Bacterial overgrowth syndromes

Toskes PP, Donaldson RM Enteric bacterial flora and bacterial overgrowth syndrome in Sleisenger MH, Fordtran JS (eds) Gastrointestinal Disease. Philadelphia, Saunders, 1993, pp 1106-1125. 

Bouhnik Y, Alain S, Attar A, Flourie B, Ras-kine L, Sanson-Le Pors MJ, Rambaud JC Bacterial populations contaminating the upper gut in patients with small intestinal bacterial overgrowth syndrome. Am J Gastroenterol 1999 94 1327-1331. 

Rifaximin is available in Europe for the treatment of acute intestinal bacterial infections, hepatic encephalopathy, bacterial overgrowth syndrome, diverticular disease of the colon, and for the prevention of infections after colorectal surgery [3, 4]. Rifaximin is also licensed in Mexico, Asia and Northern Africa and has recently been approved in USA for the treatment of traveler s diarrhea. 

As outlined in the excellent review by Gilles and Brogden [9], the current indications for rifaximin include surgical prophylaxis and the treatment of hepatic encephalopathy, infectious diarrhea and intestinal bacterial overgrowth syndromes. As such, rifaximin is aimed only at enteric flora. Owing to its lack of absorption, rifaximin will likely not be used for other conditions or indications. Such limited indications should help preserve the activity of the agent, since overuse for common conditions like urinary or respiratory tract infections will naturally not occur. Limited use should help retard the development of resistance among enteric flora. 

Banwell JG, Kistel LA, Giannella RA, Weber FL, Lieber A, Powell DE Small intestine bacterial overgrowth syndrome. Gastroenterology 1981 80 834-845. 

Bacterial overgrowth syndromes in various diseases (diabetes, scleroderma, jejunal diverticulosis, blind loops)... 

Bacterial overgrowth Pathogenesis Gastrointestinal motility Gastric acid Malabsorption syndromes... 

Connective Tissue Diseases. Scleroderma is the connective tissue disease most frequently associated with intestinal dysmotility and bacterial overgrowth [159, 160]. Although the motility of the esophagus is most frequently affected, and a prerequisite for the label CREST syndrome, small bowel involvement is seen in a proportion of these patients. When present, intestinal clearance is usually impaired because of shallow contractions resulting in ineffective peristalsis and clearance. This can lead to overgrowth with Gram-negative bacilli, in part responsible for the malabsorption [161]. 

Shindo K, Machida M, Miyakawa K, Fukumura M A syndrome of cirrhosis, achlorhydria, small intestinal bacterial overgrowth, and fat malabsorption. Am J Gastroenterol 1993 88 2084-2091. 

Pignata C, Budillon G, Monaco G, Nani E, Cuomo R, Pamilli G, et al Jejunal bacterial overgrowth and intestinal permeability in children with immunodeficiency syndromes. Gut 1990 31 879-882. 

Lin HC Small intestinal bacterial overgrowth A framework for understanding irritable bowel syndrome. JAMA 2004 292 852-858. 

Rifaximin Rifamycin Antibiotic Gut bacteria Enteric infection Diarrhea, infectious Hepatic encephalopathy Small intestine bacterial overgrowth Inflammatory bowel disease Colonic diverticular disease Irritable bowel syndrome Constipation Clostridium difficile infection Helicobacter pylori infection Colorectal surgery Bowel decontamination, selective Pancreatitis, acute Bacterial peritonitis, spontaneous Nonsteroidal anti-inflammatory drug enteropathy... 

Di Stefano M, Pezzimenti D, Veneto G, Missa-nelli A, Corazza GR Absorbable vs. nonabsorbable antibiotics in the therapy of small intestine bacterial overgrowth (SIBO) in patients with blind loop syndrome. Dig Liver Dis 2001 33 A93. 

Pimentel H, Chow EJ, Lin HC. Eradication of small intestinal bacterial overgrowth reduces symptoms of irritable bowel syndrome. Am J Gastroenterol 2000 95 3503-3506. 

Vitamin 8 2 deficiency Vitamin B-12 deficiency due to malabsorption syndrome as seen in pernicious anemia Gl pathology, dysfunction or surgery fish tapeworm infestation malignancy of pancreas or bowel gluten enteropathy sprue small bowel bacterial overgrowth total or partial gastrectomy accompanying folic acid deficiency. Increased vitamin B-12 requirements Increased vitamin B-12 requirements associated... 

Octreotide inhibits intestinal secretion and has dose-related effects on bowel motility. In low doses (50 meg subcutaneously), it stimulates motility, whereas at higher doses (eg, 100-250 meg subcutaneously), it inhibits motility. Octreotide is effective in higher doses for the treatment of diarrhea due to vagotomy or dumping syndrome as well as for diarrhea caused by short bowel syndrome or AIDS. Octreotide has been used in low doses (50 meg subcutaneously) to stimulate small bowel motility in patients with small bowel bacterial overgrowth or intestinal pseudo-obstruction secondary to scleroderma. 

Abdominal surgery, radiation therapy Loss of absorptive surface Bypass Nutrient unavailability, deconjugation of bile acids Disturbed solubilization of lipids, decreased formation of micelles Short-bowel syndrome Enteroenteric fistual Bacterial overgrowth Loss of bile acids... 

Improper milieu Abnormal motility secondary to diabetes, scleroderma, hyperthyroidism Bacterial overgrowth - blind loops (deconjugation of bile salts), diverticula Zollinger-Ellison syndrome (low duodenal pH)... 

Biliary obstruction due to stone, tumor, or primary biliary cirrhosis Zollinger-Ellison syndrome (causes hyperacidity) bacterial overgrowth and stasis administration of drugs, neomycin, and cholestyramine Ileal disease or resection... 

Patients have been described who have a vitamin Bi2 deficiency that is not correctable by IF. In the Schilling test with or without added IF, these patients have a low urinary output of radioactivity. This finding could be due to a deficiency or defect in the ileal receptor protein. More commonly, it occurs when there is an acquired ileal defect such as a bacterial overgrowth (blind loop syndrome) or tropical sprue. 

Vanderhoof JA, et al. Treatment strategies for small bowel bacterial overgrowth in short bowel syndrome. J Pediatr Gastroenterol Nutr 1998 27 155-160. 

Deconjugation of bile acids may become excessive when bacterial overgrowth occurs in the small intestine. This condition is referred to as the stagnant loop or blind loop syndrome and is characterized by diarrhea, often accompanied by steatorrhea because of a decrease in the effective concentration of conjugated bile salts and a reduction in the fat-absorptive capacity of the small intestine. 

A comparison between two commercial delayed release peppermint oil preparations found that there were differences in the pharmacokinetics in relation to bioavailability times and release site. A capsule that is more effective in delivering the peppermint oil to the distal small intestine and ascending colon would be more bene cial in the treatment of irritable bowel syndrome (White et al., 1987). It has also been suggested that the con icting results in some trials may be due to the inclusion of patients suffering from lactose intolerance, syndrome of small intestinal bacterial overgrowth, and celiac disease, all of which have symptoms similar to irritable bowel disease (Cappello et al., 2007). 

It has been speculated that bacterial overgrowth in the jejunum during acid inhibition may produce malabsorption, similar to the blind-loop syndrome. However, despite elevated concentrations of colonic-type bacteria in the duodenum during omeprazole therapy [48,49, 58], malabsorption of fat and carbohydrates could not be demonstrated [48, 58]. Also, serum con-... 

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