Jack: Nice article, echoing the others, and I agree with the vast majority of what you say. MCTD may have the most supporters in keeping in clinical practice. I actually don't mind MCTD when used correctly (limiting its use as initially described and in line with patient populations used for proposed classification criteria for MCTD), as studies do support certain characteristics for this group (eg the importance of screening regularly for PH, its most common cause of mortality). However, it is one of the most abused terms we have, as you allude to. It is amazing how many patients are labeled as MCTD who actually have UCTD or true overlap syndromes (even used in patients who are negative for RNP!) Then there is the camp of providers who call everything that walks who has a positive RNP antibody, "MCTD", though they don't come close to having its set of characteristics. I think MCTD still has its role, but boy is it misused ... nice job!