Participants
The diagnosis of FUO was made according to the classic Petersdorf’s
criteria, body temperature >38.3°C on several occasions for
at least 3 weeks with no diagnosis despite one week of inpatient or
outpatient work-up [1]. This work-up included a thorough history and
physical examination, a complete blood count, blood chemistry, blood
cultures, hepatitis serologies in the case of abnormal liver tests,
urinalysis, and a chest radiograph. In those patients who were admitted,
the workup also included more extensive inflammatory and infectious
serologies, and abdominal ultrasound or CT.
In our facility, PET/CT was not considered a standard part of the
initial workup for patients with FUO, and its usage was preserved for
those without a diagnosis despite a complete work-up. Study exclusion
criteria were age below 18 years, pregnancy, insufficient data from
medical records, active solid or hematologic malignancy, neutropenia,
nosocomial infections, or HIV carrying status.