What is SIBO?

SIBO is a condition in which there is an increase in the population of the wrong kind of bacteria in your gut. This condition is also referred to as Blind loop syndrome. It’s normal and healthy to have bacteria living in your small intestine, but too many can cause problems with your digestion — especially if they’re the wrong kind. The wrong bacteria can overwhelm the beneficial bacteria that you need to be there, and they can upset your digestive system by feeding on products that aren’t meant for them.

How does SIBO occur?

Our body encompasses various mechanisms to prevent abnormal bacterial growth in our small intestine. These include:-

• Digestion by various acidic molecules and enzymes which can act on bacteria and keep the growth under check.
• Intact ileocecal valve and forward motility of the small intestine which prevent retrograde translocation of bacteria from the colon.
• Antibodies in gut in particular IgA.

Disruption in any of the above-mentioned mechanisms can lead to SIBO.

Foods that trigger SIBO- Sugar, dairy products, grains, fruit, and starchy vegetables.

Conditions causing SIBO.

• Hypochlorhydria (Low acid in the stomach)

• H Pylori infection
• Gastric Bypass Surgery
• Prolonged use of antacids and Proton pump inhibitors

• Small Intestine Motility disorders (Gut is unable to propel the food forward and that leads to a stagnant state which can lead to SIBO)

• Gastroparesis
• Hypothyroidism
• Intestinal pseudo-obstruction

• Structural abnormalities

• Abdominal adhesion
• Small bowel obstruction
• Diverticulosis

• Systemic Diseases

• Combined Variable immunodeficiency
• IgA deficiency
• HIV
• Certain medications like narcotics and antibiotics
• Celiac disease, pancreatitis

What are the Symptoms of SIBO?

• Abdominal pain
• Distension
• Constipation
• Nausea and vomiting
• Diarrhea
• Unintentional weight loss
• Fatigue
• Nutritional deficiencies

What are the tests to diagnose SIBO?

The diagnosis of SIBO is established with a positive carbohydrate breath test or duodenal aspirate culture. We perform a carbohydrate breath test to diagnose SIBO as it is simple, non-invasive, and widely available. The lactulose/glucose breath test is diagnostic of SIBO if there is an absolute increase in hydrogen by ≥20 ppm above baseline within 90 minutes bacterial concentration of >10³ colony-forming units/mL of duodenal aspirate is diagnostic of SIBO. However, the test requires an upper endoscopy to obtain an aspirate and the results are poorly reproducible.

Management of SIBO

• Antibiotics such as Rifaximin are the initial mainstay of treatment.
• Evaluation of underlying cause and its management
• Nutritional replacement

Prevention of recurrence of SIBO

• Treatment of underlying condition predisposing to SIBO
• Antibiotic prophylaxis for SIBO should be reserved for patients with ≥4 distinct and well-documented episodes within one year and risk factors for recurrent SIBO (eg, short bowel syndrome, jejunal diverticulosis). In such patients, antibiotics are administered periodically (5 to 10 days out of every month or every other week).
• FODMAP Diet
• Probiotics
• Statins