Specimen Collection

Minimum of 24hrs faecal collection into standard container.

Specimen must not be contaminated by extraneous material.

Must specify number of days of the collect to allow calculation of faecal output in grams per day.

Reference Intervals

Reference range:

<200g/day

Diagnostic Use and Interpretation

Normal stool weight from individuals on a western diet is up to 200g/day. Pragmatically diarrhoea has been defined as abnormal passage of loose or watery stool 3 or more times per day and/or stool weight of >200g/day. However, as stool weight very much depends on amount of non-starch polysaccharide dietary fibre intake, stool weight up to 400-500g/day can occur in certain ethnic groups or populations with high dietary fiber intake. Conversely, distal colonic pathology may not increase stool weight above 200g/day. Stool weight should not be used as sole criterion for diarrhoea

Infants generally pass around 5-10g/kg/day faeces.

Other than reporting faecal weight, Labplus also reports stool consistency according to Bristol Stool Form Scale (type 1 to type 7).

References:

1. Thomas PD, Forbes A, Green J et al. Guideines for the investigation of chronic diarrhoea, 2nd edition. Gut 2003; 52(suppl V): v1-v15

2. Pomare EW, Stace NH, Fisher A. Dietary fibre intake, stool weight and intestinal transit in four south pacific populations. Aust NZ J Med 1981: 11:221(abstract)

3. Cummings JH, Bingham SA, Heaton KW et al. Fecal weight, colon cancer risk, and dietary intake of nonstarch polysaccharides (dietary fiber). Gastroenterology 1992; 103:1783-1789

4. Lewis SJ, Heaton KW. Stool form scale as a useful guide to intestinal transit time. Scand. J. Gastroenterol. 1997; 32(9): 920-4.

5. Veereman-Wauters G, Taminiau J. Chapter 9 Diarrhoea. in Pediatric Gastrointestinal and Liver disease - pathophysiology / diagnosis / management 3rd edition (2006) Wyllie R, Hyams JS (eds) Saunders Elsevier

Contact Information

Emails to chemicalpathologist@adhb.govt.nz will receive priority attention from the on-call chemical pathologist.

If the query concerns a specific patient please include the NHI number in your email.

If email is not a suitable option, please contact the on-call chemical pathologist via Lablink (Auckland City Hospital ext. 22000 or 09-3078995).

Individual chemical pathologists may be contacted but will not be available at all times.

After-hours : contact Lablink (Auckland City Hospital ext. 22000 or 09-3078995) or hospital operator for on duty staff after hours.

Dr Samarina Musaad (Clinical Lead) : SamarinaM@adhb.govt.nz ext. 22402

Dr Cam Kyle: CampbellK@adhb.govt.nz ext 22052

Dr Weldon Chiu: WeldonC@adhb.govt.nz ext. 23427

Dr Campbell Heron: CHeron@adhb.govt.nz ext. 23427

Dr Sakunthala Jayasinghe: Sakunthala@adhb.govt.nz ext. 23427

Last updated at 15:26:00 06/01/2025