CASE PRESENTATION Initial Presentation and History

woman presented to the emergency department with dry cough and dyspnea on exertion. Three months prior to this presentation, the patient presented to her primary care physician for a flu-like illness with recurring episodes of fatigue and myalgias without fever, weight loss, or night sweats. Initial chest radiograph ordered by the primary care physician re-vealed bilateral lower lobe infiltrates. The patient was diagnosed with community-acquired pneumonia and was given multiple courses of antibiotics, which did not improve her symptoms. Repeated chest radiographs over 3 months demonstrated that the bilateral lower lobe infiltrates had not resolved. The patient’s dyspnea progressively worsened over 6 weeks following a course of oral antibiotics. Patient Evaluation In the emergency department, physical examina-tion revealed a temperature of 97.9°F (36.6°C), respi-ratory rate of 18 breaths/min, blood pressure of 165/ 85 mm Hg, heart rate of 92 bpm, and oxygen satura-tion of 95 % without supplemental oxygen. No lymph-adenopathy was found. Chest auscultation revealed bilateral crackles. Abdominal examination was normal, and there was no lower extremity edema. Results of serum chemistry studies and the white blood cell count were normal. The patient was admitted to the hospital for further work-up. Blood culture and sputum culture were negative. A chest radiograph showed bilateral infiltrates. Com-puted tomography (CT) of the chest showed bilateral patchy air-space consolidation with air bronchograms predominantly in the lower lung lobes and without me-diastinal lymphadenopathy (Figure 1). All results from serologic evaluation for vasculitis and immunologic diseases were negative. Analysis of bronchial lavage specimens showed no bacterial or viral infection and no malignant cells. Bronchoscopy with transbronchial lung biopsy was performed; evaluation of the speci-mens revealed intra-alveolar plugs of granulation tissue composed of inflammatory cells and myxoid connective tissue (Figure 2). Viral inclusions were absent. Cultures for acid-fast bacilli, viruses, and fungi were negative