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Co-infections: Rickettsia Diseases

Rickettsia Diseases

  • Some Diseases Caused by the Rickettsia Bacteria

  • Ehrlichiosis  (HME, human monocytic ehrlichiosis)

  • Anaplasmosis (HGA, human granulocytic anaplasmosis, formerly called HGE)

  • Rocky Mountain Spotted Fever (RMSF)

  • Spotted Fever Group Rickettsias (SFGR)
    May cause milder illness than Rocky Mountain spotted fever


Ehrlichiosis, Anaplasmosis, and Rocky Mountain Spotted Fever share Similar Symptoms

  • Fever

  • Chills

  • Severe headache

  • Muscle aches or pain

  • Confusion

  • Meningitis

  • Abdominal pain

  • Nausea

  • Vomiting (sometimes)

  • Diarrhea (sometimes)

  • Rash

Rickettsia Disease Rash
  • Flat red and/or bumpy rash.

  • Rash doesn’t appear for several days.

  • Many people with Rocky Mountain spotted fever don’t get a rash.

  • The rash is rare in anaplasmosis and ehrlichiosis.

  • The RMSF rash typically begins at the wrists and ankles and moves up the limbs.

  • May also occur on the palms of the hands and soles of the feet.

  • Spotted fever group rickettsias may cause a milder illness than these other diseases.

Treatment of Rickettsial Diseases
  •  Treatment is most successful if begun promptly (before the 5th day of illness).

  • Don’t wait for test results.

  • Tests are usually negative early in the illness.

  • Begin treatment as soon as a rickettsial disease is suspected.

  • These diseases can be fatal if treatment is delayed.

Diagnosis Issues
  • Rickettsial diseases can be confused with the flu or viral meningitis.

  • They may not get diagnosed until the rash appears.

  • These diseases cause low platelet count, low white blood cell count, and elevated liver enzymes. A CBC panel and liver enzyme test should be ordered.

  • Antibody tests can be ordered, but treatment must not wait for the antibody test results.

  • Antibody tests for anaplasma are likely to be negative during the first week or two of infection.

  • People can get Lyme disease along with these diseases.

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