Medical image of the week: the atoll sign in cryptogenic organizing pneumonia

Abstract

No abstract available. Article truncated at 150 words. A 54-year-old woman presented to the emergency department with cough and worsening shortness of breath. Her cough began approximately 1 month prior to presentation, at which time she was diagnosed with pneumonia by her primary care physician based on a chest X-ray at an outside institution. She tried and failed courses of azithromycin, doxycycline, and levofloxacin. The patient had an oxygen saturation of 55% and hyperpyrexia to 101.7 F in the emergency department. An initial chest X-ray was suggestive of moderate multifocal pneumonia with pleural effusion (Figure 1). Subsequent chest computed tomography (CT; Figure 2) revealed findings consistent with cryptogenic organizing pneumonia (COP) including multiple upper lobe atoll signs. Infectious and autoimmune workups were negative and the patient experienced a rapid recovery with pulse steroids, providing further evidence for the diagnosis of COP. CT is the best imaging modality for evaluation of potential COP. Features include consolidations and nodules, bronchial …

Keywords

• atoll sign
• cryptogenic organizing pneumonia
• COP
• chest x-ray
• CT scan
• reverse halo sign
• specificity
• sensitivity
• ground glass opacity
• consolidation