Complications

Rocky Mountain spotted fever damages the lining of your smallest blood vessels, causing the vessels to leak or form clots. This may cause:

• Inflammation of the brain (encephalitis). In addition to severe headaches, Rocky Mountain spotted fever can cause inflammation of the brain, which can cause confusion, seizures and delirium.
• Inflammation of the heart or lungs. Rocky Mountain spotted fever can cause inflammation in areas of the heart and lungs. This can lead to heart failure or lung failure in severe cases.
• Kidney failure. Your kidneys filter waste from your blood, and the blood vessels within the kidneys are very small and fragile. Damage to these vessels can eventually result in kidney failure.
• Serious infection, possibly amputation. Some of your smallest blood vessels are in your fingers and toes. If these vessels don't work properly, the tissue at your farthest extremities may develop gangrene and die. Amputation would then be necessary.
• Death. Untreated, Rocky Mountain spotted fever has, historically, had a death rate as high as 80 percent.