First Report of Fatal Infection Caused by Community-acquired Methicillin-resistant Staphylococcus aureus USA300 Clone in a Collegiate Athlete

Community-Acquired Methicillin-Resistant Staphylococcus aureus Strain Positive for the Panton-Valentine Leucocidin Gene in a Middle-Aged Patient With Multiple Septic Pulmonary Emboli

A 59-year-old man suffered from fever and chest pain for three days following an accidental bite to a lip ulcer. His lower lip showed swelling and tenderness, and chest computed tomography showed multiple bilateral nodules. He was diagnosed with septic pulmonary embolism and a lip abscess, and blood, sputum, and lip abscess cultures confirmed the presence of methicillin-resistant Staphylococcus aureus (MRSA). Despite the initiation of vancomycin, he rapidly developed respiratory failure and septic shock, necessitating intubation and noradrenaline support. Gentamicin was added on the seventh day of admission due to an insufficient effect, and vancomycin was switched to linezolid on the 14th day of admission. However, his respiratory failure persisted as bilateral pneumothorax developed. Blood culture was negative on the 14th day after admission, but the patient died on the 15th day after admission. The MRSA isolate was tested for the presence of the Panton-Valentine leukocidin (PVL) gene in conjunction with the USA300 strain. The prevalence of community-acquired (CA)-MRSA in the USA300 clone is increasing but still low in Japan, and this type of infection is commonly observed in people of all ages; this case is the first instance reported in Japan of a middle-aged patient with septic pulmonary embolism. Given the anticipated global increase in CA-MRSA infection caused by the USA300 clone and the emergence of USA300 with altered pathogenicity, it may be crucial to suspect PVL-positive CA-MRSA infections even in middle-aged or elderly patients presenting with septic pulmonary embolism as community infections.

Methicillin Resistant Staphylococcus aureus and public fomites: a review

Staphylococcus genus is a Gram-positive coccus normally associated with skin and mucous membranes of warm-blooded animals. It is part of the commensal human microflora, or found in animals, or contaminating surfaces in the community and hospital settings. Staphylococcus aureus is the most pathogenic species belonging to this genus, as it possesses a collection of virulence factors that are expressed solely to evade the immune system. The increase in the misuse of antimicrobial agents predisposed S. aureus to develop antibiotic resistance, including the resistance to methicillin which led to the emergence of Methicillin-Resistant S. aureus (MRSA). MRSA is considered one of the most dangerous nosocomial pathogens causing many hard to treat infections in hospitals and was named as Hospital Associated MRSA (HA-MRSA). Over the past 20-25 years, MRSA was isolated from community settings and thus Community Associated MRSA (CA-MRSA) has emerged. Inside hospitals, MRSA has been isolated from fomites in contact with patients, as well as staff's protective and personal items. This review highlights the worldwide prevalence of MRSA on fomites within the contexts of hospital and community settings.