Performance of different culture methods and of a commercial molecular assay for the detection of carbapenemase-producing Enterobacteriaceae in nursing homes and rehabilitation centers.

Over the last several years, carbapenemase-producing Enterobacteriaceae (CPE) have been increasingly detected not only among patients in acute care hospitals, but also in long-term care facilities. In this point prevalence survey, residents from three nursing homes and patients in one rehabilitation center were screened for asymptomatic intestinal carriage of CPE by rectal swabs. The first objective was to evaluate the hypothesis of the establishment of a CPE reservoir in a geriatric/chronic care population. Secondly, we evaluated the comparative performances of different culture methods (chromID(®) CARBA, chromID(®) OXA-48, MacConkey with temocillin/meropenem, ertapenem enrichment broth) and a commercial molecular assay (Check-Direct CPE). From the 257 included residents, only one had evidence for CPE carriage. From the rectal swabs of this resident, an OXA-48-producing Klebsiella pneumoniae could be isolated and was confirmed by a molecular assay both on the strain and on the rectal swab. The specificity of the different culture methods and Check-Direct CPE was at least 97 %. Neither enrichment broth nor prolonged incubation up to 48 h increased the yield of CPE. This point prevalence survey shows a low CPE prevalence of 0.39 %. Larger scaled studies are needed in order to confirm the role of chronic care settings as secondary CPE reservoirs and to adjust the infection control and prevention recommendations.

Carbapenemase producing Enterobacteriaceae in Belgian nursing homes: myth or real danger?

Prevalence of carbapenemase-producing Enterobacteriaceae (CPE) is increasing both in hospitals and in the community. In this point prevalence study, rectal CPE colonization was investigated among 150 nursing home residents. No CPE were detected. Epidemiological data directly linked with CPE colonization in community and nursing home settings are currently lacking. Further research will show whether the preventive measures taken, including a strong focus on standard precautions, a dedicated isolation policy, and antibiotic restriction will retain CPE to invade nursing homes.

Evaluation of Charlson's comorbidity index in elderly living in nursing homes.

The object of this article was to validate the predictive value of Charlson's comorbidity index for the prediction of short-term mortality or morbidity in elderly people. The design was a cohort study comparing survival and hospitalization in institutionalized elderly people with different levels of comorbidity at baseline. The setting was 16 Flemish nursing homes for the elderly. The subjects were 2,727 inhabitants of which full data were available for 2,624. The outcome measures were hazard ratios resulting from Cox regression analysis, comparing 6 months survival in patients with moderate and a high level to low level of comorbidity. Odds ratios resulting from multiple logistic regression analysis comparing the occurrence of at least one hospitalization during the follow-up period in surviving patients of the same groups. Mortality adjusted for age group was significantly increased in patients with a moderate (HR = 2.00) and even more in those with a high level (HR = 3.62) of comorbidity. Hospitalization was more frequent in both groups (OR = 1.54 and 2.19, respectively), with statistical significance only being reached for the highest group. Adjustment for age, gender, mobility status, and disorientation did not change the general picture. Charlson's comorbidity index is a predictor of short-term mortality in institutionalized elderly patients and, to a lesser extend, also of hospitalization. These results support its use as a measure for introducing comorbidity as a covariable in longitudinal studies with a geriatric population.

Consequences of MRSA carriage in nursing home residents.

A prospective cohort study with 1 year follow-up evaluated the relation between MRSA carriage and mortality, likelihood of hospitalization and functional status in residents of a nursing home for the elderly. Included were all 447 residents living in the home in early June 1994. From all patients, swabs were taken from nose, throat and perineum. Additional swabs (sputum, urine or wounds) were taken when indicated. The relative risk (RR) of dying within 6 months in MRSA carriers compared to non-carriers was 2.29 (95% CI = 1.04-5.04). This RR remained stable (1.57-2.40) after adjustment for co-variables using Mantel-Haenszel stratified analysis. After I year, the RR was reduced to 1.30 (95% CI = 0.65-2.58). Univariate survival analysis confirmed a difference in survival between carriers and non-carriers after 6 months (log-rank P = 0.04) and no difference after 1 year. Cox regression analysis resulted in a hazard ratio for dying within 6 months of 1.73 (95% CI = 0.72-4.17). No relation was found between carriage and either likelihood of hospitalization or indicators of functional status. These results are compatible with a possible relation between 6 months mortality and MRSA carriage in nursing home patients. It calls for a large scale, multicentre cohort study in order to either confirm or refute these findings.