[Generalized or targeted screening for carriage of MRSA on admission to a geriatric hospital]

To confirm previously risk factors for MRSA carriage in our geriatric patient population and to suggest a simplified risk score with a combination of these risk factors, to test the Novel Score and to check if a targeted MRSA screening on admission is possible to reduce the screening workload and cost.

a prospective in-hospital cohort study.

1125 geriatric patients were screened for MRSA carriage within 24 hours after admission to a geriatric hospital.

Risk factors, based on recently published risk scores (Preop Score and Ger Score) were determined.

Prevalence of MRSA carriage was 8.44%. In a multivariate analysis age > or = 87 year (OR 1,864; 95% CI 1,145-3,035), presence of a long-term catheter (OR 2,813; 95% CI 1,562-5,065) and prior carriage of MRSA (OR 13,25; 95% CI 8,007-21,926) remained predictors of MRSA carriage. The Novel Score (cut-off > or = 1) had a sensitivity of 73.7%, a specificity of 64%, PPV 15.9%, NPV 96.3% and AUC of 0.688. The Novel Score allows reduction of the screening load by 57.2%, but misses 26% of positive cases. 16% of MRSA carriers develop an infection that needs to be treated with vancomycin.

With targeted MRSA screening on admission based on a risk score a substantial reduction of workload and costs is possible compared to generalized screening for MRSA. Because MRSA carriers can be missed with a risk score, the epidemiological context and the risk of transmission and infection with MRSA must be taken in to account when introducing a targeted screening.