Clinical data of 3 patients each with acute exacerbation of interstitial pneumonia (NsIP). Five of the cases were the result of the pathology of interrogative pneumonia before the acute exacerbation, and l case was the result of the autopsy after the acute exacerbation. The results were 2 males and 4 females in 6 cases, aged 29 to 57 years (median age 51 years). The pathological findings before the acute exacerbation were: uIP in 3 cases (1 idiopathic, 1 secondary to dermatomyositis, 1 secondary to connective tissue disease), NsIP in 2 cases (1 idiopathic, 1 secondary to dermatomyositis), and diffuse alveolar injury combined with NsIP (secondary to dermatomyositis) in 1 case at autopsy. 2 of the 6 cases had undergone thoracoscopic lung biopsy 1 week before the acute exacerbation, 5 cases had fever, 2 cases had increased white blood cell Sputum and blood cultures were not positive in 6 cases. The oxygenation index at acute exacerbation was 200 mm Hg (interquartile range 158-237 mm Hg, 1 mm Hg = O.133 kPa), EsR was increased in 4 cases, and c-reactive protein was elevated in 2 cases. Chest cT showed ground glass and solid shadows on top of the original lesion. 5 cases were treated with glucocorticoids 35-1000 m∥d, 2 cases were treated with intravenous human gammaglobulin, 4 cases died during hospitalization, 3 patients with invasive mechanical ventilation died, 1 surviving discharge was stable, 1 case improved, and the next 2 cases were lost to follow-up. Conclusion Both uIP and NsIP can present with acute exacerbation, with clinical manifestations of sudden onset of dyspnea and fever, with no specificity and unclear causative factors, and no response to broad-spectrum antibiotic therapy, and treatment with high-dose glucocorticoids and intravenous human gammaglobulin may be effective.