diarrhea presenting with fever

Question 1

Clostritium difficile
NF?
high carriage in??

Answer 1

G+, anaerobic spore-former
NF in 3% gen pop
20-40% carriage in nursing home/hosp. pts

Question 2

C. diff ribotype 078/ST 11 (clade 5)

Answer 2

animal and food assoc–>sev. CDI

Question 3

C. diff toxinotype III strain NAP1/BI/027
virulence??

via what genetic alteration??
associated with ???

Answer 3

hypervirulent strain, CA-CDI
produces 16x more toxin A and 20x more toxin B in vitro than other strains via…
deletion of tcdC gene (depressor of toxin prod.)
use of FQs (FQ resistant)

Question 4

C. diff produces 2 toxins

mechanism??

Answer 4

Toxin A and Toxin B (homology btw them)

both cause cytopathic effect by modifying proteins that regulate actin formation via glycosylation of Rho proteins

Question 5

in response to C. diff toxins: neurons release ?? and LP immune cells releases ??

Answer 5

neurons release substance P
immune cells of LP (i.e. MALT) release inflamm. mediators:
histamine, TNF-a, IL-1

Question 6

C. diff incidence: increasing?

Answer 6

yes by 26%/yr

Question 7

nosocomial C. diff usually trigger by ??

who is at risk more ??

Answer 7

abx therapy (new strains related to inc. FQ use)
oldies >60

Question 8

C. diff reservoir

Answer 8

calves, pigs, 3% of humans (more in hosp pts/nursing home)

Question 9

C. diff age/gender/season assoc.

Answer 9

old age (HCA-CDI)
young adults (CA-CDI)
No gender or season assoc.

Question 10

3 major C. diff risk factors

Answer 10

abx: weeks after tx (takes 3 mos to return to baseline risk)
* hospitalization*: inc. asymptomatic carriage in hosp/nursing home pts

Community-acquired: use of PPIs and H2 blocker use

Question 11

other C. diff risk factors

Answer 11

antineoplastic agents, cathartics, stool softeners, enemas, IBD, antacids, HIV

Question 12

C. diff pathogenesis: abx suppress NF, allowing (previously eaten, colonized) C. diff OG and toxin production
the cytotoxin produces a ??

Answer 12

pseudomembrane: fibrin mesh made of necrotic cells, PMNs, monocytes and RBCs
“white plaque” appearance

Question 13

C. diff cardinal symptom

others

Answer 13

febrile watery diarrhea, 10-15 stools/day!

lower abd. cramps, no cyst. symptoms

Question 14

C. diff causes loss of ?? in stool

Answer 14

serum proteins–>hypoalbuminemia, edema, ascites

Question 15

indicators of severed CDI
do what w. these pts ??
even more worrisome, req. prompt sx consult

Answer 15

fever >38, abd. distension, leukocytosis (>15-20,000)
admit to ICU, sx consult
leuks as high as 50,000 and lactic acidosis

Question 16

?? may proceed C. diff diarrhea

Answer 16

leukocytosis

Question 17

sev. CDI abd. pain caused by

Answer 17

ileus, colonic dilation, toxi megacolon **(get a consult)

Question 18

classic pseudomembronous colitis described as ?? over ??

symptoms??

what is pathognomonic for CDI??

Answer 18

elev. yellow plaques over inflamed mucosa

even more pronounced than sev. colitis

endoscopic appearance

Question 19

C. diff complications

Answer 19

bradycardia, hypotnsn, shock, megacolon, colonic perf

Question 20

C. diff dx: suspect when ??

Answer 20

abx in prev. 2 mos or diarrhea began 72 hr + after hospitalization

Question 21

C. diff dx

Answer 21

stool Cx (sn) (G+ rods with subterminal spores and leukos)
cytotoxin assay (sp) - do both!
EIA and latex agglutination: test for toxin A and B

Question 22

C. diff dx for special occasions, rapid dx

Answer 22

endoscopy

Question 23

in CA-CDI ppl who require hospitalization..

Answer 23

screen for C. diff toxins w. PCR:
tcdA and tcdB (and tcdC: regulatory) -sn and sp!
better than EIA

Question 24

C. diff ddx

Answer 24

UC, chronic IBD, Crohn’s

Question 25

C. diff tx

Answer 25

stop abx that cause it
fluid/e-lyte replacement
abx
probiotic/fecal transplant

Question 26

C. diff tx: abx?

Answer 26

metronidazole (FLD)
vancomycin (cell wall inhib, for sev. disease/metro resistance)
fidaxomicin (macrolide, prot. syn inhib, less effect on NF than vanco)

Question 27

avoid ?? while tx C. diff

why??

Answer 27

antiperistaltic agents (loperamide) 
may hide symptoms and induce toxic megacolon

Question 28

C. diff pts: how many will relapse?

Answer 28

20%

Question 29

C. diff prev.

Answer 29

barrier precautions
isolation
clean with sporicidal agents
wash hands w. soap and water
restrict abx use, esp: 2nd, 3rd gen cephs, clindamycin, FQs (or combo of the 3)
probiotics: Lactobacillus and Saccharomyces boulardii
wash bathroom with bleach