[Analysis of cost-effectiveness in the diagnosis of fever of unknown origin and the role of (18)F-FDG PET-CT: a proposal of diagnostic algorithm].

AIM To analyze the costs of Fever of Unknown Origin (FUO) prior to the PET-CT study. To determine the effectiveness of PET-CT in the diagnosis of FUO. A proposal of diagnostic algorithm. MATERIAL AND METHODS A retrospective study was performed that included 20 patients who had been studied between January 2007 and January 2011, with a mean age of 57.75 years and FUO diagnosis. All underwent a PET-CT study with (18)F-FDG. Individual and mean costs of FUO in these patients were assessed, including hospitalization days and complementary tests prior to the PET-CT study. The effectiveness of the PET-CT study in the diagnosis of FUO was analyzed. Costs of the FUO process were determined, including those of the PET-CT study, and if it had been done earlier in the diagnostic process. RESULTS Mean hospital stay per patient until the PET-CT study was 28 days. The cost per hospitalization day was 342 €. Average cost per patient in complementary tests was 1395 €. Total cost of the FUO process until the PET-CT study was around 11167 € per patient. The PET-CT study showed a 78% sensitivity, 83% specificity, 92% PPV and 62% NPV. If PET-CT had been performed earlier in the FUO process, assuming the same effectiveness, 5471 € per patient would have been saved. CONCLUSION The PET-CT study could be cost-effective in the FUO process if used at an early stage, helping to establish an early diagnosis, reducing hospitalization days due to diagnostic purposes and the repetition of unnecessary tests.