Acute diarrhea
(Redirected from Infectious colitis)
This page is for adult patients. For pediatric patients, see: diarrhea (peds)
Background
- Almost all true diarrheal emergencies are of noninfectious origin
- 85% of diarrhea is infectious in etiology
- Viruses cause vast majority of infectious diarrhea
- Bacterial causes are responsible for most cases of severe diarrhea
- Foreign travel associated with 80% probability of bacterial diarrhea (see Traveler's Diarrhea)
Definitions
- Diarrhea: Increased frequency of defection, usually >3 bowel movements per day
- Hyperacute: 1-6 hr
- Acute: less than 3 weeks in duration
- Gastroenteritis: Diarrhea with nausea and/or vomiting
- Dysentery: Diarrhea with blood/mucus/pus
- Invasive = Infectious
Clinical Features
History
- Possible food poisoning?
- Symptoms occur within 6hr
- Does it resolve (osmotic) or persist (secretory) with fasting?
- Are the stools of smaller volume (large intestine) or larger volume (small intestine)
- Fever or abdominal pain? (diverticulitis, gastroenteritis, IBD)
- Bloody or melenic?
- Tenesmus? (shigella)
- Malodorous? (giardia)
- Recent travel? (Traveler's Diarrhea)
- Recent antibiotics? (C. diff)
- HIV/immunocompromised/high risk behaviors?
- Heat intolerance and anxiety? (thyrotoxicosis)
- Paresthesias or reverse temperature sensation? (Ciguatera)
Physical Exam
- Thyroid masses
- Oral ulcers, erythema nodosum, episcleritis, anal fissure (IBD)
- Reactive arthritis (Arthritis, conjunctivitis, urethritis)
- Suggests infection with salmonella, shigella, campylobacter, or yersinia
- Rectal exam for fecal impaction
- Guaiac
- Abdominal pain out of proportion to exam (mesenteric ischemia)
Differential Diagnosis
Acute diarrhea
Infectious
- Viral (e.g. rotavirus)
- Bacterial
- Campylobacter
- Shigella
- Salmonella (non-typhi)
- Escherichia coli
- E. coli 0157:H7
- Yersinia enterocolitica
- Vibrio cholerae
- Clostridium difficile
- Parasitic
- Toxin
Noninfectious
- GI Bleed
- Appendicitis
- Mesenteric Ischemia
- Diverticulitis
- Adrenal Crisis
- Thyroid Storm
- Toxicologic exposures
- Antibiotic or drug-associated
Watery Diarrhea
- Enterotoxigenic E. coli (most common cause of watery diarrhea)[1]
- Norovirus (often has prominent vomiting)
- Campylobacter
- Non-typhoidal Salmonella
- Enteroaggregative E. coli (EAEC)
- Enterotoxigenic Bacteroides fragilis
Traveler's Diarrhea
Evaluation
Toxigenic v. Infectious
| Characteristic | Toxic | Infectious/Invasive |
| Incubation | 2-12h | 1-3d |
| Onset | abrupt | gradual |
| Duration | <10-24h | 1-7days |
| Fever | No | Yes |
| Abdominal Pain | Minimal | Yes, tenesmus |
| Systemic | No | Yes, myalgias, nausea and vomiting |
| Physical findings | Nontoxic | Toxic |
| Abdominal Tenderness | No | Yes |
| Stool Blood, WBCs | No | Yes |
Indications for Workup
Indicated for:
- Profuse watery diarrhea with signs of hypovolemia
- Severe abdominal pain
- Fever >38.5 (101.3) (suggests infection with invasive bacteria)
- Symptoms >2-3d
- Blood or pus in stool (E. coli 0157:H7)
- Recent hospitalization or antibiotic use
- Elderly or immunocompromised
- Systemic illness with diarrhea (esp if pregnant (listeria))
Stool Studies
Fecal leukocytes
- Used to differentiate invasive from noninvasive infectious diarrheas
- Sn 50-80%, Sp 83% for presence of bacterial pathogen
- If patient has +leukocytes but negative infection consider IBD
Stool culture
- Plays minor role in ED evaluation
- Yield is only 1.5-5.5%
- Consider in patients with
- Immunosuppression
- Severe, inflammatory diarrhea (including bloody diarrhea)
- Underlying IBD (need to distinguish between flare and superimposed infection)
O&P
- Indicated if parasitic cause is suspected:
C. diff toxin
- 10% false negative rate
- Turnaround time for results varies by institution
Chemistry
- Warranted in severely dehydrated patients
CXR
- Consider if diarrhea + cough (Legionella)
Imaging
- Consider abdominal CT if abdominal tenderness or suspicion of surgical abdomen (e.g. appendicitis, small bowel obstruction, mesenteric ischemia)
- Abdominal X-ray is almost never indicated given low sensitivity for pathology (e.g. obstruction)
Supportive Therapies
Oral rehydration therapy
- Fluids should contain sugar, salt, and water
Probiotics
- Lactobacilli and bifidobacterium
- 25% decrease in average duration of diarrhea (good evidence)
Diet Modification
- Eat: BRAT(Bananas, Rice, Applesauce and Toast) diet (no evidence)
- Avoid: Caffeine (increased gastric motility), raw fruit (increased osmotic diarrhea), lactose
Bismuth subsalicylate
- Consider when loperamide is contraindicated (high fever, dysentery)
- Dose: 30 mL or 2tab q30 min for 8doses; repeat on day 2
- Caution: may cause bismuth encephalopathy in HIV patients
Loperamide
- 2mg PO per dose
- Start: 4mg PO x1, then 2mg PO after each loose stool; Max: 16mg/day
- Contraindicated if suspect C. diff
Diphenoxylate/atropine
- Dose: 4mg QID x2d
- 2nd line agent (may cause cholinergic side effects)
- Contraindicated in pseudomembranous colitis, obstructive jaundice, and children <6y
Antibiotics for Infectious Diarrhea
- Most cases of diarrhea are NOT from infectious causes. If the patient suspects that there is blood in the stool but there is no abdominal pain, and no fever, the cause is unlikely to be from a bacterial cause. Also avoid antibiotics in E. Coli 0157:H7 (EHEC) cases due the risk of Hemolytic Uremic Syndrome (HUS)[2]
- The majority of patients, even with bacterial positive cultures, will recover from diarrhea illness without antibiotic therapy[3]
Relative Indications for Antibiotics[4]
- Suspected bacterial diarrhea
- Bloody diarrhea (except for EHEC) with fever and systemic illness
- Occult blood or +fecal leukocytes
- Moderate to severe travelers' diarrhea (>4 stools/d, fever, blood, or mucus in stool)
- >8 stools/d
- Volume depletion
- >1wk duration
- Immunocompromised
- Toxic appearance
Empiric Therapy
- Ciprofloxacin 500mg PO BID x 5 days OR
- Levofloxacin 599mg PO once daily x 5 days OR
- TMP/SMX 1 DS tablet PO BID x 5 days
Traveler's Diarrhea
- Therapy should be based on the geography of travel
Adult Options:
- Ciprofloxacin 750mg PO once daily x 1-3 days[5]
- First choice for use except in South and Southeast Asia[6]
- Azithromycin 500mg PO q24h x 3 days OR 1000mg PO x 1[7]
- Rifaximin 200mg PO TID x 3 days[10]
- Ineffective against mucosally invasive pathogens (Shigella, Salmonella, Campylobacter)
- Considered very safe as it is not absorbed
Pediatric Options:
- Avoid fluroquinolones
- Azithromycin 10mg/kg/day once daily x 3 days OR[11]
- Ceftriaxone 50mg/kg/day once daily x 3 days
Culture Specific Antibiotics
| Agent | Treatment |
| Clostridium difficile |
|
| Campylobacter jejuni |
|
| Entamoeba histolytica |
|
| Giardia lamblia |
|
| Microsporidium |
|
| Cryptosporidium |
|
| Salmonella (non typhoid) |
Options: Immunocompromised patients should have 14 days of therapy
|
| Shigella | Treatment extended for 10 days if immunocompromised'
|
| Vibrio Cholerae |
|
| Yersinia enterocolitica | Antibiotics are not required unless patient is immunocompromised or systemically ill
|
Disposition
- Hospitalization should be individualized based on the patient's ability to tolerate oral hydration, have adequate social support, and also based on complicating comorbidities.
- Majority of patients can be treated as an outpatient
- Observation or admission is required for those with severe disease, and significant dehydration with other end organ complications
See Also
References
- ↑ Marx et al. “Cholera and Gastroenteritis caused by Noncholera Vibrio Species”. Rosen’s Emergency Medicine 8th edition vol 1 pg 1245-1246.
- ↑ Aranda-Michel J et al. Acute diarrhea: A practical review. AmJMed. 1999;106:670-676.
- ↑ DuPont HL et al. Practice Parameters Committee of the American College of Gastroenterology. Guidelines on acute infectious diarrhea in adults. Am J Gastroenterol. 1997;92:1962-1975.
- ↑ IDSA Practice Guidelines for the Management of Infectious Diarrhea. 2001. fulltext
- ↑ Hoge CW. et al. Trends in antibiotic resistance among diarrheal pathogens isolated in Thailand over 15 years. Clin Infect Dis. 1998;26:341–5
- ↑ Steffen R, et al. Traveler’s Diarrhea: A Clinical Review. JAMA. 2015;313(1):71-80. doi:10.1001/jama.2014.17006
- ↑ Sanders JW. et al. An observational clinic-based study of diarrheal illness in deployed United States military personnel in Thailand: presentation and outcome of Campylobacter infection. Am J Trop Med Hyg. 2002;67:533–8
- ↑ Steffen R, et al. Traveler’s Diarrhea: A Clinical Review. JAMA. 2015;313(1):71-80. doi:10.1001/jama.2014.17006
- ↑ Steffen R, et al. Traveler’s Diarrhea: A Clinical Review. JAMA. 2015;313(1):71-80. doi:10.1001/jama.2014.17006
- ↑ DuPont HL. et al. Rifaximin versus ciprofloxacin for the treatment of traveler’s diarrhea: a randomized, double-blind clinical trial. Clin Infect Dis. 2001;33:1807–15
- ↑ Stauffer WM, Konop RJ, Kamat D. Traveling with infants and young children. Part III: travelers’ diarrhea. J Travel Med. 2002;9:141–50