急性细支气管炎主要侵犯幼儿,常见病因为呼吸道合胞体病毒,通常可完全恢复。在成人中,这种感染可能亦很常见,但是由于支气管树解剖上的差异,气道阻塞不大明显。细支气管改变常见于慢性支气管炎和肺气肿,并可伴有纤维性肺泡炎。闭塞性细支气管炎(obliterative bronchiolitis,OB)可分为3型:①与感染(通常为病毒)有关;②因暴露于毒性烟雾引起;③病因不明。前两型通常为急性发病,缓解后1～3周,有缓慢发生的呼吸短促。Gosink 等报道,大多数由各种病因引起的局限型和广泛型 OB 患者用皮质类固醇治疗后好转。在毒性烟雾所致 OB 中,二氧化氮是最常见的致病因子。二氧化氮可从青饲料中释出,引起农民中的“青饲料仓库工作者肺”,在暴露后2～3周内发生细支气管炎,用皮质类固醇治疗迅速奏效。儿童腺瘸毒感染偶可导致广泛性细支气管闭塞。病因不明的 OB 开始无急性发病,病程通常较缓慢。近6年来报道类风湿性关节炎患者中发生严重OB 病例,OB 似与类风湿性关节炎有关,亦有报道 Acute bronchiolitis mainly infants, the common cause of respiratory syncytial virus, usually can be completely restored. This infection may also be common in adults, but airway obstruction is less pronounced due to the anatomical differences in the bronchial tree. Bronchioles are common in chronic bronchitis and emphysema and may be associated with fibrosing alveolitis. Obstructive bronchiolitis (obliterative bronchiolitis, OB) can be divided into three types: ① and infection (usually a virus); ② due to exposure to toxic smoke; ③ etiology is unknown. The first two types are usually acute, 1 to 3 weeks after remission, there is a slow onset of shortness of breath. Gosink et al reported that most of the limitations caused by a variety of causes and extensive OB patients treated with corticosteroids improved. Nitric oxide is the most common causative agent in OB induced by toxic smoke. Nitrogen dioxide can be released from green fodder, causing “green fodder warehouse worker lungs” among peasants. Bronchiolitis occurs within 2 to 3 weeks after exposure and corticosteroid treatment works quickly. Children with adeno-melatonin infection even lead to extensive bronchiolar obliteration. OB unknown etiology of acute onset, the course is usually slower. It has been reported that severe OB cases occur in patients with rheumatoid arthritis in the past 6 years, and OB seems to be associated with rheumatoid arthritis