Undifferentiated connective tissue disease presenting with optic neuritis and concomitant axial spondyloarthritis: A rare case report.

Undifferentiated connective tissue disease (UCTD) represents a group of diseases which do not fulfill the criteria of rheumatologic diseases or may be considered as an early stage of any of these diseases. Axial spondyloarthritis (axSpA) is a disease accompanied by symptoms of inflammatory low back pain and peripheral symptoms, with more spine and sacroiliac joint involvement. In this report, we, for the first time, present a case of UCTD presenting with axSpA in whom the initial finding was optic neuritis, which is rarely seen in UCTD.