Clostridium difficile infection is the leading cause of health care-associated diarrhea, and the bacterium can also be carried asymptomatically. The objective of this study was to identify host and ...bacterial factors associated with health care-associated acquisition of C. difficile infection and colonization.
We conducted a 15-month prospective study in six Canadian hospitals in Quebec and Ontario. Demographic information, known risk factors, potential confounding factors, and weekly stool samples or rectal swabs were collected. Pulsed-field gel electrophoresis (PFGE) was performed on C. difficile isolates to determine the genotype. Levels of serum antibodies against C. difficile toxins A and B were measured.
A total of 4143 patients were included in the study; 117 (2.8%) and 123 (3.0%) had health care-associated C. difficile infection and colonization, respectively. Older age and use of antibiotics and proton-pump inhibitors were significantly associated with health care-associated C. difficile infection. Hospitalization in the previous 2 months; use of chemotherapy, proton-pump inhibitors, and H(2) blockers; and antibodies against toxin B were associated with health care-associated C. difficile colonization. Among patients with health care-associated C. difficile infection and those with colonization, 62.7% and 36.1%, respectively, had the North American PFGE type 1 (NAP1) strain.
In this study, health care-associated C. difficile infection and colonization were differentially associated with defined host and pathogen variables. The NAP1 strain was predominant among patients with C. difficile infection, whereas asymptomatic patients were more likely to be colonized with other strains. (Funded by the Consortium de Recherche sur le Clostridium difficile.).
Background Clostridium difficile (CD) is the leading cause of health care–associated diarrhea and can result in asymptomatic carriage. Rates of asymptomatic CD colonization on hospital admission ...range from 1.4%-21%. The objective of this study was to evaluate host and bacterial factors associated with colonization on admission. Methods The Consortium de recherche québécois sur le Clostridium difficile study provided data for analysis, including demographic information, known risk factors, and potential confounding factors, prospectively collected for 5,232 patients from 6 hospitals in Quebec and Ontario over 15 months from 2006-2007. Stool or rectal swabs were obtained for culture on admission. Pulsed-field gel electrophoresis was performed on the isolates. The presence of antibody against CD toxins A and B was measured. Results There were 212 (4.05%) patients colonized with CD on admission, and 5,020 patients were not colonized with CD. Multivariate logistic regression analysis showed that hospitalization within the last 12 months, use of corticosteroids, prior CD infection, and presence of antibody against toxin B were associated with colonization on admission. Of patients colonized on admission, 79.4% had non-NAP1, non-NAP2 strains. Conclusion There are identifiable risk factors among asymptomatic CD carriers that could serve in their detection and provide a basis for targeted screening.
In an era of rising healthcare expenditures, it is critical to find ways to decrease cost. The objective of this study is to evaluate the number of repeated tests and the associated cost savings in a ...university-affiliated hospital.
The following 7 microbiology analysis were assessed for nonrepeat testing: HCV antibody, HBV core antibody, CMV IgG, rubella IgG, Treponema pallidum antibodies, Clostridioides difficile toxin detection, and vancomycin-resistant enterococci PCR. Presence of a prior positive result leads to the cancellation of subsequent orders.
Percentages of not repeated test ranged from 0.1% to 21.4%. Rubella IgG had the highest proportion of unnecessary repeat testing. Total cost savings were estimated at $33,627 for 2016.
Unnecessary repeated microbiologic test can account for a non-negligible part of total volume test. Use of an automated software to detect unnecessary repeated microbiologic test through laboratory information system can generate important savings.
•Laboratory information systems can detect unnecessary duplicate testing.•Unnecessary repeated testing can represent up to 20% of some microbiology assays.•Significant potential savings can be generated by canceling duplicated tests.•Less frequent but more expensive tests should be aimed in a cost-saving perspective.
Abstract 1140
Poster Board I-162
Cytomegalovirus (CMV) remains the most significant viral pathogen following allogeneic hematopoietic stem cell transplantation. Pre-emptive therapy has now become the ...most commonly used strategy to prevent CMV disease. However, the use of a very effective anti-viral agent could theoretically minimize the risk of disease caused by CMV and other herpesviridae as well as abrogate prospective surveillance after allogeneic transplant. Valacyclovir, the L-valyl ester oral pro-drug of acyclovir, has excellent bioavailability, resulting in high plasma exposures similar to those following IV acyclovir administration. This property confers to valacyclovir antiviral activity against CMV and other herpesviridae. We hypothesized that universal prophylaxis with valacyclovir until day +100 after allogeneic transplant in recipients at high risk of CMV reactivation would lead to a decreased incidence of CMV viremia.
Between 2003 and 2005, we conducted a prospective, randomized study in two allogeneic transplant centers in the Province of Quebec, Canada. Eligibility criteria included therapy with allogeneic blood or marrow transplantation, recipient CMV seropositivity, ability to follow protocol and give informed consent. One group was randomized to receive high dose acyclovir (500 mg/m2 iv TID from day -1 till oral intake was resumed followed by valacyclovir 2000 mg QID until day +100 after transplant (n=32), while the control group was followed using a PCR-based (Cobas system, Amplicor Monitor CMV test, Roche) preemptive approach (n=23). Valacyclovir doses were adjusted according to renal function. In addition, weekly specimens, from before initiation of conditioning regimen until day +100, were also collected in both groups of patients in order to compare incidences of other herpes viruses viremia (HSV, EBV) by real-time PCR. All patients with a positive CMV viremia were immediately treated with ganciclovir 5 mg/kg BID until disappearance of positive signal (minimum of 2 weeks) followed by 2 additional weeks. Recurrences were treated as inititial episodes. Primary end point was incidence of CMV viremia by day +100.
Both groups of patients were similar regarding age, type of transplant (sibling vs unrelated donor), HLA compatibility, conditioning regimen (myeloablative vs reduced intensity), GVHD prophylaxis, graft nature and content and acute or chronic GVHD incidence. Valacyclovir was highly effective to reduce the incidence of CMV viremia. In the Valacyclovir group, CMV viremia occurred in 6 patients (6/31;19%) compared to 12 (12/23;63%) in the control group. Cox regression demonstrates a protective effect with valacyclovir (HR, 0.28; 95% CI: 0.10-0.74; p=0.01). Time to CMV viremia was identical in both groups (day +39 vs +36); however, the median viral load was lower in the valacyclovir group (748 vs 8043) although this difference did not reach statistical difference. Similar to CMV, both incidences of EBV and HSV viremia were significantly lower in the valacyclovir group (EBV: 4% vs 28%, p=0.005; HSV: 4% vs 30%, p=0.002). Day +100 mortality and at last follow-up are similar in both groups. Valacyclovir use was safe and well tolerated by most allogeneic transplant recipients but required frequent dose modification according to creatinine level.
Valacyclovir prophylaxis until day +100 is effective to prevent CMV, HSV and EBV reactivation after allogeneic hematopoietic transplantation. Further studies in larger numbers of patients are needed to precise the optimal use of valacyclovir in this patient population.
Off Label Use: Valacyclovir was used to prevent CMV reactivation following allogeneic transplantation under an experimental protocol approved by our IRB.
A 72 year-old female developed a herpetic esophagitis after 3 d of oral corticotherapy for an acute exacerbation of chronic obstructive pulmonary disease, presenting as odynophagia and total ...dysphagia. Biopsies were taken during a first esophagogastroduodenoscopy (EGD) and the patient was referred to the thoracic surgery service with a presumptive diagnosis of esophageal cancer. A second EGD was planned for dilatation, but by that time the stenosis was completely resolved. The biopsies taken during the first EGD revealed multiple herpetic viral inclusions and ulcerations without any dysplasia or neoplasia. In front of a severe esophageal stenosis, one must still exclude the usual differential diagnosis peptic stenosis and cancer. Visualization of endoscopic lesions can suggest the diagnosis but must be promptly confirmed by biopsy, viral culture or polymerase chain reaction. Although immune systemic effects of corticotherapy are well known and herpetic esophagitis occurs most frequently in immunocompromised individuals, this case emphasizes the importance of clinical awareness concerning short courses of corticotherapy for immunocompetent individuals. This article discusses the reactivation process of herpetic infection in this context and addresses its diagnostic and therapeutic issues.
Congenital rubella syndrome, which is associated with severe malformations, can result from infants exposed in utero to maternal rubella infection. Health care workers and school-based educators are ...targeted for immunization, but evidence is scarce on rubella seronegativity in daycare centre educators who appear to be a high-risk occupational group. The purpose of the study was to generate new evidence on the magnitude of rubella seronegativity and associated risk factors in daycare centre educators.
Sera and questionnaires were collected between October and December 2001 from 481 female educators working in 81 daycare centres in Montréal, Québec. Rubella IgG serology was performed using ELISA.
An overall seronegativity of 10.2% was found. The positive predictive value of previous rubella vaccination with seropositivity was high (92.1%). Ninety-one percent of the women were of childbearing age (= 49 years). Only 1.3% (n = 6) were currently pregnant, none of whom were seronegative. Significant predictors of seronegativity for educator- and daycare-level variables included lack of previous rubella vaccination (OR = 3.60; 95% CI: 1.43, 9.01), not having own children (OR = 3.76; 95% CI: 1.67, 8.55), age per 5-year increment (OR = 0.81; 95% CI: 0.66, 0.99), and increased number of colds in educators in the daycare centre in the last two weeks (OR = 1.15; 95% CI: 1.01, 1.31).
The high proportion of seronegativity, in addition to the potential increased transmission in daycare centres emphasize the need for a review of the rubella vaccination recommendations and health promotion interventions targeted to this occupational group.
Although the use of nonmyeloablative (NMA) hematopoietic stem cell transplantation (HSCT) regimens has expanded in the past decade, little data exist to support antiviral prophylaxis to prevent ...herpes zoster (HZ) in recipients who are seropositive for varicella-zoster virus in this population. The present study examined the clinical features, incidence, and risk factors for HZ in a homogeneous cohort of NMA allogeneic HSCT recipients. We conducted a retrospective cohort study assessing all patients who underwent sibling NMA HSCT at Maisonneuve-Rosemont Hospital (Montreal) between July 2000 and December 2008. All patients received the same conditioning regimen, immunoprophylaxis, and graft-versus-host disease therapy. The diagnosis of HZ was defined clinically. Factors associated with HZ were identified using a Cox proportional hazards model. A total of 179 patients were followed for a median of 33 months (interquartile range, 21-59). HZ developed in 66 patients (37%) at a median of 8.3 months post-HSCT; the incidence rate was 175 cases/1000 person-years. The estimated cumulative HZ incidence was 27% at 1 year, 36% at 2 years, and 44% at 3 years. Thoracic dermatomes were most frequently involved (30%); dissemination occurred in 5 patients. No deaths resulted from HZ, but 23% of patients developed postherpetic neuralgia. In multivariate analysis, reactivation of cytomegalovirus and herpes simplex virus was associated with a reduced likelihood of HZ (hazard ratio, 0.54 and 0.33, respectively). Antiviral prophylaxis or treatment for cytomegalovirus and herpes simplex virus reactivations were protective against HZ. The incidence of HZ in our cohort of NMA HSCT recipients is similar to the incidence reported in HSCT recipients who received a myeloablative conditioning regimen. Given the observed high risk, we conclude that recommendations for antiviral prophylaxis should apply, at least for the first year, to the NMA HSCT population as well.
Day-care centres play a role in the epidemiology of hepatitis A virus (HAV). Up-to-date documentation on its seroprevalence and potential risk factors among day-care educators, who may be at risk for ...significant HAV morbidity, is nevertheless lacking. The availability of a hepatitis A vaccine provides an additional opportunity for prevention in this population. To determine the seroprevalence of previous HAV infection among day-care educators and to identify potential risk factors, we undertook a survey.
Of 167 randomly selected centres, 81 centres participated. Directors and educators completed questionnaires on risk factors. Sera were collected during on-site visits from October through December 2001.
Seroprevalence of previous HAV infection in 492 participating educators was 35.6%. Significant risk factors in multivariate analysis included birth in a high-versus moderate/low-income country (odds ratio OR 20.8; 95% confidence interval CI 9.4-46.0); self-reported HAV vaccination (OR 6.1, CI 2.9-13.0); travel to endemic areas (OR 2.4, CI 1.3-4.2); and age (5-yr OR 1.5, CI 1.3-1.7). When Canadian-born educators were analyzed separately, an association was found between seropositivity and the number of years worked in daycare centres (5-yr OR 1.3, CI 1.0-1.8).
This represents the first study in Canada designed to examine risk factors for previous HAV infection among adult day-care educators. As a group, their risk factors for seropositivity are similar to those in the general population. However, educators born in Canada (a low-endemicity area for hepatitis A) appear to be at additional risk by working in day-care centres. The benefits of HAV screening and routine vaccination of day-care educators need to be examined.
During the past few years, the incidence of invasive group A Streptococcus (GAS) infection has been increasing. However, there are presently no clear recommendations regarding antibiotic prophylaxis ...for close contacts of index patients. The aims of this study were 1) to determine the prevalence of carriage of the same GAS strain as the patient's among contacts of patients with invasive infections and 2) to assess the importance of exposure duration. From March 1995 to March 1996, the authors prospectively included in the study all patients with invasive GAS infection, as defined by the Working Group on Severe Streptococcal Infections, who came to Hôpital Maisonneuve-Rosemont in Montreal, Quebec, Canada. An epidemiologic investigation was systematically carried out for each index case. Contacts were divided into two groups: those who had spent 24 hours or more with the index patient during the week preceding the beginning of his or her illness and those who had spent 12–24 hours with the index patient during that week. Strains of GAS were examined by serotyping (proteins M and T and the presence or absence of the serum opacity factor) and by characterization of streptococcal pyrogenic exotoxins (exotoxins A, B, and C). One hundred and two contacts of 17 index cases with invasive GAS infection were systematically screened. Contacts were considered positive if they carried the same strain of the bacterium and the same streptococcal pyrogenic exotoxin as the index case. Among the contacts who had spent at least 24 hours per week with their respective index cases, 13 out of 48 (27%) were found to be harboring the same serotype of GAS as the index patient (95% confidence interval 14.5–39.5). By comparison, only one of the 54 contacts in the 12- to 24-hour group (1.8%) was found to be carrying the same strain of the bacterium (95% confidence interval 0–5.3). This difference between the two groups was statistically significant (p <0.001). The median age of the positive carriers (10 years) was significantly lower than the median age of the noncarriers (39 years) (p ≦ 0.0005). This study showed that close contacts who had spent 12–24 hours with the index patient were rarely colonized with GAS. If antibiotic prophylaxis against GAS is recommended, it should probably target contacts who spent at least 24 hours with an infected patient during the week preceding illness onset. Am J Epidemiol 1999;149:863–8.
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