---
title: "Bloodstream infection pathogens and antimicrobial resistance at Amhara Public Health Institute, Et"
id: "plos-one-7-bacterial-profile-and-antimicrobial-resistance-patterns-of-bloodstream"
canonical_url: "https://medichelpline.com/clinical-feed/plos-one-7-bacterial-profile-and-antimicrobial-resistance-patterns-of-bloodstream"
content_type: "clinical_feed_article"
specialty: "Infectious Disease"
source_name: "PLOS ONE (Medicine)"
source_url: "https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0354710"
published_at: "2026-07-27T14:00:00.000Z"
evidence_level: "Journal Feed"
license: "CC-BY-NC-4.0 / Informational Use"
---
# Bloodstream infection pathogens and antimicrobial resistance at Amhara Public Health Institute, Et
## Provenance & Clinical Metadata
- **Canonical URL:** https://medichelpline.com/clinical-feed/plos-one-7-bacterial-profile-and-antimicrobial-resistance-patterns-of-bloodstream
- **Specialty:** [Infectious Disease](https://medichelpline.com/clinical-feed/infectious-disease.md)
- **Primary Source:** PLOS ONE (Medicine)
- **Source URL:** [Original Journal Publication](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0354710)
- **Published At:** 2026-07-27T14:00:00.000Z
- **Evidence Rating:** Journal Feed
## Executive GIST (TL;DR)
- Retrospective analysis of 676 blood culture records from Amhara Public Health Institute (APHI), January 1, 2020–December 30, 2023, to define bacterial causes of suspected bloodstream infections (BSIs) and antimicrobial resistance patterns. - True bacterial pathogens were recovered in 50.3% (340/676) of cultures; **Gram-negative** organisms predominated (61.2%, 208/340) versus Gram-positive (38.8%, 132/340). - ESKAPEE pathogens comprised 96.5% (328/340) of isolates; leading species were Klebsiella spp. (25.9%, 88/340), Enterococcus spp. (20.9%, 71/340), and Staphylococcus aureus (15.6%, 53/340). - High resistance among Gram-positives: oxacillin 74.5% (41/55 tested), penicillin 72% (36/50 tested), vancomycin 51.1% (24/47 tested) where reported. - Gram-negative isolates showed critical resistance to commonly used agents: ampicillin 100% (24/24), ceftriaxone 92.4% (157/170), trimethoprim-sulfamethoxazole 89.4% (126/141). - Overall resistance phenotypes included **multidrug-resistant (MDR)** 43.8% (149/340), **extensively drug-resistant (XDR)** 30.5% (104/340), and pandrug-resistant (PDR) 5.3% (18/340); similar distributions were seen among ESKAPEE strains. - Independent predictors of culture positivity: male sex (female sex associated with 44% lower odds, p = 0.002); age groups with higher odds included neonates (≤28 days) with 4.7-fold higher odds (p = 0.001) and young adults (15–24 years) with 9.5-fold higher odds (p = 0.001) versus elderly patients. - Study used WHO-recommended manual blood culture processing and Kirby–Bauer disk diffusion interpreted by CLSI guidelines; statistical analysis with SPSS v20; significance at p < 0.05. - Authors recommend urgent antibiotic stewardship, revision of empirical therapy guidelines, and expanded laboratory capacity (anaerobic culture, MIC testing, molecular sequencing) to monitor and manage high AMR burden. - Data availability: all relevant data included in paper and supporting information; no specific funding declared and no competing interests reported.
## Clinical Analysis & Structured Key Points
Bacterial profile and antimicrobial resistance patterns of bloodstream infections at Amhara Public Health Institute, Bahir Dar, Ethiopia | PLOS One Browse Subject Areas ? Click through the PLOS taxonomy to find articles in your field. For more information about PLOS Subject Areas, click here . Article Authors Metrics Comments Media Coverage Peer Review Reader Comments Figures Figures Abstract Background Managing bloodstream infections in resource-constrained regions like Ethiopia is challenging due to scarce blood culture surveillance data. To guide empirical therapy, this study determines the bacterial profiles and antimicrobial resistance patterns among patients with suspected bloodstream infections at the Amhara Public Health Institute. Methods This retrospective study analyzed blood culture records from the Amhara Public Health Institute spanning January 1, 2020, to December 30, 2023. Blood samples were processed using standardized manual culture techniques in accordance with World Health Organization (WHO) protocols. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method following Clinical and Laboratory Standards Institute (CLSI) guidelines. Statistical analysis was conducted using SPSS version 20, employing descriptive statistics and regression models, with statistical significance defined as p 28 days to 14 years), and adults (≥ 15 years). Records with missing or illegible data, as well as those identified as blood culture contaminants, were excluded from the final analysis. Blood samples collection. Blood samples were collected according to standardized manual blood culture methods following WHO recommendations [ 12 ]. The pre-analytical phase of blood culture procedures have a significant impact on the sensitivity, interpretation, and clinical relevance of blood cultures. The positivity of a blood culture depends on the volume of blood, number of blood culture sets and timing of blood cultures [ 13 ]. The site of venipuncture was properly disinfected with 70% alcohol followed by 2% tincture of iodine to avoid contamination of the blood culture with skin flora. Depending on institute manual blood culture collection standard operating procedure (SOP) adults, 10 ml per bottle (two aerobic bottles), pediatrics a maximum of 5 ml per bottle (two aerobic bottles) and for neonates 1 ml per bottle (two aerobic bottles) of blood sample was drawn within a 24-hour period via separate peripheral venipuncture prior to antibiotic administration [ 14 ]. Blood culture. Following collection, blood samples were immediately transferred into blood culture bottles containing tryptone soy broth (TSB) at a standard 1:10 blood-to-broth ratio. Inoculated bottles were transported at room temperature to the laboratory within 30 minutes of collection. The bottles were then incubated at 35–37°C for up to seven days and inspected daily for macroscopic signs of microbial growth. Cultures displaying evidence of growth were sub cultured using manual blood culture systems [ 12 ]. Sub-culture of primary blood culture. Positive blood cultures were sub cultured onto blood agar plates (BAP), MacConkey agar plates (MAP), and chocolate agar plates (CAP). The BAP and CAP media were incubated under microaerophilic conditions using a candle jar at 35–37°C for 48 hours, whereas MAP media were incubated aerobically at the same temperature for 24 hours. Bacterial identification was subsequently performed based on colony morphology, hemolysis patterns, Gram staining, and standard biochemical tests. Bacteria identification. Following the isolation of pure cultures from subculture plates, bacterial identification was guided by Gram stain results. Gram-negative bacilli were characterized using a panel of conventional biochemical assays, including triple sugar iron (TSI) agar fermentation, indole production, citrate utilization, urease activity, motility, lysine decarboxylase (LDC) and oxidase testing [ 15 ]. Gram-positive bacteria were identified using conventional biochemical assays, including catalase, coagulase, bile esculin agar and mannitol fermentation, in accordance with the Clinical and Laboratory Standards Institute (CLSI) 2024 guidelines [ 16 , 17 ]. Candida spp. were identified based on macroscopic features, including colony morphology, growth rate, and surface texture, and further confirmed via microscopic examination and the germ tube test [ 7 ]. Antimicrobial susceptibility testing Antimicrobial susceptibility testing (AST) was performed for each isolate on Mueller–Hinton agar using the standardized Kirby–Bauer disk diffusion method, in accordance with the Clinical and Laboratory Standards Institute (CLSI) 2024 (M100) guidelines [ 16 ]. Bacterial suspensions were prepared, adjusted, and inoculated onto the agar surface. Gram-positive isolates were tested against chloramphenicol (30 μg), cefoxitin (30 μg), penicillin (10 units), gentamicin (10 μg) and vancomycin (30 µg). Gram-negative isolates were evaluated using ampicillin (10 µg), amoxicillin-clavulanic acid (30 μg), ceftriaxone (30 μg), ceftazidime (30 μg), chloramphenicol (30 μg), ciprofloxacin (5 μg), gentamicin (10 μg), imipenem (10 μg), meropenem (10 μg), trimethoprim-sulfamethoxazole (1.25/23.75 μg), tobramycin (10 μg) and piperacillin-tazobactam (100/10 μg). These specific antimicrobial agents were selected based on their local availability and high prescription frequency for managing bloodstream infections in Ethiopia, particularly within the study area. Following overnight incubation, zones of inhibition were measured to categorize the isolates as susceptible, intermediate, or resistant. All antibiotic disks were sourced from Oxoid Ltd. (Basingstoke, Hampshire, UK). Definitions Bacterial isolates were classified as multidrug-resistant (MDR), extensively drug-resistant (XDR), or pandrug-resistant (PDR) according to the criteria defined by Magiorakos et al [ 9 ]. Multi-drug resistance: defined as non-susceptibility to at least one agent in three or more antimicrobial classes [ 9 ]. Extensive-drug resistance: defined as non-susceptibility to at least one agent in all but two or fewer antimicrobial categories tested for a particular microorganism [ 9 ]. Pan-drug resistance was defined as non-susceptibility all to agents in all antimicrobial classes for each bacterium in this study [ 9 ]. Blood culture contamination: defined as the growth of common skin commensals in only a single blood culture set out of a series [ 18 , 19 ]. Contaminant species: included Diphtheroids (excluding Corynebacterium diphtheriae ), Bacillus spp. (excluding Bacillus anthracis ), coagulase-negative staphylococci (CoNS), Propionibacterium spp, Aerococcus spp, Micrococcus spp. and Streptococci viridans regardless of the number of positive blood culture bottles [ 18 , 19 ]. Quality control Standard operating procedures (SOPs) for blood culture processing were strictly followed across all phases including sample collection, transportation, inoculation, incubation, and biochemical identification to ensure data accuracy and reliability. Media quality control was performed by randomly selecting 5% of each prepared batch and incubating it aerobically at 35–37°C for 24 hours to confirm sterility. Media performance was further validated using standard control strains prior to inoculation and susceptibility testing. Antibiotic disks were selected based on local availability in accordance with CLSI guidelines [ 16 ]. Quality control for organism identification and susceptibility testing was maintained using reference strains, including E. coli ATCC 25922, S. aureus ATCC 25923 and P. aeruginosa ATCC 27853. Finally, senior microbiologists verified the accuracy of all inoculation techniques, colony characterizations, zone measurements, and AST interpretations. Data analysis and interpretation Statistical analysis was performed using SPSS version 20 for data entry, cleaning, coding, and modeling. Descriptive statistics, including frequencies and percentages, were calculated to summarize the study variables. To assess the strength of association between independent and dependent variables, binary logistic regression models were utilized. Variables demonstrating a p -value < 0.20 in the bivariate analysis were entered into the multivariate logistic regression model to control for confounding and identify independent associations. Statistical significance was evaluated using adjusted odds ratios (AOR) with corresponding 95% confidence intervals (CI). Finally, the data analyzed was presented using text, tables, and graphs. Ethical consideration Ethical approval for this study was granted by the regional public health research Ethical Review Committee (ERC) (Ref: NOH/R/T/D/07/74). Furthermore, permission was obtained from the institute’s laboratory director and the head of the bacteriology reference laboratory. Because the study utilized secondary, routinely collected laboratory culture data, the requirement for patient informed consent was waived by the ERC. To ensure patient confidentiality, all personal identifiers were removed, and the dataset was analyzed entirely anonymously. All relevant data was included within the manuscript and supporting information files without restriction. The study was conducted in full compliance with the ethical principles of the Declaration of Helsinki. Results Socio- demographic and clinical characteristics of study participants Between 2020 and 2023, a total of 817 blood culture records were retrieved; 141 were excluded as contaminants, leaving 676 records for the final analysis. The mean age of the participants was 15.86 years (SD ± 20.8 years; range: 1 day to 90 years). More than half of the participants were male (58.9%, N = 398). The most represented age groups were infants aged 29 days to 5 years (27.8%, N = 188), followed by neonates ( ≤ 28 days) (23.8%, N = 161). Regarding clinical management settings, most of the study participants were treated in inpatient department (89.1%, N = 602) ( Table 1 ). Download: PNG larger image TIFF original image Table 1. Socio-demographic and clinical characteristics of patients with suspected bloodstream infections at Amhara Public Health Institute, 2020-2023. https://doi.org/10.1371/journal.pone.0354710.t001 Regarding clinical indications, many participants were investigated for suspected community-acquired bloodstream infections (75.0%, N = 507), followed by hospital-acquired infections (11.7%, N = 79) and surgical site infections (3.6%, N = 24). Notably, a high proportion of the study population (78.4%, N = 530) reported a history of prior antimicrobial use. In terms of temporal distribution, the highest sample volume was recorded in 2021, accounting for 38.3% (N = 259) of the total study population ( Table 1 ). Bacteriological profiles of bloodstream infection suspected patients Out of 817 blood culture records retrieved, 58.9% (N = 481) yielded growth, while 41.1% (N = 336) showed no growth. Among the positive cultures, 29.3% (N = 141) were identified as contaminants and excluded from further analysis. These included Coagulase-negative staphylococci (CoNS) (27%, N = 130), Bacillus spp. (1.2%, N = 6) and Candida spp. (1%, N = 5). The remaining 676 blood culture records were included in the final analysis, of which 50.3% (N = 340) yielded true bacterial pathogens ( Fig 1 ). Download: PNG larger image TIFF original image Fig 1. Distribution of positive blood cultures, true bacterial isolates and contaminants at the Amhara Public Health Institute, 2020–2023. https://doi.org/10.1371/journal.pone.0354710.g001 Among the 340 true bacterial pathogens, Gram-negative bacteria were the most frequent isolates at 61.2% (N = 208), while Gram-positive bacteria accounted for the remaining 38.8% (N = 132) ( Fig 2 ). Download: PNG larger image TIFF original image Fig 2. Proportion of Gram-negative and Gram-positive bacterial isolates from patients with suspected bloodstream infections at Amhara Public Health Institute, 2020-2023. https://doi.org/10.1371/journal.pone.0354710.g002 Among true bloodstream infections, ESKAPEE pathogens accounted for 96.4% (N = 328) of isolates, driven primarily by Klebsiella spp. 25.9% (n = 88), Enterococcus spp. 20.9% (N = 71), and S. aureus 15.6% (N = 53) ( Fig 3 ). Download: PNG larger image TIFF original image Fig 3. Frequency and distribution of isolated ESKAPEE pathogens from patients with suspected bloodstream infections at Amhara Public Health Institute, 2020-2023. https://doi.org/10.1371/journal.pone.0354710.g003 Non-ESKAPEE pathogens were infrequently isolated, accounting for only 3.5% (N = 12) of the true pathogens. Among these, Citrobacter spp. and true CoNS represented 1.2% (N = 4) and 0.6% (N = 2) respectively
## Related Clinical Research

- [Genomic and antibiogram characterization of Pasteurella multocida type A from layer chickens](https://medichelpline.com/clinical-feed/plos-one-21-isolation-antibiogram-and-whole-genome-sequence-analysis-of-pasteurella.md)
- [Sales of veterinary antimicrobials in Bangladesh, 2023: volumes, classes and routes](https://medichelpline.com/clinical-feed/pubmed-42676771.md) (DOI: 10.2471/BLT.25.294366)
- [Trends in bacteraemia incidence and antimicrobial resistance, Calgary 2006–2022: genomic and presc](https://medichelpline.com/clinical-feed/medrxiv-4-trends-in-incidence-and-antimicrobial-resistance-for-five-major-causes-of.md)
- [Early oral fecal microbiota transplantation versus vancomycin or fidaxomicin for first or first-re](https://medichelpline.com/clinical-feed/bmj-open-13-fecal-microbiota-transplantation-versus-vancomycin-or-fidaxomicin-in.md)
- [Wild felids as sentinels for antimicrobial resistance: susceptible Escherichia coli in a Brazilian](https://medichelpline.com/clinical-feed/pubmed-42663762.md) (DOI: 10.1007/s11259-026-11488-7)

## Navigation
- [← Back to Infectious Disease Feed](https://medichelpline.com/clinical-feed/infectious-disease.md)
- [← All Clinical Specialties](https://medichelpline.com/clinical-feed.md)
## Medical & Regulatory Disclaimer

> [!CAUTION]
> MedicHelpline content is structured for research, educational, and professional discovery purposes. It does not constitute individual medical advice, clinical diagnosis, or treatment recommendations.
> Always verify dosing, contraindications, and regulatory alerts against official product labeling and primary regulatory sources before clinical decision-making.