Exfoliative toxin serotype genes and antibiotic resistance of staphylococcus aureus isolated from children with staphylococcal scalded skin syndrome / 中华皮肤科杂志

ABSTRACT

Objective To investigate the exfoliative toxin serotype genes and antibiotic resistance of Staphylococcus aureus (SA) isolated from children with staphylococcal scalded skin syndrome (SSSS). Methods In total, 108 strains of SA were isolated from 36 patients with SSSS, 36 patients with impetigo and 36 patients with abscess. Multiplex PCR was used to detect the staphylococcal exfoliative toxin A, B and D genes, Kirby-Baner method to test the susceptibilities of SA strains to 20 antibiotics. Results All the 36 SA isolates from SSSS patients were ET-positive, and 2 (6%) produced ETA, 7 (19%) ETB, 27 (75%) both ETA and ETB; of the 36 isolates from patients with impetigo, 78% produced ET, and 14% produced ETA, 64% produced both ETA and ETB, while no single ETB-producing strain was found; ET was detected in only one (2.8%) SA isolate from abscess patients, which produced both ETA and ETB. ETD was detected in none of the SA isolates. There was a statistical difference in the distribution of ET serotype among the three diseases (χ2=89.4, P < 0.01) and the proportion of ET-producing strains in SSSS group was signifi-cantly higher than that in impetigo group (χ2=9.0, P < 0.01) and abscess group (χ2= 68.1, P < 0.01). All the SA isolates were highly resistant to penicilin, ampicillin, macrolides and clindamycin, but sensitive to other 15 common antibiotics such as cephalosporin. Two strains of MRSA were found in patients with abscess. Conclusion In Chongqing, ET-producing SA is the common pathogenic bacteria of SSSS and impetigo, and most of SA strains produce both ETA and ETB.