Two weeks following a hiking trip in which several ticks were noticed and numerous mosquitoes were biting,a 25-year-old man notices a rash shaped like a red ring on the back of his thigh.He was not concerned because he had no other symptoms.Three months later he noticed significant pain in his elbows and his knees.What is the most likely cause of his illness?

Question

Quizplus · Accepted Answer

The presence of a red ring-shaped rash following tick bites and subsequent joint pain in multiple joints suggests the diagnosis of Lyme disease, which is caused by the bacterium Borrelia burgdorferi transmitted by deer tick bites. West Nile encephalitis is caused by a virus transmitted by mosquitoes and typically presents with fever, headache, and neurologic symptoms. Rocky Mountain Spotted Fever and Ehrlichiosis are bacterial infections also transmitted through tick bites but do not typically present with joint pain specifically, making Lyme disease the most likely diagnosis in this case.

Two Weeks Following a Hiking Trip in Which Several Ticks