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A4149 - Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia (DIPNECH): A Case Report of a Rare Disease
Author Block: P. Pedro1, D. Canario1, M. Lopes1, A. Oliveira1, J. Soares1, C. Rodrigues2, J. R. Vieira1; 1Hospital Garcia de Orta, Almada, Portugal, 2Hospital Pulido Valente, Lisboa, Portugal.
According to the World Health Organization, the definition of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is purely histological. It consists of a primary neuroendocrine cell proliferation often accompanied by constrictive obliterative bronchiolitis, that is considered a pre-neoplastic lesion in the spectrum of pulmonary neuroendocrine tumours. It can be presented without any clinical or radiological features of airway disease; however, there’s a distinct patient subgroup who have chronic respiratory symptoms and mosaic attenuation with air trapping on chest imaging.
We present a case of DIPNECH and describe the approach to diagnosis of this condition.
A 39-year-old caucasian female, who has never smoked, was consulted in the respiratory department of our hospital because of a chronic dry cough with 16 year duration that in the last 6 months was more persistent and got associated with mild exertional dyspnoea and occasional wheezing. She was working in the recycling of electronic material, and had a past medical history of non-allergic rhinitis. A high-resolution computed tomography (HRCT) scan of the chest was performed, which showed multiple micronodular formations, bilateral and multilobar, uniform in size, non-calcified and centrilobular. Additionally, there was diffuse mosaic lung pattern with air trapping. The lung function tests presented an isolated increase in residual volume. A flexible bronchoscopy with alveolar bronchial lavage was unrevealing. The patient did a second HRCT that revealed stability of the alterations already described. We decided to perform rigid bronchoscopy with cryobiopsy which showed pulmonary parenchyma with nonspecific inflammatory infiltrate. Our patient underwent wedge resection of segment 6 of the right lung and middle lobe with pathology revealing foci of neuroendocrine cells hyperplasia and tumourlets, adjacent to the bronchiolar wall, measuring 0.3 cm at maximum, and associated with constrictive bronchiolitis, being suggestive of DIPNECH. No mitosis or necrosis were identified. Our multidisciplinary clinical team proposed to perform chromogranin A serum dosing and combined positron emission tomography and computed tomography (PET/CT) with 68Ga-DOTA-NOC to possibly detect a neuroendocrine
tumour, whose results we will have briefly. Currently, the patient maintains persistent cough but shows improvement with inhaled corticosteroid therapy.
The aim of this case report is to highlight this rare, but potentially progressive condition. There have now been more than 200 cases of DIPNECH described in the form of case reports or small case series, but is possible that still is an under-diagnosed pulmonary condition because it can frequently be asymptomatic. There’s still no evidence-based management guidelines for DIPNECH.