# A Retrospective Study on the Antimicrobial Susceptibility Patterns of Elizabethkingia meningoseptica Specimens Among Adult Patients

## TL;DR

This study analyzed antibiotic resistance patterns of Elizabethkingia meningoseptica in hospitalized adults, finding high resistance to most drugs but notable sensitivity to minocycline, levofloxacin, and imipenem.

## Contribution

The study provides updated antimicrobial susceptibility data for E. meningoseptica in a hospital setting, highlighting resistance trends and effective treatment options.

## Key findings

- Blood and endotracheal tube samples were the most common sources of E. meningoseptica isolates.
- Minocycline showed the highest sensitivity (71.2%), while resistance to aztreonam and ceftriaxone was 100%.
- Over 80% of isolates were resistant to most antimicrobials, with no sensitivity observed to colistin.

## Abstract

Background and objectives: Elizabethkingia meningoseptica has evolved as one of the emerging and multidrug-resistant organisms globally. We planned this study to evaluate the antimicrobial susceptibility testing (AST) patterns of E. meningoseptica isolates in our hospital. We also gauged the AST patterns of the isolates from various samples and patients with short (i.e., ≤ 28 days) and prolonged (i.e., > 28 days) hospitalization.

Methods: This retrospective study was conducted from August 2023 to July 2025 at Kalinga Institute of Medical Sciences (KIMS), Bhubaneswar, India. We analyzed the data of all adult inpatients with positive culture reports for E. meningoseptica. All specimens (blood, endotracheal tube (ETT), urine, sputum, wound, pus, body fluid, and skin swabs) were analyzed to evaluate the AST findings of the concerned pathogen. The subgroup analyses were done as per the sample (i.e., blood, ETT, and others) and length of hospitalization (≤ 28 and > 28 days). We illustrated the collected data via mosaic and chord diagrams. The VITEK 2 system was employed for evaluating AST. We used R software (version 4.5.2) for data analysis.

Results: We assessed 208 samples that were positive for E. meningoseptica isolates. The median age of the study population was 62.0 (46.0-71.0) years. Male patients were predominant in our study (133, 63.94%). Blood (109, 52.40%) and ETT (63, 30.29%) were the most frequently positive samples for E. meningoseptica. Thirty-six (17.31%) of the positive samples came from urine, skin swabs, sputum, nasal swabs, wounds, and pus. The average length of stay in the hospital was 22.0 (14.0-33.0) days. A total of 72 participants (34.62%) endured more than 28 days in the hospital. Of the 208 individuals, 65 (31.25%) died, and 143 (68.75%) were discharged. The isolates demonstrated the highest sensitivity towards minocycline (148, 71.2%), followed by levofloxacin (87, 41.8%) and imipenem (84, 40.4%). No sample exhibited colistin sensitivity. Over 80% of the samples showed resistance to most antimicrobials. For ceftriaxone and aztreonam, the resistance was 100%. Drug resistance to minocycline was the lowest (48, 23.1%). The subgroup analyses were similar.

Conclusion: Blood and ETT samples accounted for the majority of E. meningoseptica isolates. The isolates were highly sensitive to minocycline, levofloxacin, and imipenem. The isolates were more resistant to aztreonam, ceftriaxone, piperacillin-tazobactam, and amikacin, in contrast to other antibiotics.