Lung involvement in “stable” undifferentiated connective tissue diseases: a rheumatology perspective

Undifferentiated Connective Tissue Disease With Isolated Diaphragmatic Dysfunction

Undifferentiated connective tissue disease (UCTD) is a rare autoimmune disorder with a prevalence of about two people per 100,000 people per year. Patients present with the features of different connective tissue diseases, including systemic lupus erythematosus, systemic sclerosis, polymyositis, and rheumatoid arthritis, with some positivity in serological markers that is insufficient to fulfill the criteria of any recognized connective tissue disorder. Pulmonary involvement is usually subacute and pleomorphic, which can cause a delay in the diagnosis. A few cases of UCTD involving an isolated diaphragm in the pulmonary system have been reported. We report a case of a 48-year-old female who initially presented with various nonspecific symptoms, including fatigue, polyarthralgia, dry mouth, and Raynaud's phenomenon. Subsequently, she developed significant dyspnea and orthopnea. Laboratory, immunology, and imaging workups were negative for any specific diagnosis. Pulmonary function tests showed severely low maximum inspiratory pressure (MEP) and maximum expiratory pressure, suggesting diaphragmatic dysfunction. A diagnosis of UCTD was considered, and she was treated with hydroxychloroquine and intravenous immunoglobulin (IVIG), which improved her respiratory symptoms and pulmonary function tests.

Undifferentiated connective tissue disease at risk for systemic sclerosis: Which patients might be labeled prescleroderma?

Undifferentiated Connective Tissue Disease at risk for Systemic Sclerosis (UCTD-risk-SSc), otherwise referred to as very early-early SSc (very early-early diagnosis of systemic sclerosis VEDOSS), is a condition characterized by Raynaud's phenomenon (RP) and either SSc serum marker autoantibodies or a capillaroscopic scleroderma pattern or both, but without satisfying classification criteria for SSc neither features consistent with SSc sine scleroderma. Approximately half the UCTD-risk-SSc patients develop definite SSc over 5-10 years of follow-up. Identifying patients who will undergo such evolution is an unmet need. Predicting at onset which patients with RP are going to develop SSc over time has long been a research objective and still is an unaccomplished task. The present review is devoted to the critical analysis of the nosographic boundaries of the condition and of items predictive of evolution including serological, capillaroscopic and circulating markers. A weighted score, based on serum antinuclear antibody titre, serum marker antibodies positivity and avascular areas has been developed and may identify in the meanwhile patients to be labeled prescleroderma i.e. those probably developing SSc over time. Future research should be directed to investigate unexplored features, validate and improve the performance of the score and highlight the involved pathways to be contrasted in order to identify a targeted therapy hampering the development of overt SSc.