Liu Yin, Chen Lu Lu, Qiu Yu Ying, Xiao Yong Long, Cai Hou Rong
Department of Respiratory, Drum Tower Hospital, Nanjing University Medical School, Nanjing, Jiangsu, China.
Medicine (Baltimore). 2017 Nov;96(44):e8481. doi: 10.1097/MD.0000000000008481.
Pulmonary alveolar proteinosis (PAP) is a rare lung disorder characterized by the abnormal accumulation of alveolar surfactant protein in alveolar spaces. Secondary PAP can result from myelodysplastic syndrome (MDS).
But most reports described a single case; here we reported 2 cases of PAP secondary to MDS. One case developed secondary PAP at the same time as MDS, and the other developed during the course of MDS.
The diagnosis of PAP was made by bronchoalveolar lavage and based on the identification of periodic acid-Schiff-positive proteinaceous material. Chest high resolution CT (HRCT) scans showed variable distribution of ground glass opacities, but crazy-paving appearance was not seen in our 2 cases.
Because the patients' general conditions were poor, whole lung lavage was not used in the 2 cases.
And the 2 cases' prognoses were poor.
In conclusion, pulmonary physicians should suspect the possibility of secondary PAP when they encounter unexplained pulmonary infiltrates with some hematologic or infectious disease that shows diffuse bilateral GGO on an HRCT scan.
肺泡蛋白沉积症（PAP）是一种罕见的肺部疾病，其特征是肺泡表面活性物质蛋白在肺泡腔内异常蓄积。继发性PAP可由骨髓增生异常综合征（MDS）引起。
但大多数报告描述的是单个病例；在此我们报告2例继发于MDS的PAP。1例在诊断MDS的同时发生继发性PAP，另1例在MDS病程中发生。
PAP的诊断通过支气管肺泡灌洗并基于过碘酸雪夫染色阳性的含蛋白质物质的鉴定。胸部高分辨率CT（HRCT）扫描显示磨玻璃影分布多样，但我们的2例患者均未见铺路石征。
由于患者一般情况较差，这2例患者未采用全肺灌洗。
这2例患者预后较差。
总之，肺科医生在遇到原因不明的肺部浸润且伴有某些血液系统疾病或感染性疾病，同时HRCT扫描显示双肺弥漫性磨玻璃影时，应怀疑继发性PAP的可能性。
