Section of Pulmonology, Department of Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas, USA.
J Heart Lung Transplant. 2012 Dec;31(12):1288-92. doi: 10.1016/j.healun.2012.09.010. Epub 2012 Oct 25.
Bronchiolitis obliterans (BO) is the major obstacle to long-term lung allograft viability. Its clinical correlate, BO syndrome (BOS), is defined as a decline of at least 20% in forced expiratory volume in 1 second (FEV(1)) from baseline. BOS is often diagnosed after significant organ dysfunction has occurred. Because BO is a small-airways disease, we hypothesized that a 20% decline in the 25% to 75% forced expiratory flow (FEF(25-75)) from baseline should occur before a decline in FEV(1) and should predict progression to BOS with high sensitivity and specificity.
Pulmonary function tests and records of pediatric lung transplantation patients at Texas Children's Hospital from 2002 to 2007 were reviewed. Declines in FEV(1) and FEF(25-75) from the best post-transplant baseline values were recorded and analyzed. Sensitivity, specificity, and positive and negative predictive values were calculated.
Thirty-one patients were eligible for the study. In 11 BOS patients, the mean±standard deviation number of days from transplant until a 20% decline in FEV(1) was 896.5±400 compared with 728.0±475 (p = 0.022) until a 20% decline in FEF(25-75) was reached. The sensitivity, specificity, and positive predictive and negative predictive values of a 20% reduction in FEF(25-75) in determining BOS were 100%, 90.0%, 84.6%, and 100%, respectively.
All patients who developed BOS had a decline in FEF(25-75) at or before the decline in FEV(1). The reduction in FEF(25-75) occurred statistically significantly earlier than the decline in FEV(1), by an average of 168.5 days. This decline in FEF(25-75) was also highly sensitive and specific for the diagnosis of BOS.
闭塞性细支气管炎（BO）是长期肺移植存活的主要障碍。其临床相关疾病，BO 综合征（BOS），定义为用力呼气量（FEV1）基线值下降至少 20%。BOS 通常在发生显著器官功能障碍后诊断。由于 BO 是一种小气道疾病，我们假设从基线开始，25%至 75%用力呼气流量（FEF25-75）下降 20%，应该先于 FEV1 下降，并应该具有高灵敏度和特异性来预测进展为 BOS。
回顾 2002 年至 2007 年德克萨斯儿童医院小儿肺移植患者的肺功能检查和记录。记录并分析了从最佳移植后基线值下降的 FEV1 和 FEF25-75。计算了灵敏度、特异性、阳性和阴性预测值。
31 名患者符合研究条件。在 11 名 BOS 患者中，从移植到 FEV1 下降 20%的平均±标准偏差天数为 896.5±400 天，而到 FEF25-75 下降 20%的平均±标准偏差天数为 728.0±475 天（p = 0.022）。FEF25-75 下降 20%预测 BOS 的灵敏度、特异性、阳性预测值和阴性预测值分别为 100%、90.0%、84.6%和 100%。
所有发生 BOS 的患者在 FEV1 下降之前或同时出现 FEF25-75 下降。FEF25-75 的下降在统计学上早于 FEV1 的下降，平均早 168.5 天。FEF25-75 的这种下降对 BOS 的诊断也具有很高的灵敏度和特异性。
