What can healthcare providers do to stop these infections before they start?
Clostridium difficile infection (CDI) due to antimicrobial therapy accounts for 20% to 30% of cases of antibiotic-associated diarrhea.
C. diff is also one of the most common organisms that causes hospital-acquired infections: from 2000 to 2009, the rate of CDI more than doubled and although that rate has leveled, it remains high. The burden of CDI comes with an attributable mortality of 5% to 10%, an increase in hospital stay from 2.8 to 5 days, and a yearly management cost in the United States of $1 billion to $4.9 billion.
For surveillance purposes, CDI can be broken down into standardized definitions to allow for monitoring for a potential outbreak and ensure patient safety that include community-associated, community-onset healthcare facility—associated CDI, and healthcare facility–onset and –associated. Several methods are available to diagnose CDI either alone or in combination, usually by detecting the presence of C. diff toxins in a patient with diarrhea.
Because of the low sensitivity and/or specificity of rapid toxin detection tests, however, such as an enzyme immunoassay (EIA) for toxin A and B, a two-step approach can be utilized using EIA detection of glutamate dehydrogenase with confirmation of positive results by cell cytotoxicity assay, cell culture, or polymerase chain reaction (PCR).
Alternatively, findings from a colonoscopy or histopathology that demonstrate pseudomembranous colitis with the presence of symptoms, usually diarrhea, can help diagnose CDI.
There are several risk factors for CDI: age, duration of hospitalization, and antimicrobial exposure (the most modifiable risk factor). Antibiotics modify the normal bowel flora and allow the C. diff to flourish. During hospitalization, the risk for developing CDI is related to specific classes of antibiotics, such as fluoroquinolones, beta-lactam/beta-lactamase inhibitors, and cephalosporins; the number of different antimicrobials prescribed; and the duration of treatment.
When appropriate, using the minimum number of antibiotics with the narrowest spectrum of activity for the shortest treatment duration may help reduce the rate of CDI. Antibiotic stewardship programs, in collaboration with infection control practices, have been shown to reduce incidence of CDI in hospitals. Different mechanisms can be utilized as part of the stewardship program, and these may include antimicrobial de-escalation based on culture and antibiotic susceptibility, formulary restrictions/prior approval for selected antimicrobials, standard guidelines for treatment and prophylaxis, and development of an antibiogram to guide empiric therapy.
The results of several studies have demonstrated the benefit of appropriate antibiotic utilization on the incidence of CDI as well.
For instance, Valiquette and colleagues implemented guidelines for antibiotic use that incorporated recommendations for antibiotics and shortening antibiotic durations in a tertiary care center in Quebec. As a result, the incidence of CDI decreased by 60% between 2003-2004 and 2005-2006; total and antibiotic consumptions fell as well.
Likewise, Muto and colleagues used a team-based approach toward appropriate antibiotic utilization, combining targeted antimicrobial restriction, education, and expanded infection control measures at the University of Pittsburgh Medical Center. The team observed a decrease in antibiotic-associated CDI of 41%, with the overall rate decreasing to 3/1000 discharges from 7.2/1000 discharges.
On January 1, 2017, new antimicrobial stewardship standards were implemented that mandate the reporting of CDI in every hospital. As previously mentioned, appropriate antibiotic utilization has significantly decreased the rate of hospital-onset CDI. With the current increased incidence of CDI, the reporting rate is an important outcome to monitor.
Indeed, the majority of acute care hospitals are already reporting the incidence of CDI to the Centers for Disease Control and Prevention’s National Healthcare Safety Network as part of the Centers for Medicare & Medicaid Services reporting program.
The best approach to combat CDI is a collaborative one that combines an antimicrobial stewardship program and infection control practices. The identification of patients with suspected CDI should occur rapidly, with contact isolation being implemented immediately. In addition, hand hygiene and disinfection of all surfaces in the patient’s room should be completed to prevention transmission of the infection.
Ultimately, prevention of CDI is key. Efforts should include early identification of patients with CDI, testing of patients who are symptomatic only, and infection-control measures—specifically, contact precautions, environmental cleaning, hand hygiene, and antimicrobial stewardship. We continue to see an increasing incidence of CDI with a high mortality rate. Required reporting will assist in alerting institutions to changes in their CDI rates to help prevent any future outbreaks.
Dr. Amanda Binkley earned her doctor of pharmacy degree at Philadelphia College of Pharmacy. She completed her PGY-1 pharmacy practice residency and PGY-2 infectious diseases residency at the Hospital of the University of Pennsylvania. She is an active member of the Society of Infectious Disease Pharmacists (SIDP).
Dr. Shawn Binkley earned his bachelor of science degree at Pennsylvania State University and his doctor of pharmacy degree at Midwestern University College of Pharmacy—Glendale, Arizona. He completed his PGY-1 pharmacy practice residency and PGY-2 infectious diseases residency at the Hospital of the University of Pennsylvania. He is an active member of SIDP.