| • | organism – Rickettsia akari |
| • | vector – mite of the house mouse (liponyssoides sanguines) |
clinical:
| • | high fever and distinctive rash (unusual among rickettsial diseases in that its eruption is vesicular) |
| • | initial lesion = large black eschar at site of original mite bite |
| • | vesicopustular eruption that is acneiform in appearance (lesions are sparse) |
| • | vesicle on top of papule (histology: lymphocytic vasculitis and thrombosis) |
diagnosis:
| • | but chicken pox is in children, and with no "initial lesion" |
| • | and in chicken pox rash appears with fever and vesicle is on a macule (vs. fever before rash, vesicle on top of papule in RP) |
| • | Weil-Felix (-) (vs. RMSF) |
| • | definitive diagnosis = rising antibody titers |
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