Gastroenterology
Gastroenterology is the specialized branch of medicine that deals with the study and treatment of diseases of the stomach, intestines and the entire digestive system in general. It has particularly broad areas of expertise, as problems affecting the digestive system turn out to be increasingly numerous. Recent scientific discoveries and the use of increasingly innovative technology allow us to make more accurate diagnostic investigations and more effective treatments.
Breath Test
Lactose is the sugar found in milk: it is a disaccharide, resulting from the union of 2 simple sugars, Galactose and Glucose. Lactose is broken down into the 2 simple sugars by the enzyme lactase. Without this enzyme, Lactose cannot be broken down and thus digested. Lactose intolerance (thus Lactase deficiency) is a very common form, found in about 50% of the world’s population. About 30-40% of the Italian population is affected, although not all patients experience symptoms.
The most common symptoms of lactose intolerance are bloating, abdominal tension, cramp-like abdominal pain, meteorism, flatulence and diarrhea. Most often the symptoms, especially abdominal pain and diarrhea, appear about 1-2 hours after eating lactose-containing foods.
The H2-Breath test, or breath test, makes it possible to diagnose Lactose intolerance with certainty in a very simple way: the test is based on the oral administration of 25 grams of pure Lactose and collection of breath at regular 30-minute intervals for about 3-4 hours. During the performance of the test, the patient’s exhaled breath is examined by a special gas chromatograph that evaluates its hydrogen (H2) content from the fermentation of undigested lactose that remains in the intestinal lumen.
The Lactulose Breath Test is a simple, noninvasive and accurate test useful for diagnosing bacterial contamination of the Small Intestine (SIBO) and assessing intestinal transit time (oro-cecal).
Normally intestinal bacterial flora is localized at the colic level so it is very scarce in the small intestine where most of the food absorption processes take place. However, in some conditions (constipation, digiunal diverticula, blind loop after intestinal surgery, stagnation above phlogistic or scar stenosis, and in some cases even following irritable bowel syndromes) there may be an increase in bacterial flora in some tracts of the small intestine such that fermentation of carbohydrates in food results in nausea, bloating, meteorism, abdominal pain, weight loss, asthenia and diarrhea.
The H2-Breath test with Lactulose is the breath test to diagnose Small Intestinal Bacterial Overgrowth (SIBO). The test is based on administering 10 g of Lactulose orally and assessing, by gas chromatography, the amount of hydrogen (H2) present in the patient’s exhaled air samples and collected every 15 minutes for between 2-3 hours. The test also allows measurement of the gold-cecal transit time.
Glucose Breath Test is used to diagnose intestinal malabsorption. Glucose is normally absorbed from the small intestine, however, in the presence of bacteria, it undergoes fermentation with hydrogen production: therefore increased excretion of H2 in the exhale, it will be an indirect sign of malabsorption. Symptoms may be nausea, borborygmi, meteorism, colic-abdominal pain, weight loss, asthenia, anemia, diarrhea.
The test is based on administering 50 g of Glucose in 250 ml of water orally and evaluating, by gas chromatography, the amount of hydrogen (H2) present in the patient’s exhaled air samples collected every 15 minutes for between 2-3 hours.
Urea Breath Test
The Urea Breath Test is considered the gold standard test for the diagnosis of Helicobacter pylori a gram-negative bacterium that can infect the stomach and duodenum, which causes complaints such as epigastralgia, abdominal pain, nausea, vomiting, and can cause major diseases such as chronic gastropathy.
The test is based on the bacterium’s ability to rapidly metabolize orally administered urea to ammonia and carbon dioxide (CO2). The diagnostic urea, is marked with 13C, a non-radioactive isotope of normal Carbon; thus it can be analyzed in a special equipment (Infrared Analyzer). Helicobacter pylori, in fact, in the gastric mucosa, catabolizes marked urea and releases ammonia and CO2 marked. The latter is absorbed into the bloodstream and excreted through the lungs.
The patient, after ingesting the labeled urea, is asked to blow at set intervals into tubes that allow measurement of CO2 marked. If the bacterium is not present, the labeled urea will transit through the stomach and, since no reaction has occurred, no enrichment in CO2 marked. In contrast, in the presence of H.Pylori, the labeled urea will be broken down by bacterial urease with release of labeled CO2 that will make the breath test positive.
