Interstitial lung disease has rarely been reported in Blau syndrome, a familial granulomatous disorder caused by mutations in the CARD15/NOD2 gene, encoding the cytosolic NOD2 protein (nucleotide-binding oligomerization domain protein 2), one of the key molecules in the regulation of innate immunity: the disease starts in the first years of life with articular, cutaneous, and ocular non-caseating granulomatous inflammation [41]. This evidence concerns the gene NOD2 and Blau syndrome.