THE INCIDENCE OF COLONISATION WITH MRSA IN PATIENTS ADMITTED TO THE TRAUMA WARD WITH A FRACTURED NECK OF FEMUR

Abstract

Background: In recent years an increased trend in MRSA infection has been seen in hospitals and the community, with colonisation rates of between 4 – 17% reported in these patient groups. There is also an association between carriage of Staph. Aureus and staphylococcal surgical wound infection.

In our institution there has been concern regarding MRSA surgical site infection and possible cross contamination of elective and emergency patients. There would be implications for implant related infections if this were to occur. This had prompted the unit to consider adopting a screening programme to identify and treat MRSA carriers. This would aim to minimise risk of post operative infection and cross infection. As little was actually known about the MRSA colonisation rates of admissions to our hospital we undertook the following project to assess the feasibility and effectiveness of implementing such a screening programme.

Aim: To ascertain the incidence of colonisation with MRSA, rate of wound infection and the associated risk factors in patients admitted to the trauma ward with a fractured neck of femur.

Method: A prospective, blinded case series of 100 consecutive patients admitted to the trauma ward with a fractured neck of femur. Three swabs (axilla, nasal and perineum) were taken within 24 hours of admission. Data from each patient was collected to ascertain the presence of risk factors linked to MRSA colonisation and each patient was followed until discharged to assess for surgical site infection.

Results: 304 swabs were taken from 100 patients. Age range 60–97. 26% admitted from institutionalised care and 74% admitted from their own home. Four patients were colonised with MRSA on admission (2 nasal, 2 perineal). An association was seen between patients colonised on admission and long term or recent residence in institutionalised care. One of these patients went on to develop colonisation of the surgical wound however this did not lead to surgical site infection and the patient was successfully treated with MRSA eradication therapy only. In these 4 patients all wounds healed satisfactorily with no evidence of infection.

There were three superficial surgical site infections postoperatively, all in individuals who were clear on their admission screening. Of these two were due to MRSA and one was due to MSSA. There were no cases of deep infection requiring further surgery.

Conclusion:While MRSA continues to be a growing concern we found that, in our hospital, rates of MRSA colonisation and subsequent infection were not high. There were no documented cases of MRSA wound infection in colonised individuals. Given the cost involved in swabbing all patients to detect these low levels of colonisation we do not feel that an expensive screening regimen would be cost effective or justified in our institution.