Clinical Microbiology, Infection Prevention Team Up to Fight HAIs

By Kelly M. Pyrek

To understand where clinical microbiology is going in the future, it's helpful to take a quick trip back in history. Years ago, the Study on the Efficacy of Nosocomial Infection Control project established the scientific basis for claims of efficacy of hospital-acquired infection surveillance and control programs, and the importance of clinical microbiology laboratories (CMLs) was emphasized. (Scheckler, 1998).

While the CML is now at the heart of any modern hospital infection prevention and healthcare epidemiology program, it has only been about 15 years since the Society for Healthcare Epidemiology of America (SHEA) established a consensus panel to develop recommendations for optimal infrastructure and essential activities of infection prevention and epidemiology programs in hospitals. In 1996, a SHEA consensus panel developed an assessment of the needs for an effective hospital-based infection control and epidemiology program and identified eight elements: managing critical data and information; setting and recommending policies and procedures; compliance with regulations, guidelines and accreditation requirements; employee health; direct intervention to prevent transmission of infectious diseases; education and training of healthcare workers; personnel resources; and non-personnel resources.

Historically, CMLs have supported infection prevention and healthcare epidemiology programs by extracting data from the analysis of cultures taken from potentially colonized and/or infected patients, with this information having enormous potential for the early detection of healthcare-associated infections (HAIs).

Fast forward to 2011, and CMLs have taken their rightful place in the role call of agents working to reduce and eliminate healthcare-associated infections (HAIs). As Peterson and Brossette (2002) note, "Modern hospital epidemiology only began in the mid-1960s, but since that time the clinical microbiology laboratory has progressively demonstrated the critical roles it can serve for ongoing management and control of healthcare-associated infectious diseases."

Although their opinion is aging, Peterson and Brossette (2002) made an early, eloquent case for the importance of the CML: "The necessary contribution from the laboratory includes surveillance, providing for a systematic observance and measurement of disease, as well as molecular typing of microbial pathogens. Present and future needs for laboratory-based surveillance will require reliable detection of new pathogens that emerge as causes of important health care-associated infections, which implies accurate identification of microbial organisms; recognition of new or emerging antimicrobial agent resistance; and participation in active surveillance for outbreaks, including preparation of specialized media as well as molecular typing. This contribution dictates a strong collaboration between the hospital epidemiologist and the clinical microbiologist, with a consequent positive impact on both the infection control program and the diagnostic laboratory. Such cooperation will be needed as we move to a future where pathogens of concern not only spread within the hospital but have the potential to affect both inpatients and outpatients, healthcare workers, and their households."

This need for collaboration is a central theme within the presentation that Carol A. Rauch, MD, PhD, FCAP, medical director of microbiology for Baystate Health in Springfield, Mass. makes to numerous lab-based groups each year. She points to the statement from Diekema and Pfaller (2007) that, "A good working relationship between clinical laboratory and infection control personnel will greatly facilitate the investigation and control of healthcare-associated infections."

"Pfaller and Diekema emphasized the need for partnerships," Rauch says. "That sounds obvious but it takes time to learn this important lesson and gain perspective through your own experiences that you can share with others in the fight against HAIs."

It can be a tall order to get all of the key stakeholders on the same page, but Rauch says healthcare professionals must do so for the sake of upholding patient safety -- the common, unifying goal of all clinicians. "We are not always aligned to go in the same direction and many departments can sometimes seemingly work at cross purposes, but we must remember that we do the work we do -- HAI monitoring and testing -- to care for our sickest patients. In the clinical microbiology lab, we really are keeping our fingers on the pulse of the data stream, looking for clusters and trends, and educating others about the meaning behind our results -- the more robust these efforts are, the safer our patients will be."

Rauch emphasizes that CMLs play a critical role in the control and elimination of HAIs, and that it's not merely about testing clinical specimens to support the diagnosis and management of infections in patients -- CMLs also play a key role in data collection and analysis (including providing antibiograms and other aggregated data sets), reporting results to the state public health department, and much more. Following Pfaller and Diekema's advice, Rauch says CMLs also inform the infection control committee about feasibility and laboratory resources necessary to support the committee's goals, educate clinicians about the strengths and limitations of tests, and save isolates for possible additional testing. On any given day, CMLs could be managing a surge demand triggered by an outbreak, pandemic or other infectious disease emergency. Clinical microbiologists and other CML professionals must also keep up with the medical and scientific literature, new technology and numerous guidelines whose tenets may sometimes be in conflict with other established guidance, Rauch says. The CML has many masters, Rauch emphasizes, explaining that in addition to working with infection preventionists and epidemiologists, CMLs also support the needs of hospital, regional and state committees, and special project-oriented collaboratives.

Chief among the many duties of the CML is, of course, managing the avalanche of incoming cultures and other tests driven by an increased attention to infectious diseases overall, and to HAIs specifically. Rauch also points to the increased need for surveillance activity by infection preventionists, epidemiologists and clinical microbiologists within the context of the increasing prevalence and complexity of multidrug-resistant organisms (MDROs). "The microorganisms, the tests used to detect them, and the drugs used to fight them, are all tied together in a complicated chess game of sorts. Because of this, we all must learn how to work together because if we don't, we could lose that chess game."

With such demands placed on CMLs, it might be easy to forget about the budgetary and resource constraints they face. As Peterson (2001) notes, in recent years in an effort to contain costs, healthcare institutions have "attempted to restructure, centralize or consolidate laboratory services, including clinical microbiology laboratories, into larger working groups that serve multiple hospitals and retain fewer staff with dedicated microbiology expertise."

Rauch points to current challenges facing CMLs, including personnel shortage at all levels, whether it's bench technologists, laboratory managers or directors, that impact the ability for labs to respond to needs and implement change. Another challenge is the evolving complexity of data coupled with the decreasing availability of information technology (IT) personnel who also understand the laboratory and/or the clinical context involved. Yet another important challenge, Rauch says, is the pressing need to vet the data used when reporting rates of various findings, and CMLs sometimes need to remind their partners that they either can "have it fast, or have it right."

Rauch says she asks infection preventionists, hospital epidemiologists and infectious disease specialists to take into consideration logistical constraints when asking for new tests, and to actually help with the processes. "New tests at the very least require administrative approval, evaluation and documentation of performance characteristics, writing procedures, training staff, educating laboratory users, and programming a variety of computer systems, and all of this takes some time. I like when the lab and clinicians can think through what can be done together, as opposed to the 'why-can't-I-have-this-right-now' dynamic. We also must remind people that test results are not always a yes-or--no situation. All tests have performance characteristics and some are much more reliable than others; they all have different features such as speed, or whether you will have an isolate to look at to compare strains."

Rauch continues, "People often just want the results, but there's a lot behind those results that should be evaluated when interpreting them in the context of an individual patient. This is not unique to infection prevention, as I think everyone in healthcare would benefit from some formal training in basic principles of laboratory testing. People seize upon the results once they are in the computer and take them as reality. To us in the lab, there are patterns within that reality that can make us discount certain findings, or focus on others, or even ask for another sample to test. Working with this data takes experience, and I'd love to see more education about what results actually mean and what to do with t hem. This training is now happening more than in the past, and it is absolutely fundamental for patient care.""

There is escalating complexity of performing the actual testing as well, and Rauch points to examples of recent disclaimers product recalls, backorders, or discontinuance of offering certain tests, sometimes without warning.

Turnaround time may a challenge these days due to the sheer number of tests being required, especially in states that have mandatory screening of pathogens such as methicillin-resistant Staphylococcus aureus (MRSA). "I have an easier situation than others, as Massachusetts has not mandated as much testing as some other states have," Rauch says. "I have been asking my colleagues across the country what their experiences have been like and some of them are testing tens of thousands of samples in a year. If the state mandates this level of testing, I would think that the lab would have the space, the equipment and people to conduct this immense kind of volume. But it goes beyond the question of adequate resourcing; my questions are, will this degree of screening and testing work, and what's the outcome going to be? We are still at a phase where it's not clear what impact this will have on the fight against HAIs. We all want to minimize and eliminate MRSA as a pathogen, but whether or not that is doable or that state-legislated testing mandates are the best way to get there is open for debate right now."

Rauch says it's a matter of choosing to target all infections or specifically targeting MRSA: "There are those who say, 'We'll work on this one problem, we'll learn a lot and we'll use that experience to address other problems' while others say, 'We'll address all problems broadly and in doing so, bring down the MRSA rate significantly.' That's the big divide right now and I don't think anyone has the answer, especially when so many variables come into play."

This dichotomy of strategy, nor the use of lab data as an HAI-prevention strategy, was not lost on Peterson and Brossette (2002) who noted, "The scope of surveillance activities can be either focused (by disease or nursing unit) or comprehensive (system-wide). It can also be passive (detection by fortunate chance observation) or active (planned monitoring of multiple data and infection event sources). The scope of monitoring activities is often confined to surveillance by objective, limited (targeted) monitoring, or hospital-wide surveillance. While the last type of surveillance is preferred, there are often too few resources available to accomplish this ideal. To undertake these differing activities, surveillance is often based on individual patient risk factors, focused on a hospital ward (nursing unit), or based on microbiology laboratory data. All methods have approximately the same sensitivity and specificity; however, surveillance from the laboratory has the advantage of measuring hospital-wide occurrences from a single, central data collection point. While current approaches to using laboratory data are thought to detect only approximately two-thirds of nosocomial infections, some have argued that the use of laboratory data is the most cost-effective surveillance approach."

Rauch says that no matter which side you choose regarding targeted or broad measures, it's critical to not lose sight of the importance of the most basic tenets of infection prevention and control. "To me, no matter what we do or how we do it, hand hygiene is in the middle of all of it and that is a one-size-fits-all solution," she says. "The more you employ basic principles of infection control, the better everything is, and it's the right thing to do to fight HAIs regardless of the expensive molecular tests or other expensive strategies to understand what is happening in your facility. No matter what the role will be for active surveillance, and whichever methods are chosen, it is very clear to me that that some of the basic principles have been overlooked; the good news is that we are coming back around in our thinking." Rauch continues, "I always start analyzing and solving problems with the simple, actionable things first and work up from there. For me, the lessons of many HAIs include attention to basic specimen management, smart use of the laboratory, stuff that we have known for so long but we have stopped paying attention to -- maybe because there are so many more checklists and systems and devices to keep up with. It's not surprising that a specimen sits longer than it needs to. We need to all be aware of the impact that specimen issues can have on the test results and everyone, including lab staff, must pay attention to these issues."

The complexities of testing for MRSA and another daunting foe, Clostridium difficile, require healthcare professionals on both sides of the lab to consider questions relating to whether and how molecular amplification be used; what specimens and body sites should be evaluated; which patients should be tested and under what circumstances; and finally, what should be done with the results, Rauch says. She adds that the intricacies of MRSA and C. difficile testing and reporting can impact data collection on rates.

Again, a partnership between the CML and infection prevention/epidemiology can help smooth out the bumps along the way and add to the body of knowledge needed to combat today's MDROs. "It's important that the key stakeholders understand each other's perspectives," Rauch says," and not just expecting infection preventionists to come into the lab but also asking lab folks to learn about and appreciate the impact of the results they generate. I really enjoy my partnerships with people -- it's been incredibly rewarding. We worked together through the influenza pandemic, and before that, a norovirus outbreak, and it underscored the value of teamwork."

So the value of the CML and its role in the HAI control and elimination process, remains unequivocal. As Peterson and Brossette (2002) say, "Whatever the future holds for healthcare, it is clear that high-quality diagnostic microbiology laboratories are needed to support the infrastructure requirements to assist the healthcare providers for the ongoing management and control of infectious diseases."

References:

Diekema D and Pfaller M. Manual of Clinical Microbiology, ninth edition. ASM Press. 2007.

Pfaller MA and Herwaldt LA. The clinical microbiology laboratory and infection control: Emerging pathogens, antimicrobial resistance, and new technology. Clin Infect Dis. 1997 Oct;25(4):858-870.

Peterson LR, Hamilton JD, Baron EJ, Tompkins LS, J. Miller M, Wilfert CM, Tenover FC, and Thomson RB. Role of clinical microbiology laboratories in the management and control of infectious diseases and the delivery of healthcare. Clin Infect Dis. 32:4, 605-611. 2001.

Peterson LR and Brossette SE. Hunting healthcare-associated infections from the clinical microbiology laboratory: Passive, active, and virtual surveillance. J Clin Microbiol. 40(1):1-4. January 2002.

Pyrek KM. Clinical microbiology and infection prevention are essential partners. Infection Control Today. March 30, 2009. Accessed at: http://www.infectioncontroltoday.com/articles/2009/03/clinical-microbiology-and-infection-prevention-ar.aspx

Rauch CA. The Role of the Clinical Laboratory in Healthcare Healthcare-Associated Infections. PowerPoint presentation, February 2011.

Scheckler WE, Brimhall D, Buck AS, Farr BM, Friedman C, Garibaldi RA, Gross PA, Harris JA, Hierholzer WJ Jr, Martone WJ, McDonald LL, Solomon SL. Requirements for infrastructure and essential activities of infection control and epidemiology in hospitals: A consensus panel report. Society for Healthcare Epidemiology of America. Am J Infect Control. 1998 Feb;26(1):47-60.