纵隔气肿常继发于张力性气胸。由间质性肺炎所致的单纯性纵隔气肿在临床上非常少见，国内仅报道过两例 [1]。最近我们收治了 1例由支原体肺炎引起的单纯性纵隔气肿。在此，结合本病例复习有关文献，对该病的发病机理、诊断及治疗进行讨论。 1.临床资料 患者，男，农民， 18岁 Mediastinal emphysema often secondary to tension pneumothorax. Simple interstitial pneumonia caused by simple mediastinal emphysema is clinically very rare, only two reported in China [1]. Recently, we treated 1 case of simple mediastinal emphysema caused by mycoplasma pneumonia. Here, with reference to the literature review of the case, the pathogenesis of the disease, diagnosis and treatment are discussed. 1. Clinical data Patients, male, peasant, 18 years old