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Axel Hamprecht

Publications and source records attributed to Axel Hamprecht.

2 recordsLinked to original sources
PubMed2026

Performance of seven carbapenemase detection assays in Pseudomonas aeruginosa across different epidemiological settings: a multicenter cross-sectional study.

The detection of carbapenemases in Pseudomonas aeruginosa remains challenging due to a great variety of other resistance mechanisms, and most laboratories, therefore, do not test for them. This study aimed to comparatively evaluate seven phenotypic carbapenemase detection assays across three epidemiological settings. A total of 320 P. aeruginosa isolates from three German centers with varying carbapenemase prevalences (5.8%-51.4%), including 113 carbapenemase-producing isolates carrying VIM-2 (n = 58), NDM-1 (n = 19), and GIM-1 (n = 16), underwent whole-genome sequencing as reference to assess seven phenotypic carbapenemase-detection tests: modified- and modified-zinc-supplemented carbapenem inactivation method (mCIM and mzCIM), simplified carbapenem inactivation method (sCIM), Carba NP, imipenem-cloxacillin test (IC-4000), and two imipenem-EDTA disk assays. Of all confirmation assays, mzCIM and sCIM showed the best overall performance for carbapenemase detection (sensitivity/specificity: 100%/94.2% and 99.1%/92.8%), followed by mCIM (93.8%/96.1%). Carba NP achieved the highest specificity (99.0%), but the lowest sensitivity (85.8%). EDTA-based assays and IC-4000 were highly sensitive (96.5%-100%) but less specific (79.7%-87.0%). Negative predictive values were consistently high (≥98%-100%) across all assays and prevalence settings, whereas positive predictive values varied (72.5%-98.0%). Both mzCIM and sCIM exhibited robust performance for carbapenemase detection in P. aeruginosa, representing the most suitable approach across diverse epidemiological settings. Their high negative predictive values indicate that these assays are particularly effective for ruling out carbapenemase production. Furthermore, both assays are cost-effective, simple to perform, and can be readily implemented in any routine microbiology laboratory.IMPORTANCEThis study provides comparative diagnostic accuracy data for seven phenotypic carbapenemase detection assays in Pseudomonas aeruginosa (PA) across different prevalence settings. Modified-zinc-supplemented carbapenem inactivation method (mzCIM) and simplified carbapenem inactivation method (sCIM) are the most robust screening tools and show that local carbapenemase-producing P. aeruginosa (CP-PA) prevalence substantially influences the utility of all evaluated assays.

CIM↗
PubMed2026

Moraxella species isolated from blood cultures in Europe (MORAXEu): a multicentre study of epidemiology and antimicrobial susceptibility with complementary phylogenomic analysis of publicly available genomes.

INTRODUCTION: Moraxella species are fastidious Gram-negative bacteria capable of causing opportunistic infections, including bloodstream infections, especially in immunocompromised patients. Data on their epidemiology, antimicrobial susceptibility, and phylogenomics in Europe remains limited. METHODS: We conducted a multicentre, retrospective, observational study across 56 European hospital centres between January 1st 2020 and December 31st 2024. All Moraxella species isolated from blood cultures (BCs) were included. Species distribution and antimicrobial susceptibility profiles were analysed. We also performed a phylogenomic analysis of Moraxella genomes deposited in GenBank. RESULTS: A total of 709 Moraxella isolates were included. Moraxella osloensis (61.1%; n = 433/709) and Moraxella catarrhalis (20.4%; n = 145/709) were the most frequently identified species, followed by Moraxella nonliquefaciens (6.5%; n = 46/709) and Moraxella atlantae (4.8%; n = 34/709). Species distribution differed by age. M. catarrhalis was predominant in paediatric patients, whereas M. atlantae was more common in adults. Most isolates showed > 90% susceptibility to amoxicillin/clavulanate, cefotaxime, fluoroquinolones, and trimethoprim/sulfamethoxazole. Cefotaxime resistance in M. osloensis was more frequent in adults than in children (49% vs. 8%, p = 0.009). Phylogenomic analysis demonstrated the distinction of a core Moraxella group from the divergent Faucicola lineage, with M. osloensis and M. atlantae clustering within the latter. CONCLUSIONS: The epidemiology of Moraxella species from BCs in Europe showed age-group-specific differences in species distribution and generally favourable antimicrobial susceptibility patterns. Phylogenomic data corroborated recent taxonomic revisions, highlighting the need for improved diagnostics, harmonized nomenclature and sustained surveillance to inform management and stewardship of Moraxella bacteraemia.

Faucicola↗