Bacteriological Profile and Antimicrobial Susceptibility Pattern of Blood Culture Isolates in Immunocompromised Patients: A Hospital-based Cross-sectional Study

Abstract

Introduction: Immunocompromised individuals have weaker immune systems and they are more likely to develop Bloodstream Infections and have lower ability to fight against infections. Multidrug-resistant bacterial infections require rapid pathogen identification because it enables healthcare providers to start targeted antimicrobial treatment, which leads to better patient outcomes. Aim: To determine the bacterial profile and antimicrobial susceptibility pattern of isolates from blood culture of immunocompromised patients admitted to a tertiary care hospital. Materials and Methods: This hospital-based cross-sectional study was carried out in the Department of Microbiology, National Institute of Medical Sciences and Research, Jaipur, Rajasthan, India, between October 2023 and April 2024. A total of 246 blood samples were collected from immunocompromised individuals under aseptic conditions and processed in the BD BACTEC FX40 automated blood culture system. The standard microbiological and biochemical techniques were used to identify the positive blood cultures. The modified Kirby-Bauer disk diffusion method was used to test for antimicrobial susceptibility, and the Clinical and Laboratory Standards Institute (CLSI) criteria for 2023 were followed in interpreting the results. Results: A total of 246 blood samples were processed, and 75 (30.49%) were culture-positive. Of the patients with culturepositive results, 30 (40%) were female, and 45 (60%) were male. Most of the patients were below 60 years of age. There were 57 (76%) Gram-negative and 18 (24%) Gram-positive bacteria. Gram-negative bacteria commonly present were Escherichia coli 10 (17.54%), Klebsiella pneumoniae 15 (26.31%), and Pseudomonas aeruginosa 18 (31.57%). Staphylococcus aureus, constituting 7 (38.89%) of Gram-positive bacteria, all Methicillin-Resistant Staphylococcus aureus (MRSA). Multidrug resistance was commonly present in Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. Conclusion: The current research demonstrated that people with weakened immune systems face higher risks of developing BSIs, which are caused by multidrug-resistant Gram-negative bacteria. The establishment of enhanced local BSI surveillance systems, together with prompt microbiological testing, will lead to improved antimicrobial treatment decisions, which will result in better treatment results for patients in high-risk categories.