The pathogeny constituent analysis of fever of unknown origin in adult patients:Chinese literature review from 1990 to 2013

Objective: To review the etiology in 4 582 adult patients with fever of unknown origin(FUO) in Chinese literature from 1990 to 2013, and compare the differences between north and south areas and changes in different periods. Methods: Four thousand five hundred and eighty-two patients with FUO in 21 clinical research literatures from 1 360 literatures searched from China National Knowledge Infrastructure(CNKI) database containing the key word "fever of unknown origin" from 1990 to 2013. The data were analyzed according to the difference between north and south areas, and changes in early period(1990 to 2003) and later period(2004 to 2013). Results: Among the 4 582 FUO cases, the definite diagnosis was 90.9%. The most common cause of FUO was the infectious disease(54.4%), and the tuberculosis was more common(16.2%). The patients with rheumatic autoimmune disease accounted for 15.5%, adult Still's disease (5.6%) was more common. The tumor(more common in 4.5% lymphoma), miscellaneous causes(more common in 3.1% of drug-induced fever) and unknown reason accounted for 13.2%, 7.8% and 9.1%, respectively. The proportions of infectious disease and tumor in the South were significantly higher than those in the North(P<0.01 and P<0.05). The proportions of rheumatic autoimmune disease, drug-induced fever and miscellaneous causes in the South were lower than those in the North(P<0.01). The pathogeny proportions of the infectious disease, drug-induced fever and miscellaneous cause in early period of FUO were significantly lower than those in later period(P<0.01), while the pathogeny proportions of the viral disease, tumor and miscellaneous cause in early period of FUO were significantly higher than those in later period (P<0.01). Conclusions: The infectious disease is the most common cause of FUO. There are some differences in pathogeny constituent between north and south areas, which changes over time.