Cryptogenic organizing pneumonia

Case contributed by Mark Holland
Diagnosis probable


Presented to the GP with chronic cough. Patient had an incidental eosinophilia a year ago.

Patient Data

Age: 40 years
Gender: Female

Patchy air space opacities in bilateral upper zones.

Reversed halo pattern (atoll sign): there are round focal areas of ground-glass attenuation with surrounding crescent or ring-shaped consolidation.


Reversed halo shape of a daisy.

Case Discussion

Patient with organizing pneumonia shows a reversed halo pattern (atoll sign) where there are focal round areas of ground-glass attenuation with surrounding crescent or ring-shaped consolidation.

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