Antibiotic Resistance Marker Testing

LexaGene has recently completed the development of an antibiotic resistance marker panel comprised of 12 assays targeting antibiotic resistance genes commonly found in bacterial pathogens. The development of these assays further expands LexaGene’s capabilities in providing a complete testing solution for veterinarians to understand both the cause of an infection and whether any antibiotic resistance factors are present to guide prescription decisions.

Panel details

LexaGene’s scientific team validated 12 assays targeting genes that confer resistance to penicillins (e.g. Benzyl penicillin and Amoxicillin), cephalosporins (e.g. Cephalothin and Cefotaxime), carbapenems (e.g. Imipenem), and beta lactam inhibitors (e.g. Clavulanate). The team validated the performance of these assays using 35 bacterial strains procured from the Antibacterial Resistance Leadership Group (ARLG)* that were known to carry markers that confer resistance to these antimicrobials.  The performance of LexaGene’s assays against these strains performed robustly, as expected.  The team further tested these assays on isolates from urine collected from sick dogs and have correlated 12 drug resistant samples with the presence of five different resistance genes.

The issue of antibiotic resistance

Antibiotic resistance is considered by the CDC to be one of the biggest public health challenges of our time. Each year in the U.S., at least 2 million people get an infection that is resistant to antibiotics, and at least 23,000 people die as a consequence.1  A recent clinical study saw a 1600% increase in multi drug resistant bacterial infections of the bloodstream between 1999 and 2007.2  In that same group of patients the first antibiotic used was ineffective 63% of the time.  “Superbugs”, or multidrug resistant bacteria, are becoming alarmingly common.  A recent report predicts that by 2050, antimicrobial resistant superbugs could kill an estimated 10 million people each year worldwide, overtaking cancer as a cause of death, and having a financial impact of $100 trillion USD worldwide.The need for better diagnostics is supported by a CDC summary showing that for many antibiotics, it has taken 2 or less years for resistance to emerge once the antibiotic was introduced.4 Equally frightening, new antibiotic resistance genes, that are easily transferable among bacteria, are being regularly discovered, even for last-resort antibiotics reserved for patients infected with extensively drug resistant strains.5

To lessen the probability of such an impact, new technologies are required that can quickly determine whether an infection exists so in cases where no infection is detected, healthcare providers have the confidence to hold back on prescribing a therapy.  And conversely, when an infection is confirmed, the instrument will also report on whether any antibiotic resistance factors were also detected that would potentially sway the prescription practices of the provider so they can best treat their patient.

LexaGene’s solution

To address this problem, LexaGene is nearing completion of a beta version of its fully automated easy-to-use analyzer that will identify the most common pathogens and screen for the presence of several antibiotic resistance factors within an hour of sample collection. One of LexaGene’s key markets is veterinary diagnostics, where veterinarians send collected samples to reference laboratories that report back results several days later forcing them to guess on the diagnosis and best treatment for the patient. By providing this information on-site and within an hour of seeing the patient, health providers will be able to improve the quality of care, lower healthcare costs, and hopefully over time, lead to a reduction in the incidence of infections by resistant strains.


3The Review on Antimicrobial Resistance Chaired by Jim O’Neill, December 2014


*This study is supported by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health under Award Number UM1AI104681. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.