Investigation of fnBP and clf genes prevalence among Methicillin-resistant Staphylococcus aureus strains and assessment of the effects of host factors and clinical specimens on their distribution

Staphylococcus aureus is a common cause of nosocomial infections that has several specific adhesion molecules factors which can be bound to a variety of host matrix extracellular proteins and replaced by host tissues. This binding is mediated by a family of proteins known as microbial surface components known as adhesive matrix molecules (MSCRAMMs) which includes fibronectin-binding protein (FnBP) and fibrinogen binding protein (Clf). Comprehensive studies regarding the genetic abilities of S. aureus isolates especially MRSA which have binding mediators seem essential.
In this study 74572 clinical samples of blood, urine, sputum and other clinical samples of patients who were admitted to Tehran Milad Hospital were collected. 180 Staphylococcus aureus strains were identified after diagnostic tests. In order to determine MRSA isolates Cefoxitin disc diffusion method was used. The presence and frequency of fnbA, fnbB and clf genes was determined by PCR.
From 180 Staphylococcus aureus strains 159 strains (88%) had fnbA gene,47 strains (26%) had fnbB gene and 36 strains (20%) had clf gene. The simultaneous frequency of fnbA and fnbB was 42 (23%), fnbA and Clf was 32 (18%) and fnbB and Clf was 9 (5%). The presence of all three genes together was 9 (5%).
The results showed that there was no significant relationship between fnbA, fnbB and clf genes and clinical sample type, gender and age of patients and MRSA and MSSA isolates.