Rocky Mountain spotted fever is a relatively rare bacterial disease spread through bites from infected ticks. The infection itself is caused by the Rickettsia rickettsii parasite.
Rocky Mountain spotted fever was first identified in the Rocky Mountains of the United States, and it is frequently found throughout the southeastern portion of the country. Cases have also been identified in Canada, Mexico, and Central and South America.
Symptoms normally appear within seven days of infection, and some patients may not show symptoms for up to two weeks. Some of the most common symptoms of Rocky Mountain spotted fever are a high fever, chills, muscle aches, and confusion.
Patients may also have severe headache, nausea and vomiting. Sometimes, patients may develop a specific type of rash within three to five days after infection. This rash does not itch, and it generally begins on the wrists and ankles, though it can spread up to the torso and along the arms and legs.
Some patients with Rocky Mountain spotted fever will never develop a rash, which can complicate diagnosis. In fact, since the symptoms mimic those of other illnesses, Rocky Mountain spotted fever may sometimes be misdiagnosed as influenza or other less serious conditions.
Rocky Mountain spotted fever can be confirmed through a blood test, and antibiotics are normally started immediately if clinicians suspect a patient has this condition.
Causes and Complications of Rocky Mountain Spotted Fever
The major causes and complications of Rocky Mountain spotted fever are described below.
1. Contact with Infected Ticks
Rocky Mountain fever is transmitted to humans through contact with infected ticks. Infections are most common when ticks are active during the spring and summer.
In the United States, patients who live in the southeastern area of the nation are at an elevated risk of this disease.
Generally, ticks are likely to be encountered on hikes through grassy or wooded areas, and patients are advised to wear long sleeved shirts, long pants, and hats when hiking in these areas. Ideally, clothing should be sprayed with an insect repellent.
Patients should also examine their skin after a hike to check for the presence of any ticks, and these should be pulled out with tweezers and flushed down the toilet.
Occasionally, patients have caught Rocky Mountain spotted fever through contact with dogs that carry ticks. Dog owners should be especially careful to use tick prevention medicines for their pets, and any ticks discovered on a dog should be removed immediately.
Encephalitis is a serious inflammation of the brain, and it is one of the many complications of Rocky Mountain spotted fever. Symptoms of encephalitis begin with a headache, muscle aches, fever, and fatigue.
As the condition worsens, patients may experience seizures, hallucinations, confusion, speech and hearing difficulties, and loss of sensation in certain areas of the body. Eventually, encephalitis may result in loss of consciousness.
MRI scans and CT scans can be used to diagnose encephalitis. When caused by Rocky Mountain spotted fever, treatment for encephalitis is provided at the same time as treatment for the tickborne infection.
Bed rest, intravenous fluids, anti-inflammatory medication, anticonvulsants, and breathing assistance (ventilation) may all be used.
3. Kidney Failure
Kidney failure often occurs when treatment for Rocky Mountain fever is delayed. Healthy kidneys filter waste products from the blood, and this filtration process becomes ineffective or completely stops once kidney failure has occurred.
For patients with Rocky Mountain spotted fever, the kidneys often stop functioning very suddenly. This is known as acute kidney (renal) failure. Symptoms of acute kidney failure include pain in the abdomen or back, diarrhea, fever, nosebleeds, rashes, and vomiting.
To treat this condition, patients must begin dialysis immediately. Dialysis takes over the normal function of the kidneys, and the blood is filtered through a machine.
Patients normally have dialysis at specialized centers, though some patients may be able to have this procedure at their homes.
Normally, dialysis must be given at least three to seven times a week, and the process can take around four hours each time. Some patients with kidney failure may be candidates for a kidney transplant.
4. Heart or Lung Inflammation
Heart or lung inflammation may develop as Rocky Mountain spotted fever progresses. Inflammation that occurs in or around the heart is known as myocarditis.
Patients with myocarditis may experience shortness of breath, chest pain, heart rhythm abnormalities, fatigue, and swelling in the feet or lower limbs. Echocardiograms and MRI scans can help doctors assess the severity of myocarditis.
Generally, myocarditis will resolve on its own if Rocky Mountain fever is treated successfully. In some cases, myocarditis can progress to heart failure, and patients may need a heart transplant.
There are many types of lung inflammation, and patients with this complication often have a cough, shortness of breath, and unintentional weight loss. To diagnose lung inflammation, doctors will perform blood tests, CT scans, chest x-rays, and pulmonary function tests.
Patients who experience severe breathing difficulties may need to use supplemental oxygen therapy at home, and corticosteroids may be beneficial for some patients.
5. Severe Infection and Amputation
Rocky Mountain spotted fever may lead to severe infection and amputation in some instances. As the infection spreads, it will affect the blood vessels in fingers and toes and restrict blood flow to these areas.
With blood flow restricted, the tissues in the extremities could develop gangrene. Considered a medical emergency, gangrene caused by Rocky Mountain fever typically results in tissue swelling.
Blisters and pus-filled discharge are often present, and the affected tissue dies. This type of gangrene can spread quickly throughout the body, and finger, toe, and limb amputations may sometimes be necessary as doctors attempt to stop the spread of this infection.
Patients who notice any changes in skin color, numb sensations, blisters, or swelling should inform their healthcare team immediately.