title: Comparison of polymerase chain reaction assays with bacteriologic culture, immunofluorescence, and nucleic acid hybridization for detection of Leptospira borgpetersenii serovar hardjo in urine of cattle.
abstract: OBJECTIVE
  To compare sensitivity and specificity of various polymerase chain reaction (PCR) assays for detection of Leptospira borgpetersenii serovar hardjo in bovine urine and to compare results of the optimal PCR assay with results of immunofluorescence, nucleic acid hybridization, and bacteriologic culture.
  
  
  METHODS
  6 heifers.
  
  
  METHODS
  Heifers were exposed to serovar hardjo type hardjo-bovis by conjunctival instillation of 10(6) leptospires on 3 successive days. Urine samples were collected before and after infection. Sensitivity and specificity of 5 PCR assays were compared, to determine the optimal assay for use with bovine urine samples. The optimal PCR assay was then compared with results of bacteriologic culture, nucleic acid hybridization, and immunofluorescence.
  
  
  RESULTS
  A PCR assay with the best combination of specificity (100%) and sensitivity (91%) was selected for comparison with the other diagnostic tests. Sensitivity for nucleic acid hybridization was 55%, whereas sensitivity for bacteriologic culture and immunofluorescence was 89 to 93%.
  
  
  CONCLUSIONS
  Bacteriologic culture, PCR, and immunofluorescence were sensitive for detection of L borgpetersenii serovar hardjo type hardjo-bovis in urine specimens of cattle, but a single technique was not the most sensitive for each animal tested. Therefore, the use of 2 techniques in combination is warranted for maximal sensitivity for diagnosis.
authors.affiliation: Department of Bacteriology, Institute of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Wagenaar
authors.forename: R L
authors.initials: RL
authors.lastname: Zuerner
authors.forename: D
authors.initials: D
authors.lastname: Alt
authors.forename: C A
authors.initials: CA
authors.lastname: Bolin
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000737:chemistry; D001431:Bacteriological Techniques; D015139:Blotting, Southern / Q000662:veterinary; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis* / Q000382:microbiology; D017931:DNA Primers / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification; D004587:Electrophoresis, Agar Gel / Q000662:veterinary; D005260:Female; D007919:Leptospira / Q000235:genetics / Q000302:isolation & purification*; D007922:Leptospirosis / Q000175:diagnosis / Q000662:veterinary*; D008856:Microscopy, Fluorescence / Q000662:veterinary; D009693:Nucleic Acid Hybridization; D016133:Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary*; D012680:Sensitivity and Specificity; D014556:Urine / Q000382:microbiology
chemical_list: D000907:Antibodies, Bacterial; D017931:DNA Primers; D004269:DNA, Bacterial