Asian Journal of Research in Nephrology

The Term undifferentiated connective tissue disease is used to define conditions characterised by the presence of signs and symptoms suggestive of a systemic autoimmune disease that does not satisfy the classification criteria for defined connective tissue diseases (CTD) such as systemic lupus erythematosus (SLE), Sjögren's syndrome (SS), rheumatoid arthritis (RA) and others.

The most characteristic symptoms of UCTD are represented by arthritis and arthralgias, Raynaud's phenomenon and leukopenia, while neurological and renal involvements are rare. Only one-third of the UCTDs evolve into full-blown CTD within the initial years (3-5). Here we are presenting a case of a 36-year female presenting with mono arthritis, proteinuria and severe anaemia that was diagnosed to have undifferentiated connective tissue disorder with tubercular mono arthritis of knee joint and membranous nephropathy. The patient was given anti-tubercular drugs, corticosteroids, hydroxychloroquine and PRBC transfusions. The patient was discharged and showed significant improvement on subsequent follow-ups. This case report provides insight into the various presentations of connective tissue disorder and also its multi-system involvement. Also sometimes these disorders cannot be classified by a criterion clinically or based on laboratory investigations into one single connective tissue disease.