What are the symptoms of Rocky Mountain spotted fever?

From the Guidelines

Rocky Mountain spotted fever symptoms typically include fever, headache, and a characteristic rash that usually appears 2-4 days after fever onset, with early symptoms often resembling flu, including fever, chills, severe headache, muscle aches, nausea, vomiting, and loss of appetite. The rash begins as small, flat, pink, non-itchy spots on the wrists, forearms, and ankles, then spreads to the trunk and sometimes palms and soles 1. Some patients may also experience abdominal pain, joint pain, and diarrhea. It's essential to note that the classic triad of fever, rash, and reported tick bite is rarely present when patients with RMSF first seek care, and absence of rash should not preclude consideration of RMSF 1.

Key Symptoms

• Fever
• Headache
• Rash (usually appears 2-4 days after fever onset)
• Chills
• Severe headache
• Muscle aches
• Nausea
• Vomiting
• Loss of appetite
• Abdominal pain
• Joint pain
• Diarrhea

Importance of Early Treatment

Without treatment, the disease can progress to cause serious complications, including damage to blood vessels, internal bleeding, inflammation of the heart, lungs, or brain, kidney failure, and even death 1. Early treatment with doxycycline is crucial, even before rash development, as delayed treatment significantly increases complication and mortality risk 1. If you develop these symptoms after potential tick exposure, seek medical attention immediately, as prompt treatment is essential to prevent RMSF progression and resultant morbidity and mortality 1.

From the Research

Symptoms of Rocky Mountain Spotted Fever

The symptoms of Rocky Mountain spotted fever (RMSF) can be subtle and overlap with other clinical conditions, making diagnosis challenging 2. The disease is characterized by:

• Fever
• Headache
• Photophobia
• Malaise
• Myalgias
• A petechial rash that begins on the wrists and ankles and spreads to the trunk 2, 3, 4
• Gastrointestinal complaints 3
• Abdominal pain 4
• Nausea and vomiting 5
• Anorexia 5
• Joint pain 6
• Dry cough 6

Clinical Presentation

The classic triad of fever, headache, and rash is not definitive, and the rash may not occur in up to 15% of patients 2. The disease can progress to more severe symptoms, including:

• Generalized vasculitis
• Periorbital edema
• Nonpitting edema of the face and extremities 3
• Central nervous system involvement 3
• Cardiovascular compromise
• Coma
• Death 4

Laboratory Findings

Laboratory evaluation may demonstrate:

• Hyponatremia
• Anemia
• Thrombocytopenia
• Abnormal liver enzymes
• Elevated coagulation tests 2
• Antibody testing can be helpful, but results are not typically available to the emergency clinician 2