Stool Reducing Substances
Private Stool Reducing Substances testing in London for £74.99, assessing one carbohydrate malabsorption marker with results in around 2–3 weeks.
Turnaround time
2-3 weeks
Biomarkers count
1
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Overview of the Stool Reducing Substances Test
The Stool Reducing Substances test detects reducing sugars within a stool sample, providing laboratory information that can support investigation of carbohydrate malabsorption.
The test assesses 1 specialist gastrointestinal marker: Stool Reducing Substances.
Carbohydrates normally need to be digested into absorbable sugars before they can be taken up through the small intestine.
If carbohydrate digestion or absorption is impaired, greater quantities of sugar can remain within the intestinal contents and pass into stool.
Several sugars can act as reducing substances, including glucose, galactose, fructose and lactose-derived sugars.
The test does not identify one specific sugar or diagnose one particular digestive disorder.
Historically, stool reducing substances have been used particularly in infants and young children with persistent diarrhoea where carbohydrate malabsorption is being considered.
One possible cause is lactose malabsorption.
Other enzyme deficiencies, intestinal mucosal disease and congenital carbohydrate disorders can also produce abnormal findings.
The test has important limitations.
Bacteria within the bowel can metabolise sugars before the sample is analysed, potentially reducing the amount detected.
Specimen storage and transport are therefore important.
Current specialist laboratory instructions state that the stool specimen should be separated and frozen if being sent overnight.
The result should also be interpreted with stool pH, symptoms, diet and other gastrointestinal investigations where relevant.
Modern breath testing, enzyme studies, genetic testing and other specialist investigations may provide more specific information depending on the suspected disorder.
A positive Stool Reducing Substances result therefore supports carbohydrate malabsorption but does not identify its exact cause.
What Does the Stool Reducing Substances Test Check?
The test detects reducing sugars within stool that can accumulate when dietary carbohydrates are not fully digested or absorbed. This test measures 1 specialist biomarker.
Stool Reducing Substances
Detects reducing sugars in stool, supporting investigation of carbohydrate malabsorption, particularly in infants and children with persistent diarrhoea.
Who May Benefit From the Stool Reducing Substances Test?
Stool Reducing Substances testing is mainly used where carbohydrate malabsorption is being investigated, particularly in paediatric gastrointestinal assessment.
Infants with persistent watery or acidic diarrhoea - Unabsorbed carbohydrate can draw water into the intestine and contribute to diarrhoea.
Children with suspected carbohydrate malabsorption - Stool testing can provide preliminary evidence of unabsorbed reducing sugars.
People with suspected lactose malabsorption where specialist stool testing has been requested - Undigested lactose-related sugars can contribute to a positive result.
Children with poor weight gain and persistent diarrhoea - Malabsorption is one possible mechanism requiring further assessment.
People with symptoms after particular carbohydrate-containing foods - Additional investigation may help identify whether carbohydrate digestion is impaired.
People with gastrointestinal disease affecting the small-intestinal lining - Mucosal injury can reduce carbohydrate absorption.
People with a previous positive reducing-substances result - Further testing can help identify the underlying cause.
People specifically referred for paediatric or specialist malabsorption investigation - Interpretation is strongest when the test answers a defined clinical question.
How to Prepare
Correct specimen handling is important because bacteria can continue to metabolise sugars after the sample is passed.
Poor storage can therefore reduce the reliability of the result.
Symptoms and Reasons to Consider the Stool Reducing Substances Test
Carbohydrate malabsorption can alter stool consistency and produce gastrointestinal symptoms after carbohydrate ingestion.
Persistent watery diarrhoea - Unabsorbed carbohydrates can increase osmotic water retention within the bowel.
Loose stools after milk or carbohydrate-containing feeds - Specific sugar malabsorption can produce diet-related symptoms.
Abdominal bloating - Colonic fermentation of unabsorbed carbohydrate can generate gas.
Excessive flatulence - Bacterial metabolism of sugars can increase gas production.
Abdominal discomfort after carbohydrate intake - Malabsorption can produce cramping or discomfort.
Poor weight gain in a child with chronic diarrhoea - Significant malabsorption can affect nutritional status.
Persistent diarrhoea following intestinal infection - Temporary lactase deficiency can occasionally follow gastrointestinal illness.
Stool Reducing Substances is a screening marker rather than a diagnosis of lactose intolerance or another specific carbohydrate disorder.
Persistent diarrhoea, dehydration, blood in stool, significant weight loss or poor growth requires appropriate paediatric or gastroenterological assessment.
How to Book Your Stool Reducing Substances Test
The Stool Reducing Substances test can be booked privately for specialist investigation of carbohydrate malabsorption.
Choose the Stool Reducing Substances
Select the individual stool test online.
Select your sample collection option
Obtain the appropriate stool specimen container and laboratory collection instructions.
Collect your sample
Provide a fresh stool specimen according to the instructions and avoid contamination.
Laboratory analysis
Your stool specimen undergoes testing for Stool Reducing Substances.
Receive your results securely
Your authorised result is delivered securely and can be interpreted alongside symptoms, diet and other gastrointestinal investigations.
When Will I Receive My Results?
The current specialist laboratory turnaround for Stool Reducing Substances is approximately 2–3 weeks after laboratory receipt.
This is a specialist microbiology and gastrointestinal investigation rather than a routine stool test.
The specimen requires appropriate processing and analysis before laboratory authorisation.
Correct storage is particularly important because the laboratory advises freezing where the specimen is being sent overnight.
Understanding Your Results
A negative result means significant reducing sugars were not detected within the stool specimen under the assay conditions.
This makes substantial carbohydrate malabsorption less likely but does not exclude every digestive enzyme or absorption disorder.
A positive result indicates that reducing substances are present.
This can support carbohydrate malabsorption but does not establish which specific carbohydrate is responsible.
Lactose malabsorption is one possibility.
Fructose, glucose, galactose and other reducing sugars can also contribute.
The result is particularly dependent on specimen handling.
Bacterial metabolism after stool collection can reduce detectable sugars and potentially produce a falsely reassuring result.
Further investigation can include dietary assessment, breath testing, specialist enzyme or genetic studies, depending on the suspected cause and the patient's age.
Why Book With London Blood Tests?
London Blood Tests provides private access to specialist Stool Reducing Substances testing for carbohydrate malabsorption assessment.
Detects unabsorbed reducing sugars - The test provides laboratory evidence relevant to carbohydrate digestion and absorption.
Useful in paediatric diarrhoea assessment - It has a particular role in infants and children with persistent diarrhoea.
Relevant to suspected carbohydrate malabsorption - A positive result can support further investigation.
Non-invasive stool testing - No blood sample is required.
Can guide more specific investigations - Further testing can target lactose or other carbohydrate disorders.
Specialist laboratory processing - Specimen handling and storage requirements are followed carefully.
Suitable for clinician-directed gastrointestinal assessment - Results can be interpreted alongside diet and symptoms.
Clear pricing - The Stool Reducing Substances test costs £74.99.
Private Stool Reducing Substances Test in London
London Blood Tests provides private Stool Reducing Substances testing for people requiring investigation of carbohydrate malabsorption.
The test costs £74.99 and assesses 1 specialist stool marker.
Results are expected approximately 2–3 weeks after laboratory receipt.
Correct specimen handling is essential because continued bacterial metabolism can affect the amount of reducing sugar detected.