CHROMagar™ ESBL Kit

For Overnight Detection of Extended Spectrum β-Lactamase (ESBL)-Producing Gram-Negative Bacteria

CHROMagar™ ESBL is a selective and differential chromogenic culture medium designed for the direct detection, isolation, and differentiation of ESBL-producing Enterobacteriaceae and other Gram-negative bacteria from clinical specimens. It enables overnight detection (18–24 hours) with distinctive colony coloration for key species such as E. coli, Klebsiella spp., Enterobacter spp., and Pseudomonas spp.

Built upon the chromogenic performance of CHROMagar™ Orientation, this enhanced medium contains selective agents that suppress non-ESBL and most AmpC-expressing organisms, improving specificity while preserving high sensitivity. It is ideal for ESBL colonization screening, surveillance, and early outbreak detection in healthcare and public health settings.

🔹 Key Features & Benefits

• ✅ Rapid Results: Detection of ESBL-producing bacteria in 18–24 hours—no pre-enrichment required.
• ✅ Color-Based Species Differentiation:

  Organism	Colony Appearance
  ESBL E. coli	Dark pink to reddish
  ESBL Klebsiella/Enterobacter/Citrobacter	Metallic blue ± red halo
  ESBL Proteus spp.	Brown halo
  ESBL Pseudomonas spp.	Translucent cream to blue
  ESBL Acinetobacter spp.	Cream, opaque

• ✅ High Sensitivity and Specificity: Designed to detect ESBL mechanisms (e.g., blaCTX-M, blaSHV, blaTEM) while inhibiting most AmpC-producing strains, reducing false positives.
• ✅ Direct-from-sample Screening: Streamlines workflow by eliminating the need for selective enrichment broths.
• ✅ Versatile Use: Suitable for patient screening (rectal/stool swabs) and early infection detection in hospital outbreaks or routine surveillance.
• ✅ Long Shelf-Life: Over 18 months stability for batch flexibility and preparedness during epidemics.

🔹 Intended Use

CHROMagar™ ESBL is intended for:

• Qualitative detection of gastrointestinal colonization with ESBL-producing Gram-negative bacteria
• Routine screening of high-risk patients in ICUs, oncology wards, transplant units, and long-term care facilities
• Surveillance testing during outbreaks or epidemiological studies

⚠️ Not intended to diagnose infections or guide treatment. Further confirmatory testing (e.g., MALDI-TOF, PCR, susceptibility testing) is required for clinical management.

🔹 Clinical Background

ESBL-producing organisms hydrolyze extended-spectrum cephalosporins (e.g., ceftriaxone, ceftazidime) and monobactams, posing serious challenges in infection management. Key features of ESBL spread include:

• Plasmid-mediated resistance that can be easily transferred between bacteria
• Misidentification or missed detection in standard AST panels
• Escalation in carbapenem use, leading to further multidrug resistance

📌 Early detection of ESBL colonization is essential to prevent nosocomial transmission and guide infection control measures.

🔹 Test Procedure

1. Sample Types: Rectal swabs, stool samples, clinical fecal specimens
2. Inoculation: Direct streaking on CHROMagar™ ESBL
3. Incubation:
   • Temperature: 35–37 °C
   • Time: 18–24 hours
   • Atmosphere: Aerobic
4. Interpretation: Based on colony color and morphology to presumptively identify ESBL-producing species

🔹 Ordering Information

🔹 Storage & Shelf Life

• Storage Conditions: 2–8 °C, sealed, dry
• Shelf Life: Up to 18–24 months
• Prepared Media: Follow manufacturer guidelines for use-by date

🔹 Scientific Publications

• Gonzales-Escalante et al., 2023 – Detection of ESBL-producing E. coli in poultry, Peru
• El Aila et al., 2023 – Molecular detection of blaTEM, blaSHV, and blaCTX-M in pediatric isolates
• Hammood & Ibrahim, 2022 – ESBL-producing bacteria in aquatic environments

CHROMagar™ ESBL is a rapid, selective, and highly visual medium that allows for the direct detection of ESBL-producing Gram-negative pathogens from patient and environmental samples. Its color-coded differentiation, high specificity, and workflow efficiency make it a vital tool for infection control teams, public health laboratories, and hospital microbiology units involved in the global effort to curb antimicrobial resistance.