Emergence of two populations of methicillin-resistant Staphylococcus aureus with distinct epidemiological, clinical and biological features, isolated from patients with community-acquired skin infections.
BACKGROUND
Community-acquired skin and soft-tissue infections due to methicillin-resistant Staphylococcus aureus (MRSA) are an emerging clinical and epidemiological problem.


OBJECTIVE
To characterize community-acquired skin infections caused by S. aureus, and especially MRSA.


METHODS
From November 1999 to December 2003, we conducted in a French hospital a prospective epidemiological, clinical and bacteriological study of skin infections acquired in the community, applying strict criteria for true community-acquired MRSA (CA-MRSA) and health-care-associated MRSA (HCA-MRSA).


RESULTS
One hundred and ninety-seven patients had 207 skin infections (154 primary and 53 secondary infections). Twenty-two (11%) patients had skin infections caused by MRSA. The incidence of MRSA skin infections acquired in the community rose from 4% in 2000 to 17% in 2003, but the increase was not statistically significant. Six patients (3%) were infected by CA-MRSA and 15 (8%) by HCA-MRSA; one patient was lost to follow-up and could not be classified. CA-MRSA and HCA-MRSA had different epidemiological, clinical and biological characteristics. CA-MRSA infections were more severe than HCA-MRSA infections: all the CA-MRSA infections (six of six, 100%) required surgical treatment, compared with only two (15%) of 13 with HCA-MRSA infection (P < 0.001). CA-MRSA all belonged to the same clonal strain, harbouring an agr type 3 allele and the Panton-Valentine leucocidin genes (not detected in HCA-MRSA) and possessing a specific antibiotype.


CONCLUSIONS
Two populations of MRSA causing skin infections are emerging in the French community, with distinct epidemiological, clinical and biological characteristics.
Del Giudice
P
P
Unité d'Infectiologie-Dermatalogie, Hôpital Bonnet, Fréjus, France. del-guidice-p@chi-frejus-saint-raphael.fr
Blanc
V
V
Durupt
F
F
Bes
M
M
Martinez
J-P
JP
Counillon
E
E
Lina
G
G
Vandenesch
F
F
Etienne
J
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015373:Bacterial Typing Techniques / Q000379:methods; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000382:microbiology; D003428:Cross Infection / Q000188:drug therapy / Q000382:microbiology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D016106:Methicillin Resistance / Q000235:genetics; D008875:Middle Aged; D011446:Prospective Studies; D013207:Staphylococcal Skin Infections / Q000188:drug therapy / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000145:classification / Q000187:drug effects* / Q000235:genetics