Acute Diarrhea- Piburn Flashcards
what are the types of diarrhea
decreased absorption of h20
increased intestinal secretion
increased osmotic load
abnormal motility
what is the most common cause of diarrhea
infection
what are high risk groups for diarrhea
travelers
ingesting certain foods
immunodeficiency
daycares
institutionalized
extremes of age
what are infectious agents that travelers are at risk for
campylobacter
norovirus
coronavirus
salmonella
shigella
Giardia (Beaver fever)
what is the most common agent seen in daycares
rotavirus
what is non-inflammatory acute diarrea
watery, not bloody
GI symptoms
larger volumes (+/- dehydration)
fecal leukocytes absent
small intestine
what is inflammatory acute diarrhea
blood diarrhea (dysentery)
systemic symptoms (fever) + LLQ cramping, urgency and tenesmus
small volumes
fecal leukocytes present
large intestine
what are non-infectious causes of acute diarrhea
malabsorption
Celiac, IBS, Crohn’s, UC, medications, bile acids, mesenteric ischemia
what are possible acute diarrhea work up tests
CBC, CMP
fecal leukocyte count
fecal hemoccult
stool culture - bacterial
+/- C. diff PCR
+/- viral testing, protozoal testing
+/- ova and parasite testing
if diarrhea persists, what are other workup tests that can be completed
flexible sigmoidoscopy- colonoscopy (biopsy)
Radiographs or CT scan
r/o IBD, ischemic colitis, or other non-infectious causes
what is the supportive treatment for acute diarrhea
maintain adequate oral intake
bowel rest
easy digestible foods
oral rehydration with electrolytes
anti-diarrheals
what is the BRAT diet
Banana, Rice, Apple sauce, toast
when is anti–diarrheal contraindicated
blood diarrhea, fever, systemic symptoms, persistent diarrhea
if concern for toxic megacolon
what criteria must be met for empiric antibiotic treatment for acute diarrhea
no concern for hospital acquired infection
presents of moderate to severe fever, tenesmus or bloody stools
no suspicion for E.coli - abx increase risk of HUS
what is the preferred abx for acute diarrhea
fluoroquinolone
-ciprofloxacin, ofloxacin, levofloxacin
bactrim or doxycycline
what is HUS
hemolytic uremic syndrome
blood break down, increased urea - results from blood clots, predominantly in the kidney
what is the criteria to admit for acute diarrhea
severe dehydration, especially if vomiting or unable to tolerate PO intake
severe or worsening bloody diarrhea
severe abdominal pain
severe infection or sepsis
severe or worsening diarrhea and age > 70 or immunocompromised
signs of HUS
what are complications of acute diarrhea
reactive arthritis
HUS
post infection IBS?
Precursor to Crohns, UC, celiac?
what are the most common viral agents for infectious diarrhea
norovirus and rotavirus
what is the leading agent causing food born illness
norovirus
what is the transmission of norovirus
fecal-oral route
contaminated foods and water
contaminated surfaces
person-to-person
what is the incubation of norovirus
1-3 days, average 48 hours
what are the symptoms of norovirus
nausea, vomiting, watery diarrhea, abdominal cramping
+/- fever
short duration (hours to 3 days)
what is the most common cause of severe gastroenteritiris in infants and kids worldwide
rotavirus
what is the transmission of rotavirus
fecal-oral route
highly contagious
vaccine available
what is the incubation periods, duration of illness and viral course of rotavirus
incubation: 48 hours
duration of illness: 5-7 days
can shed virus for 10-20 days
what is rotavirus
double stranded RNA virus
causes gut epithelial necrosis
what are the symptoms of rotavirus
profuse watery diarrhea + vomiting in kiddos
more mild in adults
non-bloody diarrhea
fever in abou 50%
what is the treatment of rotavirus
symptomatic + vigorous hydration
anti-diarrheals not recommended in kids under 5
what are the species of shigella
shigella dysenteriae - blood version
shigella flexneri
shigella sonnei
shigella boydii
what is shigella
acid-resistant bacteria - small dose can cause disease
what is the transmission of shigella
fecal-oral route
contaminated food and water
person-to person
often young children at daycare/preschool
what is the incubation and duration of shigella
incubation: 24 hours to 3 days
duration: usually 1 week (self limited)
what are the symptoms of shigella
abrupt onset of watery diarrhea - typically frequent, small volume, bloody stools (NO N/V)
tenesmus, fever, abdominal cramping, lethargy
infects colon so severe dehyration is less likely
what can shigella lead to
HUS - shiga toxin
what is the tx of shigella
abx recommended unless mild disease
fluoroquinolones recommended for adults
azithromycin for those under 18yo
what is the #1 cause of foodborn illness in US
salmonella
what is the transmission of salmonella
fecal contamination of food and water
undercooked food
eggs, milk and other dairy products
contaminated vegetables
contaminated processed foods
person-to-person
transmission from pets
what is salmonella
acid-sensitive - require larger dose for infection
what is the incubation and duration of salmonella
incubation: 1-3 days
duration: usually 2-3 days, no more than 10 days
where does salmonella go into
GI tract through fecal-oral contamination
invades small intestines, moves into regional lymph nodes (peyer’s patches)
what are the symptoms of salmonella
may have gradual or abrupt onset
first nausea, vomiting, fever
later abdominal cramps and diarrhea
progresses to bloody diarrhea in some, but uncommon
symptoms more sever in immunosuppressed, infants, elderly
what is the treatment of salmonella
supportive for most + hydration
abx not routinely indicated
when are abx for salmonella considered
immmunosuppressed, elderly, infants and other medical comorbidities
fluoroquinolones for 3-7 days
what is Campylobacter
acid-sensitive - requires large dose to cause disease
also leading cause of foodborn illnesses
what is responsible for 50% of infections of campylobacter
contaminated poultry
what is the incubation and duration of campylobacter
incubation: avg 3 days
duration: 5-9 days
what are the symptoms of campylobacter
abrupt onset abdominal pain and diarrhea
hematochezia in 15-50%
often have relapse of symptoms within few days of apparent resolution
how is campylobacter diagnosed
microscopy
rapidly motile spiral-shaped organism are characterisitics
what is campylobacter associated with
guillan-carre syndrome (onset 1 week - 2 months post infection_
what is Vibrio
gram negative bacteria
see rapid volume loss, electrylyte abnormalities
what is the incubation and duration of vibrio
incubation: 1-2 days
duration: 3-6 days
what is the transmission of Vibrio parahaemolyticus
salt water reservoirs, especially in summer and fall - can live on plankton
raw and undercooked seafood (oysters(
what are the symptoms of Vibrio parahaemolyticus
Abrupt onset of watery diarrhea +/- blood
abdominal cramps, fever, +/- N/v
what is the treatment of Vibrio parahaemolyticus
supportive + hydration
consider abx if secer or immunocompromised
-doxycycline, fluoroquinolones
what is vibrio cholerae
endemic in asia, africa, central and south america - primarily contaminated water, most US cases are travelers
produces enterotoxin - profuse watery diarrhea (RICE WATER STOOLS)
What are the symtpoms fo vibrio cholerae
asymptomatic to severe diarrhea
fluid loss up to 1L/Hour
rice-water stools
can cause severe dehydration oand electolte disturbances
what is the treatment of vibrio cholerae
rehydration with electrolytes
IV fluids
abx areindicated
-tetracycline, doxy, azithromycin, fluoroquinolones
what is Escherichia coli
E. coli
2 types: enterotoxigenic and enterohemorrhagic
what is the presentation of enterotoxigenic e. coli
infants and children under age 2 in developing countries
traverlers in US cases
few loose stools < 1day to sever watery diarrhea up to 1 week - m/c in resouse limited areas
what is the tx of enterotoxigenic e.coli
rehydration
can consider abx
-azithro or rifaximin
what is enterohemorrhagic e.coli
2/3 of cases are in children
incubation: 3-5 days
duration: few days to 2 weeks
what is the transmission of enterohemorrhagic e.coli
undercooked meat (esp. ground beef)
contaminated vegetables and fruits
contaminated water
via animals
person-to-person
what does enterohemorrhageic e.coli produce
enterotoxin - shiga toxin
bloody diarrhea, TTP, HUS< hemolytic anemia
what are the symptoms of enterohemorrhagic e.coli
watery diarrea for 2-5 days
progresses to bloody diarrhea in 90%
what is the treatment of enterohemorrhagic e.coli
supportive with hydration
no anti-diarrheals
no abx - increased risk of HSU
what foods are prefered by s. aureus
foods high ins urgar, or those with cream, particularly at room temp
what is the duration of illness of s. aureus
24 hours or less - hallmark is rapid recovery
what is clostridium perfringens
commonly found in soil and animal intestinal flora
spore forming bacterium
almost always transmitted via improperly refrigerated cooked mesats
what is the symtpoms of clostridium perfringens
watery diarrhea and crampy abdomonal pain
what is pseudomembranous colitis
classically, pt given abx - abx kills normla flora - c.diff may already be there but able to proliferate and superinfect the colon
- endotoxin release
-watery diarrhea
colon cellular destruction
pt will have severe watery diarrhea, abdominal cramping, fever, leukocytosis
what can pseudomembranous colitis progress into
necrosis and toxic megacolon
colonic performation, sepsis, death
what are high risk groups for c.diff
elderly
debilitated
immunocompromised
pt on multiple abx
abx > 10 days
enteral nutrition
PPI use
undergoing chemotherapy
IBD
how is c.diff transmitted
fecal-oral via spores
primarily person-to-person
what is the presentation of mild and moderate c.diff
greenish, foul smelling watery diarrhea
up to 5-15 BMs per day
WBC > 15,000
what is the presentation of sever or fulminant c. diff
greenish, foul-smelling watery diarrhea
profuse, up to 30 BM per day
WBC > 30,000
albumin < 2.5 g/dL
elevated lactate
increased serum creatinine (usu. greater than 1.5x baseline)
what can fulminant c. diff progress to
respiratory failure
metabolic acidosis
toxic megacolon
colon perforation
death
what is the workup of c. diff
screen with glutamate dehydrogenase (c. diff antigen)
enzyme assay to ID toxins
PCR and ID gene regulating toxin production
what is the treatment of c.diff
PO vancomycin 10-14 days
2nd line: metronidazole
what usually causes cryptosporidium
cryptosporidium hominis
cryptosporidium parvum
much more common in immunocompromised (esp AIDS)
what is the transmutation of cryptosporidium
contaminated food and water - commonly recreational water
person-to-person
animal-to-human
what is the incubation and duration of cryptosporidium
incubation: 1-14 days
duration: typically 5-10 days in immunocompetent
weeks to months in immunocompromised
what are the symptoms of cryptosporidium
watery diarrhea, abdominal cramps, malaise
AIDS pts: frequent foul smelling stools, malabsorption, weight loss
prone to relapse of symtpoms after apparents resolution
how is cryptosporidium diagnosed
negative fecal leukocytes
detection in stool via acid fast stain
what is the treatment of cryptosporidium
supportive + hydration + anti-diarrheals
no ‘best’ drug in literature
recommended: Nitazoxanide
what is giardia lamblia
m/c protozoal infection in the US
travelers diarrhea or contaminated water
-camping and contaminated water
what is the incubation and duration of giardia lamblia
incubation: 1-3 weeks
most recover in 3-4 weeks
what are symtpoms of giardia lamblia
watery diarrhea, occasiaonlly prfuse
flatulence, abdominal cramping, epigastric pain, nausea
some have steatorrhea and weight loss due to malabsorption
how is giardia lamblia diagnosed
+ stool ova and parasite
+/- immunoassay to identify giardia antigens
what is the tx of giardia lamblia
depends on age
tinidazole single dose
nitrazoxanide
metronidazole
