Red Rover, Red Rover, Send PCR Testing Over

by | Jan 14, 2022 | Veterinary Diagnostics

Home » Veterinary Diagnostics » Red Rover, Red Rover, Send PCR Testing Over

One might ask, is PCR testing better than cell culture?

And one might get the answer that’s not even comparing apples to oranges. It’s apples to pumpkins! Though, in a limited yet vital subset for diagnosing infection in companion animals, we can directly compare each of these techniques to diagnose the presence of specific bacteria. More importantly, we can use PCR testing to look for antibiotic resistant markers, fingerprints, on each of the bacteria.

Why does the fingerprint of AMR matter?

An AMR genetic marker is a tiny section of the bacterial DNA strand that has evolved to confer a resistant mechanism to one or more of the five classes of antibiotics that are commonly used to fight infection. This marker acts much like a rattlesnake’s tail – a small but powerful defense strategy.

The world is rapidly running out of effective antibiotics due to the increase in bacterial evolution towards antibiotic resistance, and there are multiple stewardship strategies which can slow this down.

One of these is early selection of the correct antibiotic to treat an infection.

PCR (Polymerase Chain Reaction)

LexaGene has developed a one-of-a-kind ‘Keurig-like’ MiQLab™ System that uses PCR to test for these markers in-clinic. To demonstrate the absolute accuracy and power of PCR, our scientists compared the identities of bacteria in a known sample against the exact same sample sent to a commercial reference lab. A MiQLab runs a test in approximately two hours, at the point-of-care, by anyone who has received about an hour of training. It’s that easy.

Culture and Sensitivity Testing (C&ST)

In contrast cell culture work (aka culture and sensitivity testing) is performed in a highly specialized ‘reference’ lab using trained personnel. Samples are often shipped off-site to a reference lab providing an administrative layer of both transportation and receiving. Reference lab staff must be trained to perform high-precision manual agar plating, work under controlled growth conditions, and complete optical recognition of different bacteria. After these complex steps have been done, additional plating must occur with the presence of different antibiotic infusions to determine the resistance of a bacterial strain to an antibiotic. This process can take up to two weeks including shipping and handling. Mistakes are frequent due to human error in the sample preparation as well as shipping. The lengthy time to answer delays the prescription of the correct antibiotic.

PCR testing
Researcher holding agar plate with bacterial colonies

LexaGene’s study demonstrated:

  • MiQLab successfully detected two bacterial strains in polymicrobial samples in ~2 hours
  • Culture and Sensitivity Testing (C&ST) failed to detect equivalent minor pathogen population in individual mixed samples, with final test results taking between 5 – 11 days
  • In-clinic MiQLab testing can improve treatment decisions, particularly for polymicrobia infections caused by drug resistant strains.

Download the complete study, MiQLab Bacterial and AMR Testing vs Commercial Culture and Sensitivity for Detection of Pathogens in Polymicrobial Samples

<a href="https://lexagene.com/author/dianestewart/" target="_self">Dr Diane Stewart</a>

Dr Diane Stewart

Diane Stewart has a PhD in chemistry from Brown University, and has had a lengthy career as scientist and manager for numerous scientific instrumentation products including molecular diagnostics instrumentation, nanotechnology, and ion microscopy. Currently she is the product manager for the MiQLab point-of-care system at LexaGene. She has extensive experience in federal grant writing, negotiating and administration. In addition to program and product management, she is skilled with in-house legal duties have included drafting invention disclosures, tracking patent office actions, patent searching, patent landscape analysis, leading intellectual property review boards, and negotiating legal documentation for collaborations.

Survey Says Veterinarians Have an Appetite for In-Clinic Diagnostic Technology

This spring LexaGene conducted a market research survey in conjunction with AAHA to assess the opinions of practicing veterinarians on AMR stewardship and the use of antibiotics in the treatment of companion animals.

The Dawn of the Superbugs

The most menacing of all resistant bacteria are the so called “super bugs”- strains of bacteria that are resistant to several different classes of antibiotics or multidrug resistant.

LexaGene offers North Shore Technology Council (NSTC) and Leadership Team at MassBio a tour of our Beverly Facility

Recently, we welcomed members of North Shore Technology Council and MassBio Leadership Teams into our facility at 500 Cummings Center for a full tour of our office space and laboratory spaces.

Upcoming Events

LexaGene will be exhibiting AAHA's Connexity Event in September.
1 2 3 8

Latest Resources


In this video, we detail the workflow on how to prepare and load urine and swabbed samples into our cartridge for sample processing on the MiQLab® System.
1 2 3 27