Multiyear experience with blood culture results from a tertiary care hospital in Saudi Arabia: a retrospective study | BMC Infectious Diseases

This study evaluates blood culture results, contamination rates, and resistance patterns based on data from a laboratory of a tertiary hospital in Jazan, Southwestern Saudi Arabia. Blood culture is crucial in diagnosing BSI, guiding appropriate antibiotic therapy, and improving patient outcomes. However, the reliability of this diagnostic tool is hindered by contamination rates, consequently causing unnecessary antibiotic use, resource wastage, and increased healthcare costs [1]. This study revealed a contamination rate of 6.3% in 2018, followed by a notable decline in the recent years of 2022 and 2023 with a rate of 3.74% and 4.25%, respectively (Fig. 1; Table 1). This reduction resulted in rates close to the CLSI recommendation of < 3% [1, 10] and can be attributed to initiatives that were implemented after 2018 such as improved infection control measures, stricter adherence to aseptic blood culture collection techniques, increased staff training and awareness programs, the implementation of dedicated phlebotomy teams, and strengthen antimicrobial stewardship policies. Lessons learned from the COVID-19 pandemic may have contributed to improved hand hygiene compliance, stricter aseptic techniques in sample collection, and increased vigilance in antimicrobial stewardship efforts [11]. These rates that were reported in 2018, 2022, and 2023 are comparable to what has been reported in other regional and international studies [1, 12,13,14,15,16,17,18,19,20]. Regional studies from Saudi Arabia found higher contamination rates as reported by Hemeg et al. who conducted a prospective study in 2017 in Almadina, Western Saudi Arabia, and reported a 6.6% rate of positive blood culture contamination [1]. Similarly, Al-Hamad et al. observed a contamination rate of 8% in the Eastern region of the country in 2016, which significantly decreased, 6 months later, from 8% to 5% after implementing an educational intervention program targeting nurses [19]. In other international settings, Ramos (2013) in Texas and Bowen et al. (2016) at Stanford reported a contamination rate of 6% and 4%, respectively [13, 14]. The consistent challenges seen across these studies reinforce the need for continuous quality improvement initiatives. Other key findings in our study include reduced ESBL prevalence (10.29% to 3.25%) and decreased Klebsiella spp. and Pseudomonas spp. rates. Despite progress, the slight increase in 2023 indicates the need for continued vigilance and standardized collection protocols.

Our study’s analysis of factors associated with a high rate of contaminated blood cultures revealed significant associations with patient age group and department [Table 1]. Similar findings have been reported by Hemeg et al., who observed a higher likelihood of contamination in samples from elderly patients [1]. Additionally, overcrowded emergency departments have been identified as a hotspot for contamination, attributed to difficulties in establishing intravenous lines in patients of extreme age by inexperienced nursing staff, lack of dedicated phlebotomy teams, and improper aseptic techniques during blood sampling [13,14,15,16,17,18,19,20,21,22,23,24,25].

Unlike 2018, no seasonal variation was observed in 2022 and 2023. Hemeg et al. identified two seasonal peaks in contaminated blood culture [1]. These peaks were linked to periods when senior nurses were on leave during the Hajj season and school vacations, which led to higher contamination rates due to crowded conditions. In contrast, the absence of seasonality in 2022 and 2023 that we observed likely reflects enhanced infection prevention and control measures, standardized blood culture collection protocols, and improved staffing policies. These improvements align with Saudi Arabia’s national CLABSI reduction initiative, launched in 2022, which led to a 48.8% decline in CLABSI rates. Key interventions, including clinician training, real-time infection surveillance, and stricter aseptic techniques, have contributed to improved blood sampling practices and reduced contamination rates [12].

Studying positive blood cultures that reflect true BSI in highly critical settings such as the ICU is crucial in healthcare. It serves as a key diagnostic tool for detecting and identifying BSI, guiding effective antibiotic treatment, and enhancing patient outcomes. We compared BSI in ICU patients vs. other patients for the data collected in 2022 and 2023 as they are more recent, robust, and reflect current infection control practices, antimicrobial resistance patterns, and clinical management strategies [Table 3]. Our findings confirm that Gram-negative bacteria predominated in ICU patients, particularly Klebsiella spp. aligning with previous reports that found higher Gram-negative infection rates in ICUs compared to general wards [26,27,28]. Further, Gram-negative resistance patterns, including ESBL and CRE, were more common in ICU patients, highlighting the urgency of strengthing antimicrobial stewardship in critical care settings.

Conversely, MRSA was more common in non-ICU patients, suggesting a potential reservoir of resistant bacteria in the community. This aligns with existing reports attributing community-acquired MDROs to person-to-person transmission and misuse of antibiotics [26,27,28,29]. The emergence of community-acquired CRE is an alarming trend in the Middle East and globally, emphasizing the need for expanded surveillance and targeted infection control strategies [28, 29].

This study indicates the urgent importance of implementing robust hospital-wide antimicrobial stewardship programs to address the challenges posed by MDRO in both ICU and non-ICU settings. The decline of ESBL from 10.29 to 3.25% suggests that current interventions are effective, but sustained efforts are necessary and further studies are required to assess the impact of MDROs at the patient care and public health levels [29,30,31]. Antimicrobial stewardship programs are essential for ensuring the responsible use of antimicrobials, safeguarding patient safety, and maintaining the effectiveness of antibiotics. These programs employ a multidisciplinary approach to encourage judicious prescribing practices, reduce unnecessary antimicrobial use, and combat the rise of resistant microorganisms. Complementing these efforts, infection control programs focus on preventing and managing the spread of infections within healthcare facilities [30,31,32].

Although this study provides valuable insights, certain limitations should be acknowledged. Firstly, it is a retrospective study focusing on the data from 2018, 2022, and 2023, which limits real-time variability assessment. However, completing this study with recent data strengthens the reliability of the trends observed. It is important to note that after 2018, there were comprehensive renovations and improvements in the hospital’s infrastructure, aligned with the goals of Saudi Vision 2030 in enhancing the healthcare system. These improvements encompassed various projects to reinforce the application of infection control policies, launch an antimicrobial stewardship program, and implement bundles to reduce HAI. However, our study faces limitations in explaining some unusual results, such as the high number of blood culture requests in 2018 compared to 2022 and 2023, and the underlying reasons for the elevated contamination rate. Moreover, we could not confirm the presence of resistant organisms using molecular techniques as such resources were not available at the time of the study in 2018, but data from 2022 to 2023 followed the national protocol of confirming resistance isolates by molecular testing. In addition, including clinical data comprising morbidity and mortality information would significantly enhance the depth and scope of this project. Despite these limitations, we hope that our study contributes valuable insights to the field and lays the foundation for further research and advancements in healthcare practices in the region.