Clinical relevance of annual screening using a commercial enzyme-linked immunosorbent assay (SNAP 3Dx) for canine ehrlichiosis

• Published in: The Journal of the American Animal Hospital Association Vol. 45; no. 3; p. 118
• Main Authors: Hegarty, Barbara C, de Paiva Diniz, Pedro Paulo Vissotto, Bradley, Julie M, Lorentzen, Leif, Breitschwerdt, Edward
• Format: Journal Article
• Language: English
• Published: United States 01-05-2009
• Subjects: Animals; Diagnosis, Differential; Diagnostic Tests, Routine - methods; Diagnostic Tests, Routine - standards; Diagnostic Tests, Routine - veterinary; Dog Diseases - blood; Dog Diseases - diagnosis; Dogs; Ehrlichia - genetics; Ehrlichia - immunology; Ehrlichia - isolation & purification; Ehrlichiosis - blood; Ehrlichiosis - diagnosis; Ehrlichiosis - veterinary; Enzyme-Linked Immunosorbent Assay - standards; Enzyme-Linked Immunosorbent Assay - veterinary; Fluorescent Antibody Technique - standards; Fluorescent Antibody Technique - veterinary; Polymerase Chain Reaction - standards; Polymerase Chain Reaction - veterinary; Thrombocytopenia - blood; United States; United States
• ISSN: 1547-3317
• DOI: 10.5326/0450118

Eighty-six dogs were selected based upon Ehrlichia (E.) canis SNAP 3Dx positive results to determine clinical relevance of annual E. canis screening. Immunofluorescence assay showed 72 (84%) of 86 dogs were seroreactive for E. canis. Polymerase chain reaction (PCR) revealed that 12 (14%) of 86 dogs had Ehrlichia deoxyribonucleic acid; seven had E. canis, four had E. ewingii, and one was coinfected with E. chaffeensis and E. ewingii. Thrombocytopenia (<164,000 platelets/microL) was found in 28 (39%) of 72 dogs. In this study, thrombocytopenia was frequently detected in healthy Ehrlichia SNAP 3Dx-positive dogs, whereas active infection was infrequently confirmed by PCR. Therefore, treatment based upon screening results alone is not recommended.