Clostridium difficile Infections in a Canadian Tertiary Care Hospital before and during a Regional Epidemic Associated with the BI/NAP1/027 Strain

Abstract

Since 2002, an epidemic of Clostridium difficile infections has occurred in southern Quebec, Canada. At Hôpital Maisonneuve-Rosemont, Montreal, Quebec, Canada, the incidence of C. difficile infections increased from 11/1,000 admissions (1999 to 2002) to 27/1,000 admissions (2003 to 2005). We compared the exposures and outcomes for patients infected with strains with different ribopatterns isolated before (n ‫؍‬ 55) and during (n ‫؍‬ 175) the epidemic, as well as the in vitro activities of antibiotics against those isolates. During the preepidemic period, 46 isolates (84%) were of ribotype 001, 1 was of ribotype 027, and 8 were of other ribopattern types. During the epidemic period, ribotype 027 strains accounted for 140 (80%) isolates; 26 (15%) were of ribotype 001, and 7 were of other ribopattern types. Ribotype 027 strains were highly resistant to fluoroquinolones (FQs) but were susceptible to clindamycin. A pattern of prior specific antibiotic exposure that selected for antibiotic-resistant ribotype C. difficile infections was observed for FQs (ribotype 027) and clindamycin (ribotype 001). The rate of mortality was higher among older patients, those with a high Charlson comorbidity index, and those with longer previous hospitalizations. By multivariate analysis, patients infected with ribotype 027 were twice as likely to die within 30 days of diagnosis than patients infected with other ribotypes (adjusted odds ratio, 2.06; 95% confidence interval, 1.00 to 4.22). The observations from this study support the notion that continued selective antibiotic pressure resulted in the superimposition of the hypertoxigenic ribotype 027 clone on top of the prior dominant ribotype 001 clone in a setting of preexisting high endemicity, thus leading to the high rates of morbidity and mortality seen in the Quebec outbreak. Stringent antibiotic stewardship measures, combined with aggressive infection control, are required to curtail the epidemic of C. difficile infections.

Clinical and Laboratory Characteristics of Clostridium difficile Infection in Patients with Discordant Diagnostic Test Results

“…The spectrum of disease can range from uncomplicated diarrhea to pseudomembranous colitis, toxic megacolon, sepsis with associated organ failure, and even death. North American hospitals began to experience an increased incidence of a particularly virulent strain of C. difficile in the early part of the decade, characterized by recurrent infection and increased mortality, especially in the elderly (3,8,11,14,20).The increase in the incidence of C. difficile infection (CDI) has been attributed in part to the emergence of a predominant strain, known as North American pulsed-field type 1 (NAP1), of ribotype 027 and group BI. The characteristics of the NAP1 strain include fluoroquinolone resistance, production of binary toxin in addition to toxins A and B, and various polymorphisms in the tcdC gene (13).…”

“…The spectrum of disease can range from uncomplicated diarrhea to pseudomembranous colitis, toxic megacolon, sepsis with associated organ failure, and even death. North American hospitals began to experience an increased incidence of a particularly virulent strain of C. difficile in the early part of the decade, characterized by recurrent infection and increased mortality, especially in the elderly (3,8,11,14,20).…”

Evaluation of the Cepheid Xpert Clostridium difficile Epi Assay for Diagnosis of Clostridium difficile Infection and Typing of the NAP1 Strain at a Cancer Hospital

“…The 18-bp and 1-bp deletions are proposed to result in a truncated TcdC protein, with loss of negative regulatory function that results in higher toxin production (22,31). Although a recent report failed to detect a statistically significant correlation between disease severity and the NAP1 strain (30), others, including a recent report of a phase 3 clinical trial of fidaxomicin, support the increased virulence of the NAP1 strain (6,9,14).…”

Comparison of two types of matrix-assisted laser desorption/ionization time-of-flight mass spectrometer for the identification and typing of Clostridium difficile

“…Among obligate anaerobes, Clostridium difficile is frequently isolated and the number of infected patients has been increasing every year. Indeed, in 2002, a hypervirulent C. difficile strain (B1/NAP1/027 type) was reported in several countries (Labbé et al, 2008;McFarland, 2008) and is of significant clinical concern for potential outbreaks. Martiny et al (2012) conducted a comparative investigation to examine the accuracy of identifying clinical isolates using three softwares with two types of MALDI-TOF MS and obtained satisfactory results with both types.…”