Soft tissue and bone MRSA infections

Abstract

A great percentage of orthopaedic patients are elderly people who attend the A/E department usually having sustained a proximal femur fracture after a minor mechanical fall. Many of these patients reside in residential or nursing homes. These patients are generally in poorer health in comparison with those living independently, and are prone to post-operative wound infections. Post-operative wound infections due to methicillin-resistant Staphylococcus aureus (MRSA) continue to be a major concern to clinicians and the public, and to the commissioners and providers of health care. In particular, orthopaedic trauma surgery is a surgical specialty which uses a great variety of implants to treat skeletal injury. Once bacteria, either seeded during the open surgery or carried by the bloodstream, adhere on the implant surface they become very difficult to eradicate. MRSA is implicated in up to 30–50% of all post-operative surgical infections in trauma and orthopaedic surgery. MRSA has been an increasing problem since its isolation in England in 1961. It is easily transmissible from one person to another. MRSA infection can be endogenous (from the patient’s own resident MRSA) or exogenously acquired, by cross-infection from either an asymptomatic carrier or a patient with MRSA infection. MRSA infections result in an increased hospital stay, increased risk for other hospitalised patients and in great financial cost of treatment, due to implementation of further treatment methods, longer need for IV antibiotics, closer patient monitoring and additional surgical intervention. Bloodstream invasion by MRSA can lead to septicaemia, which is associated with 10–20% mortality. The publicity surrounding MRSA has never been greater. The introduction by the Department of Health in the United Kingdom of mandatory surveillance schemes for both MRSA bacteraemia and surgical site infection (SSI) in orthopaedic surgery from 2001 and 2004, respectively, highlights the importance of nosocomial infection. Surveillance of bacteraemia caused by MRSA in the UK has involved collection of data from hospital microbiology laboratories via several mechanisms. These include a voluntary reporting scheme that has been operational in England and Wales since 1989 and mandatory reporting schemes that have been running independently in England, Wales, Scotland and Northern Ireland since 2001. Another surveillance scheme is also available that was created by participating sentinel laboratories that submit isolates for centralised susceptibility testing (Bacteraemia Resistance Surveillance Programme run by the BSAC).