University of Wisconsin
School of Medicine and Public Health

Crnich Research

Christopher Crnich, MD, PhD | Nursing Home Infection Control and Antibiotic Stewardship

Christopher Crnich, MD, PhD, is an infectious disease physician, epidemiologist and health services researcher studying infections and antibiotic resistance in vulnerable older adults.

His research at the University of Wisconsin is primarily focused on design, implementation and evaluation of health system and behavioral interventions to enhance tracking and prevention of infections and antibiotic-resistant organisms in long-term care settings.

He also maintains an active research program at the affiliated William S. Middleton Memorial Veterans Administration (VA) Hospital focused on the prevention and treatment of community- and healthcare-acquired infections.

Dr. Christopher Crnich's Faculty Biography

Collaborations Across Wisconsin and the Nation

Dr. Crnich's research team maintains active collaborations with experts within Wisconsin and across the United States. Specific areas of engagement include:

  • Studies to characterize patterns and determinants of antibiotic decision-making in nursing homes
  • Implementation and evaluation of educational and behavioral interventions for improving the practice of infection control and antibiotic stewardship in nursing homes and hospitals
  • Development and evaluation of telehealth strategies to support the delivery of antibiotic stewardship practices in resource limited settings
  • Studies examining the patterns and determinants of the spread of COVID-19 and other transmissible respiratory viral pathogens in nursing homes
  • Studies examining the patterns and spread of antibiotic-resistant bacteria in different healthcare settings
  • Clinical trials focused on enhancing the treatment of COVID-19 and patients with diabetic foot ulcer infections and other transmissible infections  

Research Team

Health Services Research and Evaluation Scientist I

VA Clinical Research Project Supervisor

Clinical Research Coordinator II

Clinical Research Coordinator I

Nurse Researcher

MPH Student Research Associate

Pharmacy Student Research Associate

Infectious Disease Fellow

Undergraduate Researcher

Campus Collaborators

Active Projects

CDC Nursing Home Public Health Response Network

Given that nursing home residents are older, have multiple comorbidities, live in a congregate setting and have frequent interactions with healthcare workers within the facility as well as have multiple healthcare exposures outside of the facility, nursing home residents are susceptible to many infectious diseases, including respiratory viruses and multidrug-resistant bacteria and fungi, leading to morbidity and mortality for residents, transmission within facilities, and the spread of pathogens in the region. 

CDC seeks to establish a platform that involves a network of nursing homes with pre-positioned study staff and readily available laboratory capacity to perform data collection without impacting clinical care to rapidly characterize infectious diseases, particularly emerging pathogens and SARS-CoV-2 variants of concern, to inform infection prevention and control strategies in nursing homes. Dr. Crnich is a part of a national team conducting this study. 

Supported by the Centers for Disease Control and Prevention

Redesigning Antibiotic Information Systems in Nursing Homes (RAISIN)

Gaps in data availability and subsequent use of prescribing data when available are a significant barrier to effective antibiotic stewardship. WHAIPP plans to collaborate with partners from the University of Wisconsin School of Medicine and Public Health (UWSMPH) on a multi-year collaborative in nursing homes to track prescribing data and coach them to respond to it.

The Redesigning Antibiotic Information Systems In Nursing Homes (RAISIN) Collaborative proposes a phased learning experience for nursing homes to better understand antibiotic tracking and reporting systems and ways to link those systems to quality improvement interventions for improved antibiotic stewardship and better resident outcomes. 

Supported by the Department of Health Services, Wisconsin (06/01/22-07/31/2024) 

Developing a Novel Antibiogram Tool to Improve Empiric Antibiotic Prescribing in Nursing Homes

Empiric antibiotic selection decisions in nursing homes (NHs) are frequently suboptimal, threatening resident safety by increasing risks of adverse drug events and antibiotic resistance. Cumulative susceptibility reports based on patient cultures, known as antibiograms, are increasingly used in NHs to help guide empiric antibiotic decisions. Most NHs collect an insufficient number of cultures to permit development of a facility-specific antibiogram.

In this multi-site study, we propose to develop and evaluate an alternative approach to characterizing local susceptibility patterns in NHs, called a weighted incidence syndromic combined antibiogram (WISCA). This work will also lead to the development of a toolkit to support the implementation and evaluation of WISCAs in NHs. Outcomes from this work will help support future studies examining the effects of WISCAs on antibiotic decisions in NHs. We are optimistic that this and subsequent research in this area will lead to tangible improvements in the quality and safety of antibiotic use in NHs.

Videoconference Antimicrobial Stewardship Team (VAST)

Antimicrobial stewardship guidelines call for a multidisciplinary team with an infectious disease (ID) physician and ID-trained clinical pharmacist as core members. Unfortunately, there are insufficient ID-trained specialists to staff on-site antimicrobial stewardship programs throughout VA.

Using a Type 2 hybrid effectiveness-implementation design, this project implements a multidisciplinary videoconference antimicrobial stewardship team (VAST) in VAMCs using SCAN-ECHO using feedback reports to quantify facility-level antibiotic use and compares clinical effectiveness in sites that implement the VAST alone (VAST-) to sites that implement VAST augmented by facility-level Antibiotic Use Reports (VAST+).

The aims of this study are to:

  1. Identify and test effective strategies for implementing the VAST
  2. Determine the influence of the VAST overall and VAST+ on the care of Veterans with suspected infections
  3. Determine the influence of the VAST overall and VAST+ on antibiotic use at each VAMC

Supported by the VA Office of Research and Development (05/01/22-04/30/2024)  

ACTIV-4a: A Multicenter, Adaptive, Randomized, Controlled Platform Trial of the Safety and Efficacy of Antithrombotic Strategies in Hospitalized Adults with COVID-19

Many patients hospitalized with COVID-19 develop blood clots and signs of coagulation in multiple organs in autopsy findings. These signs of increase coagulation correlate with worse organ failure and mortality. The ACTIV-4a is a multi-center clinical trial looking at agents that decreases coagulation of the blood in patients hospitalized for COVID-19. 

ACTIV-4A aims to determine the effectiveness of antithrombotic strategies for prevention of adverse outcomes and organ failure in COVID-19 positive inpatients. In this adaptive clinical trial, different anti-thrombotic agents will be evaluated including anticoagulation like heparin or anti-platelet agents like P2Y12 inhibitors. ACTIV-4A is a randomized, open label, adaptive platform trial to compare the effectiveness of antithrombotic strategies for prevention of adverse outcomes in COVID-19 positive inpatients. 

Primary Objective:

  1. To determine the most effective antithrombotic strategy for increasing the number of days free of organ support and reducing death. 

Secondary Objectives:

  1. To determine the most effective antithrombotic strategy on the composite endpoint of death, deep vein thrombosis (DVT), pulmonary embolism (PE), myocardial infarction (MI), ischemic stroke, or other systemic arterial thrombosis (AT). 
  2. To assess the safety of antithrombotic strategies through the endpoint of major bleeding as defined by the International Society on Thrombosis and Hemostasis. 
  3. To compare the effect of antithrombotic strategies on the endpoint of all-cause mortality in the study population.

Supported by the National Institutes of Health/National Heart, Lung, and Blood Institute (NHLBI) 

Diagnostic Stewardship as a ‘Nudge’ to Reduce Inappropriate Antibiotic Use for Urinary Tract Infections

Antibiotic-resistant bacteria are estimated by the Centers for Disease Control and Prevention (CDC) to kill over 23,000 Americans yearly. Overuse of antibiotics is a leading cause, and reducing unnecessary antibiotic use is a national priority. A major factor in antibiotic overuse is inappropriate or unnecessary culturing, particularly unnecessary urine culturing that identifies colonization and leads to overdiagnosis of urinary tract infections (UTI).

Diagnostic stewardship is a novel approach to limiting antibiotic use by modifying the ordering, processing, or reporting of a “positive” culture that generally should not be treated. Modifying how tests are ordered, processed, and reported can help improve patient care by using existing technology more effectively. This is a ‘nudge’ approach, developed from psychology and behavioral economics. This work uses the electronic medical record (EMR) in an innovative, mostly behind the scenes fashion to improve appropriateness of ordering and reporting of tests.

The aims of this study are as follows:

  • Aim 1: Define best UTI diagnostic stewardship criteria, based on literature and Delphi method expert panel.
  • Aim 2: Use iterative user-centered design process to develop EMR interface and lab protocols, with clinicians and other stakeholders (nurses, doctors, technicians, and IT representatives).
  • Aim 3: Conduct a pragmatic proof-of-concept hybrid effectiveness implementation study of the UTI diagnostic stewardship interventions in 3 CDC-CREATE Network Healthcare Systems evaluating benefits and any adverse events.

Dr. Crnich is a part of a national team conducting this trial.

Targeted Contact Precautions Use to Prevent MRSA Transmission

Methicillin-resistant Staphylococcus aureus (MRSA) infections are responsible for over 100,000 U.S. hospitalizations each year and have caused more deaths than HIV infection. The major mechanism believed to lead to patient-to-patient transmission in the healthcare setting is contamination of healthcare personnel hands and clothing with MRSA. Healthcare personnel acquire/become contaminated with MRSA from one patient on their hands and clothing and can then transmit the bacteria to other patients. CDC, the VA and other international organizations recommend the use of contact precautions (gloves and gowns) to decrease the transmission of antibiotic-resistant bacteria in acute care settings. Contact precautions decrease the transmission of antibiotic-resistant bacteria because healthcare personnel using gloves and gowns when caring for patients with MRSA discard the contaminated gloves and gowns on room exit, prior to seeing the next patient.

However, contact precautions remain controversial. Some observational studies have shown that there can also be negative aspects of contact precautions, including decreased visits by healthcare personnel, potential psychological side effects such as anxiety and depression, decreased patient satisfaction, and decreased healthcare personnel satisfaction due to the inconvenience of donning and doffing gloves and gowns. Additionally, there are the costs of the gloves and gown.

The aims of this study are to:

  1. Perform a multi-site, geographically diverse cohort study at VA facilities and enroll patients with MRSA colonization or infection to determine the rate of MRSA transmission to healthcare personnel gloves and gowns in ICU and non-ICU settings;
  2. Determine which patient risk factors, including comorbid conditions and severity of illness markers, which patient care interactions and which healthcare personnel types are associated with greater transmission of MRSA; and
  3. Develop a dynamic transmission model to compare the cost-effectiveness of different contact precaution strategies.

Positions Available

The Crnich Nursing Home Infection Control and Antibiotic Stewardship Research Program is always looking for talented and motivated students and post-docs who are interested in projects focused on infection control and antibiotic stewardship in the long-term care setting. We are particularly interested in students who can perform literature reviews, chart reviews, design survey questions, as well as conduct interviews and perform qualitative content analysis.

Prospective students and post-docs are encouraged to email Dr. Crnich at cjc@medicine.wisc.edu even without a specific project in mind. See specifics below.

  • Prospective undergraduate students: include a resume, a list of coursework and grades, and a brief statement of your interests
  • Prospective graduate students: include a CV‚ a list of coursework and grades‚ your GRE scores, and a brief statement of your research interests
  • Prospective residents or fellows: include a CV‚ a list of prior research experience, and a brief statement of your research interests
  • Prospective post-docs: include a CV and a brief statement of your research interests

Funding Support

Dr. Crnich's research is funded by the Agency for Healthcare Research and Quality (AHRQ R01 HS026747 & R01 HS027820), the Centers for Disease Control and Prevention (CDC SHEPheRD Program), the National Institutes of Health (NIH 0T2 HL156812), the Wisconsin Department of Health Services, and the VA Office of Research and Development (CSP #2001; IIR-19-1789; IIR-20-246; IIR-20-252).

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