SYNDROME BASED GUIDANCE (NG-TEST VET DIRECT ESBL) This document provides practical, syndrome-based guidance for small-animal veterinarians, practice managers, and veterinary technicians when the NG Biotech point-of-care (POC) rapid test NG-TEST® Vet Direct ESBL detects an extended-spectrum beta- lactamase (ESBL) directly in a canine or feline urine sample. A positive result is a clinically meaningful signal — not a diagnosis in isolation — and it should immediately influence antimicrobial decision-making while confirmatory culture and susceptibility (C&S) testing is pursued. The guidance presented here is designed to be non-alarmist, evidence-based, and actionable. It addresses how to interpret the test result in the context of the full in-clinic diagnostic algorithm, when it is appropriate to defer treatment versus initiate targeted empiric therapy, and why beta-lactam antimicrobials should be avoided when an ESBL is detected. Clinicians are encouraged to approach a positive result as a stewardship opportunity: an early risk-stratification tool that enables more informed and responsible prescribing from the outset of case management. Prepared by Dr Shelley Rankin, Emeritus Professor of Microbiology DEFINITIONS ESBLs: Extended-spectrum beta-lactamases (ESBLs) are enzymes produced by certain Gram-negative bacteria—most commonly Escherichia Coli and Klebsiella Pneumoniae—that confer resistance to a broad range of beta-lactam antibiotics, including penicillins and third-generation cephalosporins. These enzymes inactivate antibiotics by hydrolyzing the beta-lactam ring, rendering them ineffective. The prevalence of ESBL-producing organisms in veterinary medicine is increasing, which complicates therapeutic decision-making and limits effective treatment options. CTX-M: A group of extended-spectrum beta-lactamase (ESBL) enzymes produced by certain bacteria that confer resistance to many beta-lactam antibiotics (e.g., penicillins and cephalosporins). CTX-M enzymes are currently the most prevalent ESBL type identified in companion animals (dogs and cats) and are commonly associated with multidrug-resistant infections, requiring antibiotic selection based on susceptibility testing. C&S (Culture & Sensitivity): A laboratory test in which a sample (e.g., urine) is cultured to identify the microorganism causing an infection, then tested against different antibiotics to determine which treatments are effective. NEGATIVE: If only one red line appears on the control region (C): the sample does not contain any CTX-M enzyme or non-detectable level of this one and must be interpreted as a negative result. ESBL Not Detected: Standard empiric treatment protocol. POSITIVE: If two red lines appear, one on the control region (C) and one on the test region (T), the sample contains CTX-M enzyme(s) and must be interpreted as a positive result. ESBL Detected: • Send urine for Culture and Sensitivity testing • Avoid all beta-lactams antibiotics (e.g. amoxicillin, amoxicillin-clavulanic acid, cefpodoxime) • Consider non beta-lactam treatment alternatives (as for example nitrofurantoin, or trimethoprim sulfamethoxazole (TMS) based on clinical presentation) while waiting for C&S Sensitivity 97.04%, Specificity 99.43%, PPV 95.1%, NPV 99.68% (human data4 • If possible, consult with a specialist familiar with species/disease/ESBLs (e.g. DACVIM, DACVM) ) References: 1. Hewson et al. Antimicrobial stewardship in animal health: Experience-based co-design framework to capture progress and accelerate improvement. Antimicrob Resist, Volume 1 , 2026 e1 DOI: https://doi.org/10.1017/S2977755026100015 2. Weese et al. ACVIM Consensus Statement on Therapeutic Antimicrobial Use in Animals and Antimicrobial Resistance. J Vet Intern Med 2015 Mar-Apr;29(2):487-98. doi: 10.1111/ jvim.12562. Epub 2015 Mar 17 3. Weese et al. International Society for Companion Animal Infectious Diseases (ISCAID) guidelines for the diagnosis and management of bacterial urinary tract infections in dogs and cats. Vet J . 2019 May:247:8-25. doi: 10.1016/j.tvjl.2019.02.008. Epub 2019 Feb 26 4. Volland et al. Rapid detection of CTX-M-type ESBLs and carbapenemases directly from biological samples using the BL-DetecTool. J Antimicrob Chemother 2022; 77: 2867–2875 Jorgensen Laboratories, LLC 800.525.5614 | fax 970.663.5042 www.jorvet.com | [email protected]
