Bloodstream Infections and Antibiotic Susceptibility Among Patients With Positive Blood Cultures at a Tertiary Care...

Bloodstream infections (BSIs) are a major cause of sepsis and in-hospital mortality. Context-specific data on antimicrobial resistance are essential for guiding empiric therapy.

A retrospective study was performed among 100 patients with clinically significant positive blood cultures admitted to the medical wards of Teaching Hospital Batticaloa, Sri Lanka, from January 1 to June 30, 2022. Demographic, clinical, microbiological, and outcome data were extracted from patient records. Associations between selected variables and clinical outcome were analyzed using the Statistical Package for Social Sciences version 26 (IBM Corp., Armonk, NY).

The mean age was 53.6 years (SD = 16.31), and 82 (82%) had comorbidities, mainly diabetes mellitus. Coliforms caused 54 (54%) BSIs, and Staphylococcus aureus caused 19 (19%), of which 10/19 (52.6%) were methicillin-resistant Staphylococcus aureus. Urosepsis was the commonest focus of coliform bacteremia, while central line infection was the leading focus in S. aureus bacteremia. Among isolates tested, Coliforms remained susceptible to amikacin (34/35; 97.1%) and carbapenems (30/31; 96.8%), with low susceptibility to the third- and fourth-generation cephalosporins. S. aureus isolates showed good susceptibility to trimethoprim-sulfamethoxazole and clindamycin, and all isolates tested against penicillin were resistant. Among the patients with known outcomes, in-hospital mortality was 30/90 (33%). Age under 40 years and admission quick Sequential Organ Failure Assessment (qSOFA) score 0 were independently associated with survival.

Coliform BSIs of urinary origin predominated and showed substantial resistance to commonly used antibiotics. Admission qSOFA score was independently associated with survival to discharge in this cohort and may support bedside risk stratification for adults with suspected sepsis in resource-limited settings, like in Sri Lanka.