Laboratory Test Reference Guide

When multiple faecal assays are required, each test must have a separate aliquot.

Steatocrit is stable for 7 days refrigerated. If sending is delayed, the sample should be frozen.

Normal <10%

Indeterminate 10 - 20%

Abnormal >20%

 In healthy patients less than 6 months old steatocrit values may be as high as 80-100% (physiological steatorrhoea) but decrease <10% when older than 6 months. A low result suggests normal fat absorption.

When investigating fat malabsorption, the Steatocrit has replaced the 72 hour faecal fat test. The 72 hour faecal fat test had several limitations, eg. adherence with diet and completeness (or lack of completeness) of the 72 hour collection and was unpopular with patients and laboratory staff.

The assay performs better when consuming 100g fat/day for 3 days prior to collection but performance of random samples is still adequate.

Suggest to collect 2 samples on separate days to allow for variation between samples.

Reference interval:

It is not possible to define a reference interval for children <6 months old. There is a large variation between samples collected on different days and levels up to 80% have been reported as being common, especially during the first month. At this age a degree of fat malabsorption is physiological. In addition, the lack of "solids" in the diet will contribute to the high Steatocrit results observed.

A limitation of the reference interval reported for patients 6 months and older is that virtually all studies have been performed in children. A paper evaluating the Steatocrit in adults suggests 75th centile is 23% and 99th centile is 30%.

Grape size sample required