EHRLICHIOSIS / ANAPLASMOSIS

Question 1

Signs and symptoms

Answer 1

headache, myalgia (i.e., muscle pain), malaise (i.e., general discomfort or uneasiness), anemia, leucopenia (i.e., low white blood cell count), thrombocytopenia (i.e., decrease in the number of blood platelets often associated with hemorrhagic conditions), or elevated hepatic transaminases (i.e., possible indicator of liver damage). Nausea, vomiting,
or rash may be present in some cases. Intracytoplasmic bacterial aggregates (morulae) may be visible in the leukocytes (i.e., white blood cells) of some patients.

Question 2

What transmits Ehrlichiosis?

Answer 2

Ticks

Question 3

Serological evidence of a fourfold change in immunoglobulin G (IgG)-specific antibody titer to E. chaffeensis antigen by indirect immunofluorescence assay (IFA) between paired serum samples (one taken in first week of illness and a second 2-4 weeks later);
• Detection of E. chaffeensis DNA in a clinical specimen via amplification of a specific target by polymerase chain reaction (PCR) assay;
• Demonstration of ehrlichial antigen in a biopsy or autopsy sample by immunohistochemical methods; or
• Isolation of E. chaffeensis from a clinical specimen in cell culture.

Answer 3

Confirmatory for Ehrlichia chaffeensis infection

Question 4

Because the organism has never been cultured, antigens are not available. Thus, Ehrlichia ewingii infections may only be diagnosed by molecular detection methods: E. ewingii DNA detected in a clinical specimen via amplification of a specific target by polymerase chain reaction (PCR) assay.

Answer 4

Confirmatory for Ehrlichia ewingii infection