Comprehensive Evaluation Of Etiology And Related Factors Of Patients With Fever Of Unknown Origin

ObjectiveTo investigate distribution of disease categories in Fever of unknown origin(FUO) and clinical characteristics by compared with Inflammation of unknown origin(IUO); deepen understanding of temperature limits of diagnosis of FUO.MethodsOne hundred and eighty-seven patients of FUO, thirty-two patients of IUO andsixty-six patients of prolonged fever with temperature <38.3℃admitted to ChinesePLA General Hospital were included in this study. Retrospective analysis the etiologydistribution, heating characteristics, auxiliary examination between them. Theirtemperature-related factors were analyzed by multivariate logistic regression analysisrespectively.ResultsThe diagnostic rate of the FUO group was81.3%, including infectious diseases109cases (58.3%).Connective tissue diseases25cases (13.4%);Malignant tumor9cases (4.8%). Compared with the lower-temperature fever group, the IUO groupexcluding functional fever (6cases), fever after infection (6cases), urinary tractinfection (7cases) by setting the value of ESR and CRP. From that, the patients ofIUO group was similar with the FUO group on the etiology distribution, heatingcharacteristics and auxiliary examination. The diagnostic rate of the IUO group was78.1%, including infectious diseases16cases (50%).Connective tissue diseases5cases (15.6%);Malignant tumor2cases (6.3%);The other2cases (6.3%). The patientsof FUO were younger than that of IUO (p=0.015); Chills (p=0.001),(p=0.009)and lymph node enlargement (p=0.039) were more in the FUO group. The FUO group has a higher PCT (p=0.005), ALT (p=0.014), AST (p=0.004), LDH (p=0.001), SF (p=0.048). The IUO group with blood sedimentation (p=0.031),endotoxin (p=0.044) index rise more obvious. There were no obvious difference (p>0.05) between the two groups of WBC, N, HB, PLT, CRP, IL-6, AKP, ALB.Multivariate logistic regression analysis results showed that the ESR (P=0.022) andchills (P=0.001) are the temperature-related factors between FUO and IUO group；the sex（P<0.001）,LDH（P<0.001）and chills （P<0.001）are the temperature-relatedfactors between FUO and lower-temperature fever group.ConclusionThis research shows that, infectious diseases is still the most common cause ofFUO followed by connective tissue diseases, malignant tumors and other classes. ESR,chills, sex and LDH maybe the temperature-related factors. Although IUO group wassimilar with the FUO group by setting the value of ESR and CRP, there were still acertain statistical differences between IUO and FUO on of etiology, clinical symptomsand laboratory examination, so we could not think IUO is another kind of FUO.