Question

A 24-year-old female presents with a rash to her left leg and swollen, painful knee joints. She tells you that she and her friends returned from a hiking trip in the mountains a week ago. She is conscious and alert with a blood pressure of 112/62 mm Hg, a pulse of 84 beats/min, and respirations of 14 breaths/min. Her symptoms are MOST likely the result of:

a) Lyme disease
b) Heat exhaustion
c) Food poisoning
d) Acute mountain sickness

Answer 1

The symptoms are most likely caused by Lyme disease, considering the recent hiking trip, the presence of a rash and swollen knee joints, and the fact that these symptoms align with the early stages of Lyme disease.

Step-by-step explanation:

The 24-year-old female's symptoms, which include a rash on her leg, swollen and painful knee joints, as well as recent hiking in the mountains, are most likely the result of Lyme disease. This is supported by the details provided in several Clinical Focus boxes, which describe similar cases of individuals who developed symptoms consistent with Lyme disease after spending time in wooded areas. The described symptoms, such as a rash, joint pain, fever, headache, and fatigue, match the early localized and early disseminated stages of Lyme disease caused by the bacterium Borrelia burgdorferi. The characteristic bull's-eye rash, even though not mentioned in the student's scenario, is not present in 20-30% of Lyme disease cases, and thus its absence cannot rule out the diagnosis.