Culture and Sensitivity in Cancer Patients Presenting with Sepsis

Authors: Veena Boswal, Anmol Mahani, Luckshay Sharma, Vipul Nautiyal, Viney Kumar, Mansi Barthwal

Keywords: Cancer, Sepsis, Antibiotic Resistance, Culture and Sensitivity, Bacteraemia, Chemotherapy, Retrospective Study

Abstract: Introduction: Introduction: Cancer management has significantly evolved over recent decades with the advancement of multimodal treatment strategies, including surgery, chemotherapy, immunotherapy, and radiotherapy. While these therapies improve survival and quality of life, they often compromise the patient’s immune system. Chemotherapy and radiotherapy, in particular, target rapidly dividing cells, inadvertently suppressing bone marrow function and reducing the patient’s ability to mount an effective immune response. Immunotherapy, although more targeted, can also cause immune dysregulation, and surgical interventions may predispose patients to postoperative infections. The immunosuppressive state induced by these treatments makes cancer patients especially vulnerable to infections, including life-threatening sepsis. Additionally, in patients with high tumor burden or aggressive malignancies such as high-grade lymphomas or leukemias, tumor lysis syndrome (TLS) can occur. TLS results from the rapid destruction of tumor cells, releasing intracellular contents into the bloodstream, which can lead to electrolyte disturbances, acute kidney injury, and systemic inflammation — all of which may precipitate or exacerbate sepsis. In this vulnerable population, timely recognition of sepsis and appropriate antimicrobial therapy are essential. Identifying the microbiological spectrum and understanding the antimicrobial resistance trends are vital for formulating effective empirical treatment protocols. Aims and Objectives: This study aimed to identify the most common pathogens responsible for sepsis in cancer patients, determine the primary sites of infection, and evaluate the antibiotic resistance patterns of isolated organisms. Additionally, it sought to analyse the correlation between the type of organism (Gram-positive vs. Gram-negative) and clinical outcomes such as ICU admission and mortality, and to assess variations in causative organisms following chemotherapy or radiotherapy. Materials and Methods: This retrospective observational study was conducted between January 2022 and April 2024 at the Departments of Radiation Oncology and Microbiology, Swami Rama Himalayan University. Cancer patients (18–75 years) who presented with sepsis and had positive cultures from blood, urine, chemoports, ET secretions, or pus were included. Demographic data, culture results, antibiotic sensitivity, and treatment history were collected and analysed. Results: Out of 112 cancer patients, the mean age was 61.3 years (range: 14–87), with a male-to-female ratio of 1.67:1. Chemotherapy had been administered to 36.6% of patients and radiotherapy to 16.1%, with sepsis typically occurring within weeks of treatment. Positive cultures were found in 34.8% of cases, most frequently from urine and blood. E. coliwas the most common organism, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa. Gram-negative bacteria predominated and showed resistance to fluoroquinolone and beta-lactams but retained sensitivity to colistin and carbapenems. The average hospital stay was 6.8 days, with longer durations observed in bloodstream infections and multi drug-resistant cases. Conclusion: Gram-negative organisms predominate in cancer-related sepsis. Regular surveillance of pathogen profiles and resistance trends is critical to guiding empirical treatment and improving outcomes.