C Difficile Tx Flashcards
C diff toxin? Particularly virulent strain? Regulator of toxin expression?
A and B toxins: glycosylation of small GTPases
A – Toxin A (enterotoxin) disrupts colonic mucosal cell adherence to colonic basement membrane and damages villous tips; inflammation leads to fluid secretion
B – Toxin B (cytotoxin) causes depolymerization of actin, resulting in loss of cytoskeletal integrity, apoptosis and death of enterocytes
- *tcdR = toxin regulator
- *NAP-1/027 = particularly virulent!
Most common antimicrobial based treatment associations for C diff? common age? common medical associations?
Antimicrobials – Clindamycin and penicillins / Cephalosporins and flouroquinolones
Age – 65 to 84
Med – IBD, gastric acid suppression (PPIs / H2 block)
**BUT recently CD recurrences were shown NOT to be associated w/ PPIs
CD dx?
EIAs (immunoassay) of Toxins A and B
PCR for toxins A and B
Clinical suspicion
Tx of CD?
First line: Oral Metronidazole
Second line: Oral Vancomycin
1st Recurrence = same thing
2nd recurrence = oral vanco, extended administration
– Complicated disease: high dose oral vanc, IV metronidazole
– Ileus, abdominal distention: rectal vancomycin enema
Metronidazole in pregnancy / long term use
– Crosses placenta / expressed in breast milk! (facial abnormalities / candida colonization)
– Long term use = peripheral parasthesis
Fidaxomicin
Special??
Systemization?
MOA: macrolide antibiotic (23s ribosomal subunit?) = xRNA polymerase
**LACK OF CROSS RESISTANCE W/ other antimicrobials used for CD
**MINIMAL SYSTEMIZATION – similar AEs to vancomycin (nausea, vomiting, GI bleed)
**superior clinical response w/ lower incidence compared to vanc!
requirements pre and post-fecal transplant for recipient? for donor?
Recipient:
- stop antibiotics 2-3 days prior, colonoscopy like prep,
- loperamide after transplant
Donor:
- screen for hepatitis, HIV, syphilis
- stop antimicrobials
- stool softener
- *instilled by colonoscopy / NG tube to lower GI
- *NO adverse effects reported!
