TY - CHAP M1 - Book, Section TI - Prolonged Fever and Fever of Unknown Origin A1 - Shah, Samir S. A1 - Alpern, Elizabeth R. A2 - Zaoutis, Lisa B. A2 - Chiang, Vincent W. Y1 - 2017 N1 - T2 - Comprehensive Pediatric Hospital Medicine, 2e AB - In 1961, Petersdorf and Beeson proposed their now classic criteria for fever of unknown origin (FUO): (1) an illness of at least 3 weeks’ duration, (2) measured temperatures greater than 38.3°C on several occasions, and (3) no etiologic diagnosis after 1 week of hospitalization.1 For adult patients, Durack and Street2 modified the third criterion of this definition to account for potential outpatient evaluation by substituting “3 outpatient visits or at least 3 days in the hospital” for “1 week of hospitalization.” Studies focusing on pediatric patients have occasionally used fever duration of 2 rather than 3 weeks. Patients presenting with 2 to 3 weeks of fever but not meeting all the criteria for FUO are often referred to as having prolonged fever. Differentiating prolonged fever from FUO can be impractical, because the diagnostic criteria for FUO do not specify the type or extent of evaluation required. Final diagnoses are determined in a number of ways (e.g. natural history, biopsy, imaging, serologic studies) and no single patient either receives or requires every diagnostic test. This chapter discusses the evaluation of a child with prolonged fever in whom the cause of fever is not readily apparent. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accesspediatrics.mhmedical.com/content.aspx?aid=1146118155 ER -