Centrilobular Ground-Glass Nodules

• Acute hypersensitivity pneumonitis: Ground-glass centrilobular nodules and mosaic attenuation. Lower lobes. Pleural surfaces commonly spared or less involved.
• Respiratory bronchiolitis-interstitial lung disease: Smokers. More commonly in the upper lobes.
• Desquamative interstitial pneumonia: Peripheral predominance
• Atypical infection: Pneumocystis jiroveci pneumonia, Mycoplasma, viral (e.g., cytomegalovirus)
• Collagen vascular disease: For example, Sjögren syndrome.

References

• Matsuyama N, Ashizawa K, Okimoto T, Kadota J, Amano H, Hayashi K. Pulmonary lesions associated with Sjögren's syndrome: radiographic and CT findings. Br J Radiol. 2003 Dec;76(912):880-4.
• Mueller-Mang C, Grosse C, Schmid K, Stiebellehner L, Bankier AA. What every radiologist should know about idiopathic interstitial pneumonias. Radiographics. 2007 May-Jun;27(3):595-615.