To determine the bacterial agents responsible for hospital acquired septicemia and to determine the antibiotic sensitivity profile of the bacterial isolates

Abstract

Aim: To determine the bacterial agents responsible for hospital acquired septicemia and to determine the antibiotic sensitivity profile of the bacterial isolates. Material and Methods: This was a prospective observational study conducted in the Department of Microbiology Nalanda Medical College and Hospital,Patna,Bihar, India from Sept 2019 to March 2020.A total of 500 patients with suspected blood stream infection were included for this study. The sample collected was inoculated immediately into culture bottle containing 70 ml to Brain Heart infusion (BHI) broth. The culture bottle was incubated at 35-37^oC aerobically. After 24h incubation, the sample was sub cultured on to Blood agar, MacConkey agar, Chocolate agar and special media which were suitable for isolation and identification of the species. Antimicrobial susceptibility test Antimicrobial sensitivity was determined by Kirby Bauer’s disc diffusion method on Mueller Hinton agar (MHA). Results: A total of 500 blood samples were collected for blood culture in present study among that 90(18%) were culture positive. Out of 90 positive cultures 60(66.67%) were male while 30(33.33%) were female. The positive samples belonged to maximum from infants 46(51.11%) followed by adults 44 (48.89%). Out of 90 positive cultures, 44 (48.89%) were gram-positive, 41 (45.55%) were gram-negative and 5 (5.56%) were Candida spp. Among the 90 isolates, the most predominant organism was Klebsiella species 26(28.88%), followed by Staphylococcus aureus 16(17.78%) and the least was Escherichia Coli 2(2.22%). Among Gram positive sepsis, Staphylococcus aureus was found to be most sensitive to vancomycin (93.75%) & linezolid (93.75%) followed by amoxyclav (68.75%), amoxacillin (68.75%), tetracycline (56.25%), ciprofloxacin (56.25%) &netilmycin (50%). Low sensitivity to clindamycin (37.5%), cotrimoxazole (37.5%), gentamycin (43.75%) & least sensitive to erythromycin (12.5%), ampicillin (12.5%) and penicillin. Klebsiella spp. showed 88.46% sensitivity for imipenem followed by amikacin (61.54%), tetracycline (46.15%), aztreonam (42.30%), gentamycin (38.46%), netilmicin (38.46%) and ciprofloxacin (38.46%). Among the antibiotics used for susceptibility testing for gram positive isolates, vancomycin (95.24%) & linezolid (97.67%) showed highest activity. Conclusion: The most predominant organism was Klebsiella species followed by Staphylococcus aureus. Imipenem was the most effective drug for gram negative isolates while Vancomycin & Linezolid were most effective against gram positive isolates.

Keywords: blood stream infections, bacterial profile, antimicrobial susceptibility.