Clostridium difficile

Background

• Most common cause of infectious diarrhea in hospitalized pts
• Use contact isolation if suspect
• Risk factors for pseudomembranous colitis:
  • Recent abx use (any)
  • GI surgery
  • Severe underlying medical illness
  • Chemo
  • Elderly

Diagnosis

History

• Diarrhea that develops during abx use or w/in 2wk of discontinuation
• Recent discharge from hospital
• Profuse watery diarrhea

Exam

• Abdominal pain
• Fever
• Leukocytosis
• +Fecal leukocytes (distinguishes from benign forms of abx-induced diarrhea)

Labs

• C. diff toxin assay
  • Sn 63-94%, Sp 75-100%
• Culture
  • Positve culture only means C. diff present, not necessarily that it is causing disease

Harbor Testing Algorithm

1. Patient with suspected Clostridium difficile associated diarrhea (CDAD)
   1. Low suspicion for CDAD
      1. Send stool for C. diff toxin assay
         1. Positive --> treat (no further testing indicated)
         2. Negative --> do not treat (no further testing indicated)
   2. High suspicion for CDAD
      1. Send stool for C. diff toxin assay AND treat empirically
         1. Positive --> treat (no further testing indicated)
         2. Negative --> Consider discussion with ID (false negative tests may occur); eval for other causes of diarrhea

• Repeat testing
  • Never a need for repeat testing within 7 days of a previous test
  • NO NEED to repeat positive tests as symptoms resolve as a “test of cure”
  • NO NEED to repeat test soon after initial negative test (more likely to be a false positive test than a true positive test)

Treatment

• Mild
  • Either d/c offending abx (if possible) or give metronidazole 500mg PO q6hr x10-14d
• Moderate
  • Metronidazole 500mg PO or IV q6hr x10-14d
• Severe
  • Criteria
    • Age >60yr
    • Temp >38.4 (101)
    • Serum albumin <2.5
    • WBC >15K
    • Pt requires ICU admission
    • Pseudomembranous colitis on endoscopy
  • Tx
    • Vancomycin 125-250mg PO q6hr x10d (IV form is not effective)
    • Add metronidazole 500mg IV q6hr if ileus or pt cannot tolerate PO
• Emergency colectomy should be considered if:
  • WBC >20K
  • Lactate >5
  • Age >75
  • Immunosuppression
  • Toxic megacolon
  • Colonic perforation
  • Multi-organ system failure

Recurrent Infection

1. Occurs <=4 weeks after the completion of therapy
   1. Otherwise consider other (more common) causes
2. Antimicrobial resistance is not clinically problematic, first recurrence treated with the same agent used to treat the initial episode

Antibiotic Sensitivities

Category	Antibiotic	Sensitivity
Penicillins	Penicillin G	X2
	Penicillin V	X1
Anti-Staphylocccal Penicillins	Methicillin	X1
	Nafcillin/Oxacillin	X1
	Cloxacillin/Diclox.	X1
Amino-Penicillins	AMP/Amox	X1
	Amox-Clav	X1
	AMP-Sulb	X2
Anti-Pseudomonal Penicillins	Ticarcillin	X1
	Ticar-Clav	X1
	Pip-Tazo	X1
	Piperacillin	X2
Carbapenems	Doripenem	X2
	Ertapenem	X2
	Imipenem	X2
	Meropenem	X2
	Aztreonam	R
Fluroquinolones	Ciprofloxacin	R
	Ofloxacin	X1
	Pefloxacin	X1
	Levofloxacin	R
	Moxifloxacin	R
	Gemifloxacin	X1
	Gatifloxacin	R
1st G Cephalo	Cefazolin	X1
2nd G. Cephalo	Cefotetan	X1
	Cefoxitin	R
	Cefuroxime	X1
3rd/4th G. Cephalo	Cefotaxime	R
	Cefizoxime	R
	CefTRIAXone	X1
	Ceftaroline	X1
	CefTAZidime	X1
	Cefepime	R
Oral 1st G. Cephalo	Cefadroxil	X1
	Cephalexin	X1
Oral 2nd G. Cephalo	Cefaclor/Loracarbef	X1
	Cefproxil	X1
	Cefuroxime axetil	X1
Oral 3rd G. Cephalo	Cefixime	X1
	Ceftibuten	X1
	Cefpodox/Cefdinir/Cefditoren	X1
Aminoglycosides	Gentamicin	R
	Tobramycin	R
	Amikacin	R
	Chloramphenicol	I
	Clindamycin	X1
Macrolides	Erythromycin	X1
	Azithromycin	X1
	Clarithromycin	X1
Ketolide	Telithromycin	X1
Tetracyclines	Doxycycline	X1
	Minocycline	X1
Glycylcycline	Tigecycline	X1
	Daptomycin	X1
Glyco/Lipoclycopeptides	Vancomycin	S
	Teicoplanin	S
	Telavancin	S
	Fusidic Acid	X1
	Trimethoprim	X1
	TMP-SMX	X1
Urinary Agents	Nitrofurantoin	X1
	Fosfomycin	X1
Other	Rifampin	X1
	Metronidazole	S
	Quinupristin dalfoppristin	I
	Linezolid	I
	Colistimethate	X1

Disposition

• Admit:
  • Severe diarrhea
  • Oupt abx failure
  • Systemic response (fever, leukocytosis, severe abdominal pain)

Source

Tintinalli

See Also

• Diarrhea
• Clostridium