Air Crescent Sign of Invasive Aspergillosis

Abstract

Pulmonary infection in immunocompromised patients is frequently difficult to diagnose. Therapy for more common pathogens differs greatly from that for infection with unusual opportunistic organisms. Neither of these infectious agents offers specific radiographic signs. A report is given on 4 patients with acute leukemia and invasive aspergillosis whose radiographs demonstrated a distinctive feature of 1 or more air crescents within an area of pulmonary infiltrate. Autopsy studies correlated radiographic changes with infection due to Aspergills sp. fungi. While the sign is not pathognomonic for Aspergills infection seen in a suitable host, invasive aspergillosis may be possible.