Does MRSA Affect Clinical Outcomes?

Objective To compare the outcomes of patients with methicillin resistant Staphylococcus aureus (MRSA) infections to patients without MRSA.    Methods This is a post hoc analysis of two prospective randomized clinical trials (RCT) to evaluate the effectiveness of negative pressure wound therapy with and without irrigation in moderate and severe foot infections as defined by the IDSA. The results of the RCTs were negative.   Two hundred-forty_patients admitted to a single hospital were enrolled. Microbiological data was collected with demographics and outcomes. Groups compared using t test and chi square. Results Twenty-nine (12.1%) people had infections with MRSA on their index hospitalization (3.4% bone only, 62.1% tissue only, 34.5% bone and tissue). At baseline, there were no differences between groups. Patients with MRSA had significantly more previous osteomyelitis infections (62.1% vs. 39.1 %, p=0.02) and significantly more reinfections (37.9% vs. 20.9%, p=0.04). width="0"> > > colspan="2" width="258"> > width="162"> MRSA   N=29 > width="168"> No MRSA  N=211 > width="102"> p-value__  > > > colspan="2" width="258"> Male__  > width="162"> 26 > width="168"> 165 > width="102"> 0.15 > > > colspan="2" width="258"> Age__  > width="162"> 50.9±10.8 > width="168"> 50.7±9.5 > width="102"> 0.90 > > > colspan="2" width="258"> BMI (kg/m2) > width="162"> 31.0±8.4 > width="168"> 32.2±7.9 > width="102"> 0.45 > > > colspan="2" width="258"> Diabetes > width="162"> > width="168"> > width="102"> > > > width="24"> > width="234"> Type 2 > width="162"> 27 > width="168"> 195 > width="102"> 0.89 > > > colspan="2" width="258"> Previous Foot Ulcer__  > width="162"> 21 > width="168"> 135 > width="102"> 0.37 > > > colspan="2" width="258"> Previous Amputation__  > width="162"> 15 > width="168"> 87 > width="102"> 0.28 > > > colspan="2" width="258"> Previous Osteomyelitis > width="162"> 18 (62.1%) > width="168"> 83 (39.1%) > width="102"> 0.02 > > > colspan="2" width="258"> Retinopathy > width="162"> 4 > width="168"> 38 > width="102"> 0.57 > > > colspan="2" width="258"> Chronic kidney disease > width="162"> > width="168"> > width="102"> > > > width="24"> > width="234"> Stage 1-2 > width="162"> 3 > width="168"> 26 > width="102"> 0.76 > > > width="24"> > width="234"> Stage 3-4 > width="162"> 3 > width="168"> 33 > width="102"> 0.45 > > > width="24"> > width="234"> ESRD on dialysis > width="162"> 2 > width="168"> 12 > width="102"> 0.79 > > > colspan="2" width="258"> ABI DP > width="162"> 1.2±0.2 > width="168"> 1.1±0.2 > width="102"> 0.09 > > > colspan="2" width="258"> ABI PT > width="162"> 1.2±0.2 > width="168"> 1.2±0.2 > width="102"> 0.55 > > > colspan="2" width="258"> Neuropathy > width="162"> 27 > width="168"> 180 > width="102"> 0.25 > > > colspan="2" width="258"> Laboratory values__  > width="162"> > width="168"> > width="102"> > > > width="24"> > width="234"> Glycated Hemoglobin > width="162"> 9.5±2.9 > width="168"> 9.9±3.3 > width="102"> 0.62 > > > width="24"> > width="234"> White Blood Cell Count   > width="162"> 9.09±3.3 > width="168"> 10.9±4.1 > width="102"> 0.03 > > > width="24"> > width="234"> Erythrocyte Sedimentation Rate   > width="162"> 68.9±35.9 > width="168"> 77.1±45.0 > width="102"> 0.36 > > > width="24"> > width="234"> C-Reactive Protein   > width="162"> 7.5±7.9 > width="168"> 11.4±11.0 > width="102"> 0.07 > > > width="24"> > width="234"> Albumin > width="162"> 3.6±1.08 > width="168"> 3.3±0.5 > width="102"> 0.004 > > > colspan="2" width="258"> Outcomes in Study Period > width="162"> > width="168"> > width="102"> > > > colspan="2" width="258"> Healed > width="162"> 16 > width="168"> 120 > width="102"> 0.86 > > > colspan="2" width="258"> Days to heal > width="162"> 25.8±52.9 > width="168"> 52.5±29.7 > width="102"> 0.61 > > > colspan="2" width="258"> Reinfection > width="162"> 11 (37.9%) > width="168"> 44 (20.9%) > width="102"> 0.04 > > > colspan="2" width="258"> Recurrent osteomyelitis > width="162"> 1 > width="168"> 28 > width="102"> 0.13 > > > colspan="2" width="258"> Reulceration study wound > width="162"> 1 > width="168"> 11 > width="102"> 0.68 > > > colspan="2" width="258"> New ulcer study foot > width="162"> 1 > width="168"> 9 > width="102"> 0.84 > > > colspan="2" width="258"> New ulcer other foot > width="162"> 6 > width="168"> 43 > width="102"> 0.97 > > > colspan="2" width="258"> Readmission foot related > width="162"> 11 > width="168"> 54 > width="102"> 0.16 > > > colspan="2" width="258"> Additional surgery > width="162"> 10 > width="168"> 49 > width="102"> 0.19 > > > colspan="2" width="258"> Amputation, foot > width="162"> 3 > width="168"> 17 > width="102"> 0.68 > > > colspan="2" width="258"> Below knee amputation > width="162"> 1 > width="168"> 7 > width="102"> 0.97 > > > > Conclusion MRSA did not affect healing. Patients with MRSA had significantly higher rate of reinfection but no differences in any other outcomes.