Disease evolution in a long-term follow-up of 104 undifferentiated connective tissue disease patients

Comment on: Disease evolution in a long-term follow-up of 104 undifferentiated connective tissue disease patients

“…Therefore, it is important to know what clinical and/or laboratory characteristics of UCTD patients might suggest their evolution into definite CTD. We read with great interest the study by Radin et al on the disease evolution of UCTD (1). It is surprising that 44 patients (44%) developed novel clinical and/or laboratory features and that 21 patients (21%) evolved into definite CTD patients in the long-term follow-up of the study (1).…”

“…We read with great interest the study by Radin et al on the disease evolution of UCTD (1). It is surprising that 44 patients (44%) developed novel clinical and/or laboratory features and that 21 patients (21%) evolved into definite CTD patients in the long-term follow-up of the study (1). However, we have several questions on their study.…”

“…However, it was not detailed what definite CTDs were developed by the UCTD patients with anti-Ro/SSA and/or anti-RNP antibodies (1). Moreover, it was not mentioned whether the anti-Ro/SSA antibodies were anti-Ro60 antibodies and/ or anti-Ro52 antibodies (1). Anti-Ro60 antibodies are found mainly in sera of patients with SLE and Sjögren's syndrome, whereas anti-Ro52 antibodies are found in several autoimmune entities and conditions (2).…”

“…1) (7). Radin et al (1) did not mention pulmonary hypertension by echocardiography and/or right heart catheterisation. UCTD has been defined as a condition characterised by the presence of symptoms and laboratory find-ings of CTD, but not fulfilling the existing classification criteria for any definite CTD (8).…”

“…UCTD has been defined as a condition characterised by the presence of symptoms and laboratory find-ings of CTD, but not fulfilling the existing classification criteria for any definite CTD (8). Thus, the patients diagnosed with anti-RNP antibody-positive UCTD in the study by Radin et al (1) might have been diagnosed with MCTD from the beginning of follow-up under the Japanese diagnostic criteria for MCTD. An international validation study on new MCTD criteria is called for (7).…”