Impact of an aggressive infection control strategy on endemic Staphylococcus aureus infection in liver transplant recipients.

BACKGROUND

Methicillin-resistant Staphylococcus aureus has emerged as a leading pathogen in transplant recipients and has become endemic in many institutions where transplantation is performed. The role of active surveillance programs based on the detection of colonization in the prevention of S. aureus infection in liver transplant recipients has not been defined.

METHODS

A total of 47 consecutive patients who underwent liver transplantation during 1996-1999 were compared with 97 patients who received a liver transplant during 2000-2004 after implementation of an intensive intervention program that included use of surveillance cultures to detect nasal and rectal colonization, use of cohorting and contact isolation precautions, and decolonization with intranasal mupirocin therapy.

RESULTS

The rate of new acquisition of S. aureus colonization of nares after transplantation decreased from 45.6% (21 of 46 patients) during the preintervention period to 9.9% (9 of 91 patients) during the postintervention period (P<.001). An increased length of hospital stay (odds ratio, 1.03; 95% confidence interval, 1.01-1.05; P<.002) was associated with new carriage acquisition, and transplantation during the postintervention period (odds ratio, 0.21; 95% confidence interval, 0.08-0.51; P<.001) was independently protective against new carriage. The rate of infection due to S. aureus decreased from 40.4% (19 of 47 patients) during the preintervention period to 4.1% (4 of 97 patients) during the postintervention period (P<.001), and the rate of bacteremia decreased from 25.5% (12 of 47 patients) to 4.1% (4 of 97 patients), respectively (P<.001). Overall, S. aureus infections occurred more frequently among patients with new carriage than among patients who were carriers at the time of transplantation (P<.001) or patients who were noncarriers (P<.001).

CONCLUSIONS

Use of active surveillance cultures to detect colonization and implementation of targeted infection control interventions proved to be effective in curtailing new acquisition of S. aureus colonization and in decreasing the rate of S. aureus infection that was endemic in our population of liver transplant recipients.