Fever of unknown origin. Comparison of the diagnostic spectrum of 53 cases in a medical ward in an Italian hospital with those of other 9 countries]

In the Institute of Medical Pathology of Ancona University, 53 cases of fever of unknown origin (FUO) were reviewed. In 44 cases (83%) the diagnosis was certainly stated. The diagnostic spectrum of the diagnosed cases was: 31 infectious (58%), 3 neoplastic (6%), 8 autoimmune (15%), 2 miscellaneous diseases (4%). Nine cases (17%) were undiagnosed. The mortality rate of the diagnosed cases was 16% within 16 months. The diagnostic spectrum, compared with the FUO series from nine countries, is unlike because of a higher rate of infectious diseases and a lower rate of neoplastic diseases. The methods, successfully used to achieve the final diagnosis were: laboratory tests, including bacteriologic studies, in 39%, evaluation of the clinical course and follow-up in 25%, imaging scan tests, including radionuclide, ultrasound, magnetic resonance, computed tomography, in 23%, and anatomopathological studies in 13%. A three years' follow-up was successfully carried out in 7 out of the 9 undiagnosed patients: 5 were healed without any treatment, 1 healed through a course of non steroid anti-inflammatory drugs and only one died because of the FUO carrying disease. None was persistently sick. The data are discussed through a comparison with the series of FUO bearing patients from other 9 countries.