Prevalence and Distribution of Bacterial Isolates from Blood Cultures Among Patients with Fever: A Retrospective Study

Abstract

Bloodstream infections (BSIs) remain a critical cause of morbidity and mortality worldwide, particularly among febrile patients. Understanding the local epidemiology of bacterial isolates from blood cultures is essential for guiding empiric antimicrobial therapy and improving clinical outcomes. This study aimed to determine the prevalence, distribution, and antimicrobial susceptibility profiles of bacterial isolates recovered from blood cultures of patients presenting with fever. This retrospective cross-sectional study involved analyzing 186 blood culture records of patients presenting with fever. All blood samples were analyzed using routine microbiological procedures which involved culture of samples on suitable media, biochemical identification and antibiotic susceptibility testing (disk diffusion technique). Demographic data (age and sex) the culture result, organism identified and antibiotic susceptibility profile were retrieved and analyzed.

Of the 186 blood cultures analyzed, 33 (17.7%) yielded bacterial growth while 153 (82.3%) showed no growth. Gram-positive organisms constituted the majority of isolates at 72.7% (n=24), with Staphylococcus haemolyticus (n=12, 36.3%) and Staphylococcus aureus (n=11, 33.3%) being the predominant species. Gram-negative organisms accounted for 24.2% (n=8) of all positive cultures. Female patients comprised 55.4% of the study population and demonstrated a slightly higher culture positivity rate (18.4%) compared to males (16.8%). Notably, high rates of multidrug resistance were observed, particularly among Staphylococcus isolates, while vancomycin and linezolid retained full activity. The predominance of Gram-positive organisms underscores the importance of local surveillance data in guiding empiric antimicrobial therapy. The high prevalence of multidrug resistance highlights the urgent need for antimicrobial stewardship programs and continuous monitoring of resistance trends to inform treatment protocols.