By: Samantha Schaub & Kimberlee Sofka Ehrlichiosis

Ehrlichia attacks and kills WBC’s The organisms that cause ehrlichiosis are small, gram- negative, coccobacilli (bacterium) There are three intracytoplasmic forms: initial body elementary body morulae Ehrlichia attacks and kills WBC’s The organisms that cause ehrlichiosis are small, gram- negative, coccobacilli (bacterium) There are three intracytoplasmic forms: initial body elementary body morulae gram-negative coccobacilli morulae in a WBC Etiology:

ZOONOSIS The zoonotic species are: Ehrlichia chaffeensis (Tick: Amblyomma americanum) Ehrlichia ewingii: (Tick: Amblyomma americanum) Ehrichia muris like (EML)

Ehrlichia canis was first recognized in the U.S. in The disease gained prominence because of the large losses of military dogs stationed in Vietnam. Ehrlichiosis is primarily seen in tropical & subtropical environments. History:

Signalment: Ehrlichia can infect many species, regardless of age or sex. German Shepherd Dogs (Doberman pinschers) are predisposed to getting chronic cases of Ehrlichia canis.

Transmission: Similar to ehrlichia Various species of ticks. Blood transfusions from an infected animal. Other biting insects have been suggested as a possible means of transmission. Rhipicephalus Sanguineus the brown dog tick is the most common vector for Ehrlichia canis.

Clinical Signs Signs have been divided into 3 stages. Acute: fever, swollen lymphnodes, respiratory distress, weight loss, and bleeding disorders lasting 2-4 Weeks. Subclinical: represents the stage of infection in which the organism is present, but not causing any signs of disease. Dog may eliminate the organism, or progress to the next stage. May last for years Chronic: long lasting infection. This stage occurs when the immune system is not functioning properly. Symptoms include anemia, thrombocytopenia, bleeding episodes, lameness, and neurological problems. Bone marrow suppression.

Clinical Signs: Recurring fever Photophobia Vomiting Splenomegaly Depression/anorexia Weight loss Dyspnea Edema of the limbs Develop around 1-2 weeks after being bitten by an infected tick.

Diagnostic Tests and Results: Hemotology & Serology tests Pancytopenia Aplastic anemia Leukopenia Thrombocytopenia Increase serum proteins Finding organisms/morulae within blood smears Immunofluorescent antibody test an example of an IFA test for ehrlichia antibodies

Diagnostic Tests & Expected Results Confirmation of Ehrlichiosis requires serologic, mollecular, or culture-based methods.

Treatment: Tetracycline- TID for approx. 2 weeks in acute cases or 1-2 mo. in chronic cases. Given PO. Doxycycline- SID for days. Can be given PO or IV. If the dog is unresponsive Chloramphenicol is used as a second choice.

Prognosis: Ehrlichia is rarely fatal. In acute cases, patients improve within hours. In chronic cases, hematologic abnormalities may persist for up to 6 months. Dogs with weak immune systems and those progressed to terminal stages of infection have a guarded prognosis.

Pathologic lesions of disease: Lesions are generally nonspecific. Consistent with hemorrhage of the: Mucosae layer of GI Urogenital & kidney tracts Splenomegaly is common. Hemmorhagic enlargements of most lymph nodes and edema of the limbs. top right: hemorrhage of the mucosae. bottom right: enlarged lymph node. The tissues evaluated for the presence of E. Canis include lymph nodes, spleen, liver, bone marrow, and blood.

Prevention An owner can use flee prevention such as Products which repel and kill ticks preferably those containing permethrins are. Tick collars containing the active ingredient amitraz (Preventic collars) are also used

Client Education: Reinfection is a possibility. Long-term tetracycline prophylaxis may be required. Tick control is key in prevention! Using seronegative screened blood donors.

Case Study:

References: Common Diseases of Companion Animals. By: Alleice Summers. Textbook. The Merck Veterinary Manual. Online.. hrlichiosis Veterinary Pathology. By: Thomas Jones, Ronald Hunt, & Norval King. Online..ology&hl=en&ei=0- 5yTau3BYH98AbS4rnFCA&sa=X&oi=book_result&ct=result&resnum=1&ved=0CD IQ6AEwAA#v=onepage&q&f=false>. CDC- Ehrlichiosis. Online. < CDC- Ehrlichiosis. Online.. IDEXX Labratories (case study). Online..

REFERENCES d=430 d=430 tm/bc/57302.htm&word=ehrlichia tm/bc/57302.htm&word=ehrlichia Common Diseases of Companion Animals (book)