First reported case of Ehrlichia ewingii involving human bone marrow

Area of Science:

• * Infectious Diseases
• * Hematology
• * Microbiology

Background:

• * Ehrlichia ewingii is a tick-borne bacterium known to cause illness in humans and animals.
• * Human infections typically manifest with febrile illness and cytopenias, but bone marrow involvement is rarely documented.

Observation:

• * A 65-year-old female presented with fever and pancytopenia following multiple tick bites.
• * Peripheral blood smear and bone marrow biopsy revealed intracytoplasmic morulae, characteristic of Ehrlichia infection.

Findings:

• * Polymerase chain reaction (PCR) confirmed the presence of Ehrlichia ewingii DNA in both peripheral blood and bone marrow specimens.
• * This case represents the first documented instance of Ehrlichia ewingii infecting human bone marrow.

Implications:

• * Highlights the potential for Ehrlichia ewingii to cause significant hematologic abnormalities, including bone marrow infection.
• * Emphasizes the importance of considering ehrlichiosis in the differential diagnosis of febrile illnesses with pancytopenia, especially in endemic areas.
• * Suggests bone marrow examination may be valuable in diagnosing severe or atypical cases of ehrlichiosis.