Methicillin-resistant Staphylococcus aureus (MRSA) remains a significant challenge for human and veterinary health professions especially in the developing nations. Resistance to wide array of antibiotics is a major hurdle in treating MRSA infections including mediastinitis. In present study, therapeutic efficacy of linezolid alone and in combination with rifampicin was evaluated in experimentally induced MRSA mediastinitis in rabbits. Experimental upper median sternotomy was performed on 56 rabbits divided into seven groups. Out of these seven groups, one was taken as uncontaminated control group; one as untreated contaminated group; two groups were given different doses of linezolid, one group was treated with rifampicin alone whereas remaining two groups were given combinational therapy of linezolid and rifampicin. Both 50 mg/kg and 100 mg/kg dose rates of linezolid were found to be effective whereas no added benefit was observed in rabbits given a combination of rifampicin and linezolid. Linezolid can be used in serious MRSA infections especially in those patients not responding to conventional antimicrobial therapy but the selection of correct dose of linezolid is important in each patient.

Key words: Induced mediastinitis, Linezolid, Methicillin-resistant, MRSA, Rabbit, Rifampicin, Staphylococcus aureus