Cunninghamella bertholletiae pneumonia showing a reversed halo sign on chest computed tomography scan following cord blood transplantation.

This is the first reported case of a patient who developed fungal pneumonia caused by Cunninghamella bertholletiae (= C. elegans) following cord blood transplantation and who showed a reversed halo sign on a chest computed tomography scan (CT). In addition, the pathological findings related to the reversed halo sign are described in detail for the first time. The patient died due to respiratory failure and at autopsy, a consolidation corresponding to the reversed halo sign noted on CT was found histologically to be composed of a central infarct with some retained air spaces surrounded by a peripheral ring-like hemorrhagic band. Pulmonary vasculatures were occluded by thrombi containing numerous Zygomycetes hyphae within the central infarct and less frequently along the surrounding hemorrhagic band. A reversed halo sign may be an early marker to initiate preemptive therapy against Zygomycetes including C. bertholletiae.