The first systematic review and meta-analysis of its kind to estimate the prevalence of multidrug-resistant gram-negative bacteria colonization in nursing homes revealed a high colonization rate of 27% among residents, researchers reported.
Sainfer Aliyu, MPhil, MSEd, MHPM, BSN, RN, of Columbia University School of Nursing, and colleagues, said the finding is “concerning” given the amount of interaction and potential opportunities for microbial transmission among patients and health care workers in long-term care facilities such as nursing homes (NHs).
“This study underscores the importance of having strong infection prevention programs in all nursing homes and long-term care facilities,” Linda Greene, RN, MPS, CIC, FAPIC, president of the Association for Professionals in Infection Control and Epidemiology (APIC), said in a press release. “Understanding the dynamics and cause of [multidrug-resistant gram-negative bacteria (MDR-GNB)] transmission is crucial to identifying effective infection control strategies specific to these settings.”
For their study, Aliyu and colleagues reviewed 12 studies performed in the U.S. (n = 7), Germany (n = 2), Korea, Italy and Singapore. Among them, eight were included in the meta-analysis.
The researchers found that MDR-GNB colonization ranged from 11.2% to 59.1% among residents, with Escherichia coli accounting for the largest proportion of isolates. The pooled colonization rate, which represented data from 2,720 participants, was 27% (95% CI, 15.2-44.1). Heterogeneity among the studies was greater than expected (P = .01), the researchers reported.
Two of the studies estimated MDR-GNB infection rates among residents who were admitted to a hospital. The overall rate of infection was 10.9% in one study conducted over 3 months, and 62.7% in the other study conducted over 31 months.
“The researchers suggested that this rate is likely attributable to acquisition and colonization in NHs that present later as clinical infection,” Aliyu and colleagues wrote. “Because infection represents the tip of the iceberg for colonization, these results are consistent with other literature suggesting that rates of MDR-GNB are high in NHs. Hence, when a patient is admitted from a NH to a hospital, surveillance for colonization may be indicated.”
In other results, nine of the 12 studies identified specific risk factors for colonization. These included advanced age, gender, comorbid chronic diseases, a history of recurrent hospitalization, increased interaction with health care professionals, frequent antimicrobial exposure, delayed initiation of effective antibiotic therapy, the presence of medical devices, reduced functional status, advanced dementia, nonambulatory status, fecal incontinence, severe sepsis upon admission and residency in a long-term care facility.
“Identifying which patients are most prone to an increased risk of MDR-GNB will enable infection preventionists to tailor efforts and stem future contaminations,” the researchers said in the release. “The results of our study suggest that there is much more to be done with regard to infection prevention within nursing homes, and that increased measures must be taken with elderly patients in regard to MDR-GNB colonization.” – by Stephanie Viguers
Disclosure: The researchers report no relevant financial disclosures.