c dif and vanco Flashcards
c diff is a ____ disease
toxin-mediated intestinal
classification of c diff bacteria
gram (+) anaerobic, spore-forming bacilli
c diff transmission
most common is fecal-oral
c diff is the primary pathogen responsible for _____
antibiotic-associated colitis
why is c diff the most common cause of infectious diarrhea in the healthcare setting
disruption of gut flora due to antibiotics, passing spores to others (exposed)
what is the scary c diff strain called
NAP1/B1/027
what does strain NAP1/B1/027 cause
more severe and more effective transmission, refractory, toxic megacolon, leukemoid reactions (inc WBC), hypoalbuminemia, colectomy, shock, death, complications in elderly due to loss of fluids and electrolytes
symptoms of c diff
profuse, watery, malodorous diarrhea multiple times per day interfering with normal activities, abdominal pain, fever, leukocytosis, hypoalbuminemia, abdominal cramps/pain
c diff endoscopy findings
widely disseminated, punctuate, yellow plaques, ranging from pinhead sized to confluent pseudomembranes
c diff risk factors
exposure to antibiotics (all, but especially clindamycin, cephalosporins, and fluoroquinolones), previous infxn/known exposure, age 65+, weakened immune system, recent hospitalizations, PPIs or H2 blockers
avoid ____ with c diff
antiperistaltics, including narcotics and loperamide
treatment for first episode c diff
pref: fidaxomicin 200 mg po bid x 10d. alt: vancomycin 125 mg po qid x 10d
alternative for first episode c diff if you can’t give fdx or van
metronidazole 500 mg tid x 10-14d
treatment for first recurrence c diff
pref: fidaxomicin 200 mg bid x 10d OR bid x 5d followed by qod x 20d. alt: vanco in a tapered or pulsed regimen OR vanco 125 mg qid x 10d
what is an adjunctive treatment for recurrence of CDI during standard of care
bezlotoxumab
what class is fidaxomicin
macrolide
what is the mechanism of fidaxomicin
inhibits protein synthesis via RNA polymerase
fidaxomicin pk
minimal systemic absorption/nonabsorbed: stays in GI tract
fidaxomicin ade
n/v, abdominal pain. rare: GI hemorrhage, bowel obstruction, anemia, neutropenia
treatment for second or subsequent CDI recurrence
FDX 200 mg BID x 10 or BID x 5 then qod x 20. Vanco tapered and pulsed, or 125 qid x 10 then rifaximin 400 mg tid x 20. fecal microbiota transplant. adjuncts to SOC abx: bezlotoxumab
when is FMT indicated
3 CDI episodes
definition of fulminant CDI
hypotension or shock, ileus, megacolon
treatment for fulminant CDI
vancomycin 500 mg po qid, rectal vancomycin, IV metronidazole 500 mg q8h
stop FMT recipient’s anti-c diff antibiotics at least __ days before
5
bezlotoxumab indication
reduce the recurrence of c diff in patients 18+. NOT for treatment or for monotherapy. must be used with standard of care antibiotics
bezlotoxumab dose
single dose: 10 mg/kg IV given over 1 hour
bezlotoxumab precaution
heart failure
vancomycin structure
cyclic glycopeptide
vancomycin MOA
binds to D-ala D-ala via hydrogen bonds, covers the substrate for cell wall transamidase (transpeptidase) preventing the cross linkage and causing osmotically defective cell walls
vancomycin spectrum
gram + only: MRSA, MSSA, staph, strep, enterococcal, c diff. no gram - activity
vancomycin absorption
not absorbed systemically when given PO. oral vanco is for c diff. IV vanco is for systemic infections
vanco elimination
renal: dose adjustments are necessary
what is the risk with vancomycin
nephrotoxicity: mitigated by exposure AUC: MIC 400-600
vancomycin infusion reaction (“redman’s syndrome)
a histamine-induced reaction when IV administration is too rapid causing hypotension, flushing, erythematous rash
treatment for vancomycin infusion reaction
po antihistamines or iv corticosteroids
other ade for vancomycin
eosinophilia, thrombocytopenia, neutropenia, ototoxicity from 8th cranial nerve damage
