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Ehrlichioses in humans: epidemiology, clinical presentation, diagnosis, and treatment

J Stephen Dumler1, John E Madigan, Nicola Pusterla

  • 1Division of Medical Microbiology, Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA. sdumler@jhmi.edu

Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
|July 14, 2007
PubMed

Insights

Human ehrlichioses are emerging tickborne bacterial infections. Early diagnosis and doxycycline treatment are crucial for managing these increasingly prevalent diseases, which present with fever and characteristic lab abnormalities.

Area of Science:

  • Infectious Diseases
  • Microbiology
  • Tick-borne Illnesses

Background:

  • Human ehrlichioses are emerging tick-borne infections caused by bacteria in the Anaplasmataceae family.
  • Key pathogens include Ehrlichia chaffeensis (HME), Anaplasma phagocytophilum (HGA), and Ehrlichia ewingii.
  • These infections are increasing in prevalence and incidence.

Purpose of the Study:

  • To review the epidemiology, clinical features, and laboratory diagnostics of human ehrlichioses.
  • To highlight the increasing incidence and geographic spread of these tick-borne diseases.
  • To emphasize the importance of prompt diagnosis and treatment.

Main Methods:

  • Literature review of human ehrlichioses.
  • Analysis of clinical presentations and laboratory findings.
  • Discussion of diagnostic methods and treatment strategies.

Main Results:

  • Human ehrlichioses present as undifferentiated fever with common laboratory findings of thrombocytopenia, leukopenia, and elevated transaminases.
  • Human monocytic ehrlichiosis (HME) is associated with greater severity and higher fatality rates.
  • Human granulocytic anaplasmosis (HGA) has a higher prevalence of opportunistic infections.

Conclusions:

  • Prompt recognition of human ehrlichioses based on clinical and historical grounds is essential.
  • Doxycycline is the recommended treatment and should be initiated early.
  • Laboratory confirmation through blood smear, PCR, culture, and serology aids in etiologic diagnosis.

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