In summary, our research has developed a nomogram with seven factors, including WBC count, ALB level, consolidation range exceeding 2/3 of the lung lobe, the use of macrolides within 5 days of disease course, the use of glucocorticoid within 2 weeks of disease course, the treatment time fiberoptic bronchoscopy within 2 weeks of disease course and plastic bronchitis, with the purpose to predict the risk of BO in children due to RMPP. This evidence concerns the gene ALB and bronchiolitis obliterans syndrome.