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Updated: May 3, 2026

Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus MRSA
Published on: February 9, 2011
Staphylococcus aureus toxic shock syndrome toxin-1 endocarditis with muscular metastatic abscesses
Marco Tinelli1, Monica Monaco, Elena Maffezzini
1Division of Infectious and Tropical Diseases, Hospital of Lodi, Italy.
Abstract:
A 42-year-old woman, living in a nursing home for the mentally disabled, with congenital ventricular septal defect and multiple comorbidities, developed endocarditis with vegetations of the interventricular septum and the right coronary aortic leaflet. The main feature of this case was the metastatic embolism leading to multiple and muscular abscesses. Methicillin-sensitive S. aureus, spa type 253 and ST30, producing toxin shock syndrome toxin-1 was isolated from blood cultures. The patient was initially treated with beta-lactam antibiotics without showing clinical response and subsequently with daptomycin and linezolid that improved the patient's clinical symptoms. The effectiveness of treatment with daptomycin and linezolid was partly due to the ability of linezolid to reduce TSST-1 secretion. The portal of entry of the infection was not recognized. TSST-1 production by the strain might have favoured the formation of large cardiac vegetations and the subsequent metastatic dissemination to the muscles.
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