Infectious Diarrhea Flashcards
How long does acute diarrhea typically last?
Less than 2 weeks (except for C. diff)
Community outbreaks of acute diarrhea typically suggests which of the following:
Viral etiology
Bacterial pathogen
Common food source
Viral etiology or common food source
Describe stool in noninflammatory diarrhea.
Watery diarrhea without blood
Fecal smear of noninflammatory diarrhea does NOT have _______
Fecal leukocytes
Describe stool in inflammatory diarrhea.
Bloody diarrhea
Typical symptoms associated with noninflammatory diarrhea?
Cramping, bloating, nausea, vomiting
Typical symptoms associated with inflammatory diarrhea?
Fever, LLQ pain, urgency
Inflammatory diarrhea causes blood and fecal leukocytes to be present. Why?
Bacteria or toxin invades colonic tissue causing tissue damage
In what type of diarrhea is it okay to use promotility agents or antimotility agents?
Non-inflammatory diarrhea
Why shouldn’t you use promotility or antimotility agents in inflammatory diarrhea?
Promotility: risk of dehydration
Antimotility: allows bacteria and toxin to stay in place for a longer amount of time
Bacteria that produce enterotoxin cause noninflammatory diarrhea. What bacteria produce enterotoxin?
Staph aureus, Bacillus cereus, Enterotoxigenic E. coli, Vibrio cholerae
What are the other causes of noninflammatory diarrhea?
Norovirus, Rotavirus, Giardia, Cryptosporidium, Listeria monocytogenes
What cytotoxin producing bacteria cause inflammatory diarrhea?
Enterohemorrhagic E coli. 0157:H7, C. Diff
What are the mucosal invading pathogens of inflammatory diarrhea?
Camylobacter, Shigella, Salmonella
What two other pathogens of inflammatory diarrhea?
Cytomegalovirus, Entamoeba histolytica
Risk factors for C. diff infections?
Antibiotics use, typically clindamycin, penicillin, and cephalosporins
What symptoms must be present for C. diff infection?
Three or more unformed stool over 24 hours for 2 consecutive days in conjunction with positive stools for pseudo membranes
Lab findings in C. diff?
Leukocytosis with left shift
Hypoalbuminemia
Positive stool C. diff test
What is the correct sequence of C. diff tests to order?
Toxin testing, if negative, consider PCR
Downside of C. diff PCR test?
It is so good it can pick up asymptomatic carriers.
We don’t really know what to do for them, so try not to go there
First line treatment for C. Diff?
Vancomycin 125mg PO QID
Treatment for C. diff accompanied by hypotension or shock or toxic megacolon?
Vanco 500 PO QID+/- metronidazole
Treatment for 2nd recurrence of C. diff?
Vanco oral taper
Fecal microbiota transplant
What new medication works as well as vanco for C. diff?
Fidaximin
Salmonella most commonly from acquired from?
Contaminated meat or eggs
Infected food handlers
Incubation period for salmonella?
6-48 hours
Common symptoms of salmonella?
Fever and diarrhea
Treatment for uncomplicated salmonella?
Supportive care - it is self limiting
Treatment for complicated salmonella?
Cipro
Typhoid fever is caused by what bacteria?
Salmonella typhi
T/F? Typhoid fever is endemic in US
False
Symptoms of typhoid fever?
Diarrhea or constipation, maculopapular rose color skin rash, fever, abd pain, weakness
Diagnosis of typhoid fever is?
Clinical diagnosis + travel history
Treatment for typhoid fever?
Azithromycin for mild cases.
Carbapenems for severe cases
Most common ways to spread shigella?
Inanimate objects*** - think day care
Fecal oral
Flies
Symptoms of shigella?
Diarrhea (bloody, watery, purulent, and mucous) Fever Stomach cramps Nausea Emesis Dehydration
Treatment for shigella?
Cipro
Most common cause of bacterial GI symptoms?
Campylobacter
One symptom of campylobacter that differentiates it from other causes of infectious diarrhea is what?
A prodrome of fever, headache, myalgia, and malaise
Treatment for campylobacter?
Cipro
Complication of campylobacter?
Guillain Barre syndrome
Most common cause of “traveler’s diarrhea”?
Enterotoxigenic E coli shiga toxin + or -
Main cause of HUS in US?
E Coli 0157:H7
Sources of E oli 0157
Undercooked ground beef, unpasteurized juices and milk
Triad of HUS symptoms?
Renal insufficiency
Hemolytic anemia
Thrombocytopenia
Treatment for E coli 0157?
Supportive
Most common cause of staph food poisoning?
Foods with high salt or sugar - think cream sauces, custard, hams, canned meat
Onset of staph food poisoning?
Rapid 4-8 hours
Treatment for staph food poisoning?
Supportive care
Staph food poisoning typically lasts no longer than _____
24 hours
What noninflammatory diarrhea can cause spontaneous abortion, sepsis, bacteremia, and meningitis?
Listeria monocytogenes
Treatment for listeria?
Ampicillin
Diagnosis of this noninflammatory diarrhea is done by stool culture or PCR.
Enterotoxigenic E coli non 0157 strains
Treatment options for enterotoxigenic e coli?
Cipro
Common sources of Vibrio cholera infections?
Poor water sanitation, shellfish
Incubation period of Vibrio cholera?
12-72 hours
Description of stools in cholera?
“rice water stools”
Treatment for Vibrio cholera?
HYDRATION!!!!
and doxycycline or cipro
Most common cause of nonbacterial gastroenteritis?
Norovirus
Gold standard test for norovirus?
Stool culture
Does the following pathogen cause infectious or non infectious diarrhea? Staph aureus Vibrio cholerae Shigella Giardia Cytomegalovirus Campylobacter C. diff Rotavirus Giardia Salmonella E coli 1057:H7 Bacillus cereus Enterotoxigenic E coli Listeria
Staph aureus - noninflammatory Vibrio cholerae - noninflammatory Shigella - inflammatory Giardia - noninflammatory Cytomegalovirus - inflammatory Campylobacter - inflammatory C. diff - inflammatory Rotavirus - noninflammatory Entamoeba histolytica - inflammatory Salmonella - inflammatory E coli 1057:H7 - inflammatory Bacillus cereus - noninflammatory Enterotoxigenic E coli - noninflammatory Listeria - noninflammatory
