Diarrhea Flashcards
Most cases of infectious diarrhea are
viral
Most cases of viral diarrhea are
norovirus
Most cases of severe diarrhea are
bacterial
Most cases of bacterial diarrhea are
campylobacter
Def of diarrhea
200g/day of loose water stool; 3x in 24hrs
Patho diarrhea
impaired water absorption or increased water secretion by the bowel
dysentery
infection of the intestinem resulting in severe diarrhea with blood or mucus
Acute v. Persistent v. Chronic
Acute- 14days or less
Persistent- more than 14 days and less than 30 days
Chronic- more than 30 days
Fxn small bowel
- fluid and enzyme secreting organ
- absorbs nutrients
Fxn large bowel
absorb fluid and salt and excrete potassium
Viral causes of diarrhea
norovirus
rotavirus
adenovirus
astrovirus
Bacterial Causes of diarrhea
salmonella campylobacter shigella enterotoxigenic E. coli C. diff
Protozoan causes of diarrhea
cryptosporidium
giardia
cyclospora
Entamoeba
Clinical small bowel diarrhea
watery large volume abdominal cramping bloating gas weight loss
Clinical large bowel diarrhea
frequent, regular small volume painful bowel movement fever blood or mucoid inflammatory and RBC seen on microscopy
Diarrhea of large bowel due to
salmonella shigella campylobacter CMV adenovirus C. diff
Diarrhea of small bowel due to
salmonella e.coli clostridium s. aureus rotavirus norovirus
Petting zoo bacteria
salmonella
Daycare bacteria
shigella
cryptosporidium
giardia
Recent ABX use bacteria
C. diff
When to do stool culture
- more than 6 unformed stools in 24hrs
- severe abdominal pain
- hospitalization
- inflammatory diarrhea (bloody diarrhea, tempt over 101)
- high risk
High risk features that need stool culture
over 70 comorbidities CV disease DM immunocompromised IBD Pregnancy Sx more than 1 week Public health concern
What is fecal lactoferrin
- detect inflammation in the intestines
- detect bacterial infections that cause inflammatory diarrhea
- sensitive and specific
Manage diarrhea
fluid replacement
nutrition replacement- sugar, salt, water
ABX- fluoroquinolones
Antimotility agents- loperamide, pepto-bismol
Probiotics
Clinical norovirus
- very contagious
- acute N/V
- watery diarrhea with abdominal cramps
- sx begin in 12-48hrs
Transmission of norovirus
- close personal contact with infected person
- fecal-oral route with contaminated food
- touching contaminated surfaces
When do norovirus sx end
24-72hrs
MC complication of norovirus
dehydration
Most common nosocomial infections
C. diff
Clinical C. diff
- patient on ABX therapy and sx develop or 5-10days later
- watery diarrhea more than 3 movements in 24hrs
ABX most implicated with C.diff
Fluoroquinolones
Cephalosporins
Penicillins
Risk for C.diff
ABX use
recent hospitalization
advanced age
Patho C.diff
- common in intestine
- grows out of control–> release toxins that damage lining of intestines
Tx c.diff
stop ABX
clean surfaces with soap and water
Vanco or Metronidazole
Where is camphylobacter located?
intestinal tracts of animals, mc in poultry
Incubation period of camphylobacter
3 days
Clinical camphylobacter
abrupt onset of abdominal pain bloody/mucoid diarrhea fever chills aches mimics appendicitis
Tx camphylobacter
healthy ptn: IVF, antiemetic
Severe dz or immunocompromised: Levo, Cipro or azithromycin
Salmonella associated with ingestion of
poultry, milk products and eggs
When does salmonella occur
8-72hrs after ingestion of contaminated food/water
Clinical salmonella
N/V vomiting pea soup diarrhea with a little blood abdominal cramping fever
When does salmonella sx resolve?
fever= 48-72hrs gastroenteritis= 4-10days
TX salmonella
IVF replacement
electrolyte replacement
Severe diz/immuno: Cipro or Levo
Short term carriage
normal shedding of virus after infection; no sx but bacteria shedding
Long term carriage
shedding of bacteria for more than 1 year after infection; no sx but bacteria shedding
Special property of shigella
less susceptible to stomach acid and multiples in small bowel
Transmission of shigella
direct person to person and contaminated food and water
fecal oral in developed countries
Natural reservoir for shigella
human
Where is shigella common
day care centers
Clinical shigella
high fever
small volume diarrhea that is initially watery and then bloody and mucoid
abdominal cramping
tenesmus
Tx shigella
IVF
Electrolyte depletion
Severe dz/immunocompromised: Fluoroquinolone (no Cipro), Azithromycin, Bactrim
How long does shigella last
7 days
Microbiology of botulism
gram + rod shaped anaerobe
Special about botulism spores
heat resistant
How does botulism spread
vascular system
Botulism causes what type of syndrome
neuroparalytic
What is the most potent bacterial toxin
botulism
Botulism spread via
home canning of fruits, veggies, fish
Clinical botulism
sx begin 12-36hrs N/V Diarrhea abdominal pain and cramping dry mouth and sore throat bilateral cranial nerve involvement/palsy
Dx botulism
serum toxin
TX botulism
antitoxins
abx possible- Pen G, Metronidazole
What does cholera cause?
profound fluid and electrolyte loss in stool and rapid progression to hypovolemic shock
Where does cholera affect?
- resource limited areas with inadequate clean water access
- Africa, Asia, Caribbean (MC Haiti)
Transmission of cholera
ingestion of contaminated food and water
Clinical cholera
- incubation 1-2days
- abdominal pain
- rice water stool, fishy smell
- borborygmi
- vomiting
Dx cholera
stool culture and rapid dipstick
Tx cholera
Aggressive volume depletion
ABX for moderate/severe depletion- macrolides, Fluoroquinolones, tetracyclines
Prevention of cholera
- clean water with sanitation
- oral cholera vaccines
MC cause of intestinal entomoeba
E. histolytica
Increased risk of intestinal entomoeba
institutional patients and MSM
Infection of intestinal entomoeba due to
ingestion of amebic cysts via contaminated food and water
Clinical intestinal entomoeba
Onset 1-3days Asymptomatic Mild diarrhea to severe dysentery Abdominal pain Weight loss Fever
Complication of intestinal entomoeba
fulminant colitis with bowel necrosis leading to perforation and peritonitis
Tx intestinal entomoeba
Metronidazole
Tinidazole
Ornidazole
What is the most common parasitic cause of acute foodborne diarrhea in US
Cryptosporidium
Transmission of Cryptosporidium
infected person or animal
fecally contaminated food/water
Tx Cryptosporidium
Antiparasitic meds- Nitazoxanide
What is a common cause of waterborne and foodborne diarrhea in daycare center outbreaks
Giardia
Tx giardia
Metronidazole
Tinidazole
Nitazoxanide
Def travelers diarrhea
diarrhea develops during or within 10 days of returning from travel
MC organism in travelers diarrhea
E. coli
MC organism in travelers diarrhea in SE Asia
Campylobacter
MC organism in travelers diarrhea in Jamaica
Rotavirus
Countries with highest risk of travelers diarrhea
India, Nepal, W./C. Africa
Prevent travelers diarrhea
Bottle only water
Food thoroughly cooked
Pasteurized dairy products
Tx travelers diarrhea
Cipro and Levo
Clinical travelers diarrhea
- patient comes back from trip 5 days ago
- malaise
- anorexia
- abdominal cramps
- watery diarrhea
When to use oral or IV fluids
Oral is best for diarrhea
IVF in severe dehydration- normal saline or ringers lactate (best due to electrolytes) (200mL/kg body weight)
Want fluids with water, salt and sugar
Who shouldn’t take antimotility meds
protozoan and parasitic patients
How does loperamide work
slow down gut motility, decrease number of stool and diarrhea less watery
When to use bile acid sequesters
- patients with persistent diarrhea despite antidiarrheal use
- cholestyramine, colestipole, colesevelum
