肺淋巴管平滑肌瘤病的光镜和电镜观察

为探讨肺淋巴管平滑肌瘤病（PLAM）超微结构的特点，对1例经电视胸腔镜肺活检诊断为PLAM的病例进行光镜和电镜观察、免疫组化检测。患者女性，44岁，临床主要表现为进行性加重的活动后呼吸困难、胸闷和自发性气胸；高分辨CT表现为两肺弥漫性网织蜂窝样改变。光镜观察：胸膜下和肺间质大量的平滑肌增生，肺泡壁增厚，肺泡腔扩张。免疫组化显示增生的平滑肌细胞波形蛋白、肌动蛋白和平滑肌肌动蛋白染色阳性。在透射电镜下能清楚显示淋巴管结构以及内皮细胞下大量增生的平滑肌细胞。结论：PLAM的明确诊断依赖于肺活检病理诊断。免疫组化检测和电镜观察具有重要的病理诊断和鉴别诊断价值。

Light microscopic and electron microscopic observation of pulmonary lymphangioleiomyomatosis

To investigate the ultrastructural features of pulmonary lymphangioleiomyomatosis(PLAM),the video-assisted thoracoscopic lung biopsy of a patient with PLAM was observed under the light microscope(LM) and electron microscope(EM),and examined by immunohistochemistry.The patient was a 44 year old female and presented with progressive dyspnoea on exertion and chest distress and spontaneous aeropleura.High resolution computerized tomography showed diffuse honeycombing in her both lungs.Findings of LM were a number of hyperplasia of smooth muscles in pleural membrane and alveolar septa,and thickening of alveolar wall and distention of alveolar spaces.The cells were stained positively by vimentin, desmin and smooth muscle actin,and negatively by cytokeratin and epithelial membrane antigen.EM observation showed distention of lymph vessels in the alveolar interstitium,and there were a great number of hyperplastic smooth muscle cells around them.The pathological diagnosis of PLAM is depended on the lung biopsy.Immunohistochemistry examination and EM observation are very helpful for the pathological diagnosis and differential diagnosis.