28
May
Faeces for reducing substances test must be frozen at collection. Faecal reducing substances is used for the investigation of carbohydrate malabsoption in primary disaccharidase deficiency secondary to immature Gi tract or intestinal disease.
In infants measurable faecal reducing substances are due to carbohydrate metabolism.
Faecal reducing substances test. Sugars eg glucose galactose fructose maltose lactose and pentose are characterized as reducing substances based on their ability to reduce cupric ions to cuprous ions. Faecal reducing substances have previously been requested when carbohydrate malabsorption is suspected in a child eg. Evidence of diarrhoea or intestinal hurry not explained by other causes and to investigate for disaccharidase.
Test background Faecal reducing sugars in infants reflect a process of intestinal hurry or diarrhoea secondary to other causes that prevent complete absorption in the intestines. The main substances likely to be detected in the faeces of infants include. Glucose fructose fructosuriaintolerance galactose galactosaemia and lactose lactose intolerance.
Please note this test is only available for children 4years RCH suggest a Hydrogen Breath Test to investigate for malabsorption of sugars. Diagnosis of sugar intolerancelactose sucrose or glucosegalactose. Although the test is usually done with faecal pH measurement the latter does not provide any additional useful diagnostic information.
A positive result indicates reduced digestion or. This test is no longer available for Patients greater than 4 years of age Hydrogen breath testing is now the recommended procedureFor children less than 4 years faecal reducing substances is still offered but breath testing at RCH should be considered. Faeces for reducing substances test must be frozen at collection.
Faecal reducing substances using the now obsolete Clinitest tablet method were in use but results were uninterpretable. Positive results are seen in normals and negative results in patients with disaccharidase deficiency. Often dietary restriction of lactose is necessary as an empirical test or alternatively the hydrogen breath test may be.
Faecal reducing substances From 1st November 2012 this test will no longer be offered. This is due to a combination of ongoing supply problems and questionable clinical value. Unfortunately the test suffers from significant sensitivity and specificity issues resulting in more and more laboratories discontinuing the test.
The stool-reducing substances test is used to detect the presence of such unabsorbed sugar in your stools. Fructose glucose lactose pentose and galactose are some reducing sugars that can be identified in a stool sample with this test. The results of this test will be sent to your doctor who requested the test at your childs Out-patients appointment approximately two weeks after the sample has arrived in the laboratory.
If you have any queries please telephone 0161 701 2255 Paediatric Duty Biochemist. The Laboratory is open Monday-Friday 900 am to 500 pm. Testing for reducing substances in the stools is not always helpful.
Infants with positive reducing substances may have sufficient lactase activity because lactase breaks down lactose into glucose and galactose the presence of 20-25 milligrams per deciliter of glucose above fasting levels indicates sufficient levels of lactase. The recommended alternative testing strategies are as follows. Historically requested to screen faeces for the presence of lactose to support a diagnosis of lactose intolerance as a cause of osmotic diarrhoea.
Trialling a lactose free diet and monitoring symptoms is recommended. Reducing substances urine And faecal The presence of sugar in the urine mellituria may be the result of either physiological or pathological conditions affecting absorption metabolism or renal function. Detection of sugar in faeces is due to malabsorption this can be due to a number of reasons such as diarrhoea or disaccharide intolerance.
This test is no longer available for Patients greater than 4 years of age Hydrogen breath testing is now the recommended procedureFor children less than 4 years faecal reducing substances is still offered but breath testing at RCH should be considered. Some drugs cause a falsepositive reducing substances test include salicylate penicillin ascorbic acid nalidixic acid cephalosporins and probenecid. Clinical decision points.
Food leaving the stomach first enters the small bowel. Reducing substances are monosaccharide by-products of carbohydrate metabolism. Fresh stool samples are required and assays should be performed immediately.
In infants measurable faecal reducing substances are due to carbohydrate metabolism. But the test cannot differentiate lactose from fructose glucose and galactose malabsorption so specificity is quite low. Stool test for Faecal Reducing Substances.
The unabsorbed lactose ferments and makes the loose stools acidic and traces of lactose can be measured in the diarrhoea confirming lactose intolerance. Lomer MCE Parkes GC Sanderson JD. Lactose intolerance in clinical practicemyths and realities.
For many years faecal reducing substances was the only screening test available for the investigation of suspected lactose intolerance yet results from this inherently insensitive non-specific assay were often unhelpful. The hydrogen breath test and disaccharidase assay provide greatly superior diagnostic information but their expense. If a Reducing Substances test has been requested by your doctor as well a second faeces container is required as a portion of faeces must be kept frozen until delivery.
Collecting a childs faeces. Step 1 Obtain a faeces collection container from your. Faecal reducing substances is used for the investigation of carbohydrate malabsoption in primary disaccharidase deficiency secondary to immature Gi tract or intestinal disease.
Request a test To request this test please send sample with a request providing patient ID three identifiers specimen information assay required relevant clinical details and sender information. Helicobacter pylori breath test Faecal reducing substances Faecal elastase Faecal calprotectin Lactose Tolerance Test blood Lactose tolerance test breath Fructose tolerance test breath Markers of Heart Disease Troponin I myocardial infarction ischaemia BNP heart failure Miscellaneous Porphyrins. Faeces specimen collected in sterile brown or white container.
The sample can be passed into a separate clean container or firstly onto paper in the toilet bowl and then scraped into the sterile brown top specimen container using the scoop which forms part of the lid. Write your surname first given name date of birth and date and. The Faeces Reducing Substances test orderable in eMR will be discontinued from Monday 14th August 2017 and replaced with the test orderable Faecal Sugars and the synonym Faecal Carbohydrates.
From this date specimens for faecal sugars will be sent to the Biochemistry Department at The Childrens Hospital at Westmead which is a Centre of Excellence for screening and identification of faecal sugars. Small bowel disaccharidase testing. Remains a very good test for lactose intolerance but is an invasive test that requires small bowel biopsy.
Cannot differentiate between primary and secondary lactase deficiency. Lactose tolerance test.