Person:

Klompas, Michael

Electronic medical record (EMR) systems are a rich potential source for detailed, timely, and efficient surveillance of large populations. We created the Electronic medical record Support for Public Health (ESP) system to facilitate and demonstrate the potential advantages of harnessing EMRs for public health surveillance. ESP organizes and analyzes EMR data for events of public health interest and transmits electronic case reports or aggregate population summaries to public health agencies as appropriate. It is designed to be compatible with any EMR system and can be customized to different states’ messaging requirements. All ESP code is open source and freely available. ESP currently has modules for notifiable disease, influenza-like illness syndrome, and diabetes surveillance. An intelligent presentation system for ESP called the RiskScape is under development. The RiskScape displays surveillance data in an accessible and intelligible format by automatically mapping results by zip code, stratifying outcomes by demographic and clinical parameters, and enabling users to specify custom queries and stratifications. The goal of RiskScape is to provide public health practitioners with rich, up-to-date views of health measures that facilitate timely identification of health disparities and opportunities for targeted interventions. ESP installations are currently operational in Massachusetts and Ohio, providing live, automated surveillance on over 1 million patients. Additional installations are underway at two more large practices in Massachusetts.

Background: Automatic identification of notifiable diseases from electronic medical records can potentially improve the timeliness and completeness of public health surveillance. We describe the development and implementation of an algorithm for prospective surveillance of patients with acute hepatitis B using electronic medical record data. Methods: Initial algorithms were created by adapting Centers for Disease Control and Prevention diagnostic criteria for acute hepatitis B into electronic terms. The algorithms were tested by applying them to ambulatory electronic medical record data spanning 1990 to May 2006. A physician reviewer classified each case identified as acute or chronic infection. Additional criteria were added to algorithms in serial fashion to improve accuracy. The best algorithm was validated by applying it to prospective electronic medical record data from June 2006 through April 2008. Completeness of case capture was assessed by comparison with state health department records. Findings: A final algorithm including a positive hepatitis B specific test, elevated transaminases and bilirubin, absence of prior positive hepatitis B tests, and absence of an ICD9 code for chronic hepatitis B identified 112/113 patients with acute hepatitis B (sensitivity 97.4%, 95% confidence interval 94–100%; specificity 93.8%, 95% confidence interval 87–100%). Application of this algorithm to prospective electronic medical record data identified 8 cases without false positives. These included 4 patients that had not been reported to the health department. There were no known cases of acute hepatitis B missed by the algorithm. Conclusions: An algorithm using codified electronic medical record data can reliably detect acute hepatitis B. The completeness of public health surveillance may be improved by automatically identifying notifiable diseases from electronic medical record data.

There is a striking paradox in the literature supporting high-profile measures to reduce ventilator-associated pneumonia (VAP): many studies show significant reductions in VAP rates but almost none show any impact on patients' duration of mechanical ventilation, length of stay in the intensive care unit and hospital, or mortality. The paradox is largely attributable to lack of specificity in the VAP definition. The clinical and microbiological criteria for VAP capture a population of patients with an array of conditions that range from serious to benign. Many of the benign events are manifestations of bacterial colonization superimposed upon pulmonary edema, atelectasis, or other non-infectious processes. VAP prevention measures that work by decreasing bacterial colonization preferentially lower the frequency of these mislabelled, more benign events. In addition, misclassification obscures detection of an impact of prevention measures on bona fide pneumonias. Together, these effects create the possibility of the paradox where a prevention measure may have a large impact on VAP rates but minimal impact on patients' outcomes. The paradox makes changes in VAP rates alone an unreliable measure of whether VAP prevention measures are truly beneficial to patients and behooves us to measure their impact on patient outcomes before advocating their adoption.

Background: Obesity was recognized as in independent risk factor for influenza during the 2009 H1N1 influenza pandemic. Objectives: We evaluated the association between body mass index (BMI) and influenza-like illness (ILI) during two non-pandemic influenza seasons (2003–2004 and 2004–2005) and during the spring and fall waves of the 2009 H1N1 pandemic. Methods: Adults with severe (inpatient) and mild (outpatient) ILI were compared to those without ILI using a case-cohort design. The study was nested among those insured by a single health insurance company, receiving care from a large multispecialty practice. Data were collected from insurance claims and the electronic health record. The primary exposure was obesity (BMI ≥ 30·0 kg/m2). Results: Across three seasons, the crude and adjusted ORs for obesity and severe ILI were 1·65 (95% CI 1·31, 2·08) and 1·23 (95% CI 0·97, 1·57), respectively. An association was observed for those aged 20–59 years (adjusted OR 1·92, 95% CI 1·26, 2·90), but not for those 60 and older (adjusted OR 1·08, 95% CI 0·80, 1·46). The adjusted ORs for obesity and severe ILI in 2003–2004, 2004–2005, and during H1N1 were 1·14 (95% CI 0·80, 1·64), 1·24 (95% CI 0·86, 1·79), and 1·76 (95% CI 0·91, 3·42), respectively. Among those with a Charlson Comorbidity Index score of zero, the adjusted ORs for 2003–2004, 2004–2005, and H1N1 were 1·60 (95% CI 0·93, 2·76), 1·43 (95% CI 0·80, 2·56), and 1·90 (95% CI 0·68, 5·27), respectively. Conclusions: Our results suggest a small to moderate association between obesity and hospitalized ILI among adults.

Objective: Hospital-acquired pneumonia remains the most lethal and expensive nosocomial infection worldwide. Optimal therapy remains controversial. We aimed to compare mortality and clinical response outcomes in patients treated with either linezolid or vancomycin. Design: Systematic review and meta-analysis. Data sources PubMed, EMBASE, Cochrane Library, American College of Physicians Journal Club, Evidence-based Medicine BMJ and abstracts from infectious diseases and critical care meetings were searched through April 2013. Eligibility criteria for selecting studies All randomised clinical trials comparing linezolid to vancomycin for hospital-acquired pneumonia. Data extraction Preferred reporting items for systematic reviews and meta-analyses guidelines were followed. One author extracted the data and two authors rechecked and verified all data. Results: Nine randomised trials with a total of 4026 patients were included. The adjusted absolute mortality risk difference (RD) between linezolid and vancomycin was 0.01% (95% CI −2.1% to 2.1%; p=0.992; I2=13.5%. The adjusted absolute clinical response difference was 0.9% (95% CI −1.2% to 3.1%; p=0.409; I2=0%. The risk of both microbiological (RD=5.6%, 95% CI −2.2% to 13.3%; p=0.159; I2=0%) and methicillin-resistant Staphylococcus aureus (RD=6.4%, 95% CI −4.1% to 16.9%; p=0.230; I2=0%) eradication were not different between linezolid and vancomycin. Gastrointestinal side effects were more frequent with linezolid (RD=0.8% (95% CI 0% to 1.5%; p=0.05), but no differences were found with renal failure, thrombocytopenia and drug discontinuation due to adverse events. Our sample size provided 99.9% statistical power to detect differences between drugs regarding clinical response and mortality. Conclusions: Linezolid and vancomycin have similar efficacy and safety profiles. The high statistical power and the near-zero efficacy difference between both antibiotics demonstrates that no drug is superior for the treatment of hospital-acquired pneumonia.

The landmark Study on the Efficacy of Nosocomial Infection Control definitively demonstrated that infection surveillance and control programs prevent hospital-acquired infections. The rise of public reporting, benchmarking, and pay for performance movements, however, has considerably changed the infection surveillance landscape in the 27 years since this study was published. Clinically nuanced surveillance definitions that served the profession well for many years have fallen into disfavor because their complexity and subjectivity allow for conscious and subconscious gaming. These limitations make it very difficult to determine whether changes in surveillance rates represent true changes in disease incidence or artifacts of definition subjectivity, external reporting pressures, and internal biases. Surveillance definitions need to be revised to enhance objectivity and to ensure that they detect clinically meaningful events associated with compromised outcomes. The US Centers for Disease Control and Prevention recently released modified definitions for ventilator-associated events that have the potential to make safety surveillance for ventilated patients more credible and useful once again.

Background. Five neuroinvasive Bacillus cereus infections (4 fatal) occurred in hospitalized patients with acute myelogenous leukemia (AML) during a 9-month period, prompting an investigation by infection control and public health officials. Methods. Medical records of case-patients were reviewed and a matched case-control study was performed. Infection control practices were observed. Multiple environmental, food, and medication samples common to AML patients were cultured. Multilocus sequence typing was performed for case and environmental B cereus isolates. Results. All 5 case-patients received chemotherapy and had early-onset neutropenic fevers that resolved with empiric antibiotics. Fever recurred at a median of 17 days (range, 9–20) with headaches and abrupt neurological deterioration. Case-patients had B cereus identified in central nervous system (CNS) samples by (1) polymerase chain reaction or culture or (2) bacilli seen on CNS pathology stains with high-grade B cereus bacteremia. Two case-patients also had colonic ulcers with abundant bacilli on autopsy. No infection control breaches were observed. On case-control analysis, bananas were the only significant exposure shared by all 5 case-patients (odds ratio, 9.3; P = .04). Five environmental or food isolates tested positive for B cereus, including a homogenized banana peel isolate and the shelf of a kitchen cart where bananas were stored. Multilocus sequence typing confirmed that all case and environmental strains were genetically distinct. Multilocus sequence typing-based phylogenetic analysis revealed that the organisms clustered in 2 separate clades. Conclusions. The investigation of this neuroinvasive B cereus cluster did not identify a single point source but was suggestive of a possible dietary exposure. Our experience underscores the potential virulence of B cereus in immunocompromised hosts.

Staphylococcus intermedius is part of the normal skin and oral flora of dogs. Case reports of human infections are rare, but the true incidence is unknown because the pathogen is frequently misidentified as Staphylococcus aureus. Reported cases range from soft tissue infections to brain abscess. Most reported cases in humans have been related to dog exposure. We report a case of a 73 year old female with S. intermedius surgical wound infection one month following a left elbow total arthroplasty. This is the first reported human case of S. intermedius infection of a mechanical prosthesis. The presumed source of infection was the patient’s dog. The patient was treated with vancomycin, then switched to cefazolin and rifampin once susceptibilities were known. Case reports suggest that patients generally respond well to tailored antibiotics with complete or near-complete recovery. S. intermedius should be included in the differential diagnosis of invasive infection amongst patients with close contact with dogs.