Infectious Diarrhea

Question 1

Diarrhea - the big problem?

Answer 1

Diarrhea and PNA leading causes of death worldwide
Dehydration - that’s what people die of
So Rehydration is the mainstay of tx

Question 2

Cholera (cause)

Answer 2

Toxin (resembles ETEC) binds ganglioside GM1 recpetor and stimulates cAMP –> stimulates CFTR –> secretory diarrhea

Question 3

Cholera (pres/diagnx/treat)

Answer 3

“rice-water” stool, dehydration signs
Non-inflammatory (so no + WBCs or fever), no damage on histol
Treat with ORAL REHYDRATION (salt+sugar+water)

Question 4

ETEC (Entertoxigenic E. Coli)

Answer 4

Most common cause of traveler’s diarrhea
Non-inflammatory
Give supportive tx and ABX

Question 5

Rotavirus

Answer 5

Mostly SPORADIC, infants and young children, fecal oral route
5-8 DAY DURATION
Non-inflammatory
2 EFFECTIVE ORAL VACCINES (live attenuated)

Question 6

Norovirus

Answer 6

Assoc with EPIDEMICS, older kids and adults too, fecal-oral route, contaminated shellfish and water
1-2 DAYS DURATION
Non-inflammatory
Usually self-limiting (no tx)

Question 7

Giardia

Answer 7

Protozoan parasite
fatigue, cramps, FLATULENCE, BLOATING, malodorous fatty stools
Non-inflammatory (parasite in stool)
Supportive tx with antiparasitic

Question 8

Campylobacter jejuni

Answer 8

POULTRY, WATER, UNPASTEURIZED DAIRY
WATERY DIARRHEA (+/- blood)
Inflammatory, fecal leukocytes
Supportive tx with ABX

Question 9

Salmonella Typhi

Answer 9

GNR, Fecal contamination
Pres: TYPHOID FEVER
Inflammatory, diagnx by blood culture
Supportive tx with ABX

Question 10

E.coli O157:H7 (enterohemorrhagic)

(info/cause) binds?

Answer 10

CAUSE OF VAST MAJORITY OF HEMORRHAGIC COLITIS
Bind renal endothelial cells and blocks protein synthesis
Young kids and elderly
Intestines in dairy/beef cattle

Question 11

E.coli O157:H7 (enterohemorrhagic)

pres/diagnx/treat

Answer 11

BLOODY Diarrhea (2-4 days), spectrum of symptoms, TTP (thrombotic thrombocytopenic purpura)
Inflammatory, RBCs IN STOOL but few WBCs, NO FEVER
Give: IVIG, Bactrim, and prevent by cooking food thoroughly

Question 12

Shigella

Answer 12

water contaminated by feces, HIGHEST INFECTIVTY RATE
SEVERE BLOODY OR WATERY diarrhea
Inflammatory
Supportive tx, ABX

Question 13

C. diff (info/cause)

Answer 13

ASSOC with ABX –> disruption of normal microbiota
MAJOR cause of nosocomial diarrhea
Toxin A/B (epidemic strain)
Recurrent dz in 10-15%

Question 14

C. diff (pres/diagnx/treat)

Answer 14

Ranges from mild diarrhea (bloody or watery), may have fever, leukocytosis with severe colitis
Inflammatory
GIVE METRONIDAZOLE first, then VANCOMYCIN
And a fecal transplant to restore normal flora

Question 15

Diarrhea (clinical classification)

Answer 15

3+ loose stools lasting more than one day

Question 16

Diarrhea (causes by %)

Answer 16

30-40% viral

20-30% bacterial/parasitic, 40% unknown

Question 17

FOR REVIEW

Non-inflammatory (pres and causes)

Answer 17

(watery, small bowel)
Cholera
ETEC
Norovirus
Rotavirus
Giardia

Question 18

FOR REVIEW

Inflammatory (pres and causes)

Answer 18

(fever, increased WBC, colon)
Camp. jejuni
Shigella
Salmonella
E. coli O157:H7
C. diff
E. histolytica

Question 19

Enteric fever

Answer 19

(nodes, blood, gallbladder)
Salmonella typhi
S. paratyphi
+/- Yersinia