Clinical Isolates Identification of Burkholderia Species and Evaluate Their Antibiogram at a Tertiary Care Hospital

Perfil de resistencia antimicrobiana de Burkholderia cepacia en el IGSS, Guatemala de 2015 a 2019

OBJECTIVE: to characterize the resistance profile of Burkholderia cepacia during the period 2015-2019, as well as to describe the demographic and clinical characteristics of the patients from whom the B. cepacia isolates were obtained. METHOD: the study was retrospective, descriptive, cross-sectional. Statistical analysis was performed using the Kruskal-Wallis test and chi-square test. RESULTS: During the study period, 587 B. cepacia isolates were identified, with a higher percentage in males (61.8%), and the prevalence of B. cepacia infections was higher in adults (75%) compared to pediatric patients. Blood cultures yielded the highest number of B. cepacia isolates (64.3%), with an increase in resistant strains in the year-over-year distribution for most of the antibiotics evaluated. CONCLUSION: the increase in antibiotic resistance observed for most of the antibiotics evaluated represents a relevant clinical challenge requiring continuous epidemiological surveillance. The majority of infected patients were adult males, and blood cultures yielded the highest number of B. cepacia isolates.

Study of fluoroquinolones resistance genes in Acinetobacter baumannii isolated from clinical sources

Acinetobacter baumannii is a common multidrug-resistant bacteria that causes hospital-acquired illnesses. This research attempted to identify quinolone resistance genes in A. baumannii isolated from various clinical materials, including burns, blood, sputum, urine, and diabetic foot infections, with a distribution of 199 (53%) male and 176 (47%) female subjects. The bacterial culture results indicated that out of 375 specimens, 157 (41.9%) exhibited single growth, 28 (7.4%) displayed mixed growth, and 190 (50.7%) showed no bacterial growth.  This study identified 155 instances (41.33%) of gram-negative bacteria. The Vitek-2 system identified 28 isolates (7.46%) as A. baumannii. The highest isolation rate occurred in burn patients at 17 (4.53%), followed by 4 (1.07%) isolates from patients with respiratory tract infections, and 3 (0.8%) from blood source records. Diabetic foot infections and urinary tract infections were documented in two instances (0.53%). The antimicrobial susceptibility test results revealed that all 28 (100%) isolates demonstrated resistance to Cefoxitine, Ceftazidime, and Ciprofloxacin. Additionally, 27 (96.42%) of the isolates were resistant to meropenem, while 26 (92.85%) exhibited resistance to tobramycin and Ampicillin-Sulbactam. Concurrently, 89.28% of the isolates were resistant to gentamicin. The PCR analysis results indicated that the qnrA, qnrB, and qnrS genes were identified in 11 (39%), 7 (25%), and 21 (75%) of the A. baumannii isolates, respectively.

Molecular detection of carbapenemase genes in WHO priority pathogens from blood cultures of sepsis patients in Pakistan.

AIMS This study aimed to assess the antibiogram patterns of CR-GNB and to characterize carbapenemase-encoding genes among isolates obtained from patients with sepsis. METHODS A total of 3,746 blood culture samples were collected from patients with suspected septicemia and samples were processed using the BACTEC blood culture system, and all positive cultures were sub-cultured onto blood agar and MacConkey agar plates for isolation. Bacterial identification and antimicrobial susceptibility testing were performed using the VITEK 2 compact system following CLSI guidelines. Detection of antimicrobial resistance genes was carried out by PCR using gene-specific primers. RESULTS Of 3,746 blood cultures, 873 (23.3%) were positive, yielding 577 (66.1%) Gram-negative isolates. Among these, 212 (24.3%) were CR-GNB, predominantly A. baumannii (41.5%), and K. pneumoniae (21.2%). MIC of meropenem among CR-GNB isolates ranged from >128 µg/mL to <1024 µg/ml. Overall, 47.2% of isolates were inhibited at 624µg/mL, followed by 38.2% at 312 µg/mL, and 12.7% at 156 µg/ml. In CR-A. baumannii, blaOXA-23 and blaNDM were detected in 71.6% and 62.5% of isolates, respectively. blaNDM was also present in K. pneumoniae (43.8%), and E. coli (40.7%).   . CONCLUSION There was a high prevalence of CR-GNB among septicemia patients, emphasizing the need for strict infection control measures to prevent their spread.

Molecular Characterization of OXA Carbapenemase Genes in Acinetobacter Baumannii Isolated from Different Clinical Samples

Background/Aims: Acinetobacter baumannii is an opportunistic gram-negative pathogen and an increasingly important cause of hospital-acquired infections, particularly in intensive care units. Its remarkable ability to rapidly acquire resistance mechanisms, especially against carbapenems, represents a major public health concern. This study aimed to investigate the molecular detection and characterization of OXA-type carbapenemase genes in A. baumannii isolates collected from various clinical sources in Baghdad, Iraq. Methods: Between March and July 2025, 36 non-repetitive A. baumannii isolates were obtained from patients with different infections. Identification was performed using standard biochemical tests, CHROMagar Acinetobacter, and the VITEK 2 system and was confirmed by PCR amplification of the intrinsic blaOXA-51 gene. Antimicrobial susceptibility testing was conducted according to CLSI guidelines. The prevalence of blaOXA-23, blaOXA-24, blaOXA-51, and blaOXA-58 genes was determined by PCR. Selected PCR products were sequenced and subjected to phylogenetic analysis. Results: Extensive antimicrobial resistance was observed among the isolates, particularly to carbapenems, with resistance rates of 83.3% for imipenem and 72.2% for meropenem. High resistance rates were also detected for fluoroquinolones and aminoglycosides, whereas colistin and tigecycline retained comparatively greater activity. PCR screening revealed prevalence rates of 100% for blaOXA-51, 86.1% for blaOXA-23, 69.4% for blaOXA-24, and 47.2% for blaOXA-58. Multiple blaOXA genes were detected in more than half of the isolates, suggesting horizontal gene transfer and local clonal expansion. Phylogenetic analysis demonstrated high similarity between local isolates and international reference strains, supporting the widespread dissemination of resistance determinants. Several nucleotide substitutions were identified within the blaOXA-23 and blaOXA-24 genes. Conclusion: The findings indicate that blaOXA-23 is the predominant contributor to carbapenem resistance among A. baumannii isolates in Baghdad, while blaOXA-24 and blaOXA-58 are also increasingly prevalent. The observed resistance patterns and phylogenetic relationships underscore the importance of continuous molecular surveillance, antimicrobial stewardship, and effective infection control measures to limit the spread of multidrug-resistant A. baumannii. These data contribute valuable regional information to the global understanding of antimicrobial resistance epidemiology.

A study of the molecular epidemiology of nosocomial strains of Acinetobacter baumannii isolated from Nepal

Characterization of blaNDM-1 and blaOXA-23-Type Carbapenemases in Acinetobacter baumannii Isolated from Post-Surgical Patients

This study substantiates an escalated incidence of carbapenem-resistant, MDR A. baumannii in post-surgical infections in Pakistan, highlighting the exigency for strengthened antimicrobial stewardship and infection control strategies in the hospitals of the region.