PO:24:065 | Nailfold capillaroscopic in primary Sjögren's syndrome, clinical and serological correlations; a preliminary report from a reference center

Caterina Vacchi¹, Filippo Santoro¹, Maria Grazia Malandra¹, Giulia Cassone¹, Alessandra Carobbio², Martina Orlandi¹, Dilia Giuggioli¹ | ¹Reumatologia Modena, Italy; ²Statistica Medica Modena, Italy

Background. Nailfold capillaroscopy (NC) is an imaging method to assess microcirculation and examine microvascular abnormalities in rheumatic diseases. Its role is well-defined for Raynaud’s phenomenon (RP), where NC may discern a primary RP (pRP) from a secondary due to systemic sclerosis. In Primary Sjögren’s syndrome (pSS) RP may be present in 10–30% of patients, reflecting a possible underlying microvasculopathy.

Objectives. To describe NC abnormalities in pSS patients vs pRP patients. - Among pSS patients, to correlate NC abnormalities with clinical-serologic features.

Materials and Methods. All the consecutive pSS patients (according 2016 ACR/EULAR classification criteria, positive MSGB, excluded overlap syndromes) and pRP controls were evaluated by NC in a 4-months period (Jan/01/2025–May/01/2025). Main clinical and serologic features in pSS patients were collected(table2). NC was performed according to EULAR study group on microcirculation in rheumatic diseases(1). A qualitative assessment (scleroderma pattern or not) and a quantitative assessment were performed. From the latter point of view, the following capillary characteristics were evaluated when assessing an image: capillary density, morphology (crossing/tortuous shape or neoangiogenic features), presence/absence of ectasias, giant capillaries and haemorrhages. The presence of multiple giant capillaries or the combination of abnormal shapes with a lowered number of capillaries points to a “scleroderma - SSc - pattern”.

Results. NC was performed in 71 pSS patients (F/M 69/2; median age: 65.0 IQR:52.0-72.0) and 70 pRP controls (F/M 52/18; median age: 51.5 IQR:33.0-61.0). Comparing the groups, no differences were found in terms of capillary density, ectasias/giant capillaries. pSS patients presented more frequently haemorrhages, crossing shape capillaries and neoangiogenic features than pRP [Table 1]. RP was present in 53,7% of cases, 11 patients (16,9%) presented CENP-B, 51 SSA-Ro and 34 SSB-La. As shown in Table 2, in pSS subjects, giant capillaries was strongly associated to RP, with a trend toward significance for CENP-B antibodies. Also, neoangiogenic features were more likely to be present in CENP-B patients. Ssc pattern was present in 6 pSS patients, with statistical association, as expected (p=0,028). RP was reported by all subjects, one patient presented CENP-B, while 5 subjects presented SSA-Ro/SSB-La. As expected, RP was strongly associated with CENP -B (p< 0,001), with all CENP-B patients presenting RP, RP was also associated to SSc pattern, even in absence of statistical significance (p = 0,055). We failed in finding an association between SSc pattern and CENP-B.

Conclusions. The role of NC in pSS has been investigated in only a few studies. There is no evidence that patients with pSS have distinct NC characteristics compared to pRP(2). The prevalence of NC alterations may differ depending on the specific subset of pSS patients. Comparing NC features in pSS patients and overlap conditions could be a fascinating field of study in the future.