Clinical, Laboratory Diagnosis and Treatment of Ehrlichial Infections in Dogs: A Review

Abstract

Canine ehrlichiosis, a tick borne disease, is caused by an intracellular bacteria belonging to the genus Ehrlichia. It is one of the most important diseases in dogs and other canids in tropical and subtropical regions. The disease is transmitted transstadially, mainly, by the nymph and adult stages of the brown dog tick, Rhipicephalus sanguineus. Clinically the disease can take the acute or chronic form with a wide range of clinical presentations that include fever, depression, lethargy, dyspnea, anorexia, weight loss, lymphadenopathy, hemorrhage, epistaxis, increased hair loss, vomiting, blindness, edema, ataxia and polyarthritis. Superinfection with other organisms can complicate the clinical picture making clinical diagnosis difficult. Several diagnostic tests, notably identification of morulae in blood smears, in-vitro cell culture technique, indirect fluorescent test (IFA), enzyme linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR ) have been developed for the confirmation of the disease. The abundance of Rhipicephalus sanguineus in most areas in Kenya, due to favorable weather, increases the risk of the disease in dogs kept in such areas despite the control measures. Whenever the small animal clinicians are presented with cases of dogs having non-specific clinical signs, especially in Nairobi and other areas having similar climatic conditions, it would be prudent to consider the possibility of canine ehrlichiosis. At the moment the treatment protocol entails use of doxycycline or imidocarb dipropionate.

The Kenya Veterinarian Vol. 29 2005: pp. 71-75