The Evaluation and Management of Rocky Mountain Spotted Fever in the Emergency Department: a Review of the Literature

Background: Rocky Mountain spotted fever (RMSF) is potentially deadly and can present subtly with signs and symptoms overlapping with other clinical conditions. Delayed diagnosis can be fatal. Objective: This review provides an evidence-based summary of the current data for the evaluation and management of RMSF in the emergency department. Discussion: RMSF occurs through transmission of Rickettsia rickettsii by an infected tick. Exposure in the United States occurs most commonly from April to September, and high-risk locations include wooded, shrubby, or grassy areas. Approximately half of patients with infection do not recall tick exposure. Symptoms can include fever, headache, photophobia, malaise, myalgias, and a petechial rash that begins on the wrists and ankles and spreads to the trunk. Rash may not occur in ≤15% of patients, and the classic triad of fever, headache, and rash is also not definitive. Laboratory evaluation may demonstrate hyponatremia, anemia, thrombocytopenia, abnormal liver enzymes, and elevated coagulation tests. Antibody testing can be helpful, but these results are not typically available to the emergency clinician. Doxycycline is the treatment of choice in adults, children, and pregnant patients. Patients should be advised about prevention strategies and effective techniques for removing ticks. Conclusions: RMSF is a potentially deadly disease that requires prompt recognition and management. Focused history, physical examination, and testing are important in the diagnosis of this disease. Understanding the clinical features, diagnostic tools, and proper treatment can assist emergency clinicians in the management of RMSF.