Collin P, Sievänen H, et al. Osteopenia in patients with clinically silent coeliac disease warrants screening. Lancet 1999; 354:744.
  4. Widjaja A, Wagner S, Mix H, et al. Malabsorption with progressive weight loss and multiple intestinal ulcers in a patient with T-cell lymphoma. Z Gastroenterol 1999; 37:611.
  5. Siegel LM, Stevens PD, Lightdale CJ, et al. Combined magnification endoscopy with chromoendoscopy in the evaluation of patients with suspected malabsorption. Gastrointest Endosc 1997; 46:226.
  6. Tischendorf JJ, Wopp K, Streetz KL, et al. [The value of duodenal biopsy within routine upper endoscopy: a prospective study in 1000 patients]. Z Gastroenterol 2008; 46:771.
  7. Maglinte DD, Kelvin FM, O'Connor K, et al. Current status of small bowel radiography. Abdom Imaging 1996; 21:247.
  8. Neumeister V, Henker J, Kaltenborn G, et al. Simultaneous determination of fecal fat, nitrogen, and water by near-infrared reflectance spectroscopy. J Pediatr Gastroenterol Nutr 1997; 25:388.
  9. Fine KD, Fordtran JS. The effect of diarrhea on fecal fat excretion. Gastroenterology 1992; 102:1936.
  10. Balasekaran R, Porter JL, Santa Ana CA, Fordtran JS. Positive results on tests for steatorrhea in persons consuming olestra potato chips. Ann Intern Med 2000; 132:279.
  11. Fine KD, Ogunji F. A new method of quantitative fecal fat microscopy and its correlation with chemically measured fecal fat output. Am J Clin Pathol 2000; 113:528.
  12. Simko V. Fecal fat microscopy. Acceptable predictive value in screening for steatorrhea. Am J Gastroenterol 1981; 75:204.
  13. Khouri MR, Ng SN, Huang G, Shiau YF. Fecal triglyceride excretion is not excessive in pancreatic insufficiency. Gastroenterology 1989; 96:848.
  14. Stein J, Purschian B, Zeuzem S, et al. Quantification of fecal carbohydrates by near-infrared reflectance analysis. Clin Chem 1996; 42:309.
  15. Bekers O, Postma C, Fischer JC, et al. Faecal nitrogen determination by near-infrared spectroscopy. Eur J Clin Chem Clin Biochem 1996; 34:561.
  16. Amann ST, Josephson SA, Toskes PP. Acid steatocrit: a simple, rapid gravimetric method to determine steatorrhea. Am J Gastroenterol 1997; 92:2280.
  17. Peled Y, Doron O, Laufer H, et al. D-xylose absorption test. Urine or blood? Dig Dis Sci 1991; 36:188.
  18. Casellas F, Chicharro L, Malagelada JR. Potential usefulness of hydrogen breath test with D-xylose in clinical management of intestinal malabsorption. Dig Dis Sci 1993; 38:321.
  19. Casellas F, Malagelada JR. Clinical applicability of shortened D-xylose breath test for diagnosis of intestinal malabsorption. Dig Dis Sci 1994; 39:2320.
  20. Carlson S, Craig RM. D-xylose hydrogen breath tests compared to absorption kinetics in human patients with and without malabsorption. Dig Dis Sci 1995; 40:2259.
  21. Choi YK, Johlin FC Jr, Summers RW, et al. Fructose intolerance: an under-recognized problem. Am J Gastroenterol 2003; 98:1348.
  22. Koetse HA, Vonk RJ, Pasterkamp S, et al. Variations in colonic H2 and CO2 production as a cause of inadequate diagnosis of carbohydrate maldigestion in breath tests. Scand J Gastroenterol 2000; 35:607.
  23. Rumessen JJ, Nordgaard-Andersen I, Gudmand-Høyer E. Carbohydrate malabsorption: quantification by methane and hydrogen breath tests. Scand J Gastroenterol 1994; 29:826.
  24. Corazza GR, Benati G, Strocchi A, et al. The possible role of breath methane measurement in detecting carbohydrate malabsorption. J Lab Clin Med 1994; 124:695.
  25. Crenn P, Coudray-Lucas C, Thuillier F, et al. Postabsorptive plasma citrulline concentration is a marker of absorptive enterocyte mass and intestinal failure in humans. Gastroenterology 2000; 119:1496.
  26. Steuerwald M, Bucher HC, Müller-Brand J, et al. HIV-enteropathy and bile acid malabsorption: response to cholestyramine. Am J Gastroenterol 1995; 90:2051.
  27. Koch J, Garcia-Shelton YL, Neal EA, et al. Steatorrhea: a common manifestation in patients with HIV/AIDS. Nutrition 1996; 12:507.
  28. Oelkers P, Kirby LC, Heubi JE, Dawson PA. Primary bile acid malabsorption caused by mutations in the ileal sodium-dependent bile acid transporter gene (SLC10A2). J Clin Invest 1997; 99:1880.
  29. Popović OS, Kostić KM, Milović VB, et al. Primary bile acid malabsorption. Histologic and immunologic study in three patients. Gastroenterology 1987; 92:1851.
  30. Walters JR, Tasleem AM, Omer OS, et al. A new mechanism for bile acid diarrhea: defective feedback inhibition of bile acid biosynthesis. Clin Gastroenterol Hepatol 2009; 7:1189.
  31. Habba SF. Chronic diarrhea: identifying a new syndrome. Am J Gastroenterol 2000; 95:2140.
  32. Merrick MV. Gall-bladder and colonic retention of SeHCAT: a re-evaluation. Eur J Nucl Med 1994; 21:988.
  33. Nyhlin H, Merrick MV, Eastwood MA. Bile acid malabsorption in Crohn's disease and indications for its assessment using SeHCAT. Gut 1994; 35:90.
  34. Wildt S, Nørby Rasmussen S, Lysgård Madsen J, Rumessen JJ. Bile acid malabsorption in patients with chronic diarrhoea: clinical value of SeHCAT test. Scand J Gastroenterol 2003; 38:826.
  35. Rubio-Tapia A, Barton SH, Rosenblatt JE, Murray JA. Prevalence of small intestine bacterial overgrowth diagnosed by quantitative culture of intestinal aspirate in celiac disease. J Clin Gastroenterol 2009; 43:157.
  36. Leeds JS, Oppong K, Sanders DS. The role of fecal elastase-1 in detecting exocrine pancreatic disease. Nat Rev Gastroenterol Hepatol 2011; 8:405.