Microbiology – Medical Question:

A 14-year-old girl who returned a few days ago from a school camping trip in North Carolina is home ill from school. She has a headache and chills. Next few days, she develops a rash that starts on her palms and soles, but spreads inward to her wrists and ankles and then to her trunk. Her worsening condition causes her parents to take her to the emergency department, where a blood test reveals antibodies that react with the Proteus antigen. This patient is most likely infected with which of the following?

A. Rickettsia typhi
B. Treponema pallidum
C. Coxiella burnetti
D. Borrelia burgdorferi
E. Rickettsia rickettsia
F. Coxsackievirus A

First Aid Q&A for step 1 ©

[expand title=”CLICK HERE VIEW CORRECT ANSWER:”][sociallocker]The correct answer is E. This patient most likely has Rocky Mountain spotted fever, as indicated by the rash on her palms and soles and the inward, “centripetal” pattern of spread. Other supporting evidence are the accompanying headache and fever, and a positive Weil- Felix reaction, which is a cross-reaction of certain anti-rickettsial antibodies with the Proteus antigen. Rocky Mountain spotted fever is caused by the rickettsial organism Rickettsia rickettsii, and is endemic to the east coast of the United States. It is transmitted by the Ixodes tick, thus the patient probably acquired it during her recent camping trip.[/sociallocker][/expand]