Evidence map›Paper›PMID 41168248›Full record

ArticleScientific reports2025

Synergistic effects of colistin-based combinations against colistin and carbapenem-resistant Klebsiella pneumoniae isolated from nosocomial bloodstream infections.

Bahman Pourabbas, Shima Sepehrpour, Sadaf Asaei, Amin Abbasian, Parham Pourabbas, Zahra Rezaei

Abstract read
In one paragraph

Article in Scientific reports, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Article
  2. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Bahman PourabbasClinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran. bpourabbas@yahoo.com.
Shima SepehrpourClinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Sadaf AsaeiClinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Amin AbbasianClinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Parham PourabbasClinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Zahra RezaeiClinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The emergence of colistin and carbapenem-resistant Klebsiella pneumoniae (CRCR-KP) poses a critical challenge in treating bloodstream infections. As resistance reduces colistin's efficacy, alternative strategies are urgently needed. Combination therapy may offer improved outcomes, but its effectiveness remains uncertain. This study evaluated in vitro interactions between colistin and 12 commonly used antibiotics against CRCR-KP isolates from nosocomial bloodstream infections. A retrospective analysis identified 25 CRCR-KP isolates (10.8%) among 270 K. pneumoniae bloodstream infections, with 18 isolates included in synergy testing. Checkerboard assays were used to assess colistin-based interactions, quantified using the Fractional Inhibitory Concentration Index (FICI), Loewe Additivity, and Bliss Independence models. Demographic and clinical data were collected, including ward distribution, comorbidities, prior antibiotic exposure, and patient outcomes. The median patient age was 65 years (range: 2-94), and the mortality rate was 77.8% (14/18), underscoring the severity of these infections. Patients were primarily admitted to the ICU (22.2%), emergency department (33.3%), and hematology unit (22.2%), with frequent invasive procedures (94.4%) and hospital stays ranging from 4 to 60 days. 66% of isolates were classified as extensively drug-resistant (XDR). Disk diffusion and MIC testing revealed high resistance across most antibiotic classes, though tigecycline (44.4%), amikacin (50%), and minocycline (34%) demonstrated partial efficacy. Synergy detection rates varied by model, FICI (75%), Loewe (50%), and Bliss (41.6%), highlighting the importance of using multiple analytical approaches. Clindamycin, chloramphenicol, erythromycin, and minocycline exhibited strong synergy with colistin at lower concentrations, suggesting a promising combination strategy for managing CRCR-KP bloodstream infections. Minocycline appears particularly viable due to its achievable serum concentrations and moderate Gram-negative coverage. Further pharmacokinetic, pharmacodynamic, and clinical research is essential to validate these findings and guide the development of effective treatment regimens.

Indexed as

Anti-Bacterial AgentsBacteremiaCarbapenem-Resistant EnterobacteriaceaeColistinCross InfectionKlebsiella InfectionsKlebsiella pneumoniaeAdolescentAdultAgedAged, 80 and overCarbapenemsChildChild, PreschoolDrug Resistance, Multiple, BacterialDrug SynergismAnti-Bacterial AgentsCarbapenemsColistinAntibiotic synergyColistin and carbapenem-resistant Klebsiella pneumoniae (CRCR-KP)Nosocomial bloodstream infections

Identifiers

PMID41168248
PMCPMC12575765

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.