NOD2 and Blau syndrome: Blau’s syndrome, however, lacks the pulmonary features which are present in the majority of paediatric sarcoidosis cases, and has an earlier median age at uveitis onset (5 years, with median onset of arthritis at 2 years old).76 Multiple genotypes for Blau syndrome exist, and it is possible that the many different mutations of NOD2 confer different risks of ocular involvement.