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Ehrlichiosis and anaplasmosis

Last reviewed: 30 Sep 2024
Last updated: 06 Jun 2023

Summary

Definition

History and exam

Key diagnostic factors

  • history of tick bite/exposure
  • history of immunosuppression
  • fever
  • headache
  • malaise
  • myalgia
  • arthralgia
  • nausea
  • small erythematous lesion with or without necrotic center
  • nonspecific rash
Full details

Other diagnostic factors

  • vomiting
  • diarrhea
  • abdominal pain
  • cough
  • dyspnea
  • stiff neck
  • confusion
  • photophobia
  • stupor
  • coma
  • seizures
  • lymphadenopathy
  • jaundice
  • hepatomegaly
  • splenomegaly
  • secondary infections
Full details

Risk factors

  • tick bite/exposure
  • immunosuppression
  • age over 60 years
  • male sex
Full details

Diagnostic tests

1st tests to order

  • CBC
  • LFTs
  • peripheral blood smear
Full details

Tests to consider

  • immunofluorescence antibody assay
  • polymerase chain reaction
Full details

Emerging tests

  • Western immunoblotting
  • culture
  • immunohistochemistry

Treatment algorithm

INITIAL

adults

children

Contributors

Authors

Juan P. Olano, MD

Professor

Department of Pathology

University of Texas Medical Branch

Galveston

TX

Disclosures

JPO is the author of a number of references cited in this topic.

Peer reviewers

Hariharan Regunath, MD, FACP, FIDSA

Adjunct Assistant Professor of Clinical Medicine

Department of Medicine - Divisions of Infectious Diseases and Pulmonary & Critical Care Medicine

University of Missouri

Columbia

MO

Disclosures

HR declares that he has no competing interests.

Richard Reithinger, MD, PhD

Professor

London School of Hygiene and Tropical Medicine

London

UK

Disclosures

RR declares that he has no competing interests.

  • Ehrlichiosis and anaplasmosis images
  • Differentials

    • Pneumonia, bacterial or viral
    • Gastroenteritides, bacterial or viral
    • Cholecystitis
    More Differentials
  • Guidelines

    • CDC yellow book health information for international travel: rickettsial diseases
    • Tickborne diseases of the United States: a reference manual for health care providers
    More Guidelines
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