An unusual case of undifferentiated connective tissue disease presenting as cardiac tamponade.

Cardiac tamponade as an initial manifestation of undifferentiated connective tissue diseases (UCTD) is extremely rare, with only one case reported in literature thus far. We describe here, a case of a middle-aged man who presented with symptoms of fatigue, exertional dyspnea and orthopnea. His physical exam was significant for anasarca, elevated JVP and pulsus paradoxus. Chest X-ray showed pleural effusions and cardiomegaly, electrocardiogram revealed electrical alternans and a transthoracic echocardiogram demonstrated massive pericardial effusion with hemodynamic compromise. There was clear evidence of tamponade on right heart catheterization. All common causes of pericardial effusion were assiduously excluded before working up the patient for connective tissue disorders, which revealed a high antinuclear antibody titer (1:160), grossly elevated SSA, SSB antibodies and increased C-reactive protein levels (13.04 mg/dl). Patient had no signs or symptoms suggestive of systemic sclerosis (xerophthalmia or xerostomia) and did not meet criteria for any other known connective tissue diseases. He was therefore diagnosed with UCTD, and successfully treated with colchicine after emergency pericardiocentesis. This case presents UCTD as a rare cause of cardiac tamponade and large pericardial effusions and suggests that colchicine can be used to treat UCTD-associated effusions. These patients once diagnosed, are at risk of developing known connective tissue diseases within 5 years of disease onset and should be followed up in clinic periodically.