Stephanie Smith

A Randomized, Controlled Trial of Doxycycline and Rifampin for Patients with Alzheimer's Disease

Objectives: To assess whether doxycycline and rifampin have a therapeutic role in patients with Alzheimers disease (AD).

Epidemic Diarrhea due to Enterotoxigenic Escherichia coli

BACKGROUND In June 1998, we investigated one of the largest foodborne outbreaks of enterotoxigenic Escherichia coli gastroenteritis reported in the United States. METHODS We conducted cohort studies of 11 catered events to determine risk factors for illness. We used stool cultures, polymerase chain reaction, and serologic tests to determine the etiologic agent, and we conducted an environmental inspection to identify predisposing conditions and practices at the implicated establishment. RESULTS During 5-7 June, the implicated delicatessen catered 539 events attended by >16,000 people. Our epidemiological study of 11 events included a total of 612 attendees. By applying the median prevalence of illness (20%) among events with ill attendees to the total number of events with any ill attendees, we estimate that at least 3300 persons may have developed gastroenteritis during this outbreak. Multiple food items (potato salad, macaroni salad, egg salad, and watermelon) were associated with illness, all of which required extensive handling during preparation. Enterotoxigenic Escherichia coli serotype O6:H16 producing heat-labile and heat-stable toxins was isolated from the stool specimens from 11 patients. Eight patients with positive stool culture results, 11 (58%) of 19 other symptomatic attendees, and 0 (0%) of 17 control subjects had elevated serum antibody titers to E. coli O6 lipopolysaccharide. The delicatessen had inadequate hand-washing supplies, inadequate protection against back siphonage of wastewater in the potable water system, a poorly draining kitchen sink, and improper food storage and transportation practices. CONCLUSIONS In the United States, where enterotoxigenic Escherichia coli is an emerging cause of foodborne disease, enterotoxigenic Escherichia coli should be suspected in outbreaks of gastroenteritis when common bacterial or viral enteric pathogens are not identified.

Molecular epidemiology of vancomycin-resistant enterococcal bacteraemia: results from the Canadian Nosocomial Infection Surveillance Program, 1999–2009

OBJECTIVES Vancomycin-resistant enterococci (VRE) can be associated with serious bacteraemia. The focus of this study was to characterize the molecular epidemiology of VRE from bacteraemia cases that were isolated from 1999 to 2009 as part of Canadian Nosocomial Infection Surveillance Program (CNISP) surveillance activities. METHODS From 1999 to 2009, enterococci were collected from across Canada in accordance with the CNISP VRE surveillance protocol. MICs were determined using broth microdilution. PCR was used to identify vanA, B, C, D, E, G and L genes. Genetic relatedness was examined using multilocus sequence typing (MLST). RESULTS A total of 128 cases of bacteraemia were reported to CNISP from 1999 to 2009. In 2007, a significant increase in bacteraemia rates was observed in western and central Canada. Eighty-one of the 128 bacteraemia isolates were received for further characterization and were identified as Enterococcus faecium. The majority of isolates were from western Canada (60.5%), followed by central (37.0%) and eastern (2.5%) Canada. Susceptibilities were as follows: daptomycin, linezolid, tigecycline and chloramphenicol, 100%; quinupristin/dalfopristin, 96.3%; high-level gentamicin, 71.6%; tetracycline, 50.6%; high-level streptomycin, 44.4%; rifampicin, 21.0%; nitrofurantoin, 11.1%; clindamycin, 8.6%; ciprofloxacin, levofloxacin and moxifloxacin, 1.2%; and ampicillin, 0.0%. vanA contributed to vancomycin resistance in 90.1% of isolates and vanB in 9.9%. A total of 17 sequence types (STs) were observed. Beginning in 2006 there was a shift in ST from ST16, ST17, ST154 and ST80 to ST18, ST412, ST203 and ST584. CONCLUSIONS The increase in bacteraemia observed since 2007 in western and central Canada appears to coincide with the shift of MLST STs. All VRE isolates remained susceptible to daptomycin, linezolid, chloramphenicol and tigecycline.

Chronic Cutaneous Mycobacterium haemophilum Infection Acquired from Coral Injury

A 61-year-old previously healthy man developed chronic dermal granulomata in his right arm after receiving a coral injury in Thailand. After 7 biopsies, infection caused by Mycobacterium haemophilum was diagnosed. This case highlights the difficulty of isolating this fastidious organism in the laboratory and suggests that seawater or coral was the source of the infection.

Nosocomial Gram-negative bacteremia in intensive care: epidemiology, antimicrobial susceptibilities, and outcomes

OBJECTIVES To describe the epidemiology, antimicrobial susceptibilities, treatment, and outcomes of intensive care unit (ICU)-acquired Gram-negative bacteremia. METHODS Patients with ICU-acquired Gram-negative bacteremia from 2004 to 2012 were reviewed retrospectively. Independent predictors of mortality were examined using multivariable Cox regression. RESULTS Seventy-eight cases of ICU-acquired Gram-negative bacteremia occurred in 74 patients. The infection rate was 0.97/1000 patient-days. Mean patient age was 55 years, 62% were male. The most common admission diagnoses were respiratory failure (34%) and sepsis/septic shock (45%). Mortality was 35% at 30 days. The most common source of bacteremia was pneumonia (33%). Of 83 Gram-negative isolates, Escherichia coli (20%) and Pseudomonas aeruginosa (18%) were most common. For aerobic isolates, susceptibilities to ciprofloxacin (61%) and piperacillin/tazobactam (68%) were low. For pseudomonal isolates, susceptibilities to ciprofloxacin (53%), piperacillin/tazobactam (67%), and imipenem (53%) were equally disappointing. Adequate empiric antimicrobial therapy was prescribed in 85% of bacteremia cases. On multivariable analysis, adequate empiric therapy (adjusted hazard ratio (aHR) 0.38, 95% confidence interval (CI) 0.16-0.89), immune suppression (aHR 3.4, 95% CI 1.4-8.3), and coronary artery disease (aHR 4.5, 95% CI 1.7-11.9) were independently associated with 30-day mortality. CONCLUSIONS ICU-acquired Gram-negative bacteremia is associated with high mortality. Resistance to ciprofloxacin, piperacillin/tazobactam, and carbapenems was common. Coronary artery disease, immune suppression, and inadequate empiric antimicrobial therapy were independently associated with increased mortality.

Invasive Sino-Orbital Mycosis in an Aplastic Anemia Patient Caused by Neosartorya laciniosa

ABSTRACT We report the first case of Neosartorya laciniosa invasive sinusitis involving the orbit in an immunocompromised male with aplastic anemia. Treatment included surgical debridement with enucleation of the eye and combination voriconazole and micafungin therapy followed by voriconazole alone. The fungus was identified using sequencing of partial benA and calmodulin genes.

Determinants of Outcome in Hospitalized Patients With Methicillin-Resistant Staphylococcus aureus Bloodstream Infection: Results From National Surveillance in Canada, 2008-2012.

BACKGROUND Bloodstream infection (BSI) due to methicillin-resistant Staphylococcus aureus (MRSA) is associated with considerable morbidity and mortality. OBJECTIVE To determine the incidence of MRSA BSI in Canadian hospitals and to identify variables associated with increased mortality. METHODS Prospective surveillance for MRSA BSI conducted in 53 Canadian hospitals from January 1, 2008, through December 31, 2012. Thirty-day all-cause mortality was determined, and logistic regression analysis was used to identify variables associated with mortality. RESULTS A total of 1,753 patients with MRSA BSI were identified (incidence, 0.45 per 1,000 admissions). The most common sites presumed to be the source of infection were skin/soft tissue (26.6%) and an intravascular catheter (22.0%). The most common spa types causing MRSA BSI were t002 (USA100/800; 55%) and t008 (USA300; 29%). Thirty-day all-cause mortality was 23.8%. Mortality was associated with increasing age (odds ratio, 1.03 per year [95% CI, 1.02-1.04]), the presence of pleuropulmonary infection (2.3 [1.4-3.7]), transfer to an intensive care unit (3.2 [2.1-5.0]), and failure to receive appropriate antimicrobial therapy within 24 hours of MRSA identification (3.2 [2.1-5.0]); a skin/soft-tissue source of BSI was associated with decreased mortality (0.5 [0.3-0.9]). MRSA genotype and reduced susceptibility to vancomycin were not associated with risk of death. CONCLUSIONS This study provides additional insight into the relative impact of various host and microbial factors associated with mortality in patients with MRSA BSI. The results emphasize the importance of ensuring timely receipt of appropriate antimicrobial agents to reduce the risk of an adverse outcome.

Routine Surveillance Versus Independent Assessment by an Outcome Adjudication Committee in Assessing Patients for Sternal Surgical Site Infections After Cardiac Surgery

Based on a cohort of 966 patients, routine surveillance data were not sufficiently accurate for use in clinical trials investigating surgical site infections. Surveillance data can only be used if adequate 90-day follow-up is provided and if cases identified by surveillance are independently reviewed by a blinded outcome adjudication committee.

Blood-Culture-Negative Endocarditis

Blood culture negative endocarditis is defined as definite or probable endocarditis in which three or more aerobic and anaerobic blood cultures collected over 48 h remain negative despite prolonged (greater than 1 week) incubation. Culture negative endocarditis constitutes a significant percentage of all cases of endocarditis in an institution and is a particularly challenging condition for the clinician treating such a patient. An organized approach to diagnosis and treatment is necessary. The most common cause of culture negative endocarditis is prior antibiotic therapy but an increasing number of organisms that cannot be grown in blood cultures given current techniques account for a varying percentage of cases depending on geographic location and laboratory technology. Nucleic acid amplification techniques, immunohistochemistry and transmission electron microscopy on vegetations all have a role in making a diagnosis. In hospital mortality is similar to that of culture positive endocarditis.

Validity of administrative data in identifying complex surgical site infections from a population-based cohort after primary hip and knee arthroplasty in Alberta, Canada

HighlightsComprehensive Infection Prevention and Control prospective surveillance is used at many hospitals to track surgical site infections after hip and knee arthroplasty. ICD‐9 and ICD‐10 codes are used as part of this surveillance.We followed a large population‐based cohort to determine the sensitivity, specificity, and positive and negative predictive values of ICD codes compared to comprehensive Infection Prevention and Control surveillance.The testing characteristics were reasonably accurate and may be useful in hospitals without prospective Infection Prevention and Control surveillance, but the surveillance is still more accurate at detecting surgical site infections. Background Surgical site infections (SSIs) are a substantial burden to healthcare systems in North America. Administrative data is one method though which these may be identified, but the accuracy of using such data is uncertain. Methods We followed a population‐based cohort of patients who received primary hip/knee arthroplasty in Alberta, Canada, for whom a comprehensive Infection Prevention and Control (IPC) prospective surveillance methodology was used to track SSIs. Patients were also followed using International Classification of Diseases, Tenth Revision (ICD‐10) codes. We assessed the sensitivity/specificity and positive/negative predictive values of ICD‐10 codes compared to IPC surveillance. Results Between April 1, 2012, and March 31, 2015, 24,512 people received hip/knee arthroplasty. Of these, 258 (1.05%) had a complex SSI found by IPC surveillance. Sensitivity and specificity of ICD‐10 codes in identifying complex SSIs after hip/knee arthroplasty were 85.3% (95% confidence interval [CI] 80.3%‐89.4%) and 99.5% (95% CI 99.4%‐99.6%), respectively. Positive and negative predictive values were 63.6% (95% CI 58.3%‐68.7%) and 99.8% (95% CI 99.8%‐99.9%), respectively. Discussion Administrative data have reasonable testing characteristics for identifying complex SSIs after arthroplasty. For centers without prospective surveillance programs, this could be useful in identifying hospitals with frequent complex SSIs after arthroplasty. Conclusions A comprehensive IPC surveillance program is superior at detecting SSIs after arthroplasty.