Editorial [ UCTD and Unfinished Business ]

In this issue of Current Rheumaology Reviews, Farhey and Hess review the concepts of mixed connective tissue disease (MCTD) and undifferentiated connective tissue disease (UCTD) [1]. It is now widely agreed upon the MCTD has a reproducible set of serologic findings, clinical manifestations and statistically validated defined criteria. Once thought to be a benign process, nearly 20% develop pulmonary hypertension, which is its major cause of death. The review succinctly summarizes the literature with regards to management and prognosis. Less well understood is UCTD. In 1982, an American College of Rheumatology endorsed collaborative effort evolved a working definition for UCTD [2]. It included isolated Raynaud's phenomenon, unexplained polyarthritis, or isolated keratoconjunctivitis sicca. Those who had one of these 3 manifestations also had to have at least three additional findings among the following: Raynaud's, polyarthritis, sicca symptoms, myalgias, rash, pleurisy, pericarditis, central nervous symptoms, pulmonary symptoms, peripheral neuropathy, false-positive test for syphilis, and elevated sedimentation rate. Over 20 years of observations, the outcomes of 410 patients originally enrolled were consistent with one third having no disorder at follow up, one third still manifesting UCTD, and one third evolving accepted criteria for rheumatoid arthritis, primary Sjogren's, scleroderma, systemic lupus erythematosus or inflammatory myositis [3]. UCTD is the "tip of the iceberg". It does not overlap with MCTD and is different from early inflammatory arthritis that will declare itself as rheumatoid arthritis or another process within 12 months. The number of UCTD patients in my practice exceeds the number with scleroderma and polymyositis that I see, and other than the United States and a couple of European cohorts, very little is known about these individuals. We tend to manage UCTD patients with nonsteroidal anti-inflammatory agents, hydroxychloroquine, methotrexate and occasional corticosteroids. Since the disorder is rarely, if ever, organ threatening, aggressive management is uncommon. However, there are no controlled studies relating to the treatment or clinical outcomes of the disorder. The prevalence of UCTD is not known, but it is probably the second or third most common autoimmune disorder seen in clinical practice. This editorial makes the following suggestions: 1. A committee should be constituted to derive an updated consensus definition for UCTD and work to have it validated. 2. Patients with UCTD should be considered a distinct entity in existing rheumatic disease cohorts and thus be available for observational studies and clinical trials. REFERENCES [1] Farhey Y, Hess EV. Mixed connective tissue disease (MCTD) and undifferentiated conncective tissue disease (ICTD), Curr Rheumatol Rev 2006; 2: 261-267. [2] Alarcon GS, Williams GV, Singer JV, et al. Early undifferentiated connective tissue disease. 1. Early clinical manifestations in a large cohort of patients with undifferentiated connective tissue disease compared with cohorts of well established connective tissue disease, J Rheumatol 1991; 18: 1332-1339. [3] Williams HG, Alarcon GS, Joks R, et al. Early undifferentiated connective tissue disease (CTD): VI: An inception cohort after 10 years: disease remissions and changes in diagnoses in well established and undifferentiated CTD, J Rheumatol 1999; 26: 816-825.