Prevalence and genotypic characteristics of Panton-Valentine Leukocidin-producing Staphylococcus aureus isolates obtained in Jos, North Central Nigeria

Abstract

Background: Staphylococcus aureus is an opportunistic pathogen that colonizes and causes infections in humans. Panton Valentine Leukocidin (PVL) is a cytolytic toxin produced by some strains of S. aureus and are mostly associated with skin and soft tissue infections and necrotizing pneumonia. Aim: To investigate the prevalence and genotypic characteristics of PVL-positive S. aureus strains cultured from patients in three tertiary hospitals in Jos, Nigeria. Methods: Two hundred and fourteen clinical S. aureus isolates were obtained from three tertiary hospitals in Jos. Polymerase chain reaction was used to detect lukSF-PV gene that encodes PVL, and sensitivity to antimicrobial agents was performed on PVL-positive S. aureus. Genotypic characteristics of the PVL-positive S. aureus was determined by spa typing and multilocus sequence typing (MLST). Results: The genes for PVL were detected in 67/214 (31.3%) of S. aureus isolates. Majority of the PVL-positive isolates were obtained from wound (n=37; 55.2%), blood (n=11; 16.4%) and urine (n=10; 14.9). Most of PVL-positive isolates (n=58; 34.7%) were methicillin sensitive S. aureus (MSSA) while nine isolates (19.1%) were methicillin resistant S. aureus (MRSA). Spa typing identified 14 different spa types, dominated by t355 (n=33; 49.3%), followed by t174 (n=7; 10.4%), t019 and t159 (n=5; 7.5%). MLST revealed six sequence types (ST) namely, ST152 (n=35), ST121 (n=9), ST1 (n=8), ST30 (n=8), ST772 (n=6) and ST15 (N=1). Conclusion: This study revealed that 31.3% of S. aureus isolated in Jos hospitals carried genes for PVL, belonged to six sequence types and 14 spa types with t355-ST152-MSSA as the dominant genotype.