The great imitator: Rocky Mountain spotted fever occurring after hospitalization for unrelated illnesses.

We describe two patients who had Rocky Mountain spotted fever after they were admitted to the hospital for emergency and elective surgical procedures. We initially thought one patient had a hospital-acquired infection; the correct diagnosis was deduced from epidemiologic clues elicited by consultants. These two cases were also unusual in that one patient had a recurrent rash after an abbreviated course of low-dose doxycycline therapy and the other patient had transient and self-limiting postinfectious polyneuropathy. These cases illustrate that community-acquired infection with Rickettsia rickettsii can occur simultaneously with other disease processes and sometimes mimic a nosocomial infection.