Carba 5

NG-Test CARBA-5 for the detection of carbapenemase enzymes expressed by CPOs

June 18, 2025

This evaluation explores how the University Hospital of Wales replaced the Cepheid CARBA-R assay with the NG-Test CARBA-5 – an innovative, cost-effective lateral flow test that delivers rapid and accurate detection of carbapenemase-producing organisms (CPOs). By improving turnaround times and sensitivity, particularly for hard-to-detect IMP variants, the CARBA-5 has enhanced diagnostic efficiency and strengthened infection prevention strategies across clinical settings.

Read the evaluation here

Summary:

The poster presents a verification study of the NG-Test CARBA-5, a rapid lateral flow assay for detecting carbapenemase-producing organisms (CPOs). These enzymes render key antibiotics ineffective and pose a major public health risk.

Compared to the existing Cepheid CARBA-R molecular test used at the University Hospital of Wales (UHW), CARBA-5 offers:

  • Faster results (15 minutes vs. 50 minutes),
  • Lower cost (£16.15 vs. £18.85 per test + £264.25 for controls),
  • Higher sensitivity (100% vs. 82%),
  • Equal specificity (100%).

Study Phases:

  1. Phase 1: Verified CARBA-5 accuracy on 5 known CPO strains (VIM, NDM, KPC, OXA-48, IMP).
  2. Phase 2: Compared CARBA-5 and CARBA-R on 25 patient samples, including a blind panel and real-time lab samples. SACU (Specialist Antimicrobial Chemotherapy Unit) PCR results were used as the gold standard.

Key Findings:

  • CARBA-5 correctly detected all major carbapenemases, including difficult-to-detect IMP variants that CARBA-R missed.
  • CARBA-5 failed to detect GES (not a target), but this was consistent with expectations.
  • CARBA-5 outperformed CARBA-R in detecting certain IMP-producing organisms (e.g., IMP-8 and IMP-14), which CARBA-R is known to miss.
  • All non-CPO samples gave negative results as expected.

Conclusion:

The NG-Test CARBA-5 is a rapid, accurate, and cost-effective replacement for the CARBA-R in routine testing at UHW. It enhances infection prevention efforts by enabling faster detection of CPOs, which is crucial for patient management and outbreak control.