Detection of ESBL Producing Escherichia coli isolates from blood cultures and its effect on outcome of Sepsis Patients at a rural based tertiary care and teaching hospital in Vadodara district, Gujarat

Background: Sepsis is one of the most common clinical conditions that cause substantial morbidity and mortality all over the world. Blood culture is considered to be the gold standard for the identification of bacteria as a cause of sepsis along with the pattern of antibiotic susceptibility that helps clinicians to choose the appropriate empirical antibiotic. E. coli, belonging to the family Enterobacteriaceae, is a very important pathogen causing infections in humans. It causes a number of important clinical conditions like urinary tract infections, diarrhea, peritonitis, visceral abscesses, endovascular infections, septicemia pneumonia, meningitis, osteomyelitis, wound and soft tissue infections. Due to increased resistance to drugs and ability to produce variety of beta-lactamase enzymes (extended-beta lactamases) poses a difficulty in treating infections caused due to E. coli. Objectives: Objectives of this study were (a) to detect ESBL production amongst the E.coli isolated from the blood cultures of patients with sepsis and (b) to determine its effect on the outcome of sepsis patients from a rural based tertiary hospital in Vadodara district of Gujarat. Materials and methods: A total of 48 E. coli isolates were obtained from the blood culture of 46 patients with clinically diagnosed sepsis. These 48 E. coli isolates were tested for detection of ESBL production according to the CLSI guidelines using phenotypic screening & confirmatory methods. Results: From a total of 48 E. coli isolates obtained from blood culture of 46 clinically diagnosed sepsis, 24 were female patients (as 2 patients had 2 blood samples cultured) and 22 were males. Of the total 48 E. coli isolates tested for ESBL production, 23 (47.91%) isolates from 23 (50%) patients were found to be producing ESBL and 25 (52.08%) isolates from other 23 (50%) patients did not produce ESBL. Of the 23 patients with ESBL producing E. coli, 14 (60.86%) patients did not survive the episode of sepsis, whereas 7 (30.43%) survived and for 2 (8.69%) patients the outcome was not known as they took discharge against the medical advice. Amongst the 23 patients with 25 blood samples yielding non-ESBL producing E. coli, 8 (34.78%) did not survive, 14 (60.86%) survived and for 1(4.34%) patient the outcome was not known. Thus the mortality was more in patients with sepsis due to ESBL producing E. coli as compared to patients with non-ESBL producing E.coli. Also the urinary tract/kidneys were the common source of infection and kidneys were the organ affected. The ESBL producing E. coli showed a higher resistance to most of the antibiotics used but a higher susceptibility to Imipenem and Ertapenem. Conclusion: The findings of our study suggests a higher prevalence of ESBL producing E. coli, which exhibit a higher resistance to most of the antibiotics, are associated with greater mortality and pose a real challenge in the management of patients with sepsis.