The frontal chest x-ray shows bilateral symmetrical air space opacities in the peripheries of the lung field, giving rise to a reverse bat-wing appearance.

The air space opacities in this patient with haemoptysis is due to pulmonary alveolar hemorrhage. After further investigations, the patient was diagnosed with cryoglobulinaemic vasculitis.

The causes of reverse bat-wing appearance on the chest x-ray can be due to

• Trauma: Pulmonary Contusion.
• Vascular: Pulmonary embolism.
• Eosinophilic pneumonia.
• Sarcoidosis
• Vasculitis
• Malignancy: Bronchoalveolar carcinoma

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