Young Woman With Calf Pain and Fever of Unknown Origin

Aug 24, 2013

She presented with such severe calf pain she could no longer walk unassisted, with a months-long history of fever of unknown origin. What does the MRI show?

An 18-year-old Hispanic female with no significant medical history presented to our hospital with severe, debilitating pain and weakness in both calves, intermittent fevers over the past three months, drenching night sweats, and new-onset upper extremity bilateral weakness and pain during the previous three weeks.  Her fevers, which had increased from once weekly to twice daily over the past month, usually arrived in the afternoon, with associated chills, frontal headache, nausea, photophobia, phonophobia, and dizziness.  She also reported decreased appetite and a 5 kg weight loss over the prior six months.

The calf pain and weakness had begun four months earlier, concurrent with an upper respiratory infection that resolved within two weeks. This episode was not associated with cough, fever, chills, or night sweats. She had no prior history of respiratory problems. 

An MRI image of the right calf appears above. What do you think it shows? What other symptoms would you expect to see, and which further tests would you order?

Click here to see the diagnosis and complete case study.



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