Peer-reviewed veterinary case report
How heartworm test accuracy and treatment affect suspected prevention
By Rohrbach, B W & Patton, S·Published in Journal of veterinary internal medicine·2013·Department of Biomedical and Diagnostic Sciences, United States·View original on PubMed →
PetCaseFinder translated the abstract of this peer-reviewed paper into plain English so pet owners can read it. We do not publish original research — every detail traces back to the citation above. How we work →
Original publication title: Effects of diagnostic test accuracy and treatment efficacy on the occurrence of suspected failure of heartworm prophylaxis in dogs.
- Species:
- dog
Plain-English summary
A study looked at how accurate heartworm tests are and how effective the treatment is for dogs suspected of having heartworms despite being on prevention. The heartworm antigen test was found to be quite reliable, with a high chance of correctly identifying dogs without heartworms. However, some dogs may still test positive for heartworms even if they were on prevention, leading to confusion about treatment effectiveness. The researchers emphasized that vets should consider the dog's history and local heartworm prevalence when interpreting test results and discussing treatment options with pet owners.
People also search for: dog heartworm test accuracy · heartworm treatment for dogs · why did my dog test positive for heartworms on prevention
Abstract
BACKGROUND: Food and Drug Administration Center for Veterinary Medicine (FDA/CVM) cited concern regarding failure of heartworm prophylaxis. The positive and negative predictive value of the heartworm antigen test is an estimate of the probability of adult heartworm infection. HYPOTHESIS/OBJECTIVES: Assess the sensitivity, specificity, and predictive value of heartworm antigen tests. Explore the role of heartworm test accuracy and treatment with immiticide to generate reports of suspected failure of heartworm prophylaxis. METHODS: Literature searches for published information on the accuracy of heartworm antigen tests and efficacy of immiticide for treatment of the adult heartworm. RESULTS: Weighted averages for heartworm antigen test sensitivity and specificity were 78.2 and 97.3%, respectively. Efficacy of immiticide by 2-injection or alternate dose protocols were 88.3 and 89.1%, respectively. Depending on prevalence, the positive predictive value of the heartworm antigen test ranged from 15 to 54% and negative predictive value from 99 to 99.9%. For a hospital testing 1,000 dogs per year, false-positive test results may vary from 24 to 27 dogs. If these dogs were on heartworm preventive, they may undergo treatment and be classified as prophylaxis failures. Ten percent of dogs who were treated and continued or placed on prophylaxis at the time of treatment may have adult heartworms when tested 1 year later and be presumed to represent failure of prophylaxis. CONCLUSIONS: When interpreting heartworm antigen test results, clinical signs, history, and regional prevalence of heartworm disease should be considered in estimating the predictive value of the test result. Limitations of test and treatment should be discussed with clients as part of the decision-making process.
Find similar cases for your pet
PetCaseFinder finds other peer-reviewed reports of pets with the same symptoms, plus a plain-English summary of what was tried across them.
Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/23663198/