Rickettsia conorii
From IDWiki
- A tickborne rickettsial species that causes boutonneuse fever, the most severe form of rickettsial spotted fever next to Rocky Mountain spotted fever
- Also known as Marseilles fever, Mediterranean spotted fever, Kenya tick typhus, Israeli tick typhus, Astrakhan spotted fever, and Indian tick typhus
Background
Microbiology
- Species of Rickettsia within the spotted fever group
Life Cycle
- Maintained transovarially within the tick species
Epidemiology
- Transmitted by Rhipicephalus sanguineus ticks
- Founds in India, Pakistan, Israel, Russia, Georgia, Bulgaria, Turkey, Ukraine, Ethiopia, Kenya, South Africa, Morocco, and southern Europe
- More cases occur during the warm months (July through September in the Mediterranean)
Clinical Manifestations
- Incubation period of 7 days
- Initial symptoms include fever, myalgias, and headache
- Often has an eschar at the site of tick bit inoculation ("tache noir"), but not always
- Petechial rash, GI symptoms, obtundation, tachypnea, hepatomegaly, leukocytosis, coagulopathy, AKI, bilirubin elevation, AST elevation, and CK elevation
- Procoagulant, and 10% develop DVT
- Can present as acute pancreatitis
- Can be quite severe with higher mortality than others in the spotted fever group
Management
- First-line: doxycycline 100 mg po bid for 7 days (at least 5-7 days and resolution of symptoms for 3 days)
- May be able to shorten to a single day of two doses of 200 mg each in one small study
- Could use minocycline
- Ciprofloxacin is associated with a more severe course and should be avoided
- Azithromycin or clarithromycin may be considered in pregnant women or children
