Analysis of bloodstream infections and antimicrobial resistance patterns in patients attending Lancet Clinical Laboratories, 2023–2024

Abstract

Bloodstream infections (BSI) are a primary global health concern, especially in developing countries including Zimbabwe. In Zimbabwe, the delayed turnaround of blood culture results and lack of data on antibiotic resistance patterns emphasize the need for improved empirical treatment guidelines. This study aimed to identify the bacteria isolates in positive blood cultures and their antimicrobial resistance patterns in patients clinically suspected of bloodstream infections. This study was a retrospective cross-sectional study, analyzing 385 blood culture records from patients clinically suspected of bloodstream infections at Lancet Clinical Laboratory. The BACTEC blood culture system was used for the incubation of blood culture bottles followed by biochemical identification of bacteria plus antimicrobial susceptibility testing on cultures that would have shown positive growth. The patient records of blood culture results were collected from the laboratory's information system (MedTech) covering the period from January 2023 to December 2024. A list of blood culture patient results was created in an Excel sheet using data from MedTech. Using the systematic random sampling method, a sample size of 385 blood culture records was retrieved, systematically organized, and analyzed into tables. Of the 130 culture-positive samples, 86 (66%) were adults and 44 (34%) were pediatric patients. Amongst the culture-positive blood cultures, 69 (53.1%) Gram-positive organisms were isolated and 61 (46.9%) Gram-negative bacteria were isolated. Isolated bacteria were Coagulase-negative Staphylococcus species (CoNS) (46.9%), E. coli (16.9%), Pseudomonas aureginosa (9.2%), Klebsiella pneumoniae (7.7%), S. aureus (6.2%), Enterococcus (6.2%), Acinetobacter baumanni (4.6%) and Panteo (2.3%). Gram-negative isolates showed high resistance to gentamicin (32.0%), cotrimoxazole (43%), and ceftriaxone (28.3%). Also, Gram-negative bacteria E.coli, K.pneumoniae,Pseudomonas aureginosa, Acinetobacter baumanni and Panteo species showed consistent susceptibility with (0.0%) resistance to doripenem, meropenem, and imipenem collectively known as carbapenems. Whilst Coagulase-negative Staphylococcus (CoNS) and S. aureus showed resistance to the commonly used antibiotics cotrimoxazole (39.1%), cloxacillin (34.8%), ceftriaxone (29.0%), tetracycline (29.0%), gentamicin (24.7%), cefoxitin (24.6%), and amoxicillin-clavulanate (20.8%). This study emphasized that CoNS, E.coli, Pseudomonas aureginosa, Klebsiella spp, S.aureus, Enterococcus spp, and Acinetobacter are responsible for bloodstream infections in patients attending Lancet and their antibiotic resistance pattern. A broader sampling across multiple healthcare facilities particularly in public hospitals to ensure a representative population would assist in the guidance of effective BSI empiric antimicrobial treatment in patients.