Infections of GI tract: Infectious Diarrhea-Schoenwald- Exam 3 Flashcards
Infectious Diarrhea:
- onset?
- MC outbreaks?
- What hx do you need from the Pt?
- Acute in onset and lasting <2 weeks
- Community outbreaks (nursing homes, schools, cruise ships) suggest viral etiology or common food source
- Get travel history
Noninflammatory Diarrhea= watery, ________ diarrhea
nonbloody
Noninflammatory diarrhea:
- associated Sx?
- disrupts?
- Associated with cramping, bloating, nausea, vomiting
- Disrupts normal absorption in small bowel
T/F: In Noninflammatory diarrhea Tissue invasion does not occur.
-NO _____ _______ on smear
True! Tissue invasion does not occur-no fecal leukocytes on smear
Inflammatory Diarrhea= fever and _____ diarrhea
bloody
Inflammatory Diarrhea:
-causes ______ tissue damage
colonic
invasion of bacteria or toxin
Inflammatory diarrhea:
involves primarily the _____ colon
lower colon–>left lower quadrant cramping, urgency
Inflammatory Diarrhea:
-fecal ________ present because of invasion of mucosa
fecal leukocytes
DDx for inflammatory diarrhea
ulcerative colitis
Inflammatory diarrhea:
-Diarrhea >14 days most likely NOT due to _______ agent
infectious agent (except C diff)
Why do we classify as inflammatory or noninflammatory diarrhea?
- Major difference is colonic tissue invasion by the organism and/or toxin
- Helps to differentiate when it is “okay” to use promotility agents-Imodium
DO NOT use ______ agents in inflammatory diarrhea
promotility
Typical Stool Pathogens
- Salmonella
- Shigella
- Campylobacter
- Vibrio
- E coli O157:H7
- Clostridium diff: pseudomembranous colitis
- Norovirus
- Enterovirus
- Parasites-Giardia, Amoeba, Cyptosporidium
Causes of Acute Infectious Diarrhea: Noninflammatory (list examples)
- Enterotoxin production
- Norovirus
- Rotavirus
- Giardia
- Cryptosporidium
- Listeria monocytogenes
Acute infectious diarrhea:
-list the pathogens that are specifically associated with enterotoxin production (4 of them)
Staph aureus
Bacillus cereus
Enterotoxigenic E coli
Vibrio cholerae
Causes of Acute Infectious Diarrhea: inflammatory (list examples)
- Cytotoxin production
- Mucosal invasion
- Cytomegalovirus
- Entamoeba histolytica
Acute Infectious Diarrhea: inflammatory
-list the specific organisms associated with Cytotoxin production
- Enterohemorrhagic E coli 0157:H7
- Clostridium difficile
Acute Infectious Diarrhea: inflammatory
-list the specific organisms associated with Mucosal invasion
- Campylobacter
- Shigella
- Salmonella
“think-> invasion “make camp” (=campylobacter and make salmon (salmonaella)
Inflammatory Diarrheas:
-(list 5)
- Clostridioides difficile (new name)–>Previously Clostridium difficile
- Salmonella
- Shigella
- Campylobacter
- Escherichia coli 0157:H7
Clostridioides difficile (Clostridium difficile):
- main Sx is _____
- major risk factors?
- diarrhea
- Previous antibiotic usage(historically **clindamycin, penicillins and cephalosporins)
- Advanced age
- Previous hospitalization
- Nursing home resident
C difficile– the new definition:
- Presence of which Sx?
- incidence has _____ from 2000-2005
- CDI-C diff infection
- Presence of Sx in the form of 3 or more unformed stool over 24 hours for 2 consecutive days in conjunction with positive stools for pseudomembranes
- Prior antimicrobial use not included in new guidelines
- Incidence had tripled from 2000-2005
C difficile:
- clinical findings?
- _____ diarrhea
- ____ bowel movements per day
- fever present?
- Can lead to _____ _____ and colectomy
- **Watery diarrhea
- 15-30 bowel movements/day
- Abdominal pain or cramps
- Fever-low grade
- *Can lead to toxic megacolon and colectomy
C diff-lab findings
- Leukocytosis-often with bandemia (**left shift)
- Hypoalbuminemia
- *Positive stool C diff test
Lab Tests for C diff:
-list 3
- Molecular test-PCR
- –Highly sensitive and specific
- –Can be positive in asymptomatic patients
- Antigen detection–> nonspecific
- Toxin testing: Toxin A and B testing –high rate of false negatives
(do toxin testing first, if that’s negative, follow-up w/ PCR)
Initial Episode of C diff: mild/moderate
-leukocytosis?
-Creatine ?
Tx?
Leukocytosis <15000,Creat <1.5
tx: Vancomycin 125 mg po qid x 10 days OR Fidaxamin 200 mg po bid x 10 days
note: fidaxamin is expensive!!
Initial Episode of C diff: Severe
-leukocytosis?
-Creat.?
Tx?
Leukocytosis >15000, Creat >1.5 prior to CDI
tx:Vancomycin 125 mg po qid x 10 days OR fidaxamin 200 mg po bid x 10 days
Initial Episode of C diff: complicated
-sx?
Tx?
Hypotension or shock,perforation, megacolon
tx: Vancomycin 500 mg po qid or via NG tube and/or metronidazole 500-750 mg IV q 8 hrs
C diff: 1st recurrence
tx?
Vancomycin oral taper or Fidaxamin
C diff: 2nd recurrence
tx?
Vancomycin oral taper or Fidaxamin
-Fecal microbiota transplant
C diff prevention (2 main things):
- antibiotic _______
- Environmental _____ and hand hygiene
- Spores can live up to __ months on a surface
- Antibiotic stewardship
- Environmental control and hand hygiene
- -Spores can live up to 5 months on a surface
- -Health care worker important vector
- -Alcohol hand preps ineffective
- -For surfaces, chlorine based disinfectants effective
Salmonella”
- a gram _____ rod
- carried in the ___
- gram negative rod, Salmonella enteriditis
- Carried in GI tract of reptiles, bird
Salmonella:
- ____ million cases per yr in US
- most cases occur from?
- 3.7 million cases
- Most cases occur from eating contaminated meat or eggs or from infected food handlers
- Also associated with handling reptiles
Salmonella:
- Pts can remain culture positive for __ month(s) after treatment
- incubation period=
- 1 month after treatment–> can be long term carrier
- -Incubation 6-48 hrs
Salmonella:
- clinical sx?
- T/F: bloody stools are common
- Fever and diarrhea MC Sx
- Usually self limited
- Bloody stools uncommon
Salmonella:
______ up to 4% of time in previously healthy with gastroenteritis
-Metastatic spread to _____
- bacteremia
- Metastatic spread to vascular grafts, joints, kidneys and liver common in bacteremic patients