Rickettsial pox

Last Updated: 2023-07-07

Author(s): Anzengruber F., Navarini A.

ICD11: 1C32

Shankmann 1946.

Rickettsiosis caused by Rickettsia acarii.

  • In New York in particular, several smaller endemics appeared.
  • 800 cases had been registered by 2010.

  • Pathogen
    • Rickettsia acarii.
  • Transmission occurs through mouse and rat mites. R. acarii belongs to the "spotted fever group".

  • Unspecific early stage (cephalgia, exhaustion).
  • In the course: Fever, somnolence.
  • 3rd-6th days after onset of fever Appearance of roseolae with partly punctate haemorrhages on the trunk, which spread centrifugally. Palmoplantar involvement.
  • Muscle twitching, tenderness of peripheral nerves, motor restlessness.
  • Hypotonia.
  • Bronchitis, conjunctivitis, splenomegaly.
  • Mostly lice can be detected (pediculosis corporis).
  • Facies typhosa: Livid-reddish face.
  • Apartially later ulcerating papulovesicles are seen in the area of the inoculation site.

  • Anamnesis.
  • Clinical.
  • Lice infestation.
  • BB (leukopenia, eosinophilia, thrombocytopenia, ESR ↑), liver and kidney values (transaminases↑), electrolytes.
  • From 2. Week of illness Weil-Felix reaction (agglutination test).
  • From the 3rd week of illness complement fixation reaction.
  • From the 3rd week of illness indirect immunofluorescence test.

  • Favourable.
  • Temperatures are regressive under antibiotic therapy after 1-2 days.

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