Disease Profile and Achievement of Therapeutic Goals in a Modern, Nationwide Cohort of 923 Patients with Psoriatic Arthritis

Background

Psoriatic arthritis (PsA) is a heterogenous chronic inflammatory disease affecting skin, joints, entheses, and spine with various extra-musculoskeletal manifestations and comorbidities. The reported patient, disease and treatment characteristics in the modern therapeutic era are limited.

Methods

In this cross-sectional, multi-centre, nationwide study, we recorded the demographic, clinical, and therapeutic characteristics as well as the comorbidities of patients with PsA seen for 1 year (1/1/2022-31/12/2022).

Results

923 patients (55% females) with a median (IQR) age of 57 (48-65) years and a mean disease duration of 9.5 years were enrolled. Family history of psoriasis and PsA was noted in 28.3% and 6.3%, respectively. Most patients had limited psoriasis (BSA<3: 83%) while enthesitis, dactylitis, nail and axial involvement reported in 48.3%, 33.2%, 43% and 25.9% of patients, respectively. Regarding comorbidities, approximately half of patients had dyslipidaemia (42%) or hypertension (45.4%), 36.8% were obese and 17% had diabetes while 22.7% had a depressive disorder. Overall, 60.1% received biologics and among them more patients treated with anti-IL-17 or -12/23 agents were on monotherapy (64.2%) compared to those on TNFi monotherapy (49.4%, p=0.0001). The median PsA activity as assessed by the DAPSA score was 6 (IQR: 2.3 - 13.1) with 46% of patients reaching minimal disease activity status (MDA).

Conclusion

In this large, real life, modern cohort of patients with PsA with frequent comorbidities who were treated mainly with biologics, almost half achieved minimal disease activity. These results show the value of existing therapeutic approaches while at the same time highlight the existing unmet needs.

Occurrence and Antigenic Specificity of Perinuclear Anti-Neutrophil Cytoplasmic Antibodies (P-ANCA) in Systemic Autoimmune Diseases

Perinuclear anti-neutrophilic cytoplasmic antibodies (P-ANCA) recognize heterogeneous antigens, including myeloperoxidase (MPO), lactoferrin, elastase, cathepsin-G and bactericidal/permeability-increasing protein. Although P-ANCA have diagnostic utility in vasculitides, they may also be found in patients with various other systemic autoimmune rheumatic diseases (SARDs). Nevertheless, the clinical significance and the targets recognized by P-ANCA in such patients remain unclear. For this purpose, herein we investigated the occurrence of ANCA-related antigenic specificities in 82 P-ANCA-positive sera by multiplex ELISA, as well as their association with other autoantibodies. The P-ANCA-positive sera corresponded to patients with vasculitides (n = 24), systemic lupus erythematosus (n = 28), antiphospholipid syndrome (n = 5), Sjögren’s syndrome (n = 7), rheumatoid arthritis (n = 3), systemic scleroderma (n = 1), sarcoidosis (n = 1) and Hashimoto′s thyroiditis (n = 13). In most P-ANCA-positive patients studied (51/82, 62.3%), these autoantibodies occurred in high titers (>1:160). The analysis of P-ANCA-positive sera revealed reactivity to MPO in only 50% of patients with vasculitides, whereas it was infrequent in the other disease groups studied. Reactivity to other P-ANCA-related autoantigens was also rarely detected. Our findings support that high P-ANCA titers occur in SARD. The P-ANCA-positive staining pattern is associated with MPO specificity in vasculitides, while in other autoimmune diseases, it mostly involves unknown autoantigens.

POS0829 SPECIFICITY OF PANCA AUTOANTIBODIES IN AUTOIMMUNE DISEASES

Background:

The clinical significance of pANCA by indirect immunofluorescence is well-established. However, their clinical utility is sometimes hindered by the fact that pANCA are also detected in various autoimmune diseases. Myeloperoxidase (MPO) is considered as the major autoantigen recognized by pANCA in ANCA-associated vasculitides (AAV) and predominantly in microscopic polyangiitis (MPA). However, information regarding the targets of pANCA in other autoimmune diseases is still elusive.

Objectives:

To investigate the specific autoantigens recognized by pANCA in autoimmune diseases.

Methods:

Sera from all patients that were found positive for pANCA in the diagnostic laboratories of the Department of Pathophysiology, School of Medicine, National and Kapodistrian University of Athens and the Department of Immunology and Histocompatibility, Evangelismos General Hospital, Athens, Greece during the last two years were studied. The pANCA+ sera were evaluated for reactivity with the major antigens that are recognized by pANCA [MPO, lactoferrin, neutrophil elastase, cathepsin G and bactericidal/permeability increasing protein (BPI)] by a commercially available multiplex ELISA (ANCA profile ELISA, Euroimmun, Lubeck, Germany).

Results:

A total of 82 patients were included in the study. All patients had positive pANCA by indirect immunofluorescence with a title ranging from 1/160 to 1/640. According to respective classification criteria, 21 patients had systemic vasculitides (15 MPA, 1 granulomatosis with polyangiitis; GPA, 1 Behcet’s disease; BD, 1 aortitis, 2 Henoch-Schonlein purpura; HSP and 1 cryoglobulinemic vasculitis; CV), 29 had systemic lupus erythematosus (SLE), 6 antiphospholipid syndrome (APS), 8 Sjögren’s syndrome (SS), 2 rheumatoid arthritis (RA), 1 systemic scleroderma (SScl), 14 Hashimoto thyroiditis and 1 sarcoidosis. The specificities of pANCA in each entity are shown in the following table.

Autoimmune DiseasesAntigens recognized by pANCA+ seraMPOElastaseCathepsin GBPILactoferrinVasculitidesMPA66.7 (10/15)0 (0/15)0 (0/15)0 (0/15)0 (0/15)GPA100 (1/1)0 (0/1)0 (0/1)0 (0/1)0 (0/1)BD100 (1/1)0 (0/1)0 (0/1)0 (0/1)0 (0/1)Aortitis0 (0/1)0 (0/1)0 (0/1)0 (0/1)0 (0/1)HSP0 (0/2)0 (0/2)0 (0/2)0 (0/2)0 (0/2)CV0 (0/1)0 (0/1)0 (0/1)0(0/1)100 (1/1)SLE6.9 (2/29)0 (0/29)0 (0/29)0 (0/29)6.9 (2/29)APS16.6 (1/6)16.6 (1/6)0 (0/6)0 (0/6)0 (0/6)SS0 (0/8)12.5 (1/8)0 (0/8)12.5 (1/8)0 (0/8)RA50 (1/2)0 (0/2)0 (0/2)0 (0/2)0 (0/2)SScl100 (1/1)0 (0/1)0 (0/1)0 (0/1)0 (0/1)Hashimoto0 (0/14)0 (0/14)0 (0/14)0 (0/14)0 (0/14)Sarcoidosis0 (0/1)0 (0/1)0 (0/1)0 (0/1)0 (0/1)

Conclusion:

pANCA positive staining in AAVs is highly restricted to MPO specificity. On the contrary, pANCA staining pattern in other autoimmune diseases, involves unknown autoantigens that are under investigation in our laboratory.

Disclosure of Interests:

None declared