Epidemiology and Antibiotic Resistance of Bacterial Bloodstream Infections in Hematological Malignancies: A ۷-Year Study from Northeastern Iran

Background: Bacterial bloodstream infections (BSIs) caused by multidrug-resistant pathogens remain a major concern in cancer patients, particularly those with hematological malignancies. Their increased susceptibility underscores the importance of timely, targeted empirical therapy. This study aimed to describe the epidemiology and antimicrobial resistance of bacterial pathogens in Northeastern Iran.Methods: A retrospective review was conducted of BSI episodes between ۲۰۱۱ and ۲۰۱۸ in patients with hematological cancers admitted to a tertiary care center in Mashhad, Iran. Clinical and microbiological data were analyzed to determine pathogen distribution and resistance patterns.Results: Among ۱۰۷ patients with confirmed bacteremia, ۶۰ (۵۶.۱%) were male, with a mean age of ۴۳.۸ ± ۱.۸ years. Acute myeloid leukemia was the most frequent malignancy (۴۱.۱%), followed by acute lymphoblastic leukemia (۲۴.۳%). The mean hospitalization duration was ۲۰ ± ۱.۳ days, and ۶۴% of patients survived to discharge. The predominant isolates were Staphylococcus aureus (۱۵.۹%), Acinetobacter spp. (۱۵.۰%), Enterococcus spp. (۱۳.۱%), and Staphylococcus epidermidis (۱۲.۱%). Neutropenia occurred in ۶۲ patients (۴۲.۱%) and was significantly associated with infections due to S. aureus and Escherichia coli (P < ۰.۰۰۱). Antibiotic susceptibility testing revealed vancomycin was most effective, with susceptibility rates of ۹۲.۳% for S. epidermidis and ۸۲.۴% for S. aureus. Enterococcus spp. showed ۷۸.۶% sensitivity to linezolid, while only ۵۲.۹% of S. aureus isolates were susceptible to ciprofloxacin.Conclusion: The observed resistance patterns differ from global trends, underscoring the importance of region-specific empirical therapy. Ongoing surveillance and tailored treatment strategies are essential to improve outcomes in patients with hematological malignancies.

کلیدواژه ها:

Antibiotics ، Multidrug resistance ، Hematological malignancy ، Resistance patterns