Molecular Detection of Bone Sialoprotein-Binding Protein (bbp) Genes among Clinical Isolates of Methicillin Resistant Staphylococcus aureus from Hospitalized Orthopedic Wound Patients

Background and Objectives: Methicillin Resistant Staphylococcus aureus (MRSA) is one of the bacteria that are frequently encountered in orthopedic practice causing human skeletal infections due to expression of Genes encoding Microbial Surface Components Recognizing Adhesive Matrix Molecules that aid in microbial invasion of bone. As such, this study was aimed at screening for Bone sialoprotein-binding protein (bbp) Genes among Clinical Isolates of Methicillin Resistant Staphylococcus aureus from Hospitalized Orthopedic Wound Patients.

Methodology: Aseptically, four hundred (400) fracture and post-surgical wound swab samples were collected from orthopedic wound patients and subjected to standard microbiological protocol for isolation and identification of MRSA using Brilliance MRSA II Agar and Double Disc Diffusion Test with inclusion Oxacillin (5μg) and Cefoxitin (30μg). Randomly selected MRSA strains were further screen for Penicillin binding protein 2a (mecA) and Bone sialoprotein-binding protein (bbp) gene by PCR using specific primer.

Results: MRSA had an overall detection rate of 164 (41.0%), with an increase prevalence rate of 86 (21.5%) in post-surgical wound samples, followed by fracture wound samples (78 (19.5%). However, the isolation rate of MRSA was significantly associated with the sample source p value <0.05. Of the ten (10) selected MRSA strain, mecA gene was genetically detected 100 % comprising of 50.0% from postsurgical wound patient (MR1-5) and 50.0% from fracture wound patient (MR6-10) while the bone sialoprotein-binding protein (bbp) gene was identified in 100% of MRSA strain from both post-surgical wound (MR1-5) and fracture wound (MR6-10) patients each accounted for 50.0% of the total amplified gene.

Conclusion: This study report MecA and bbp expression in hospitalized orthopedic wound patients, emphasizing that mecA and bbp detection can be used as a marker of MRSA bone invasion, especially in orthopedic wound infections. To reduce the risk of infection and to halt the clonal proliferation of these virulent strains, a proper wound care/hygiene, comprehensive and ongoing surveillance system that provides epidemiological and genetic information is required.