Based on the susceptibility pattern,
S. aureus found in this patient is clearly a CA-MRSA strain (oxacillin stands in for methicillin susceptibility in many microbiology laboratories). In contrast to health care-associated MRSA strains that retain susceptibility to only vancomycin, daptomycin, linezolid, tigecycline, and quinupristin/dalfopristin, the newer CA-MRSA strains are often susceptible to clindamycin, TMP/SMX, and tetracycline. A risk factor for acquiring CA-MRSA includes close personal contact with infected individuals; an increased incidence of CA-MRSA infection has been shown in athletes who share common objects (eg, athletic equipment, towels, benches, personal items) contaminated with MRSA.3-7 Military recruits, prisoners, Pacific Islanders, Alaskan Natives, Native Americans, and men who have sex with men are also at increased risk for CA-MRSA. Although it is possible to acquire MRSA in a nursing home, this patients age, health status, clinical presentation, and susceptibility pattern suggest that health care-associated MRSA is unlikely. Reptile exposure is a risk for gram-negative infections (particularly Salmonella infections). MRSA skin infections are not acquired by ingestion. CA-MRSA has not been shown to be transmitted by arthropods.
- Close physical contact with other athletes at a health club.
3. Centers for Disease Control and Prevention. Methicillin-resistant Staphylococcus aureus infections among competitive sports participantsColorado, Indiana, Pennsylvania, and Los Angeles County, 2000-2003. MMWR Morb Mortal Wkly Rep 2003;52:793-5.
4. Begier EM, Frenette K, Barrett NL, et al. A high-morbidity outbreak of methicillin-resistant Staphylococcus aureus among players on a college football team, facilitated by cosmetic body shaving and turf burns. Clin Infect Dis 2004;39:1446-53.
5. Kazakova SV, Hageman JC, Matava M, et al. A clone of methicillin-resistant Staphylococcus aureus among professional football players. N Engl J Med 2005;352:468-75.
6. Nguyen DM, Mascola L, Brancoft E. Recurring methicillin-resistant Staphylococcus aureus infections in a football team. Emerg Infect Dis 2005;11:526-32.
7. Lindenmayer JM, Schoenfeld S, OGrady R, Carney JK. Methicillin-resistant Staphylococcus aureus in a high school wrestling team and the surrounding community. Arch Intern Med 1998;158:895-9.
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