FREQUENCY OF STAPHYLOCOCCUS AUREUS IN BLOOD STREAM INFECTIONS AND THEIR DRUG SUSCEPTIBILITY PATTERN

Background: Staphylococcus aureus is important cause of blood stream infections. The objectives of this study were to determine the frequency of Staphylococcus aureus in blood stream infections and their antimicrobial drug susceptibility pattern. Materials & Methods: This cross-sectional study was conducted at the Department of Pathology, Shaikh Zayed Hospital, Lahore from April 2018 to March 2019. The sample size was 1527 positive blood cultures for bacteria selected through consecutive sampling technique. Research variables were; presence of positive blood cultures, presence of staphylococci in positive blood cultures, types of staphylococci and types of staphylococcus aereus. Frequency and percentage of blood stream infection caused by Staphylococcus aureus and susceptibility of Staphylococcus aureus to various antimicrobial drugs was detected by disc diffusion and e-strip method. Results: Out of 12744 blood cultures, 1527(11.98%) were positive for bacteria. Out of these 1527, 339(22.20%) were positive for staphylococci. Out of these 339, 87 (5.69%) were staphylococcus aureus. Out of these 87, 48 (3.14%) were methicillin resistant (MRSA). Susceptibility of S. aureus isolates to various commonly used drugs was also detected. Conclusion: Staphylococcus aureus is a significant cause of blood stream infection and can exhibit multi-drug resistance. Therefore drug susceptibility profile of pathogens prevalent in hospital should be monitored and kept in mind when prescribing antimicrobial drugs before getting results of antimicrobial drug susceptibility tests.