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 (fructosuria/intolerance), galactose (galactosaemia) and lactose (lactose intolerance). The reducing sugars assay typically aids initial diagnosis of an inborn error of metabolism. A positive screen for reducing substances in the faeces should be followed by sugar chromatography to identify specific carbohydrates present and provide a quantitative estimation.
Clinical Indications Neonatal/infantile presentation of generalised failure to thrive, chronic diarrhoea, hepatic dysfunction and developmental delay (often global).
Reference Range See report
Sample Required Faeces in universal container. Store frozen after receipt in lab.
Sample Volume 5 g
Transport/Storage Transport samples to laboratory immediately. Samples from outside NWLP should be sent frozen.
Turnaround Time 1 week
A positive screen for faecal reducing substances should be followed by sugar chromatography to identify specific carbohydrates present and provide a qualitative estimation.