title: Commercially Available Enzyme-Linked Immunosorbent Assay and Polymerase Chain Reaction Tests for Detection of Feline Immunodeficiency Virus Infection.
abstract: BACKGROUND
  Feline immunodeficiency virus (FIV) infection is an important cause of disease of cats worldwide. Initial screening is commonly performed by commercially available point-of-care (POC) ELISA tests. Confirmatory testing for positive POC test results is recommended. Polymerase chain reaction (PCR) tests for FIV are commonly used additional testing methods; however, reported measures of diagnostic accuracy vary widely between PCR tests, making interpretation of results difficult.
  
  
  OBJECTIVE
  There is very good agreement between results of a commercially available PCR test and a POC ELISA test for FIV for specimens collected from owned and shelter-housed cats.
  
  
  METHODS
  Blood samples from 168 cats from 2 adoption guarantee shelters, an FIV Sanctuary, and 64 private homes were used.
  
  
  METHODS
  This was a prospective study. Whole blood samples were collected in K2-EDTA, divided, and submitted for PCR and ELISA testing. Follow-up whole blood samples were collected in lithium heparin from cats with discordant results and submitted for virus isolation (VI).
  
  
  RESULTS
  There was very good agreement between ELISA and PCR (kappa 0.87; P < .001; 95% CI 0.79, 0.95). Of 168 cats, eleven had discordant ELISA/PCR results: 7 ELISA+/PCR- and 4 ELISA-/PCR+. Using VI as a reference standard, there were 4 false-positive PCR results, 5 false-positive ELISA results, and 1 false-negative PCR result (1 cat lost to follow-up).
  
  
  CONCLUSIONS
  While there was good agreement between the POC ELISA and PCR tests, the discordant results highlight the importance of cautious interpretation of test results and the necessity of confirmatory testing.
authors.affiliation: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN.
authors.forename: J
authors.initials: J
authors.lastname: Nichols
authors.affiliation: Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN.
authors.forename: H Y
authors.initials: HY
authors.lastname: Weng
authors.affiliation: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN.
authors.forename: A
authors.initials: A
authors.lastname: Litster
authors.affiliation: IDEXX Laboratories, West Sacramento, CA.
authors.forename: C
authors.initials: C
authors.lastname: Leutenegger
authors.affiliation: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN.
authors.forename: L
authors.initials: L
authors.lastname: Guptill
mesh_terms: D000818:Animals; D002371:Cat Diseases / Q000821:virology*; D002415:Cats; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D016089:Immunodeficiency Virus, Feline / Q000302:isolation & purification*; D008137:Longitudinal Studies; D008297:Male; D011446:Prospective Studies; D011933:Reagent Kits, Diagnostic / Q000662:veterinary; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D012192:Retroviridae Infections / Q000662:veterinary* / Q000821:virology; D012680:Sensitivity and Specificity
chemical_list: D011933:Reagent Kits, Diagnostic
keywords: Diagnosis; Infectious disease; Retrovirus