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C. difficile overview Pathogenesis Brief description of various tests Transmission of C. difficile Identifying high-touch surfaces Daily cleaning vs. terminal cleaning Proper use of bleach Brief intro to alternative cleaning products 2 Outline
Historical Perspective Bacillus difficilis (now C. difficile) was cultured from healthy neonates in 1935 In the 1960’s it was noted that patients on antibiotics developed diarrhea “Staphylococcal Colitis” Originally thought to be caused by S. aureus and treated with oral bacitracin Stool cultures routinely ordered for S. aureus Early 1970’s, a new explanation “Clindamycin Colitis” Severe diarrhea, pseudomembrane colitis, and occasional deaths documented in patients on clindamycin
CDI Overview Spore-forming, anaerobic, gram-positive bacterium Causes gastrointestinal infections resulting in diarrhea and colitis – Severity ranges from mild colitis to toxic megacolon and death Leading cause of healthcare-associated infectious diarrhea in US Rivals methicillin-resistant Staphylococcus aureus (MRSA) as the most common organism to cause healthcare-associated infections in US
C. difficile causes about 500,000 illnesses in the United States every year (Kuchn, 2011). In the United States, estimated patients die from the illness each year (Barbut, Jones, & Eckert, 2011). In the general population, one to three percent of adults are colonized with the organism (Barbut et al., 2011). However, about 20 percent of hospitalized adults are C. difficile carriers (LaMont, 2009). 5 Prevalence
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Anaerobic, gram-positive, spore-forming, bacillus Non-toxin producing C. difficile Toxin A (tcdA) Toxin B (tcdB) NAP1/BI/027 (deletion tcdC) Down regulation of toxin production Enhance capability for production of toxin A and B. 7 Strains of C. difficile
8 NAP1/BI/027 (deletion tcdC)
Pathogenesis 9
Two forms of C. difficile VegetativeSpore 10
11 Crypts
12 Normal vs. compromised
13 Pathogenesis cont.
14 Toxin effects on colon
15 Pseudomembranes
Watery diarrhea is the cardinal clinical symptoms Diarrhea can be up to 15 times per day Fever, cramping, abdominal discomfort, and peripheral leukocytosis (cohen, 2010) Colonic ileus or toxic dilatation may present with no or minimal diarrhea. 16 Clinical Symptoms
Culture Cell cytotoxicity neutralization assay Enzyme immunoassays (EIA) C. difficile toxin A (Tcd A) EIA TcdB or TcdA/B EIA, glutamate dehydrogenase (GDH) Nucleic acid amplification tests 17 Methods of testing C. difficile
Target: organism Advantages: High sensitivity (often considered as the gold standard) Disadvantages: Turn-around time >7 days Labor intensive Lacks specificity Isolates must be further tested for the presence of toxins 18 Culture
Functional assay for C. difficile toxin B (TcdB) Advantages: Moderate-to-high sensitivity High specificity Disadvantages: hrs turn-around time Subjective interpretation Labor intensive 19 Cell cytotoxin neutrlization assay
Target: Toxin A detection Advantages: Easy to perform Rapid turn-around time Inexpensive High specificity Disadvantages: Low sensitivity Missess TcdA-/TcdB+ isolates 20 Enzyme immunoassays (EIA) C. difficile toxin A (Tcd A)
Target: Toxin A or B detection Advantages: Easy to perform Rapid turn-around time Inexpensive High specificity Disadvantages: Low sensitivity 21 EIA TcdB or TcdA/B
Method: common antigen detection Advantages: High sensitivity Good screening test Disadvantages: Low specificity Must test further 22 EIA, glutamate dehydrogenase (GDH)
Method: Toxin gene detection Advantages: High sensitivity High specificity Short-turn around time Easy to perform, minimal hands on Disadvantages: Expensive Detection of asymptomatic colonization 23 Nucleic acid amplification tests
GDH Negative Toxin(s) negative Enzyme immunoassay (EIA) GDH and Toxin(s) GDH positive Toxin(s) positive Enzyme immunoassay (EIA) GDH and Toxin(s) GDH positive Toxin(s) negative Enzyme immunoassay (EIA) GDH and Toxin(s 24 Combination method and algorithm Report as positive Report as negative Need further testing
Nucleic acid amplification tests positivenegative Enzyme immunoassay (EIA) GDH and Toxin(s) GDH positiveToxin negative 25 Combination method and algorithm Report as negative Report as positive
46 Consequences of Bad Tests Repeat testing Low sensitivity – False negative patients don’t get treated and spread the organism Low specificity – False positive patients get costly treatments and IC protocols
Practice change Send stool to lab right away or refrigerate If GDH and EIA method are used Test only symptomatic patient (3 loose stools in 24 hours) Test only loose stool (stick or conform) Test only one stool per patient per week Do not test for cure Assess patient for other reasons for the diarrhea
Clinical Practice Guidelines 2010 SHEA and IDSA Summary Test only unformed stool (exception: ileus) Do not perform a test of cure Stool cultures sensitive but not practical except for epidemiological studies EIA is rapid, not very sensitive and is sub-optimal 2 step GDH and EIA is a interim recommendation More data needed on PCR before they can recommend Repeat testing discouraged Cohen, S.H. et al ICHE. 31:
Person to person by swallowing fecal matter. Periods between exposure C. difficile and the occurrences 2- 3 days (cohen, 2010) Culprits in healthcare: Contaminated hands of healthcare worker Electronic rectal thermometers Inadequately cleaned commodes or bedpans Transmission of C. difficile 29
Germs (skin bacteria) Culture plate showing growth of germs 24 hours after a nurse placed her hand on the plate 30
Before entering the room, Clean your hands with: OR Soap and WaterHand Sanitizer 31
After Leaving the room: Wash with soap and water only 32
Acquisition of spores on gloved hands occurred as frequently after contact with environmental surfaces as after contact with skin sites (50% vs 50%) 33 Environmental source
Electronic thermometers Blood pressure cuffs Bedside commodes Stethoscopes 34 Portable equipment Cohen SH, et al. ICHE 2010;31:31:431-55
Omit confusing products 35 Confusing products
House keeping ? Nurses? Central supply? Nobody? 36 Confusion about who cleans what
37 Sufficient contact time is necessary Barbut F, et al. Infect Control Hosp Epidemiol 2009;30:507-14
Stopping the spread: Cleaning and Disinfection Cleaning: Removal of organic matter and visible dirt Disinfection: Killing of microorganisms 38
Reducing contamination of cleaning solution and cleaning tools Laundering microfiber/swiffer after each room cleaning. Replace soiled microfiber/swiffer with clean item each time a bucket or detergent/disinfectant is emptied or replaced. Keeping microfibers/swiffers in solutions do not kill all the bugs, some bugs can grow in the solution. Make sufficient cleaning solution for the day, emptying the solution and drying out the container minimize contamination. Clostridium difficile Excerpt: Guideline for Environmental Infection Control in Health-Care Facilities,
40 High-touch surfaces Huslage K, et al. A quantitative approach to defining high-touch surfaces in hospitals. Infect Control Hosp Epidemiol 2010;31:850-3.
41 Identify frequently touched surfaces
42 Monitor Cleaning
Daily Cleaning Wipe all high-touch surface daily Two wipe system, Clean and Disinfect Minimizing mist and aerosol dispersion 43
44 One bleach wipe multiple time vs. fresh one each time
Terminal/ Dischrage Cleaning Clean all high-touch surfaces and all other area including wall with quaternary solution Then disinfect with bleach wipe or bleach solution. Stay wet for 10 minutes 45
46 Quat vs Bleach
Diluted bleach only stable only for 24 hrs 47 Diluted bleach
One- Step detergent disinfectant Components: Peroxyacetic acid 0.05% Hydrogen peroxide 3.13% Octanoic acid 0.099% Kills C. difficile spores in 10 minutes Effective with 5% organic load (peracetic acid is not affected as much as bleech by organic load) Compatible with materials 48 Peroxyacetic acid/ hydrogen peroxide/ Octanoic acid combination
Precautionary Statement: Danger: Causes irreversible eye damage. Do not get in eyes or on clothing. Wear goggles, face shield, or shielded safety glasses. 49 Peroxyacetic acid/ hydrogen peroxide/ Octanoic acid combination
50 Hydrogen peroxide mist
51 UV light
Identify frequently touched surfaces List them and give copies to housekeeping personnel Identify ownership of equipment cleaning Use EPA registered sporicidal Clean then disinfect even with one-step products Implement daily cleaning 52 Conclusion
53 Questions
Association for Professionals in Infection Control and Epidemiology. (2008). Guide to the Elimination of Clostridium difficile in Healthcare Settings Washington, DC: APIC. Banning, M. (2008, December). Understanding the microbiology, prevalence and pathology of Clostridium difficile. Gastrointestinal Nursing, 6 (10). Retrieved from id=d69405ae-17ec-4e87-b3d7-2fe1cb0adbcb%40sessionmgr12 Barbut, F., Jones, G., & Eckert, C. (2011). Epidemiology and control of Clostridium difficile infections in healthcare settings: an update. Nosocomial and health-related infections. doi: /qco.0b013e e5 Clostridium difficile Excerpt: Guideline for Environmental Infection Control in Health-Care Facilities, (2003) References
Cohen, S. H., Gerding, D. N., Johnson, S., Kelly, C. P., Loo, V. G., McDonald, C.,... Wilcox, M. H. (2010, March 22). Clinical practice guidelines for Clostridium difficle infection in adults: 2010 update by the Society for Healthcare Epidemiology of America (SHEA) and the Infectious Diseases Society of America (IDSA). Infection Control and Hospital Epidemiology, 31 (5). doi: / Gould, C. V., & McDonald, C. (2008, January). Bench-to-bedside review: Clostridium difficile colitis. Critical Care. doi: /cc6207 Huslage K, et al. A quantitative approach to defining high-touch surfaces in hospitals. Infect Control Hosp Epidemiol 2010;31: Kuchn, B. (2011). Scientists seek strategies to prevent Clostridium difficile infections. JAMA, 306 (17), doi: /jama LaMont, J. (2012, June 11). Clinical manifestations and diagnosis of Clostridium difficile infection. UpToDate. Retrieved fromhttp:// clostridium-difficile-infection-in- adults?source=search_result&search=Clinical+manifestations+and+diagnosis+of+Cl ostridium+difficile+infection&selectedTitle=1%7E150http:// clostridium-difficile-infection-in- adults?source=search_result&search=Clinical+manifestations+and+diagnosis+of+Cl ostridium+difficile+infection&selectedTitle=1%7E References