To investigate the clinical features and prognosis of undifferentiated connective tissue disease. (UCTD) METHODS: 1105 connective tissue disease (CTD) patients, including 751 cases of systemic lupus erythrematosus (SLE), 63 cases of systemic sclerosis (SSc), 103 cases of polymyositis/dermatomyositis (PM/DM), 159 cases of primary Sjögren's syndrome (pSS), and 29 cases of overlap syndrome (29), were randomly selected. The clinical data of these patients were analyzed to identify those who displayed the manifestations of UCTD as the onset manifestations so as to summarize the clinical manifestation, immunological parameters, and long term development of UCTD.
These 145 patients with UCTD developed SLE, SSc, SS, PM/DM, or overlap syndrome within two to five years. The patients with arthritis and arthralgia often developed into SLE. Raynaud's syndrome was often related to SSc. The patients with rash or face edema were more likely turned out to be PM/DM patients. The patients with dry eyes or dry mouth often developed into pSS patients.
UCTD can develop into various autoimmune diseases, such as SLE, SSc, pSS or PM/DM. Some clinical features of onset are related with the outcome.