Which of the following is not used for investigation of fat malabsorption
Ans. is 'd' i.e., 13C triclosan [Pediatric Drug Development Concepts and Applications (John Wiley & Sons, 2011)/81; 1 3C-Breath Tests in Medical Research and Clinical Diagnosis ( 13c-breathtests.pdfl Triclosan is not used for the evaluation of fat malabsorption. Triclosan is an antibacterial and antifungal agent found in mumerous consumer products, including soaps, detergents, toys and surgical cleaning treatments. Its efficacy as an antimicrobial agent and the risk of antibacterial rasistance ramains controversial. Tests used for fat malabsorption Triolene breath test 13C triolene breath test is a simple and reproducible method to measure fat malabsorption. o It is a non invasive test and it does not require the use of radioactive isotopes. The 14C triolene breath test is sensitive and specific for measuring fat malabsorption but involve radiation exposure. 13C triolene is simple and effective that does not involve the use of radioactive isotopes. The substrate for this breath test is glycerol, esterified in three positions with the unsaturated 18:1 n-1 oleic acid. The absorption of triolene is dependent on efficient lipolysis, sufficient intraluminal bile salt concentration and intact intestinal mucosa. A low 13C breath excretion represents probable contribution of all these factors. The Tripalmitin breath test :? The substrate is glycerol esterified with 16:0 fatty acid palmitic acid. The oxidation of CO2 is determined by hydrolysis, bile salt concentration and absorption through intestine. C Mixed-Triglyceride Breath Test The "C mixed-triglyceride (MTG) breath test is a noninvasive test with which to measure lipase activity. The test molecule, 1,3 distearyl, 2 (carboxyl-"C) octanoyl glycerol, consists of a medium-chain fatty acid octanoic acid marked with "C in the 2-position and the long-chain fatty acid 18:0 in the 1- and 3-position. The rationale of the test is that the two stearyl groups have to be split off the glycerol by lipase before "C octanoyl monoglyceride or 13C octanoate, a medium-chain fatty acid, is absorbed and rapidly metabolized to "CO2, which appears in breath. The rate-limiting step in the oxidation of '3CO2is the hydrolysis of the fatty acids in the 1- and 3-positions of the mixed triglyceride. The amount of '3CO2 that appears in breath is an indicator of lipase activity. After an overnight fast, two basal breath samples are taken. The test meal, a slice of white bread with chocolate paste (containing 250 mg 13C MTG), is ingested. After the meal, breath samples are collected at 30-min intervals for a period of 6h. LIC-Trioctanoin Breath Test The substrate for the trioctanoin breath test is glycerol, esterified with the 8:0 medium-chain fatty acid, octanoic acid. Because the absorption of MCT is independent of bile salts and occurs immediately after hydrolysis by pancreatic lipase, absorption can be limited only by insufficient lipolysis. This test allows discrimination between patients with pancreatic insufficiency and patients with bile acid deficiency or mucosal abnormalities.
13C Trioctanoin
13C Triolein
13C Tripalmitin
13C Triclosan