Correlation Between icaA/B/C/D Gene and Biofilm Formation in Staphylococcus aureus Infection

Abstract

Staphylococcus aureus is a commensal gram-positive bacterium related to various infections in humans. The ability of S. aureus to form biofilm plays an important role in pathogenesis and the presence of the ica gene is known to be related to this biofilm formation. The study was an analytic cross-sectional study aimed at detecting the presence of the ica gene and its correlation with biofilm formation. The samples in this study were patients with S. aureus infection treated at Prof. Dr. dr. I.G.N.G Ngoerah Hospital from October 2020 to January 2021. The total samples were 67 with a dominant age range was 46-65 years (43.3%) and equal gender amount. The three most common diagnoses of S. aureus infection were post-surgical wound infection (wound swab sample) followed by pneumonia (sputum sample) and chronic kidney disease (blood sample). It was revealed that all isolates produced biofilm with different quantities which were grouped into little (62%), moderate (23.8%), and strong (13.4%) and nearly all samples had at least one ica gene notably icaB or icaD. The icaA gene was detected in 29 samples (43.3%), icaB in 60 samples (89.6%), icaC in 37 samples (55.2%), and icaD in 65 samples (97%). The icaA gene significantly correlated with the quantity of the biofilm formed (p=0.002). The more ica genes the isolate possesses, the more the ability to form biofilms quantitatively (p=0.022).