The patient known case of MCTD, SLE, Sjogren syndrome.

This case demonstrates interval degeneration of multiple pre-existing ground glass nodules into emphysematous cysts with millimeter thick walls.  Interval growth of the pre-existing bilateral pulmonary cysts.  Interval development of new bilateral scattered ground glass nodules and interval development of non-specific irregular solid subpleural nodule in the left lower lobe.  Grossly unchanged bilateral axillary and mediatinal lymphadenopathy.  Among the differential diagnostic considerations one should consider Wegener's granulomatosis and lymphocytic interstitial pneumonitis.  If the patient is immunocompromised, PCP and fungal pneumonia should be considered.  Finally, lymphoproliferative disorders and cystic metastases to the lung parenchyma should be excluded.