Abstract
Diffuse idiopathic pulmonary neuroendocrine cell (DIPNECH syndrome) remains unfamiliar to most clinicians even though it was first described almost 30 years ago. Diagnosis is usually confirmed histopathologically after lung biopsy, but often, a diagnosis or suspected diagnosis can be made radiographically. In this paper, we present a case report of a 68-year-old female with shortness of breath and fleeting pulmonary nodules observed on chest CT scan. She was initially misdiagnosed with asthma based on an abnormal pulmonary function test which revealed an obstructive ventilatory defect. The classic radiographic findings of DIPNECH syndrome and the typical patient demographics that should arouse suspicion of a DIPNECH diagnosis were also illustrated. DIPNECH syndrome is a clinicopathological syndrome whereas focal NECH is a pathological diagnosis that is often made incidentally on histological examination and is encountered in a variety of settings, including in resected carcinoid tumors, in the context of reactive changes concomitant with infection, in metastatic cancer, radiation pneumonitis, intra-lobar sequestration, smokers, interstitial lung disease, and lung adenocarcinoma. There are no proven treatments for DIPNECH syndrome. In patients with obstructive ventilatory symptoms, bronchodilators with inhaled steroids are usually prescribed. Some severe cases may require parenteral steroids. Somatostatin analogs (SSA) have also been used in some cases with mixed results. Rapamycin has been used in several cases based on the purported activation of the mammalian target of rapamycin (mTOR) in DIPNECH. Some patients with large carcinoid tumors may benefit from resection.