Faculty of Medicine, Pediatrics Department, Ain Shams University, Cairo, Egypt.
Clinical Pathology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
Pediatr Pulmonol. 2019 May;54(5):610-619. doi: 10.1002/ppul.24257. Epub 2019 Jan 22.
Surfactant protein D (SP-D) is considered a candidate biomarker for lung integrity and for disease progression.
We determined the level of SP-D in children and adolescents with SCD and assessed its possible relation to pulmonary complications and lung function.
Serum SP-D levels were assessed in 50 SCD patients compared with 30 healthy controls. High-resolution computerized tomography (HRCT) of the chest was done. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV ), FEV /FVC% and forced expiratory flow rate during 25-75% of expiration (FEF25-75%) were determined.
SP-D was significantly higher in SCD patients than controls, particularly patients with sickle cell anemia than those with sickle β-thalassemia. SP-D levels were significantly associated with increasing severity of interstitial lung disease. The highest SP-D levels were observed among patients with restrictive lung disease followed by mixed type then obstructive lung disease. SP-D was positively correlated to HbS and serum ferritin while negatively correlated to duration of hydroxyurea treatment and parameters of pulmonary functions. ROC curve analysis revealed that SP-D cutoff value 720 ng/mL could significantly detect the presence of abnormal pulmonary function among SCD patients with 82% sensitivity and 88% specificity. Logistic regression analysis showed that SP-D is an independent factor related to abnormal pulmonary function in SCD.
SP-D may be a promising biomarker for screening of SCD patients for risk of later pulmonary complications.
表面活性蛋白 D（SP-D）被认为是肺完整性和疾病进展的候选生物标志物。
我们测定了 SCD 患儿和青少年的 SP-D 水平，并评估其与肺部并发症和肺功能的可能关系。
将 50 例 SCD 患者与 30 例健康对照者进行比较，评估血清 SP-D 水平。行胸部高分辨率计算机断层扫描（HRCT）。测定用力肺活量（FVC）、第 1 秒用力呼气量（FEV ）、FEV/FVC%和 25%-75%呼气流速（FEF25-75%）。
SCD 患者的 SP-D 明显高于对照组，尤其是镰状细胞贫血患者高于镰状细胞β-地中海贫血患者。SP-D 水平与间质性肺病严重程度呈显著正相关。在限制性肺疾病患者中观察到最高的 SP-D 水平，其次是混合性然后是阻塞性肺疾病。SP-D 与 HbS 和血清铁蛋白呈正相关，与羟基脲治疗时间和肺功能参数呈负相关。ROC 曲线分析显示，SP-D 截断值 720ng/ml 可显著检测出 SCD 患者异常肺功能的存在，其敏感性为 82%，特异性为 88%。Logistic 回归分析显示，SP-D 是 SCD 患者异常肺功能的独立相关因素。
SP-D 可能是筛查 SCD 患者发生肺部并发症风险的有前途的生物标志物。
