Community-acquired Staphylococcus aureus is a major pathogen responsible for skin and soft tissue infections (SSTIs). This study aimed to investigate the prevalence and molecular characteristics of community-acquired S. aureus isolates recovered from paediatric patients with SSTIs in Shanghai, China. Between January 2015 and January 2018, 91 community-acquired S. aureus isolates were characterised by antibiotic susceptibility, multilocus sequence typing (ST), staphylococcal protein A gene (spa) type and virulence genes. Methicillin-resistant S. aureus (MRSA) strains were also characterised by staphylococcal cassette chromosome mec (SCCmec) type. Forty-one (45.1%) S. aureus isolates were MRSA. ST59 (33.0%, 30/91) was the most common sequence type, and t437 (18.7%, 17/91) was the most common spa type. SCCmec IV and V accounted for 61.0% and 34.1% of all MRSA isolates, respectively. Each isolate carried at least six virulence genes. The positive rates of Panton-Valentine leukocidin genes among all S. aureus, MRSA and methicillin-susceptible S. aureus isolates were 30.8% (28/91), 39.0% (16/41) and 24% (12/50), respectively. The prevalence of community-associated MRSA was surprisingly high among children with community-acquired SSTIs in Shanghai. ST59-t437 was the most prevalent community-acquired S. aureus clone causing SSTIs.

Introduction: Skin and soft tissue infections (SSTIs) are a common reason for presentation to an emergency department (ED). Although many patients with mild SSTI are managed with oral antibiotics, those with mild-moderate infections are often treated with parenteral antibiotics, managed in EDs as outpatients using once daily intravenous cefazolin combined with oral probenecid. The purpose of our study was to determine if cephalexin 500 mg orally four times daily was non-inferior to cefazolin 2 g intravenously daily plus probenecid 1 g orally daily in the management of uncomplicated mild-moderate SSTIs patients presenting to the ED.. Methods: This was a prospective, multi-center, double dummy-blind, randomized controlled non-inferiority trial conducted at two tertiary care teaching hospitals in Canada. Patients were enrolled if they presented to the ED with an uncomplicated SSTI, in a 1:1 fashion to oral cephalexin or intravenous cefazolin plus oral probenecid for up to 7 days. The primary outcome was failure of therapy at 72 hours. Clinical cure at 7 days, intravenous to oral step-down, admission to hospital and adverse events were also evaluated. Results: 206 patients were randomized with 104 patients in the cephalexin group and 102 in the cefazolin and probenecid group. The proportion of patients failing therapy at 72 hours was similar between the treatment groups (4.2% and 6.1%, risk difference 1.9%, 95% CI (-3.3% to 7.1%), p-value for non-inferiority=0.001). Clinical cure at seven days was not significantly different (100% and 97.7%, risk difference -2.3%, 95% CI (-4.9% to 0.3%), p-value for non-inferiority=0.008). Conclusion: Cephalexin at appropriate doses appears to be a safe and effective alternative to outpatient parenteral cefazolin and probenecid in the treatment of uncomplicated mild to moderate SSTIs who present to the ED.

Vibrio alginolyticus causes soft tissue and bloodstream infection; little systematically collected clinical and epidemiological information is available. In the USA, V. alginolyticus infections are reported to the Cholera and Other Vibrio Illness Surveillance system. Using data from 1988 to 2012, we categorised infections using specimen source and exposure history, analysed case characteristics, and calculated incidence rates using US Census Bureau data. Most (96%) of the 1331 V. alginolyticus infections were from coastal states. Infections of the skin and ear were most frequent (87%); ear infections occurred more commonly in children, lower extremity infections more commonly in older adults. Most (86%) infections involved water activity. Reported incidence of infections increased 12-fold over the study period, although the extent of diagnostic or surveillance bias is unclear. Prevention efforts should target waterborne transmission in coastal areas and provider education to promote more rapid diagnosis and prevent complications.

We investigated the virulence gene carriage and molecular type characteristics of Staphylococcus aureus isolates from bloodstream infections (BSIs) and skin and soft tissue infections (SSTIs) in children. A total of 71 isolates, 16 of which were methicillin-resistant S. aureus (MRSA), were investigated by PCR for virulence-associated gene profiles, sequence type and spa type. This revealed that 76·7% and 53·7% of the SSTI and BSI isolates, respectively, exhibited simultaneous carriage of ⩾10 virulence genes. Compared to BSI isolates, carriage rates for hla, hlb, cna, clfA, seb, sec and pvl genes were significantly higher in SSTI isolates. By contrast, carriage of eta, etb and sea was significantly higher for BSI isolates. Thirty-four sequence types (STs) and 36 spa types were identified in the 71 isolates and included 14 novel STs and four novel spa types. ST59-MRSA-IV/V-t437 was the most common clone in the MRSA isolates. We concluded that virulence determinants are widely distributed in isolates of S. aureus strains from children with BSIs and SSTIs, with an unexpectedly high rate in SSTI isolates. Future profiling of S. aureus virulence determinants may allow the prediction of severity and outcome for children with these infections.