lecture 4+5.pptx
- 1. CLINICAL BIOCHEMISTRY 1 Lecture No 4+5 Abnormalities of carbohydrates metabolism by Prof. Mohamed Afifi
- 2. Disaccharides Deficiencies Clinical diagnosis Cause Disease 1- inability for digestion of lactose with fermentation by intestinal bacteria. 2-Lactose Intolerance Test (Hydrogen Breath Test, Lactose Breath Test , Disaccharide Absorption ( Test, Oral Lactose Tolerance In breath test the increase of hydrogen gas is indicator. In blood test if glucose not increased with symptoms abdominal symptoms is indicator Lactase deficiency Lactase deficiency (hypolactasia or lactase nonpersistence, lac tose intolerance )
- 3. Disaccharides Deficiencies Clinical diagnosis Cause Disease 1-intestinal wall cells sucrase-isomaltase activity in the tissue samples was low in comparison to the level of enzyme activity found in a normal population 2- BREATH TESTS A- The carbon-13 breath test B-hydrogen-methane breath test 3- 4-4-4 ORAL SUCROSE CHALLENGE TEST Sucrase– Isomaltase Deficiency Sucrase– Isomaltase Deficiency) A fasting patient simply drinks a well-dissolved solution of 4 tablespoons of table sugar in a 4- ounce glass of water. If sucrase-isomaltase activity is diminished or absent, within 4 hours the patient will experience the GI symptoms associated with CSID, such as gas, bloating, abdominal distention (swelling), or diarrhea. This test is not appropriate for infants, young children, geriatric patients, and those with co-morbid conditions like diabetes. Patients may have severe symptoms if they are very sensitive to sugar. A physician should be consulted before this test is taken
- 6. Abnormalities of fructose metabolism Clinical diagnosis Cause Disease 1 increase of fructose in blood 2- Fructose in urine 3- decrease of hepatic fructokinase Lack of hepatic fructokinase Essential fructosuria 1- absence or decrease of hepatic aldolase B 2- Increase of blood sorbitol 3- fructose in urine 4- generalized aminoaciduria 5- fructose tolerance test 6-hypoglycemia 7- increase uric acid and decrease inorganic phosphate. Absence of hepatic aldolase B Hereditary fructose intolerance (HFI) Fructose-1,6- bisphosphatas e deficiency Fructose- induced hypoglycemi a
- 8. Abnormalities of galactose metabolism Clinical diagnosis Cause Disease 1 increase of galactose in blood 2- galactose in urine 3-Galactitol and galactonic acid in blood and urine 4- deficiency of glactokinase I RBCs Galactokinase deficiency Galactokinase defeciency 1 increase of galactose in blood 2- galactose in urine 3-Galactitol and galactonic acid in blood and urine 4- deficiency of Glactose-1- phosphate uridyl transferase RBCs 5- Generalized aminoaciduria and proteinuria . Glactose-1- phosphate uridyl transferase deficiency Galactosemia
- 9. 1- red cell galactose-1- phosphate is increased 2- GALT is normal 3-Epimerase in erythrocytes is low or absent 4- GALE gene sequencing Uridine diphosphate- galactose 4′- Epimerase deficiency Uridine diphosphat e-galactose 4′- Epimerase deficiency (GALE )
- 10. DISORDERS OF PENTOSE METABOLISM Clinical diagnosis Cause Disease Decrease the activity of RBCs G6PDH Glucose 6 phosphate deficiency Favism 1- decrease of transaldolase Activity in fibroblasts, lymphoblasts, or liver tissue. 2-Elevated urine erythritol, arabitol, ribitol, sedoheptitol, perseitol, sedoheptulose, mannoheptulose, and sedoheptulose-7P 3- Sequencing of transaldolase gene. . Transaldolase Deficiency Transaldolase Deficiency fibroblast homogenates showed deficient activity in ribose-5-phosphate isomerase. Ribose-5- Phosphate Isomerase Deficiency Ribose-5- Phosphate Isomerase Deficiency The urine contains l-xylulose, which is excreted in increased amounts (1–4 g daily xylitol dehydrogenase deficiency Essential Pentosuria
- 11. Abnormalities of glucose metabolism 1- Hyperglycemia 2- DM 3-hypoglycemia 4- Glucosuria In text book from page 56-64