Diagnosis re-evaluation showed anti-AQP4 antibodies, indicating NMOSD, and determined that the patient met the American–European Consensus Group Criteria (US-EU criteria) for Sjögren’s syndrome, based on anti-SSA antibody detection, a positive Schirmer’s test, and a lip biopsy with focal lymphocytic sialoadenitis. This evidence concerns the gene AQP4 and Sjogren syndrome.