Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia with airflow obstruction is a rare form of lung injury. All of the reported cases have been diagnosed by surgical lung biopsy. Only three of the reported cases presented with diffuse interstitial lung opacities on HRCT scans. We report three additional cases of this entity. All of the patients were female and presented with mild-to-moderate airflow obstruction. In the first case, transbronchial biopsy and imaging data were sufficient to make the diagnosis. Although the HRCT scans of all three cases revealed a mosaic pattern, that of the third patient also revealed diffuse interstitial infiltrate. In extremely rare cases, HRCT findings can simulate those seen in other interstitial lung diseases.

Keywords: Neuroendocrine cells; Carcinoid tumor; Bronchiolitis obliterans.