Evaluation of a serum-based PCR assay for the diagnosis of canine monocytic ehrlichiosis.
The aim of this study was to estimate the relative diagnostic sensitivity and specificity of a polymerase chain reaction (PCR) assay in the serum of dogs with naturally occurring non-myelosuppressive canine monocytic ehrlichiosis (CME), and to investigate the association between PCR positivity and immunofluorescence antibody (IFA) titres for Ehrlichia canis. Serum samples obtained from 38 dogs with non-myelosuppressive CME and 12 healthy dogs were analyzed retrospectively. Each serum sample was analyzed in triplicate using an E. canis-specific nested PCR assay targeting a 389bp sequence of the 16S rRNA gene. E. canis DNA was amplified in 24 of 38 (63.1%) affected dogs; all samples from healthy dogs were negative. A high level of agreement was found among the PCR replicates (P<0.0001). Median IFA titre of the 24 PCR-positive dogs was significantly lower than that of the PCR-negative infected dogs (P=0.0029), indicating that E. canis DNA may circulate prior to the development of a high antibody titre. Serum-based PCR analysis is suggested for the early diagnosis of CME when whole blood samples are not available.
Aristotle University of Thessaloniki, Greece. mmylonak@vet.auth.gr
Mathios E
ME
Mylonakis
Victoria I
VI
Siarkou
Leonidas
L
Leontides
Eleftheria
E
Bourtzi-Hatzopoulou
Vassilios I
VI
Kontos
Alexander F
AF
Koutinas
D000818:Animals; D004283:Dog Diseases / Q000097:blood / Q000175:diagnosis*; D004285:Dogs; D016873:Ehrlichiosis / Q000097:blood / Q000175:diagnosis / Q000662:veterinary*; D016133:Polymerase Chain Reaction / Q000662:veterinary*; D012189:Retrospective Studies; D012698:Serologic Tests / Q000662:veterinary*