Résumé
•Cutaneous involvement is common during primary Sjögren syndrome (pSS), but prevalence and characteristics are difficult to establish.•The most common cutaneous involvement of pSS is skin dryness (evaluated by VAS).•Other dermatological signs of pSS are rare but associated with ESSDAI activity in other domains.
To determine the prevalence and significance of dermatological disorders in primary Sjögren syndrome (pSS).
We used 2 pSS French cohorts (ASSESS, in which prevalence of skin disorders in 395 patients was evaluated; and diapSS, in which 76 on 139 pSS patients had an examination by a dermatologist) and baseline data of the TEARS randomized trial (110 patients with recent or active pSS treated with rituximab or placebo and evaluated for skin dryness using a visual analogue scale (VAS) out of 100).
Skin manifestations included in the EULAR Sjögren syndrome disease activity index (ESSDAI) were rare in the ASSESS cohort (n=16/395, 4.1%, mainly purpuras; only 3 had high activity), but they were associated with activity in the other ESSDAI domains (peripheral neurological (P<0.001), muscular (P<0.01), haematological (P<0.05), biological (P<0.05), history of arthritis (P<0.01), splenomegaly (P<0.05) and higher gamma globulin levels (P<0.01)). In the diapSS cohort, compared to pSS patients not receiving a dermatological consultation, the pSS patients who had a dermatological consultation had significantly more dermatological involvement outside the ESSDAI score [38.2% (29/76) versus 15.9% (10/63); P<0.01]. The TEARS study showed a high prevalence of cutaneous dryness (VAS>50; 48.2%) and found that patients with dry skin had higher VAS pain (P<0.01) and drought (P<0.01) scores.
ESSDAI skin activity is rare and associated with hypergammaglobulinemia and ESSDAI activity. Systematic dermatological examination is informative for non-specific lesions. The most common skin disorder is skin dryness, which is associated with a higher pain and overall subjective dryness.