last authored: Oct 2009, Dave LaPierre
Chronic diarrhea is defined as persistent loose, frequent stools, lasting longer than 2-3 weeks. This is in contrast to acute diarrhea. Amount is normally greater than 300g/day in adults, >200g/day in children, and >10g/kg/day in infants. Functional disorders need to persist over 3 months to make a diagnosis.
Causes of acute diarrhea can also become chronic.
Most common causes
past medical history
dietary history (4 F's)
Areas to query, with indications towards a small or large intestine cause, are as follows:
effect of fasting
Obtain body weight and height, especially in infants and children, and plot on growth chart. If child is well and thriving, little further investigations are required.
extremeties and skin
respiratory (why - CF?)
Perform a rectal examination and test for occult blood.
Given the extensive differential diagnosis, specialist referral is important if no immediate causes are identified.
Investigations should be guided by suspected diagnoses.
Low stool osmolality means people are adding water to their stool to fake symptoms.
Colonoscopy for large bowel diarrhea.
Small bowel biopsy or follow-through studies.
Emperic treatment while waiting for diagnosis includes dietary restriction, increased dietary or supplemental fibre, or cholestyramine. As cause becomes evident, treatment should be instituted accordingly.
If patients are severely malnourished, restarting nutrition can result in refeeding syndrome. Electrolytes need to be corrected and monitored as food is gradually reintroduced.
Additional supplements may be required over the short- or long-term.
This section needs to be cleaned up quite a bit..!
An osmotic diarrhea will decrease with decreased intake, while secretory diarrhea will not.
Increased transit (IBS)
maldigestion. infections can result in lactase deficiency, and people should remain on a lactose-free diet for several days to exclude this possibility.
inflammatory bowel disease
created: DLP, Aug 09
authors: DLP, Aug 09