Small intestinal fungal overgrowth (SIFO) is characterized by the presence of excessive number of fungal organisms in the small intestine associated with gastrointestinal (GI) symptoms. Candidiasis is known to cause GI symptoms particularly in immunocompromised patients or those receiving steroids or antibiotics. However, only recently, there is emerging literature that an overgrowth of fungus in the small intestine of non-immunocompromised subjects may cause unexplained GI symptoms. Two recent studies showed that 26 % (24/94) and 25.3 % (38/150) of a series of patients with unexplained GI symptoms had SIFO. The most common symptoms observed in these patients were belching, bloating, indigestion, nausea, diarrhea, and gas. The underlying mechanism(s) that predisposes to SIFO is unclear but small intestinal dysmotility and use of proton pump inhibitors has been implicated. However, further studies are needed; both to confirm these observations and to examine the clinical relevance of fungal overgrowth, both in healthy subjects and in patients with otherwise unexplained GI symptoms. Importantly, whether eradication or its treatment leads to resolution of symptoms remains unclear; at present, a 2–3-week course of antifungal therapy is recommended and may be effective in improving symptoms, but evidence for eradication is lacking.
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We acknowledge the technical and secretarial assistance of Ms. Helen Smith.
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Askin Erdogan and Satish S.C. Rao declare that they have no conflict of interest.
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This article does not contain any studies with human or animal subjects performed by any of the authors. Among cited articles where one of the authors of the current report were authors, local Institutional Review Board approval was obtained and maintained for studies where human (or animal) subjects research was performed.
This article is part of the Topical Collection on Neurogastroenterology and Motility Disorders of the Gastrointestinal Tract
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Erdogan, A., Rao, S.S.C. Small Intestinal Fungal Overgrowth. Curr Gastroenterol Rep 17, 16 (2015). https://doi.org/10.1007/s11894-015-0436-2
- Small intestine
- Fungal overgrowth
- Duodenal culture