Table 3

The association of patient demographics, clinical characteristics and diagnostic evaluation between patients with known and unknown causes of FUO

VariablesKnown cause*Unknown cause*OR (95% CI)P value†
Age group≥65 years53 (81.5%)12 (18.5%)0.73 (0.32 to 1.66)0.451
<65 years58 (76.3%)18 (23.7%)1.00
SexMale48 (76.2%)15 (23.8%)1.31 (0.59 to 2.95)0.510
Female63 (80.8%)15 (19.2%)1.00
ComorbidityYes69 (78.4%)19 (21.6%)1.03 (0.44 to 2.37)0.951
No41 (78.8%)11 (21.2%)1.00
Symptoms
 HeadacheYes17 (73.9%)6 (26.1%)1.35 (0.48 to 3.80)0.566
No92 (79.3%)24 (20.7%)1.00
 Chest painYes2 (66.7%)1 (33.3%)1.85 (0.16 to 20.07)0.622
No107 (78.7%)29 (21.3%)1.00
 Respiratory symptomsYes19 (79.2%)5 (20.8%)1.01 (0.34 to 2.98)0.987
No92 (79.3%)24 (20.7%)1.00
 Gastrointestinal symptomsYes14 (66.7%)7 (33.3%)2.09 (0.76 to 5.76)0.155
No96 (80.7%)23 (19.3%)1.00
 Stomach acheYes12 (85.7%)2 (14.3%)0.58 (0.12 to 2.73)0.489
No97 (77.6%)28 (22.4%)1.00
 ArthralgiaYes38 (86.4%)6 (13.6%)0.47 (0.18 to 1.24)0.127
No71 (74.7%)24 (25.3%)1.00
 Muscle painYes15 (78.9%)4 (21.1%)0.95 (0.29 to 3.12)0.938
No93 (78.2%)26 (21.8%)1.00
 Lymph node enlargementYes13 (86.7%)2 (13.3%)0.53 (0.11 to 2.50)0.425
No97 (77.6%)28 (22.4%)1.00
 RashYes26 (81.3%)6 (18.8%)0.82 (0.30 to 2.21)0.692
No85 (78.0%)24 (22.0%)1.00
Ancillary findings
 WBCYes111 (78.7%)30 (21.3%)NANA
No0 (0%)0 (0%)
 CRPYes111 (78.7%)30 (21.3%)NANA
No0 (0%)0 (0%)
 ESRYes86 (74.8%)29 (25.2%)8.43 (1.09 to 65.00)0.041
No25 (96.2%)1 (3.8%)1.00
 ProcalcitoninYes41 (75.9%)13 (24.1%)1.31 (0.58 to 2.96)0.523
No70 (80.5%)17 (19.5%)1.00
 Blood cultureYes96 (76.8%)29 (23.2%)4.53 (0.57 to 35.78)0.152
No15 (93.8%)1 (6.3%)1.00
 AutopsyYes4 (66.7%)2 (33.3%)1.88 (0.33 to 10.77)0.481
No105 (78.9%)28 (21.1%)1.00
 PETYes33 (75.0%)11 (25.0%)1.37 (0.59 to 3.19)0.468
No78 (80.4%)19 (19.6%)1.00
 Ga scintigraphyYes29 (72.5%)11 (27.5%)1.64 (0.70 to 3.85)0.258
No82 (81.2%)19 (18.8%)1.00
  • Stomach ache is different from gastrointestinal symptoms, which include vomiting and diarrhoea.

  • *Percentage was calculated as the number of patients who received an examination divided by the total patients for each condition.

  • †χ² tests were performed.

  • CRP, C reactive protein; ESR, erythrocyte sedimentation rate; Ga, gallium; PET, positron emission tomography; WBC, white blood cell count.