C.diff - Clostridioides Difficile Infection (CDI) - Diagnosis and Management - GrepMed Handbook Clinical Presentation + Progression: • Asymptomatic Colonization (~20% of hospitalized pts on ABx) → Acute Diarrhea (>3 BM/d) ± blood/mucus, Abd pain, Fever, ↑WBC → Pseudomembranous colitis (wall thickening) → Fulminant Colitis (Ileus, Toxic Megacolon, Shock, Perforation) Pathophysiology: Spore ingestion → colonic colonization → proliferation (Abx or chemo) → toxin A/B release → mucosal inflammation and necrosis → pseudomembranes and toxic megacolon Epidemiology: • #1 nosocomial infection up to 10w post-ABx, but can be community-acquired w/o ABx (esp elderly, immunocompromised, IBD) • ↑Risk: clindamycin, quinolones, cephalosporins, carbapenems. Lowest Risk: Tetracyclines Diagnosis: • Stool toxin immunoassay (↑Spec) - Toxin A/B • GDH - Glutamate Dehydrogenase (↑Sens) - produced by all strains, including non-toxigenic • Stool PCR (↑Sens, false ⊕ in colonization, non-toxigenic) - often ordered in reflex if immunoassay equivocal • CT A/P: Assess complications (megacolon, perforation). • KUB ↓↓Sens for complications. • Flex-Sig: If diagnostic uncertainty (Bx) or no improvement with Tx Management (IDSA 2021): • Note: Fidaxomicin is now preferred over vancomycin (limited by $) • d/c offending ABx if possible - otherwise continue Tx for 7d post-Abx • Initial CDI Episode: - Preferred: Fidaxomicin 200 mg PO bid x 10d - Alternative: Vancomycin 125 mg PO qid x 10d • 1st CDI Recurrence • ≥ 2nd CDI Recurrence • Fulminant CDI (Ileus, Megacolon, Shock, Perforation) • Bezlotoxumab 10 mg/kg IV x 1 - Adjunct Tx given along with above regimens for recurrent CDI • Fecal Microbiota Transplant (FMT) - consider if 2 recurrences despite appropriate treatment • Prophylaxis: Vancomycin 125 mg PO qd - If needing ABx or h/o recurrent/severe CDI IDSA 2021 CDI Treatment Guideline: https://doi.org/10.1093/cid/ciab549 #CDI #Cdiff #Clostridioides #Difficile #Clostridium #Infection #diagnosis #management #treatment #infectiousdiseases #IDSA #gastroenterology
