Orientia tsutsugamushi
From IDWiki
- Chigger-borne rickettsial infection caused by the intracellular Gram-negative bacterium Orientia tsutsugamushi that causes scrub typhus
Background
Life Cycle
- The entire life cycle is maintained within Leptotrombidium mites by vertical/transovarial transmission
- Leptotrombidium larvae (called chiggers) normally feed on rodents, and occasionally humans, who are dead-end hosts
Epidemiology
- Most common in rural Asia and western Australia, as well as other parts of eastern Asia, including Russia and India
Clinical Presentation
- Fever, headache, myalgia, lymphadenopathy, and an eschar
- Lymphadenopathy sometimes grouped near the eschar
- Should almost always be able to find the eschar if you look hard enough
- Transient pale macular rash
- May have cough
- May have mental status changes and hepatosplenomegaly
- In severe cases, may progress to multiorgan failure and hemorrhage
- After treatment, may relapse
- Infection also decreases HIV viral load and can lead to immune reconstitution
Diagnosis
- Four-fold rise in immunofluorescence serology
- PCR on eschar, blood, or lymph node biopsy
Management
- Doxycycline 100 mg po bid for 7 days
