By Gary Evans, Medical Writer
The nation’s long-term care facilities are teeming with multidrug-resistant organisms (MDROs), giving pathogens that can cause virtually untreatable infections access to vulnerable patient populations across the healthcare continuum, epidemiologists warned recently in San Diego at the IDWeek conference.
While infection control and decolonization protocols for long-term care residents are under study, a measure that may have more immediate impact became effective Nov. 28, 2017. The Centers for Medicare & Medicaid Services (CMS) now requires antibiotic stewardship programs in long-term care settings, per a rule adopted last year that included this phased-in requirement.1
The CMS is requiring antibiotic stewardship programs in long-term care that include antibiotic use protocols and some type of drug usage monitoring system. Antibiotic overuse and misuse selects out MDROs by killing off susceptible strains. In addition, antibiotics can wipe out commensal bacteria in the gut, leaving the patient vulnerable to Clostridium difficile infection. Prudent use of antibiotics could reduce the level of such MDROs as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and carbapenem-resistant Enterobacteriaceae (CRE).
The prevalence of MDROs in long-term care is in a large sense the direct result of the sheer volume of antibiotics used in these settings. The CDC estimates that 70% of nursing home residents will receive one or more courses of antibiotics over a given year. As is the case with hospitals, some 40% to 70% of these antibiotics are an inappropriate drug or completely unnecessary.
‘‘Antibiotic use is a strong risk factor for both colonization with MDROs and for acquiring [infections] by MDROs,” said Mary-Claire Roghmann, MD, MS, professor of epidemiology at the University of Maryland School of Medicine. “This has been shown over multiple studies, and we are now entering an era in which CMS regulations will promote antibiotic stewardship in long-term care facilities. Each facility will be asked to develop and implement a protocol by ensuring that residents who require an antibiotic are prescribed the appropriate drug. Part of the goal of this is to reduce the incidence of adverse events including the development of MDROs from unnecessary and inappropriate antibiotic use.”
Phase 3 of the CMS requirements, which include designating an infection preventionist in long-term care, will take effect Nov. 28, 2019.
“Infection prevention coordinators have key expertise and data to inform strategies to improve antibiotic use,” the CDC states.2 “This includes tracking of antibiotic starts, monitoring adherence to evidence-based published criteria during the evaluation and management of treated infections, and reviewing antibiotic resistance patterns in the facility to understand which infections are caused by resistant organisms.”
Given the prevalence of MDROs and the selective pressure exerted by antibiotic use in long-term care, the CMS antibiotic stewardship requirement comes at a critical time.
“The problem is pretty striking,” Roghmann said. “The prevalence of MDROs in long-term care is very high. The most positive message is that CRE is still rare [1% estimated burden] in nursing home residents.”
MDRO transmission routes are more complex in long-term care because of the high prevalence rates and the frequent movement of patients and residents across the healthcare continuum.
“If you think about the constant cycle we have between nursing homes and hospitals, this is, unfortunately, an opportunity to import residents colonized with MDROs into hospitals where there is additional spread,” Roghmann said. “Simulation models show that if you were able to reduce MDROs in nursing homes, that would actually result in a lower prevalence of MDROs in hospitals.”
Unknown Bugs
In addition, most long-term care facilities are largely unaware of how many residents are colonized with one or more MDROs, said Susan Huang, MD, MPH, director of epidemiology and infection prevention at the University of California Irvine School of Medicine.
“The vast majority of multidrug-resistant carriage is unknown in long-term care,” she told IDWeek attendees.
Presenting data from an ongoing study in a network of hospitals, nursing homes, and long-term acute care facilities (LTACs), Huang underscored that shared patients with MDROs move back and forth through all these settings.
“It is well known that the number, spread, and breadth of MDROs continue to rise in healthcare today,” she said. “It begs a very important question about the importance of regional collaboration. If we work together – hospitals, nursing homes, LTACs – is it possible to achieve something much greater than any of us can achieve alone? This idea particularly applies to contagious spread of MDROs.”
For example, an analysis of patient movement in her hospital revealed a wide network of other facilities receiving and transferring patients, Huang said.
“What we see over time is this widening bubble of exposure that we are creating in Southern California and actually up into northern California as people seek healthcare in all sorts of different places,” Huang said.
Similar patterns can be seen whether the pathogen tracked is MRSA, C. diff, or VRE. “You see the exact same thing – this inexorable spread as people need more and more healthcare and get readmitted,” she said.
The ultimate goal of the project is to find effective decolonization protocols for these settings so that transferring patients are less likely to bring MDROs with them. To establish baseline data in the first phase of the study, Huang and colleagues conducted an MDRO prevalence study in 38 facilities, which included 17 hospitals, 18 nursing homes, and 3 LTACs in the San Diego area.
“There is an extensive amount of patient-sharing across this county, across all facilities,” Huang said. “Often, certain facilities are ‘brokers’ between many other facilities, where they share hundreds of patients across multiple hospitals and nursing homes.”
Huang and co-investigators looked for adult patients with MDROs between September 2016 to April 2017, using nares, skin (axilla/groin), and perirectal swabs.3 In nursing homes and LTACs, residents were randomly selected until 50 sets of swabs were obtained. Swabbing in hospitals involved all patients in contact precautions.
The overall prevalence of any MDRO among all patients and residents was 64%, with a range of 44% to 88%. Nursing homes had an 80% MDRO prevalence, with a range of 72% to 86%. LTACs had a 64% prevalence of MDROs, with a range of 54% to 84%.
Even in hospitals, where only patients in isolation were cultured, the investigators found 34% had another MDRO beyond the one that was known. “Overall we found that if you have one [MDRO] you are very likely to have another, and this really bears out no matter what setting we look at,” she said.
Only 25% of culture-positive patients in nursing homes were known by the facility to have an MDRO.
“We found that there is absolutely extensive MDRO carriage throughout the facilities, whether it’s hospitals, nursing homes or LTACs,” she said. “In fact the nursing homes rival the percentage of positives of the hospitalized patients in contact precautions. The vast majority of nursing homes residents who are positive have a status that is completely unknown. In long-term acute care at least seven of 10 patients harbor an MDRO that is unknown to the facility.”
Next Phase: Decolonization
As the next phase in the project, MDRO decolonization protocols are being trialed in the participating facilities.
“The hospitals are decolonizing patients who are in contact precautions for any reason,” Huang said. “We give them daily chlorhexidine bathing or showering and nasal iodophor decolonization for five days.”
The nursing homes and LTACs are using a different decolonization strategy.
“We do universal decolonization in those settings,” Huang said. “We switch out their soap for chlorhexidine whether it is for a bed bath or a shower, and we do nasal iodophor for five days on admission. Then they enter into a facility cycle where Monday through Friday every other week all patients in the facility are decolonized.”
Little CRE was detected and Huang expressed hope that a bug capable of virtual pan-resistance would not get a foothold in the region. However, “in southern California the most rapid rise of CRE is in long-term care,” Huang cautioned.
The findings underscore the premise that facilities must work together in networks, communicating and decolonizing patients if possible.
“We need to think about how we can work together on this idea of contagious spread,” Huang said. “We share a lot of patients. We believe regional cooperation is going to be critical to answering this question about how can we really contain MDROs.”
That said, it will be particularly hard to reduce MDROs in nursing homes because the contact isolation approach used in hospitals is anathema to the goal of resident interaction and mobility in long-term care, Roghmann noted.
“We have to take into account the social and interactive nature of nursing homes,” she said. “We do not keep the residents in a single room. There is communal dining, group recreational activities, physical therapy, and recreation where residents are encouraged to come together. This really complicates the question of how to prevent transmission.”
Nursing homes are typically a mixture to two different populations as defined by duration of stay, she explained.
“The ‘long-stayers’ are people who are there for more than three months – often years,” Roghmann said. “They are primarily there because of cognitive and physical functioning. Then we have the ‘short-stayers.’ Those people are typically there after an acute care hospitalization. They are receiving rehabilitation or skilled nursing care.”
Contrasting the two groups, Roghmann said, the long-stay residents typically have very high levels of MDRO colonization, while the short-stayers have risk factors such as medical devices and wounds that increase their risk of MDRO acquisition.
“It is the mixing within the nursing home that can really lead to spread,” she said.
Similarly, MDRO “source residents” have many risk factors that include medical devices, chronic skin breakdown, problems with immunity, antibiotic use, and a very high dependency on healthcare workers for care. These patients can be colonized with a variety of MDROs at different body sites, she said.
“Then we have ‘recipient’ residents who can then acquire the MDRO, and they have many of the same risk factors,” she said. “This is all occurring through a variety of different transmission pathways that may involve healthcare interactions with geriatric nurse’s assistants, nurses, and physical therapists in an environment that is built to encourage interactions between the residents.”
In addition to – or perhaps because of – these differences between long-term and acute care, there is a dearth of data showing the efficacy of infection control practices in nursing homes. Also, long-term care facilities may have scarce resources to adopt infection control measures.
A Clinical Prediction Rule
Contact precautions often are triggered by MDRO culture positivity in acute care hospitals, but using that approach in long-term care may be both expensive and stigmatizing, she said. Moreover, some people may be only transiently colonized while others have persistent colonization. As an alternative, contact precautions and other interventions could be triggered by the clinical characteristics of the residents, she said.
“For example, we know that people with medical devices are at risk for [MDRO] acquisition and infection,” she said. “We know that skin breakdown makes people at risk for transmitting. Some studies have shown that residents who have the highest dependence on healthcare workers are at increased risk as well.”
The other issue is that MRSA, for example, can colonize multiple body sites and is not necessarily picked up by a nares swab. Swabbing multiple body sites as was done in the Huang study may not be a real-world alternative for nursing homes. Given these issues, it might make more sense to develop a “clinical prediction rule” rather than surveillance cultures for predicting transmission, she said. Such a rule could include clinical variables such as skin breakdown or the presence of devices.
“The prevalence and spread [of MDROs] within nursing homes fuels the spread of MDROs in the healthcare system,” Roghmann said. “Whatever intervention we create it needs to be sustainable for that setting. It needs to work within the resources that nursing homes have and it needs to address some of the cultural biases against the use of infection control. I think that we have taken an enormous step in putting forward antibiotic stewardship in the nursing homes, because it will reduce the spread of [MDROs].”
- CMS. Medicare and Medicaid Programs: Reform of Requirements for Long-Term Care Facilities. Fed Reg Oct. 4, 2016. Available at: http://bit.ly/2dHbDYS.
- CDC. The Core Elements of Antibiotic Stewardship for Nursing Homes. Feb. 28, 2017. Available at: http://bit.ly/2ArDQhL.
- Singh, RD, Jernigan JA, Slayton R, et al. The CDC SHIELD Orange County Project – Baseline Multi Drug-Resistant Organism (MDRO) Prevalence in a Southern California Region. Abstract 1712. IDWeek 2017. Oct. 4-8, 2017. San Diego.
