A 64-year-old man with a history of rheumatoid arthritis (RA) on treatment with methotrexate 22.5 mg weekly and adalimumab 40 mg biweekly, presented to the emergency department with complaints of cough, dyspnea, and fatigue. The patient reported cough and dyspnea over the eight weeks prior to presentation. He was treated as an outpatient for cough with a course of azithromycin, then doxycycline. However, he progressively worsened over the month prior to presentation as he began to experience dyspnea on exertion.Upon presentation, the patient was afebrile with stable vital signs. He had a normal cardiopulmonary examination. His complete blood count with differential, comprehensive metabolic panel, and brain natriuretic peptide were within normal limits. A chest x-ray revealed diffuse infiltrates. A computed tomography (CTA with/without contrast pulmonary embolism protocol) of the chest was negative for pulmonary embolism, but showed diffuse five lobe alveolar infiltrates with posterior predominance. No thoracic lymphadenopathy was noted (see image above).The patient was admitted for further work-up of progressive dyspnea with failed outpatient treatment and a bronchoscopy was performed the next day. On bronchoscopy, the pharynx,