Family Nurse Practitioner Exam

A patient presents with fever and a rash on the palms and ankles spreading to the trunk. What is the likely diagnosis?

1. Kawasaki's disease

2. Meningococcemia

3. Rocky Mountain spotted fever

4. Measles

The correct answer is: Rocky Mountain spotted fever

The presentation of fever and a rash on the palms and ankles that spreads to the trunk is highly indicative of Rocky Mountain spotted fever (RMSF). This condition is caused by the tick-borne bacterium Rickettsia rickettsii, which leads to a characteristic rash that often starts at the extremities and progresses towards the center of the body. The fever commonly associated with RMSF typically appears suddenly, accompanied by a severe headache and other symptoms such as nausea and vomiting. The rash begins as small, flat, and pink spots (macules) that eventually develop into petechiae, which can give the appearance of small red or purple spots due to bleeding under the skin, especially as the condition progresses. In contrast, Kawasaki disease primarily involves prolonged fever and specific mucosal findings along with rash, often affecting the palms and soles but with a very distinct set of symptoms that include conjunctivitis and changes to the lips and tongue. Meningococcemia may present with a petechial rash but usually includes systemic symptoms like severe leg pain, a rapid onset of sepsis, and purpura rather than a rash that spreads from distal to proximal. Measles features a characteristic koplik spots, a different progression of rash,