Rocky Mountain spotted fever following cardiac transplantation.

ROCKY MOUNTAIN SPOTTED FEVER was first recognized in the early 1 900s in the Snake River Valley of Idaho and the Bitterroot Valley of western Montana.t In 1909, Howard Taylor Ricketts established the ixodid tick as the vector for the disease.2 Following the tick bite, the incubation period averages seven days (4 to 10 days), and the disease varies in severity and course. Typically a patient's temperature remains elevated to 39°C to 400C (102OF to 1040F). A characteristic rash, a relatively late manifestation, may appear on the wrists and ankles and extend throughout the body, including the palms and soles. Initially there are erythematous macules that blanch with pressure, but after several days the rash becomes maculopapular and petechial. The rash begins to clear as the fever resolves, but lesions may remain visible for as long as several weeks. Widespread vascular damage may occur involving the skin, lungs, heart (myocarditis), brain, pancreas, liver, skeletal muscle, or kidneys. The endothelial cell injury leads to increased vascular permeability, edema, hypovolemia, and hypotension.3