Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Clostridium difficile-Associated Disease (CDAD) Testing Algorithm
Clinical Background
Clostridium difficile is the major cause of antibiotic-associated diarrhea (AAD) and pseudomembranous colitis (PMC).
Epidemiology
- Incidence - 60-65/100,000 in U.S. for clostridial disease (2003)
- Transmission - more than 90% of cases occur after antibiotic administration in patients who are colonized with C. difficile
Organism
- Gram-positive, spore-forming rod
- Obligate anaerobe
- Produces toxins - A, B and binary
- A and B activate cytokines
- Binary toxin is less well understood
- Cultured from the stool of 3% of healthy adults and up to 35% of hospitalized patients
Risk factors
- Previous history of C. difficile disease
- Antimicrobial administration within previous 60 days
- Age >65 years
- Severe underlying illness
- Residence in long-term care center
- Antiulcer medication (proton pump inhibitors)
- Hospital admission
Clinical Presentation
- Mild - diarrhea, abdominal cramping (>3 stools/day)
- Severe - abdominal pain, severe diarrhea, fulminant disease (toxic megacolon)
- Recurrent disease (15-25%)
See Also
Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Clostridium difficile-Associated Disease (CDAD) Testing Algorithm
Diagnosis
Diagnosis
- Indication for testing
- Clinical suspicion based on symptoms and risk factors
- Laboratory testing
- Testing for presence of toxins A and B
- Testing may include stool specimen (culture or cytotoxic assay) or pseudomembrane specimen from colonoscopy
Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Clostridium difficile-Associated Disease (CDAD) Testing Algorithm
Tests generally appear in the order most useful for common clinical situations
| Test name: Clostridium difficile Culture with reflex to Cytotoxin Cell Assay
|
| ARUP #: 0060140 |
| Methodology: Standard reference procedures for anaerobic bacterial culture and identification
|
| Use: Use for epidemiological purposes, such as ribotyping organisms during suspected outbreak |
| Limitations: Does not distinguish toxin-producing strains |
| Follow-up: |
| Test name: Clostridium difficile Cytotoxin Cell Assay
|
| ARUP #: 0065145 |
| Methodology: Cell Culture Assay/Confirmation by Anti-Toxin Neutralization
|
| Use: Use for rapid and clinically relevant diagnosis; test is most specific and highly sensitive |
| Limitations: |
| Follow-up:
|
| Test name: Clostridium difficile Toxins (A & B) by EIA
|
| ARUP #: 0065146 |
| Methodology: Enzyme Immunoassay
|
| Use: Use for rapid and clinically relevant diagnosis; test is less sensitive than culture or cell assay |
| Limitations: |
| Follow-up:
|
References
General References
Loo VG, Poirier L, Miller MA, Oughton M, Libman MD, Michaud S, Bourgault AM, Nguyen T, Frenette C, Kelly M, Vibien A, Brassard P, Fenn S, Dewar K, Hudson TJ, Horn R, Rene P, Monczak Y, Dascal A. A predominantly clonal multi-institutional outbreak of Clostridium difficile-associated diarrhea with high morbidity and mortality. N Engl J Med.
2005;
353(
23):
2442-2449.
McDonald LC, Killgore GE, Thompson A, Owens RC Jr, Kazakova SV, Sambol SP, Johnson S, Gerding DN. An epidemic, toxin gene-variant strain of Clostridium difficile. N Engl J Med.
2005;
353(
23):
2433-2441.
Spigaglia P, Mastrantonio P. Molecular analysis of the pathogenicity locus and polymorphism in the putative negative regulator of toxin production (TcdC) among Clostridium difficile clinical isolates. J Clin Microbiol.
2002;
40(
9):
3470-3475.
Starr J. Clostridium difficile associated diarrhoea: diagnosis and treatment. BMJ.
2005;
331(
7515):
498-501.
Sunenshine RH, McDonald LC. Clostridium difficile-associated disease: new challenges from an established pathogen. Cleve Clin J Med.
2006;
73(
2):
187-197.
Medical Reviewers
Petti, Cathy A., M.D. Medical Director, Infectious Diseases at ARUP Laboratories; Assistant Professor, Pathology and Medicine, University of Utah
Comprehensive Review: November 2007
Last Update: March 2008
