Original Article
Diagnostic value of antineutrophil cytoplasmic antibodies in children with bronchiolitis obliterans
Abstract
Background: Diagnosis of childhood bronchiolitis obliterans (BO) is difficult owing to non-specific clinical presentations and limited investigational options. There is a lack in established serum biomarkers for BO. While the diagnostic value of antineutrophil cytoplasmic antibodies (ANCAs) has been discussed, little is known about this in BO. We aimed to investigate the serological profiles of ANCAs against myeloperoxidase (MPO-ANCA) and proteinase-3 (PR3-ANCA) in BO and acute pneumonia.
Methods: In this study, 42 BO children (BO group) and 43 with mild acute pneumonia (pneumonia group) were included, based on rigorous diagnostic criteria and additional constraints for minimizing selection bias. Serum MPO-ANCA and PR3-ANCA levels were measured on the first (baseline) and the last day of hospitalization (on discharge) by enzyme linked immunosorbent assay.
Results: Although the BO children had a longer hospital stay, the overall rate of positivity (≥180 AAU/mL) and median serum level of MPO-ANCA were higher in the BO group compared with the pneumonia group, either at baseline (69.1% vs. 9.3%, 292.00 vs. 104.75 AAU/mL, both P<0.001) or on discharge (61.9% vs. 9.3%, 310.50 vs. 95.42 AAU/mL). Similar was found for PR3-ANCA (38.1% vs. 4.7%, 106.66 vs. 54.56 AAU/mL at baseline; 35.7% vs. 2.3%, 97.98 vs. 57.23 AAU/mL on discharge, both P<0.001). There were a higher rate of dual-positivity and a lower rate of dual-negativity to both ANCAs in the BO group than those in the pneumonia group (all P<0.001).
Conclusions: Detection of MPO- and PR3-ANCA can help diagnosis of childhood BO.
Methods: In this study, 42 BO children (BO group) and 43 with mild acute pneumonia (pneumonia group) were included, based on rigorous diagnostic criteria and additional constraints for minimizing selection bias. Serum MPO-ANCA and PR3-ANCA levels were measured on the first (baseline) and the last day of hospitalization (on discharge) by enzyme linked immunosorbent assay.
Results: Although the BO children had a longer hospital stay, the overall rate of positivity (≥180 AAU/mL) and median serum level of MPO-ANCA were higher in the BO group compared with the pneumonia group, either at baseline (69.1% vs. 9.3%, 292.00 vs. 104.75 AAU/mL, both P<0.001) or on discharge (61.9% vs. 9.3%, 310.50 vs. 95.42 AAU/mL). Similar was found for PR3-ANCA (38.1% vs. 4.7%, 106.66 vs. 54.56 AAU/mL at baseline; 35.7% vs. 2.3%, 97.98 vs. 57.23 AAU/mL on discharge, both P<0.001). There were a higher rate of dual-positivity and a lower rate of dual-negativity to both ANCAs in the BO group than those in the pneumonia group (all P<0.001).
Conclusions: Detection of MPO- and PR3-ANCA can help diagnosis of childhood BO.
