//fpnotebook.com/
Chronic Diarrhea
Aka: Chronic Diarrhea
- See Also
- Acute Diarrhea
- Diarrhea in Cancer
- Diarrhea in Children
- Diarrhea in Pregnancy
- Diarrhea in HIV
- Definitions
- Chronic Diarrhea
- Persistent Diarrhea with decreased stool consistency >4 weeks
- Epidemiology
- Prevalence: 1-5% of adults
- Causes: Common
- Irritable Bowel Syndrome
- Inflammatory Bowel Disease
- Celiac Disease
- Microscopic Colitis
- Causes: By Type
- Chronic Fatty Diarrhea
- Diarrhea due to Malabsorption
- Chronic Inflammatory Diarrhea
- Infectious Diarrhea
- Inflammatory Bowel Disease
- Chronic Watery Diarrhea
- Secretory Diarrhea
- Large volume stools >1 L/day and not better over night or with Fasting
- Osmotic Diarrhea
- Drug-Induced Diarrhea
- Functional Chronic Diarrhea (diagnosis of exclusion)
- Small volume stools (<350 ml/day and better over night and with Fasting)
- Irritable Bowel Syndrome
- History
- Stool characteristics
- Water: Chronic Watery Diarrhea
- Blood, pus or mucus: Chronic Inflammatory Diarrhea
- Foul, bulky, greasy stools: Chronic Fatty Diarrhea
- Age
- Young patients
- Inflammatory Bowel Disease
- Tuberculosis
- Functional bowel disorder (Irritable Bowel Syndrome)
- Older patients
- Colon Cancer
- Diverticulitis
- Diarrhea pattern
- Diarrhea alternates with Constipation
- Colon Cancer
- Laxative abuse
- Diverticulitis
- Functional bowel disorder (Irritable Bowel Syndrome)
- Intermittent Diarrhea
- Diverticulitis
- Functional bowel disorder (Irritable Bowel Syndrome)
- Malabsorption
- Persistent Diarrhea
- Inflammatory Bowel Disease
- Laxative abuse
- Differentiating Small Bowel from Large Bowel
- Small Intestine or proximal colon involved
- Large stool Diarrhea
- Abdominal cramping persists after Defecation
- Distal colon involved
- Small stool Diarrhea
- Abdominal cramping relieved by Defecation
- Diurnal variation
- No relationship to time of day: Infectious Diarrhea
- Morning Diarrhea and after meals
- Gastric cause
- Functional bowel disorder (e.g. Irritable Bowel Syndrome)
- Inflammatory Bowel Disease
- Nocturnal Diarrhea (always organic)
- Diabetic Neuropathy
- Inflammatory Bowel Disease
- Weight Loss
- Despite normal appetite
- Hyperthyroidism
- Malabsorption (e.g. Celiac Sprue)
- Giardia
- Cryptosporidium
- Cyclospora
- Associated with fever
- Inflammatory Bowel Disease
- Weight loss prior to Diarrhea onset
- Pancreatic Cancer
- Tuberculosis
- Diabetes Mellitus
- Hyperthyroidism
- Malabsorption
- Medication and dietary intakes
- See Drug-Induced Diarrhea
- See Foodborne Illness
- See Waterborne Illness
- High fructose corn syrup
- Excessive Sorbitol, Mannitol (chewing gum)
- Artificial Sweeteners (e.g. Sucralose, chewing gum, fruit juice, soft drinks)
- Excessive coffee or other Caffeine
- Alcohol Abuse
- Illicit Drug use
- Recent travel to undeveloped areas
- See Traveler's Diarrhea
- See Infectious Diarrhea
- Red Flags: Suggestive of organic cause
- Painless Diarrhea
- Recent onset in an older patient
- Nocturnal Diarrhea (especially if wakes patient)
- Unintentional Weight Loss
- Blood in stool
- Large stool volumes: >400 grams stool per day
- Anemia
- Hypoalbuminemia
- Erythrocyte Sedimentation Rate increased
- Signs
- Vital Signs
- Weight loss (red flag - see causes above)
- Eye Exam
- Episcleritis (Inflammatory Bowel Disease)
- Neck Exam
- Lymphadenopathy
- Thyromegaly (Hyperthyroidism)
- Abdominal exam
- Surgical scars
- Hypermotility
- Hepatomegaly
- Abdominal Tenderness
- Abdominal mass
- Rectal exam
- Anal Fistula (Crohn Disease)
- Rectal exam (Stool impaction - pseudo-Diarrhea)
- Fecal Occult Blood Testing
- Skin exam
- Dermatitis Herpetiformis (Celiac Sprue)
- Labs: First-line
- Complete Blood Count
- Thyroid Stimulating Hormone (TSH)
- Serum Electrolytes
- Liver Function Tests
- C-Reactive Protein
- Celiac Sprue testing (esp. if signs of Iron Deficiency)
- IgA Tissue Transglutaminase and
- Total IgA (with reflex if low to IgG Gliadin)
- Labs: Stool evaluation
- First-Line Tests
- Stool Ova and Parasite (2-3 samples)
- Giardia lambliaAntigen
- Indicated for Diarrhea >7 days and >10 stools/day
- Clostridium difficile Toxin
- Indicated if recent antibiotics or hospitalization
- Fecal fat with sudan stain (abnormal if >14 grams/24 hours)
- See Chronic Fatty Diarrhea (Malabsorption)
- Fecal lactoferrin or Fecal Calprotectin
- See Chronic Inflammatory Diarrhea (e.g. Infectious Diarrhea, Inflammatory Bowel Disease)
- Fecal Calprotectin <40 mcg/g and CRP <0.5 reduce Inflammatory Bowel Disease likelihood to<1%
- Menees (2015) Am J Gastroenterol 110(3):444-54 [PubMed]
- Fecal Occult Blood Test (fecal immunochemistry test)
- See Chronic Inflammatory Diarrhea
- Other tests
- Cryptosporidium stool Antigen test
- Indicated in immune compromised state
- Fecal Leukocytes
- Consider testing stools for Laxative abuse (e.g. Anorexia Nervosa)
- Stool Laxative screen (Sodium, Potassium, Magnesium, phosphate, sulfate, Phenolphthalein, Bisacodyl)
- Fecal Chemistry Test
- Stool pH
- pH <5.5 in carbohydrate malabsorption (e.g. Lactose Intolerance)
- Fecal Electrolytes (Fecal Sodium and Osmolar Gap)
- Differentiates Chronic Watery Diarrhea category (secretory from osmotic)
- Quantitative Fecal Fat or Quantitative Sudan Microscopy (24-48 hour)
- Stool mass (24 hour)
- Quantification of Diarrhea amount
- Imaging
- Options
- CT Abdomen and Pelvis
- Abdominal MRI with enterography
- Abdominal imaging indications
- Suspected gastrointestinal structural disease
- Red flag features (see above)
- Abnormal laboratory testing
- Inflammatory Diarrhea
- Diagnostics
- Colonoscopy with biopsy Indications
- Persistent or refractory cases without identified cause
- Red flag features (see above)
- Inflammatory Diarrhea
- Formal diagnosis (e.g. Microscopic Colitis)
- Management
- Diarrhea Predominant Irritable Bowel Syndrome is a diagnosis of exclusion
- History consistent with Irritable Bowel Syndrome Rome 4 Criteria AND
- Reassuring examination AND
- Normal laboratory testing AND
- No Chronic Diarrhea red flags
- Direct to specific causes based on Diarrhea type (Diarrhea may cross categories)
- Chronic Fatty Diarrhea
- Fecal fat with sudan stain (abnormal if >14 grams/24 hours)
- Chronic Inflammatory Diarrhea
- Fecal Occult Blood Test (fecal immunochemistry test), Fecal Leukocytes, Fecal Calprotectin or lactoferrin
- Chronic Watery Diarrhea
- Loose stool without features or Chronic Fatty Diarrhea or Chronic Inflammatory Diarrhea
- References
- Frank in Friedman (1991) Medical Diagnosis, p. 186-9
- Schiller in Feldman (2002) Sleisenger GI, p. 136
- Burgers (2020) Am Fam Physician 101(8): 472-80 [PubMed]
- Juckett (2011) Am Fam Physician 84(10): 1119-26 [PubMed]
- Schiller (2004) Gastroenterology 127(1): 287-93 [PubMed]