DIGITAL LESIONS (DL) IN SYSTEMIC SCLEROSIS (SSC): EVIDENCE FOR A NEW CLASSIFICATION OF DIGITAL ULCERS (DU)

Background: In SSc digital lesions (DL) are linked to microvascular sufferance, frequently leading to DU, gangrene and amputation. Objectives: The lack of classification in SSc has prompted us to evaluate the morphology and characteristics of DL to provide a new classification that may correctly define DL and DU. Methods: 100 SSc patients were consecutively followed up in 4 years. DL were observed and methodologically classified. In every identified DU subset, pain, stage and the single characteristics of DU were identified. Results: In 4 years, 1614 DL were observed and classified in Digital Pitting Scar - 712 lesions (44,1%), Digital Ulcer - 792 lesions (49,1%), and Calcinosis 110 (6,8%). DU were classified in subsets as follows: DU developed on Digital Pitting Scar, found in 1,41% of DPS, were all superficial, characterized by inflammation and edema of perilesional skin and by spontaneous mild or moderate pain; DU characterised by Loss of Tissue characterised by irregular edges (80,3%), edema (56,44%), inflammation of perilesional skin (75%) and the stage was usually intermediate (59,85%) or deep (39,90%). Only in few cases, muscle or bone and tendons (1,77%) were exposed. DU, developed in 60% of preexisting calcinosis, were always deep with irregular edges and inflammation of perilesional skin and spontaneous severe pain (83,33%). Conclusion: DL are mainly represented by Digital pitting scars, DU and calcinosis. The patient follow up has allowed a morphological DU classification with the definition of the main DU characteristics, of DU pain and staging. This classification may be helpful in practice and in future RCTs for a precise identification of those DU that are to be included or excluded in specific therapeutic studies.