It's Not the Lung! When a Neuromuscular Disease Presented as Recurrent Episodes of Shortness of Breath

Abstract

SESSION TITLE: Pulmonary Manifestations of Systemic Disease 2 SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: Recurrent episodes of shortness of breath and consequences of respiratory failure despite treatment requires reconsideration as such presentations may be due to a neuromuscular disease. CASE PRESENTATION: A 66yo male with a past medical history of hypertension and diastolic heart failure with EF 55% presents with progressively worsening dyspnea on exertion and multiple hospitalizations for hypoxic respiratory failure. CT chest revealed nonspecific bibasilar consolidations consistent with either atelectasis, aspiration, or pneumonia. Lung function demonstrated a mild restrictive defect, no obstruction, normal diffusion capacity, and no bronchodilator response. Patient improved with a trial of steroids but his clinical status continued to decline. Further history revealed loss of energy, generalized muscle weakness, joint pain, dysphagia with liquids but not solids, orthopnea, and dyspnea resulting in significant decrease in functional capacity to the point he was unable to use a sweeper around his house. Physical exam revealed central muscle wasting. Patient was urgently referred to Neurology and a motor nerve conduction study was obtained due to suspicion of a neuromuscular disorder. EMG of the upper and lower extremities showed abnormal activity and chronic neurogenic changes in multiple myotomes with decreased recruitment, consistent with an acute on chronic denervation process. After clinical evaluation, patient was formally diagnosed with ALS by Neurology. DISCUSSION: Amyotrophic lateral sclerosis (ALS) is a progressive neuromuscular degenerative disease of the upper and lower motor neurons resulting in muscle weakness, fasciculations, atrophy, and hyper-reflexia. Presentation is variable but is most often either bulbar, with complaints of dysphagia or dysarthria, or spinal, with complaints of muscle weakness and gait instability. However, dyspnea is seldom the primary symptom at presentation. Diagnosis is multifaceted and individualized, requiring a thorough history and physical examination. Advanced studies such as electromyography are utilized to demonstrate denervation in the limbs. When left untreated, major morbidity and mortality in the form of chronic aspiration, secretion retention, or pneumonia may result. Despite the lack of a cure, various medications and assist devices may prolong and improve the overall quality of life and mortality. CONCLUSIONS: Shortness of breath, though a common symptom for an underlying intrinsic lung disease such as pneumonia or COPD, may actually be the result of a neuromuscular disorder. A careful history and physical exam from a pulmonary standpoint is crucial to the aid in diagnosis. Reference #1: Pavletic, Adriana J., and Oleh Hnatiuk. “Puzzling Dyspnea Caused by Respiratory Muscle Weakness.” Journal of the American Board of Family Medicine: JABFM (2012); 25.3:396-397. Reference #2: Rowland, Lewis, and Shneider, Neil. “Amyotrophic Lateral Sclerosis”. The New England Journal of Medicine: NEJM (2001); 344:1688-1700. DISCLOSURE: The following authors have nothing to disclose: Meilin Young, Tiffany Dumont, Anil Singh No Product/Research Disclosure Information