Background: The molecular epidemiology of Staphylococcus aureus strains causing staphylococcal scalded skin syndrome (SSSS) in the United States has not been described. We analyzed patient and S. aureus isolate characteristics associated with SSSS in children at Texas Children’s Hospital. Methods: Patients with SSSS were identified by ICD9/10 codes and available S. aureus isolates were identified from an ongoing S. aureus surveillance study. Medical records were reviewed for 58 patients with available S. aureus isolates. Isolate analyses included PCR for agr group, pvl (lukSF-PV), tst, eta and etb, pulsed-field gel electrophoresis, multi-locus sequence typing and antimicrobial susceptibilities. Results: Cases of SSSS increased from 2.3/10,000 admissions in 2008 to 52.6/10,000 admissions in 2017 (P < 0.0001). The 58 study cases (57 methicillin-susceptible S. aureus, 1 MRSA) with isolates were from 2013 to 2017. The majority (88%) of isolates was of clonal cluster (CC) 121, agr group IV, pvl −, tst − and carried eta and/or etb and 26% were clindamycin resistant. Twelve ST121 isolates had high level resistance to mupirocin. Patients were treated with standard supportive care plus systemic antibiotics [clindamycin alone or in combination with another antibiotic (n = 44)]. One patient had a recurrent SSSS and one patient was transferred to a burn unit on day 3. Conclusions: Cases of SSSS are increasing at our hospital. Most S. aureus strains isolated were of one CC, CC121 and carried eta and etb. Supportive care plus clindamycin was effective treatment. We speculate that CC121 was recently introduced to our region and is responsible for the increasing numbers of SSSS cases observed at Texas Children’s Hospital.

Background Microbial surface component recognizing adhesive matrix molecules (MSCRAMMs) facilitate Staphylococcus aureus adherence to host tissue. We hypothesized that S. aureus isolates from implant-associated infections (IAIs) would differ in MSCRAMM profile and biofilm formation in vitro compared to skin and soft tissue infection (SSTI) isolates. Methods Pediatric patients and their isolates were identified retrospectively. IAI and SSTI isolates were matched (1:4). Pulsed field gel electrophoresis was performed to group isolates as USA300 vs. non-USA300. Whole genome sequencing was performed and raw sequence data were interrogated for presence of MSCRAMMs (clfA, clfB, cna, ebh, efb, fnbpA, fnbpB, isdA, isdB, sdrC, sdrD, sdrE), biofilm-associated (icaA,D,B,C), and Panton-Valentine leukocidin (lukSF-PV) genes, accessory gene regulator group, and multilocus sequence types. In vitro biofilm formation was assessed for 47 IAI and 47 SSTI isolates using a microtiter plate assay. Conditional logistic regression was performed for analysis of matched data (STATA11, College Station, TX). Results Forty-seven IAI and 188 SSTI isolates were studied. IAI isolates were more often methicillin susceptible S. aureus and non-USA300 vs. SSTI isolates [34 (72%) vs. 79 (42%), p = 0.001 and 38 (81%) vs. 57 (30%) p <0.001, respectively]. Greater than 98% of isolates carried clfA, clfB, efb, isdA, isdB, and icaA,D,B,C while cna was more frequently found among IAI vs. SSTI isolates (p = 0.003). Most isolates were strong biofilm producers.

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