Methicillin-Resistant Staphylococcus aureus in Diabetic and Non-diabetic Foot Infections

Authors

Lawrence A Lavery
Mario C Reyes
Mehmet Suludere
Bijan Najafi
Matthew Sideman
Michael C Siah
Arthur N Tarricone

Publication Date

9-1-2024

Journal

International Wound Journal

DOI

10.1111/iwj.70039

PMID

39268931

PMCID

PMC11393987

PubMedCentral® Posted Date

9-13-2024

PubMedCentral® Full Text Version

Post-print

Published Open-Access

yes

Keywords

Humans, Methicillin-Resistant Staphylococcus aureus, Male, Female, Diabetic Foot, Retrospective Studies, Middle Aged, Staphylococcal Infections, Aged, Incidence, Adult, Osteomyelitis, Aged, 80 and over, Reinfection, Soft Tissue Infections, amputation, diabetes, infection, osteomyelitis, ulcer

Abstract

To identify the incidence of methicillin-resistant Staphylococcus aureus (MRSA) infection, reinfection and clinical outcomes. Four hundred forty-six patients that were admitted to the hospital with moderate or severe foot infections were retrospectively reviewed. Tissue and bone cultures were obtained from the index hospital admission. Conversion was defined as methicillin susceptible Staphylococcus aureus in the first culture and subsequently MRSA when there was a reinfection. The incidence of MRSA was 7.8% (n = 35), with no significant difference between soft tissue infections (7.7%) and osteomyelitis (8.0%). MRSA incidence was 9.4 times higher in non-diabetics (23.8% vs. 3.2%, p = < 0.01). The incidence of reinfection was 40.8% (n = 182). Conversion to MRSA was seen in 2.2% (n = 4) total, occurring in 5.4%. Non-diabetics were 20.1 times more likely to have MRSA reinfection than people with diabetes (28.6% vs. 1.9%, p <  0.001). MRSA patients had a higher proportion of healed wounds (82.4% vs. 69.3%, p = 0.02). There were no differences in other clinical outcomes in MRSA vs. other infections in reinfection (28.6% vs. 24.3%, p = 0.11), amputation (48.6% vs. 52.0%, p = 0.69) or hospitalization (28.6% vs. 42.6, p = 0.11). The incidence of MRSA for the first infection (7.8%), reinfection (6.0%) and conversion to MRSA (2.2%) was low. MRSA was 9.4 times more common in people without diabetes.