A 35 year-old black woman, previously healthy, who complained about chronic cough and shortness of breath was investigated after non-response of symptoms. Her chest X-ray and high resolution chest CT-scan were normal. She presented with abnormal spirometry, a mild restrictive disturbance. After a negative initial clinical investigation, an open lung biopsy was indicated. Multiple microscopic peribronchiolar tumorlets carcinoids - neuroendocrine cell hyperplasia was revealed. The authors emphasize the importance of an early diagnosis of this unusual entity and discuss its possible pathophysiological mechanisms.

Keywords: Lung diseases. Neuroendocrine cell. Bronchiolitis. Carcinoid. Tumorlets.