A 59–year–old male with a history of asthma presented to our emergency department with severe wheezing associated with shortness of breath. His asthma had been stable, requiring albuterol inhalation one to two times per month. He had no history of being intubated due to asthma exacerbation. Five days prior to presentation, he experienced flu–like symptoms, including fever, chills and nonproductive cough. In the emergency room, he was in a severe respiratory distress and he underwent emergent intubation. His vital signs were T 97.5 °F, BP 168/91 mmHg, HR 132 beats/min, RR 30 breaths/min, and SpO2 88% on a 100% non–rebreather mask. His heart sounds were rapid and lungs revealed scattered wheezing. Arterial blood gas analysis showed pH of 6.91, PO2 of 83 mmHg, PCO2 of 166.9 mmHg, bicarbonate of 32.9 mEq/L, and O2 saturation of 88.8%. Laboratory studies disclosed WBC 14.500/mL with 55% neutrophils, HGB 14.9 g/dL, PLT 378 K/mL, and his chemistry panel was unremarkable. His chest X–ray showed no effusion or consolidation. He was admitted in ICU and methylpredonisone 80mg was given intravenously every 6 hours for 3 days without improvement. Mycoplasma IgG/IgM, Chlamydia IgG/IgM, Legionella urine antigen and rapid test for influenza antigen were negative. Rapid antigen for Respiratory Syncytial Virus (RSV) as well as nasal swabs for RSV antigen showed positive results. His high dose prednisone therapy was discontinued. His respiratory status gradually improved with ventilator management and he was extubated on day 5 after admission.
RSV is the most common cause of acute lower respiratory infection in children. However, RSV infection is relatively rare in healthy adults and its incidence and impact is not well recognized. RSV can cause significant morbidity and mortality among elderly people, especially persons with chronic underlying diseases and immunocompromised hosts. Several studies and outbreak reports of RSV in long term care facilities demonstrated significant number of incidence (3–40%), morbidity and mortality (range: 0–53%). Also, a number of studies indicated that RSV is one of the most common precipitants of infection–induced wheezing. In our case, wheezing was probably due to bronchiolitis caused by RSV, considering his well controlled asthma and wheezing refractory to high dose steroid therapy. RSV bronchiolitis mimicking asthma exacerbation posed us a significant diagnostic challenge. RSV bronchiolitis should always be considered as a cause of wheezing to avoid unnecessary treatment such as high dose steroid or antibiotics therapy.
RSV is a common pathogen that can cause wheezing. However, RSV infection in adults and the elderly is under–recognized. It can cause significant morbidity and mortality in the elderly and immunocompromized patients. RSV bronchiolitis can pose a diagnostic challenge among hospitalists due to lack of familiarity. RSV should always be considered as a cause of respiratory disease as well as wheezing in adults and the elderly.