Small intestinal bacterial overgrowth mimicking acute flare as a pitfall in patients with Crohn's Disease

Abstract

BackgroundSmall intestinal bacterial overgrowth (SIBO) is characterized by excessive proliferation of colonic bacterial species in the small bowel. Potential causes of SIBO include fistulae, strictures or motility disturbances. Hence, patients with Crohn's Disease (CD) are especially predisposed to develop SIBO. As result, CD patients may experience malabsorption and report symptoms such as weight loss, watery diarrhea, meteorism, flatulence and abdominal pain, mimicking acute flare in these patients.MethodsOne-hundred-fifty patients with CD reporting increased stool frequency, meteorism and/or abdominal pain were prospectively evaluated for SIBO with the Hydrogen Glucose Breath Test (HGBT).ResultsThirty-eight patients (25.3%) were diagnosed with SIBO based on positive findings at HGBT. SIBO patients reported a higher rate of abdominal complaints and exhibited increased stool frequency (5.9 vs. 3.7 bowel movements/day, p = 0.003) and lower body weight (63.6 vs 70.4 kg, p = 0.014). There was no correlation with the Crohn's Disease Activity Index. SIBO was significantly more frequent in patients with partial resection of the colon or multiple intestinal surgeries; there was also a clear trend in patients with ileocecal resection that did not reach statistical significance. SIBO rate was also higher in patients with affection of both the colon and small bowel, while inflammation of the (neo)terminal ileum again showed only tendential association with the development of SIBO.ConclusionSIBO represents a frequently ignored yet clinically relevant complication in CD, often mimicking acute flare. Because symptoms of SIBO are often difficult to differentiate from those caused by the underlying disease, targeted work-up is recommended in patients with corresponding clinical signs and predisposing factors.

Small Intestinal Bacterial Overgrowth following Subtotal Colectomy for Colon Cancer

“…One, the ileo-cecal valve serves as an important barrier between the ileum and cecum that not only regulates flow of contents from the small bowel to the cecum but also prevents reflux of contents and transmigration of colonic contents and bacteria into the small bowel. Loss of ileocecal valve is a known risk factor for the development of SIBO [10,11]. And second is that subtotal colectomy alters the natural anatomy together with postoperative changes such as adhesions may lead to altered gut motility resulting in increased risk of SIBO.…”

Post-operative recurrence in Crohn's disease. Critical analysis of potential risk factors. An update

“…Hence, patients with CD are especially predisposed to develop SIBO. 57 Rana et al have pointed out that the occurrence of SIBO was significantly higher in CD patients (45.2%) as compared to controls (0.86%) and UC patients (17.8%). 58 Also Castiglione et al, in their study, have found a higher percentage of SIBO in CD patients.…”

“…In their studies Klaus et al and Castiglione et al have shown that the prevalence of SIBO is higher in patients with prior ileocecal resection than in those who have not undergone prior surgery or multiple respective procedures. 57,59 One reason might be a change, especially a reduction in motility in the bowel following surgery. This may be reflected in data reported by Castiglione et al, who found a prolongation of oro-cecal transit time in patients with CD compared to healthy controls.…”

“…59 In a prospective study analyzing the prevalence, predisposing factors and clinical relevance of SIBO in patients with CD the authors found that fully a quarter of all patients (38/150, 25.3%) with CD and abdominal complaints suffer from SIBO. 57 In addition, an intact ileocecal valve serves as a physiological barrier between the small bowel and colon. For this reason surgical procedures involving the gastrointestinal tract, especially ileocecal resection, are considered by many authors as a potential risk factor as well as strictures or fistulae.…”

Small Intestinal Bacterial Overgrowth

“…Likewise, stricture formation with chronic dilatation is usually associated with overgrowth. This may be seen in Crohn's disease, radiation enteritis, or children with congenital anomalies such as intestinal atresia who have postoperative strictures with some degree of dysmotility [30,31].…”