Abstract
Bronchiolitis interstitial pneumonitis (BIP), an unclassified and newly described interstitial pneumonia, has a combined feature of prominent bronchiolitis, interstitial inflammation, and fibrosis. It is distinct from bronchiolitis obliterans or bronchiolitis obliterans organizing pneumonia (BOOP). BIP has a better prognosis than common cases of interstitial pneumonia. However, BIP has a poorer prognosis than BOOP. BIP's response to corticosteroids is not as successful as BOOP's response to this treatment. We encountered the case of a 31-year-old woman with BIP with an initial presentation of dyspnea and a cough that had lasted for 3 months. The patient's chest CT scan demonstrated patchy ground glass opacities and multiple ill-defined centrilobular nodules in both lungs, suggesting military tuberculosis or nontuberculous mycobacterial infection. A video-assisted thoracoscopic lung biopsy resulted in the diagnosis of BIP. Clinical symptoms, pulmonary lesions, and pulmonary function tests were improved after oral glucocorticoid therapy.