The Case of the Returning Fever

A 22-year-old man presents with high fevers, rigors, severe headache, diffuse myalgias, and profound weakness. He recently arrived in Europe after traveling from the Horn of Africa through multiple crowded transit settings. He reports poor access to bathing and frequent itching with scratching of his trunk and clothing seams during the journey.

He describes an abrupt febrile illness about one week ago that seemed to improve after several days, followed by an afebrile interval. He now has recurrent fever with worsening malaise, epistaxis, and upper abdominal discomfort. He denies known tick exposure. No prior medical history is available, and he is not taking medications.

On examination, he appears ill and dehydrated. Temperature is 39.8 C, heart rate 122/min, blood pressure 96/60 mmHg, and respiratory rate 24/min. He has scleral icterus, scattered petechiae over the trunk, dried blood at the nares, hepatic tenderness, and mild splenomegaly. Scratch marks are present on the torso, and body louse infestation is suspected based on visible nits and insects within clothing seams.

Initial laboratory studies show hemoglobin 9.6 g/dL, leukocytes 12.8 x10^9/L, platelets 46 x10^9/L, total bilirubin 4.3 mg/dL (direct 2.1 mg/dL), AST 112 U/L, ALT 74 U/L, creatinine 1.4 mg/dL, and CRP 146 mg/L. A thick and thin Giemsa-stained blood smear obtained while febrile demonstrates numerous long extracellular spirochaetes.