CTLA4 and interstitial lung disease: In the patients with PID associated ILD, referring classification proposed by the International Union of Immunological Societies [11], auto-inflammatory disorders (including SAVI and COPA syndrome), diseases of immune dysregulation (including cytotoxic T-lymphocyte associated protein-4 (CTLA4) deficiency, autosomal dominant signal transducer and activator of transcription 3 (STAT3) mutation and autoimmune lymphoproliferative syndrome (ALPS)) and chronic granulomatous disease (CGD) were common.