The primary objective of the study is to describe the different phenotyping of pain in systemic scleroderma patients and perturbations of mechanisms of the pain.

As secondary objectives, the study aims to describe the importances of overall symptoms in alteration of quality of life and conserve the questions which will be associated in a unique questionnaire in order to evaluate the pain, the fatigue and the sleeping disorders in diffused systemic scleroderma patients.

This is a prospective, non-randomized, controlled study.

Beside the routine care, the patients will have only one visit in the study during which the informed consent will be signed, also the following will be performed: pain evaluation, blood sampling, questionnaires and Sudoscan, test QST.

100 patients will be enrolled in total with 50 in each group (scleroderma with pain vs. scleroderma without pain, 1:1 ratio), the duration of inclusion is estimated for 23 months.

2 centers will be involved in the enrollment of patients: rheumatology department and interne medicine department of Cochin hospital-APHP. One center will perform the evaluations of pain for all patients: center of pain of Cochin hospital - APHP.

Inclusion Criteria:

• Patients ≥ 18 years;
• Patients with diffused SSc according to ACR / EULAR Classification 2013 since at least 3 months;
• For group pain: pain intensity ≥4 of 11 points of scale (NRS);
• For group painless: pain intensity on the month before inclusion.

Exclusion Criteria:

• Patients unable to understand french language;
• Patients no-affiliated to the french social security scheme;
• Patients under the french AME scheme;
• Patients under guardianship;
• Pregnant and breastfeeding patients;
• Patients with thermoalgesic neuropathy;
• Articular pain from degenerative diseases (known osteoarthritis);
• Patients under antidepressant;
• Temporary discontinuation of analgesics which are not well tolerated.