Acute and Chronic Diarrhea

Question 1

acute diarrhea

Answer 1

-Diarrhea: persisting < 2 weeks
-Infectious agents, bacterial toxins or meds
-Most cases are likely viral- self limiting
-non-inflammatory and inflammatory

Question 2

Diarrhea

Answer 2

-Increased stool frequency:
-> 3BM/day
OR
-Liquidity of feces*
OR
-Stool weight >200–300g/24 h
-get pts baseline/normal
-note which problem it is

Question 3

bacteria, virus, protozoa: acute diarrhea

Answer 3

-take away- many causes, can be small bowel or colon affected, different symptoms
-bacteria- salmonella, e coli, clostridium perfringens, staph aureus (VOMITING, old food, coming out both ends), aeromonas hydrophilia, bacillus cereus, vibrio cholerae
-virus- rotavirus, norovirus, astrovirus
-protozoa- cryptosporidium, microsporidium, cystoisospora, cyclospora, giardia lamblia

Question 4

where and how diarrhea contracted

Answer 4

-Community outbreaks (nursing homes, schools, cruise ships)- Viral or food source
-Exposure to unpurified water- Giardia (not immune compromised) or Cryptosporidium (immune compromised)
-Contaminated produce- Cyclospora outbreaks
-Antibiotic administration- Clostridium difficile colitis
-Contaminated meat- E. coli, salmonella
-anal intercourse- e. coli

Question 5

vomiting microbes (chart)

Answer 5

-s aureus***- food left out, picnic
-b cereus
-norwalk like viruses
-old food

Question 6

watery diarrhea microbes

Answer 6

-c perfringens
-enterotoxigenic e coli** - fecal oral
-enteric viruses** norovirus - fecal oral
-c parvum
-c cayetanensis
-food or water contaminated

Question 7

inflammatory diarrhea

Answer 7

-often involves bleeding
-campylobacter spp
-nontyphoidal salmonella
-shiga toxin producing e coli*
-shigella spp*
-v parahemolyticus
-vibrio- shellfish
-food and water
-can have more than one strain -> shiga toxin producing e. coli and entertoxigenic e coli (watery diarrhea) - common

Question 8

non-inflammatory acute diarrhea

Answer 8

-SMALL BOWEL
-Secretory* process in small intestine-
-Stimulates secretion into bowel or decrease absorption
-Periumbilical cramps, bloating, nausea, or vomiting
-Watery, non-bloody diarrhea- Usually mild but can be voluminous -> Tissue invasion does not occur -> fecal leukocytes are not present in stool**
-voluminous- hypokalemia, metabolic acidosis, dehydration

Question 9

causes of non-inflammatory diarrhea

Answer 9

-viral- noroviruses, rotovirus
-protozal- giardia lamblia, crytosporidum, cyclospora
-bacterial:
-preformed enterotoxin production (consume toxin)- s. aureus, bacillus cereus, clostridium perfringens
-enterotoxin production (produced inside body) - enterotoxigenic e. coli, vibrio cholerae
-e coli- travelers diarrhea- drinking unpure water
-SMALL BOWEL

Question 10

inflammatory acute diarrhea

Answer 10

-COLON
-Colonic* tissue damage caused by INVASION or TOXIN production:
-Invasion: Shigellosis, Salmonellosis, Campylobacter or Yersinia infection, Amebiasis
-Toxin: C difficile, E coli O157:H7
-Fever, bloody diarrhea - Diarrhea is small volume (< 1 L/d)
-LLQ cramps, urgency, and tenesmus (need to go to bathroom)
- + Fecal leukocytes (usually)
-smaller volume of diarrhea than non inflammatory

Question 11

most common cause of bloody diarrhea

Answer 11

-e. coli O157:H7 is a toxin producing noninvasive** organism
-organism not invading but the toxin!!
-inflammatory- colon
-MC- contaminated meat
-acute, often severe hemorrhagic coliotis
-less common are shigella, campylobacter, and salmonella species

Question 12

evaluation of acute diarrhea

Answer 12

-90% with acute non-inflammatory diarrhea:
-mild and self limited*
-bland diet, limit dairy
-approx 5 days
-dx investigation unnecessary - by the time you have results the disease is typically gone…
-goal of initial eval- determine mild disease vs more serious illness

Question 13

physical exam- assess

Answer 13

-Hydration
-Mental status
-Abdominal tenderness
-Hospitalize: Marked dehydration, toxicity, or marked abdominal pain

Question 14

when to obtain stool specimens

Answer 14

-Severe illness (fever ≥101.3°F), hypovolemia, ≥6 unformed stools per 24 hours, severe abdominal pain, or hospitalization, hypotensive, high pulse
-Features of inflammatory diarrhea (bloody diarrhea, small volume mucous stools, fever) -> get sample if blood
-High-risk host features (age ≥70 years, cardiac disease, immunosuppression, inflammatory bowel disease, pregnancy)
-Symptoms persisting >1 week
-Public health concerns that are persisting (eg, diarrheal illness in food handlers, health care workers, and individuals in day care centers)
-* consider empiric therapy if sick enough

Question 15

stool w/u for acute diarrhea

Answer 15

-Fecal leukocytes (chronic diarrhea)- IBD
-Ovum and parasite
-Bacterial culture
-C diff - sterile cup
-Giardia antigen
-viruses
-all in one vial now :)
-***Newer tests are all in one
Order GI pathogen panel PCR if available

Question 16

treatment for acute diarrhea

Answer 16

-diet- no caffeine
-fluids
-probiotics- most helpful in c diff
-carbs
-small frequent meals
-antidiarrheal agents - NOT RECOMMENDED can bottle up the infection in acute diarrhea like Imodium (pepto bismol is ok bc its antimicrobial)
-antibiotic therapy- empiric antibiotic -> not usually needed -> if severe/bloody etc. -> MC cipro, levofloxacin or azithromycin

Question 17

specific treatments of acute diarrhea

Answer 17

-Shigellosis: Fluoroquinolone
-Cholera: Doxycycline or Azithromycin
-Traveler’s diarrhea: Fluoroquinolone
-C. difficile infection- Vancomycin
-Giardiasis, and amebiasis: Metronidazole or Tindazole (one day) *

Question 18

chronic diarrhea

Answer 18

-Decrease in fecal consistency lasting ≥4 wks
-Types:
-Osmotic
-Secretory
-Inflammatory
-Malabsorption
-Motility Disorders
-Chronic Infections

Question 19

chronic: osmotic diarrhea

Answer 19

-lactose intolerance
-Retention of solute molecules within the bowel lumen generates osmotic forces that retard the normal absorption of water or draw water from the circulation into the intestinal lumen
-influx of fluid into lumen
-causes:
-Disaccharidase deficiency- lactose intolerance
-Lactulose- causes diarrhea (poop out ammonia with encephalopathy)
-Sorbitol- artificial sweetener, not absorbable -> fluid pulling small bowel
-Olestra- fat substitute, not absorbable
-Magnesium containing medications and laxatives- draws water into bowel -> also magnesium supplements

Question 20

secretory diarrhea: chronic

Answer 20

-Increased intestinal secretion (fluid into lumen) or decreased absorption
-watery diarrhea
-High-volume watery diarrhea and diarrhea with fasting
-not food mediated- can occur with fasting**
-Dehydration/electrolyte imbalance may develop
-Causes:
-Endocrine tumors
-Bile salt malabsorption
-Laxative abuse

Question 21

inflammatory diarrhea: chronic

Answer 21

-Diarrhea is present in most patients with IBD- Ulcerative colitis, Crohn’s disease
-Other symptoms present: Abdominal pain, fever, weight loss, and hematochezia

Question 22

malabsorption syndromes: chronic

Answer 22

-The major causes are:
-Small intestinal mucosal diseases - MC celiac (malabsorption of gluten)
-Intestinal resections- malabsorption of fat
-Lymphatic obstruction- malabsorption of fat
-Small intestinal bacterial overgrowth
-Pancreatic insufficiency- cant digest and absorb
-Weight loss, osmotic diarrhea, steatorrhea, and nutritional deficiencies

Question 23

motility disorders: chronic

Answer 23

-Abnormal intestinal motility causes:
-Rapid transit- dumping syndrome
-Stasis of intestinal contents with bacterial overgrowth
-IBS
-bowel resection
-dumping syndrome

Question 24

chronic infections

Answer 24

-Chronic parasitic infections:
-Immune competent parasite: Giardia, E. histolytica, and Cyclospora
-Immunocomproised: Microsporida, Cryptosporidium, CMV, Isospora belli, Cyclospora, and Mycobacterium avium complex (HIV, chemo)
-C. Diff- immune competent bacterial -> toxin -> long term
-Post infectious IBS- had infection and its gone -> leaves you with irritable bowel

Question 25

factitious diarrhea: chronic

Answer 25

-taking something that causes diarrhea
-Fifteen percent of patients have factitious diarrhea caused by laxative abuse
-90% women

Question 26

evaluation of chronic diarrhea

Answer 26

-Exclude:
1. Causes of acute diarrhea
2. Lactose intolerance, Celiac Ds
3. Previous gastric surgery or ileal resection
4. Parasitic infections, C diff risk factors
5. Medications hx- diabetic meds can cause diarrhea
6. Systemic disease ie. IBD- hyperthyroidism

*see PDF

Question 27

history for chronic diarrhea

Answer 27

-A clear understanding of what led the patient to complain of diarrhea
-Stool characteristics- frequency, liquid, fasting, with food
-Duration of symptoms, nature of onset
-Travel, meds, diet
-Risk factors for HIV infection, sexual hx
-Family history - celiac, IBD
-Systemic symptoms
-Fecal incontinence*- inability to hold onto stool

Question 28

physical for chronic diarrhea

Answer 28

-Rarely a specific diagnosis but clues to causes:
-IBD
-Malabsorption
-Lymphadenopathy- HIV, lymphoma
-Thyroid- graves (can cause diarrhea)
-scars from surgery
-anemia
-anal fissure, mouth ulcer

Question 29

blood lab testing for chronic diarrhea

Answer 29

-CBC- anemia?
-ESR, CRP- nonspecific inflammation?
-Thyroid function tests- hyperthyroid?
-Electrolytes- dehydration?
-Total protein and albumin- nourished?
-Celiac sprue- celiac panel for patients with chronic

Question 30

stool tests for chronic diarrhea

Answer 30

-Infection- c diff is chronic
-Occult Blood
-Fecal Elastase - pancreas enzyme abnormalities (aging can replace pancreas with fat)
-even if pts are taking pancreatic replacement this still look falsely low with chronic diarrhea infections
-fecal elastase can look low
-Fecal Calprotectin - marker for WBC, elevated in acute infection or IBD (can be high before IBD dx too! -> follow up)

Question 31

alarm features in pts with chronic diarrhea****

Answer 31

-age onset after 50
-rectal bleeding or melena
-nocturnal pain or diarrhea (unless lactose intolerant) - diarrhea usually resolves overnight
-unexplained weight loss, fever, systemic symptoms
-lab abnormalities (iron deficiency anemia, elevated ESR/CRP, elevated fecal calprotectin, fecal occult blood present)
-first degree relative with inflammatory bowel disease or colorectal cancer or celiac

Question 32

IBS

Answer 32

-diagnosis of exclusion
-rule everything else out
-often younger population

Question 33

endoscopy

Answer 33

-Sigmoidoscopy or colonoscopy with mucosal biopsy - Inflammatory bowel disease, melanosis coli, c diff (stool specimen first), collagenous and lymphocytic colitis (colon infiltrated with collagen or lymphocytes) -> only dx with bx

-EGD with small bowel biopsy
-CELIAC GOLD STANDARD
-Small intestinal malabsorptive disorder is suspected (celiac sprue, Whipple’s disease) -> these typically stool sample
-must confirm celiac with bx
-crohns- can be anywhere for from mouth to anus -> EGD and colonoscopy

Question 34

collagenous and lymphocytic colitis

Answer 34

-colon is infiltrated with collagen
-colon is infiltrated with lymphocytes
-chronic diarrhea
-intermittent
-sigmoidoscopy or colonoscopy bx

Question 35

additional testing for chronic diarrhea

Answer 35

-Small intestinal bacterial overgrowth
-Lactose tolerance test
-these are breath tests

Question 36

imaging studies to consider for chronic diarrhea

Answer 36

-abdominal CT scan- pancreatitis, severe abdominal pain
-small bowel series or MR enterography- pts at risk for crohns
-somatostatin receptor scintigraphy- neuroendocrine tumors (ZE syndrome) - DONT WORRY AB THIS

Question 37

treatment for chronic diarrhea

Answer 37

-TREAT UNDERLYING CONDITION*****
-antidiarrheal agents- BAD CHOICE- loperamide, diphenoxylate with atropine
-anticholinergics/antispasmodics -> dicyclomine and hyoscyamine - IBS

Question 38

bile salt-binding resin

Answer 38

-treatment for ileal resections - bile salt induced diarrhea
-cholestyramine:
-useful in patients with bile salt-induced diarrhea secondary to intestinal resection or ileal disease
-4 g (1 packet) once to three times daily