Why PCR Testing for Clostridium perfringens in Dogs is of Limited Diagnostic Value Clostridium perfringens is an anaerobic, spore-forming bacterium frequently found in the environment and as part of the normal gastrointestinal microbiota of dogs. Although certain strains are capable of producing enterotoxins associated with gastrointestinal signs, PCR testing for C. perfringens toxin genes in fecal samples offers limited diagnostic utility, particularly when performed without full clinical context. A foundational study by Goldstein et al. (2012) evaluated fecal samples from both healthy and diarrheic dogs, using culture, PCR, and ELISA to assess the presence of C. perfringens and its enterotoxins. They found no statistically significant correlation between the presence of toxin genes and clinical disease, concluding that C. perfringens was a common finding in both healthy and ill dogs [PMID: 23277693]. Similarly, Marks et al. (2002) reported that C. perfringens enterotoxin (CPE) was detected in both healthy and diarrheic dogs, although more frequently in diarrheic dogs. Importantly, however, toxin gene presence alone was not a reliable predictor of disease severity or outcome [PMID: 11820110]. Chia et al. (2018) highlighted that netF-positive C. perfringens strains were also found in both diseased and healthy dogs, challenging earlier assumptions that this gene was specific to necrotizing enteritis [PMID: 29153812]. Other studies have similarly shown that the cpe gene can be present in dogs with no gastrointestinal signs, further weakening the case for using PCR as a diagnostic marker in isolation. Risks of Misinterpretation and Overuse of Antibiotics PCR is an extremely sensitive method capable of detecting low levels of bacterial DNA, even from dead organisms or non-pathogenic strains. In the case of C. perfringens, this sensitivity becomes a double-edged sword: detecting a gene does not indicate active toxin production, bacterial overgrowth, or disease causation. When PCR testing is done without proper clinical oversight, it can lead to misinterpretation of results, unnecessary anxiety for pet owners, and inappropriate antimicrobial use. The use of antibiotics in dogs with positive PCR results but no clinical evidence of C. perfringens-related disease risks harming the patient’s gut microbiota and contributes to the growing problem of antimicrobial resistance (AMR). As emphasized by Weese (2011) in a review on gastrointestinal infections, C. perfringens is an inconsistent and unreliable pathogen in dogs, with toxin detection being more informative than gene presence alone [PMID: 21461190]. Misuse of PCR results can delay proper diagnosis, compromise animal welfare, and contribute to public health risks through resistance gene propagation. Clinical Best Practices Accurate diagnosis of gastrointestinal disease in dogs must be based on thorough clinical examination, patient history, and when appropriate, supportive diagnostics such as fecal cytology, toxin ELISA, or histopathology. The detection of C. perfringens toxin genes by PCR may be a piece of the puzzle, but it should never be used in isolation to guide treatment. References Goldstein MR, Kruth SA, Bersenas AM, Holowaychuk MK, Weese JS. Detection and characterization of Clostridium perfringens in the feces of healthy and diarrheic dogs. Can J Vet Res. 2012 Jul;76(3):161–165. [PMID: 23277693] Marks SL, Kather EJ, Kass PH, Melli AC. Genotypic and phenotypic characterization of Clostridium perfringens and Clostridium difficile in diarrheic and healthy dogs. J Vet Intern Med. 2002 Jan-Feb;16(1):533–540. [PMID: 11820110] Chia MY, Hsu YM, Pang VF, Chang CC, Chang CH, Chen CM. Isolation and characterization of netF-positive Clostridium perfringens from dogs and cats in Taiwan. Vet Microbiol. 2018 Jan;214:77–82. [PMID: 29153812] Weese JS. Bacterial enteritis in dogs and cats: diagnosis, therapy, and zoonotic potential. Vet Clin North Am Small Anim Pract. 2011 May;41(3):287–309. [PMID: 21461190]

The Need for Regulation and Accountability in Pet Sample Testing Laboratories in the UK In recent years, there has been a growing concern among veterinary professionals regarding the increasing number of pet owners who bring parasite reports from unregulated and non-registered laboratories. This issue is particularly alarming in the field of exotic pet medicine, where accurate diagnosis and treatment are critical for both animal welfare and public health. These laboratories, often run by unqualified individuals with no clinical experience in the veterinary field, are providing results that frequently make no sense, sometimes listing parasites that do not even exist in the species being tested. As a result, general practitioners are unknowingly basing treatment decisions on faulty data, leading to unnecessary or incorrect treatments that can cause significant harm to the animals involved. The veterinary profession operates within a framework designed to ensure the highest standards of animal care, guided by institutions such as the Royal College of Veterinary Surgeons (RCVS), the British Veterinary Association (BVA), the Veterinary Defence Society (VDS), and Trading Standards. Registered laboratorties that test pet samples in the UK are registered with the Royal College of Veterinary Surgeons (RCVS) or ISO regulated. This makes them accountable. However, the rise of these unregulated laboratories poses a serious challenge to maintaining these standards. A formal complaint is now being submitted to these bodies, along with a request for legislative changes, to bring accountability and oversight to the testing of pet samples. This change is not only necessary to protect animal welfare but also to safeguard public health from zoonotic diseases that could be misidentified or overlooked due to poor-quality testing. The Impact of Unregulated Laboratories on Veterinary Practice The issue of unregulated parasite testing is particularly prevalent in exotic pet medicine. Unlike common domestic pets such as cats and dogs, exotic species have unique parasitological profiles, requiring specialist knowledge to correctly identify and interpret test results. In daily veterinary practice, we are seeing an increasing number of owners presenting laboratory reports from non-registered testing facilities, often obtained at a lower cost than tests conducted by veterinary-approved laboratories. These reports frequently list parasites that are not found in the species being tested or misidentify normal commensal organisms as dangerous parasites, leading to unnecessary alarm and inappropriate treatment. The consequences of relying on these inaccurate reports are severe. In our own practice, we have followed and retested a dozen cases where non-registered laboratories had reported the presence of parasites that, upon further investigation, were proven to be false positives or misidentifications. In some cases, veterinarians, trusting the initial reports, administered unnecessary deworming treatments, antibiotics, or even more aggressive interventions, causing stress and harm to the animals. Beyond the direct impact on animal health, there is also a wider issue of trust in the veterinary profession. When pet owners believe they have received accurate diagnostic information from these non-registered labs, they may question their veterinarian's recommendations when discrepancies arise. This erodes the veterinarian-client relationship and can lead to owners making misinformed decisions about their pets' healthcare. The Public Health Risk Misdiagnosing parasites does not just affect the animals involved; it also has serious implications for public health. Some parasites are zoonotic, meaning they can be transmitted from animals to humans. If an unregulated laboratory incorrectly categorizes a parasite, the risks to human health can be severe. For instance, an exotic pet owner might be falsely reassured that their animal is free from zoonotic parasites when, in reality, the pet is carrying an undiagnosed risk to its owners. Conversely, false positives may lead to unnecessary fear and the inappropriate use of medications, potentially contributing to antimicrobial resistance. Regulated veterinary laboratories adhere to strict quality control measures, ensuring that their diagnostic methods are accurate and validated. This is not the case for unregistered labs, which may lack standardized procedures, fail to follow proper sample handling protocols, and use unreliable identification techniques. The margin for error in parasite identification is small, and without ay form of accountability or level of expertise, these unregulated reports become more of a hazard than a help. The Role of Social Media and Charities in Spreading Misinformation A major driver of the problem is the role of social media groups, online forums, and even some pet charities and associations in promoting these unregistered laboratories. Many pet owners turn to these platforms for advice, unaware that the recommendations they receive may not be based on sound scientific principles. In an effort to save money, owners opt for cheaper tests from these dubious sources, not realizing that they may end up paying more in the long run due to incorrect diagnoses and inappropriate treatments. Charities and associations that recommend these unregulated testing services may be doing so with good intentions, believing they are helping pet owners find affordable testing options. However, without proper scrutiny of the laboratories they endorse, they are inadvertently contributing to the spread of misinformation and the harm it causes to both animals and their owners. The Need for Regulatory Change To address this growing issue, we are submitting a formal complaint and request for regulatory change to the RCVS, BVA, VDS, and Trading Standards. Our primary objectives are: Mandatory Registration of Laboratories: Any laboratory offering diagnostic services for pets in the UK should be required to register with an official regulatory body and adhere to strict quality control standards. Certification of Personnel: Individuals conducting testing and reporting should be required to have verifiable qualifications in the veterinary field and laboratory diagnostics. Clear Legal Consequences for Misdiagnosis: Laboratories that provide incorrect or misleading results should be held accountable, with clear legal consequences to prevent further harm to animals and the public. Public Awareness Campaign: Veterinary associations and professional bodies should launch educational campaigns to inform pet owners about the risks of using non-registered laboratories and the importance of obtaining diagnostic tests from reputable sources. Stricter Oversight of Online Advertising: Non-registered laboratories should not be permitted to advertise their services on social media platforms or be endorsed by charities and associations without proper vetting. Conclusion The rise of unregulated pet testing laboratories is a significant and growing problem in the UK. By prioritizing affordability over accuracy, pet owners are unknowingly placing their animals at risk and contributing to a larger public health issue. The veterinary profession, supported by regulatory bodies, must take a stand against these practices to ensure that all diagnostic testing meets the necessary standards of accuracy and reliability. Without swift and decisive action, the continued proliferation of these non-registered laboratories will lead to further animal suffering, increased public health risks, and a deterioration of trust between veterinarians and pet owners. We urge the RCVS, BVA, VDS, and Trading Standards to take immediate steps to implement stricter regulations, ensuring that all pet diagnostic laboratories operate with the expertise, accountability, and oversight necessary to protect both animal and human health.

Coccidia in Bearded Dragons in the United Kingdom

Campylobacter is a bacteria that can cause gastrointestinal symptoms commonly in dogs. Campylobacter in reptiles is thought to be more common than we actually think, acting as reservoirs that can then infect people or dogs.