Increased B-cell Activating Factor Levels in Children with Acute Brucellosis

Objective: Brucellosis is a chronic infectious disease. We aimed to show the association of serum 'A PRoliferation-Inducing Ligand (APRIL) (TNFSF13A)' and 'B-cell Activating Factor (BAFF)' levels belonging to the tumor necrosis factor family in children with acute brucellosis. Methods: Fifty children with acute brucellosis and 35 healthy controls who were admitted during a two-year period between 2018 and 2020 were prospectively included in the study. All patients and healthy children were tested for complete blood counts, C-reactive protein, BAFF, and APRIL levels, and erythrocyte sedimentation rate. Results: The mean age of 50 patients with acute brucellosis was 10.2 +/- 3.6 years, and 37 (74%) of them was male. BAFF levels were significantly higher in children with acute brucellosis than the control group (548.6 +/- 253.4 vs. 280.5 +/- 83.6, p<0.001). In addition to APRIL levels, other laboratory tests were not statistically significantly different between the patients and control group. Neither BAFF and APRIL, nor age, gender, Rose-Bengal test results, transaminase levels, and other laboratory parameters were significantly different between the patients with and without any complication(s). ROC analysis showed that BAFF values above 330 pg/mL were 78% sensitive and 72% specific for the detection of acute brucellosis in children (area under curve:0.864, p<0.001, CI:0.787-0.941). Conclusion: BAFF levels were significantly elevated in children with acute brucellosis. BAFF levels above 330 pg/mL were 78% sensitive and 72% specific for the detection of the disease, but BAFF could not discriminate between patients with and without complications. APRIL, which has relatively similar effects, is not associated with acute pediatric brucellosis.