Diagnosis
The diagnosis is based on complaints, symptoms and organ involvement and on the presence of anti-U1RNP antibodies in high titre (concentration). It is the only connective tissue disease for which one specific type of antibody is necessary to make a diagnosis (at least in most centres). If the doctor suspects the diagnosis of MCTD, some additional tests like lung function tests, heart check-up, examination of the kidneys and blood pressure need to be carried out. In case of muscle complaints or nerve pains an electromyography is necessary. The results of these examinations may also contribute to a diagnosis.