TOPIC: Pulmonary Manifestations of Systemic Disease
      TYPE: Medical Student/Resident Case Reports
      INTRODUCTION: Chronic cough in adults is defined by cough lasting for at least eight weeks in duration. It remains one of the most common symptoms encountered in ambulatory care, largely attributed to Upper Airway Cough Syndrome (UACS), Asthma, Non-asthmatic Eosinophilic Bronchitis (NAEB), or Gastroesophageal Reflux Disease (GERD). Other less common etiologies shouldn't be overlooked, such as those disorders which stimulate cough receptors. These receptors are located throughout the body including the gastrointestinal tract; irritation of any of these can trigger the vagal-mediated afferent limb of the cough reflex arc. We present the case of a patient with gastric cancer with an initial complaint of three months of cough with associated dyspnea.
      CASE PRESENTATION: A 33-year-old male with a medical history of obstructive sleep apnea, prior tobacco use, and GERD presented with a three month history of dry cough, fatigue, and dyspnea. Previous primary care visits were conducted via telehealth amid the COVID-19 pandemic, where he was empirically treated with therapies for UACS, asthma, and reflux disease without improvement. His physical exam and chest radiograph were unremarkable. Pulmonary function tests were not obtained secondary to profound coughing with forced exhalation maneuvers. On further questioning, he endorsed early satiety, 10-pound weight loss, and a family history of stomach cancer. CT of the chest demonstrated questionable gastric thickening, retroperitoneal lymphadenopathy surrounding the mesenteric root, a nine millimeter lytic lucency along the right periphery of the 11th thoracic vertebral body, and subtle diffuse peripheral tree-in-bud pulmonary opacities. Bronchoscopy with lavage, brushings, and endobronchial biopsies were negative for infection, granulomas, or malignancy. Upper endoscopy revealed a laterally spreading lesion with central ulceration in the gastric cardia, with biopsy consistent with poorly differentiated gastric adenocarcinoma. Stage IV disease was confirmed by retroperitoneal lymph node sampling.
      DISCUSSION: Gastric cancer represents 1.4% of all new cancer cases annually in the U.S., most frequently in the sixth decade of life in those with multiple risk factors. Our patient presented nearly three decades earlier with a chronic cough which is exceedingly rare. Plausible risk factors for our patient include male sex, Hispanic ethnicity, obesity, prior tobacco use, and familial predisposition. Early symptoms are equivocal but usually include abdominal pain and weight loss. Respiratory symptoms generally portend late-stage metastasis to the lungs or pulmonary embolism, which our patient did not exhibit.
      CONCLUSIONS: While UACS, Asthma, NAEB, and GERD remain the most conceivable etiologies of chronic cough, fully investigating all red flag symptoms during patient encounters, with consideration of uncommon causes, endure as foundational tenets of chronic cough evaluation.
      REFERENCE #1: Irwin RS, French CL, Chang AB, Altman KW, CHEST Expert Cough Panel*. Classification of cough as a symptom in adults and management algorithms: chest guideline and expert panel report. Chest. 2018;153(1):196-209.
      REFERENCE #2: Kou A, Patel JK, Adetula I, Frunzi J. Gastric cancer presenting as persistent pneumonia: an unusual case report. Cureus. Published online March 21, 2021.
      REFERENCE #3: Polverino M, Polverino F, Fasolino M, Andò F, Alfieri A, De Blasio F. Anatomy and neuro-pathophysiology of the cough reflex arc. Multidiscip Respir Med. 2012;7(1):5.
      DISCLOSURES: No relevant relationships by Patrick Kicker, source=Web Response
      No relevant relationships by Ashley Soler Acevedo, source=Web Response