Acute Diarrhea Flashcards
Diarrhea vs acute Diarrhea vs chronic Diarrhea
Diarrhea: > 3 loose stools per day
Acute Diarrhea: < 2 weeks duration
Chronic Diarrhea: > 3 weeks duration
Gastroenteritis
diarrhea w/ nausea & vomiting
Dysentery
diarrhea w/ blood, mucus, pus
Osmotic diarrhea / secretory diarrhea
Osmotic Diarrhea (sorbitol): solutes in lumen draw/keep water in lumen
Secretory Diarrhea (Cholera): intestinal secretion of solutes and water into lumen
when to use diagnostics for diarrhea
Diagnostics: reserved for severe dehydration or illness, persistent fever, bloody stool, immunosuppression, cases of suspected nosocomial infection or outbreak
antibiotics should be considered for which pathogens
shigella, campylobacter, Clostridioides difficile, traveler’s diarrhea, protozoal infections
noninfectious / infectious diarrhea / infective colitis
Noninfectious diarrhea: lack of constitutional symptoms
Infectious diarrhea: large volume (often watery) stool, constitutional symptoms, nausea/vomiting/abdominal cramps (gastroenteritis)
Infectious colitis: fever, tenesmus, and dysentery
Non-inflammatory Diarrhea
general
Sx and pathogens
Usu viral (some bacterial, parasitic)
Intestinal secretion, mucosa intact (cells are not damaged)
No fever, no blood in stool
No fecal leukocytes
Norovirus, rotavirus, Cholera, enterotoxigenic E coli, Staph aureus, Giardia…
inflammatory diarrhea
General
Sx and pathogens
Usu invasive, toxin-producing bacteria
Mucosa damaged (hence blood and WBCs)
Fever, bloody stool
Fecal leukocytes
Shigella, Campylobacter, C diff, some Salmonella, Shiga-toxin E coli
High Yield Associations of Diarrhea
Daycare
Rotavirus common
Multiple pathogens possible
High Yield Associations of diarrhea
Travel
Enterotoxigenic E coli (ETEC)
Norovirus outbreaks on cruise ships (and locally)
High Yield Associations of diarrhea
Animals
Animals
Turtles, reptiles = Salmonella
High Yield Associations of diarrhea
Food and water
Foods
Eggs & Dairy = Salmonella
Water (Camping)
Streams = Giardia
Toxin-mediated “Food Poisoning”
Bacterial toxin
abrupt onset (1-8 hours after ingestion)
vomiting prominent (diarrhea minimal)
resolution usually < 24 hours
E. Coli (ETEC) Classic “Traveler’s Diarrhea”
Contaminated food / water
Symptoms:
anorexia, cramps, watery diarrhea, low grade fever
may be nausea & vomiting—not prominent
no pus or bloody stools
Rotavirus
general
Common cause of acute diarrhea hospitalizations in children
Winter prevalence
Viral shedding: 21 days
Acute onset, may be fever
vaccine available
Noravirus
General
Common cause of
diarrheal epidemics
Acute onset:
nausea & vomiting
watery diarrhea
abdominal cramps
lasts 1-3 days
If blood is present you culture, possible offenders?
Campylobacter
Salmonella
Shigella
E. coli / E. coli O157:H7
Campylobacter
general and Sx
Common Bacterial Pathogen
contaminated food (poultry)
contact with fecal material/animal-to-person
Symptoms:
diarrhea +/- blood
abdominal cramps / pain
fever
usually self-limited—may not require antibiotics
Salmonella
General and Sx
Common in children < 4 years old
contaminated food (poultry)
infected animals (turtles)
Symptoms:
fever
diarrhea +/- blood
abdominal cramping/pain
usually self-limited—usually does not require antibiotics
Shigella
general and Sx
“Shiga toxin”— toxic to enterocytes
Symptoms:
fever
abdominal cramps/pain
tenesmus–mucoid stools +/- blood
abx shorten duration of illness, limit fecal shedding
E. Coli O157: H7 (Shiga toxin)
general and Sx
Contaminated food / water
Symptoms:
bloody diarrhea– not typical Traveler’s Diarrhea
severe abdominal cramps
high fever (> 101.3)
do not use abx, abx increase risk of complications (HUS)
Clostridium difficile (C diff)
general
Associated with antibiotic use
Major diarrhea cause in pts hospitalized >3 days (consider in all hospitalized patients with unexplained leukocytosis)
Greenish, foul, watery diarrhea 5–15 x daily, rarely bloody;
PE: normal or mild LLQ tenderness.
C diff
PE findings
PE: normal or mild LLQ tenderness.
Severe/fulminant: profuse diarrhea (≥ 30 stools/day); PE: fever; hemodynamic instability; abdominal distention, pain, tenderness
C Diff
Labs
Labs suggestive of severe = WBC >30,000, albumin < 2.5 (due to protein-losing enteropathy), elevated serum lactate, rising Cr
Stool toxin/antigen assay
C diff
CT
Noncontrast abdominal CT scans if severe/fulminant to look for colonic dilation and wall thickening
C diff increases risk for toxic mega colon
C diff
Tx
Complex antibiotic decision tree
Prevention: minimize antibiotic use, don’t suppress gastric acid
parasites
Contaminated food, water, person
Gradual onset, can be chronic
Watery, persistent, non-bloody diarrhea
Vomiting not prominent
Malabsorption
Foul smelling stool
Weight loss
Giardia, Entamoeba histolytica, Cryptopsporidium
Symptoms that call for workup / culture
Usually not, but some exceptions:
weight loss / dehydration
bloody diarrhea
severe abdominal pain
recent abx use
immune suppressed/ associated illness/ elderly
high fever (> 101.3)
Shigella, campylobacter, C diff, severe traveler’s diarrhea, protozoal infections – NO ANTIOBIOTICS for E. Coli O157: H7
Workup options
Stool culture, Giardia antigen testing, O&P
Fecal leukocytes/Fecal lactoferrin
C diff testing
CBC with diff
Electrolytes
Renal function testing
Tx options for diarrhea
Oral rehydration therapy/early refeeding for dehydration
IV fluids as needed
Avoid antimotility agents if bloody diarrhea
Probiotics? may shorten duration of sx
probiotics should be 11 billion CFU
Anti-motility
Meds
For symptomatic relief if:
no significant fever
non-bloody stools
Agents:
Loperamide (OTC)
Pepto-Bismol (OTC)
Kaopectate (OTC)
Lomotil (Rx) = narcotic + atropine
Diarrhea
when to admit
ADMIT if:
Severe dehydration / unstable VS
Bloody diarrhea with anemia
Severe abdominal pain & recent abx use
Significant comorbidities
N/V
general
Acute symptoms = usually infectious, inflammatory, or iatrogenic
Most infections self-limiting and require minimal intervention; iatrogenic causes resolved by removing offending agent
N/V
Chronic Sx
Chronic symptoms - variety of conditions
GI: obstruction, functional disorders, organic diseases
CNS: increased intracranial pressure (typically additional neurologic signs)
Pregnancy - most common endocrine cause of nausea, consider in any woman of childbearing age
Metabolic abnormalities, psychiatric diagnoses
Evaluation: focus on detecting emergencies or complications that require hospitalization
N/V
when cause is not certain
When cause not certain, empiric therapy with antiemetic is appropriate
Initial diagnostic testing should be limited to basic labs and plain radiography. Further testing, such as EGD or CT of abdomen, should be determined by clinical suspicion based on complete Hx and PE
Colic
Sharp, localized abdominal pain that increases, peaks, and subsides
Associated with numerous diseases of hollow viscera
Mechanism of pain: smooth muscle contraction proximal to partial or complete obstruction (gallstone, kidney stone, small bowel obstruction)
Location may help diagnose cause
Absence of colic useful for ruling out acute cholecystitis (only < 25% of patients with acute cholecystitis present without RUQ colic)
