ANALYSIS OF A MONOCENTRIC COHORT OF IgG4-RELATED DISEASE PATIENTS: GREATER REDUCTION OF THE RESPONDER INDEX IN PHARMACOLOGICALLY-TREATED PATIENTS AS COMPARED TO UNTREATED ONES

Background: IgG4-related disease (IgG4-RD) is a systemic disease characterized by lymphoplasmocellular infiltration and storiform fibrosis. Pancreas, biliary tract, lacrimal and salivary glands, lymph nodes and retroperitoneum are frequently involved, although the clinical presentation may vary [1]. Objectives: The aim of this study is to retrospectively describe the clinical manifestations of a monocentric cohort of patients with IgG4-RD and analyze their clinical course by applying the validated IgG4-Related Disease Responder Index (RI) [2]. Methods: We enrolled 22 IgG4-RD patients classified with 2011 diagnostic criteria [3] and/or 2019 classification criteria [4]. Results: 22 IgG4-RD patients (M/F=3.4/1), mostly Caucasian (91%), were diagnosed at a mean age of 59 years (44-74) with a median IgG4 concentration at diagnosis of 239 mg/dl (IQR 106-391 mg/dL). 14/22 (64%) patients fulfilled the 2011 classification criteria, while 8/22 (36%) were classified as possible (2), probable (5) or definitive (1) according to the diagnostic criteria of 2011. Organ involvement at diagnosis (T0) is described in Table 1 . The organs most involved were lymph nodes, salivary glands and retroperitoneum. Patients were followed for a median of 49 months (IQR 16-88). Three patients were lost to follow-up. One patient died for pneumonia 96 months after diagnosis. During the follow-up 5 (23%) patients didn’t receive specific treatment, 1 (5%) was treated surgically, 6 (27%) with steroid only, 10 (45%) with steroid and immunosuppressants (with methotrexate and/or rituximab, tocilizumab, mycophenolate, cyclosporine, hydroxychloroquine, azathioprine) and/or surgical resection. A statistically significant reduction in RI between T0 and last follow-up (TLF) was observed in all the patients [from 6 (3-6) to 3 (1-4) p=0.010]. A significant reduction was also observed in the group of pharmacologically treated patients [from 6 (3-6) to 3 (1-4) p=0.035] but not in the group of patients without drug treatment (p = 0.174). Table 1. Organ involvement at diagnosis Organ involvement T0 N. Patients (% ) Pancreas 2 (9) Lymph nodes 14 (64) Salivary glands 13 (59) Lungs 1 (5) Aorta and large blood vessels 4 (18) Retroperitoneum, mediastinum, mesentery 6 (27) Bile duct and liver 3 (14) Kidneys 2 (9) Pachymeninges 1 (5) Orbits and lacrimal glands 3 (14) Paranasal sinuses and / or nasal mucosa 5 (23) Conclusion: In our cohort, patients were predominantly male with mean age at diagnosis of 59 years, consistent with literature data [1]. A statistically significant reduction in disease activity defined by reduction of RI was observed in patients who received immunosuppressive therapy. No significant reduction was observed in patients not pharmacologically treated. REFERENCES: [1]Dai Inoue et al. Medicine, 2015 [2]Carruthers M.N. et al. Int J Rheumatol, 2012 [3]Umehara H. et al. Mod Rheumatol, 2012 [4]Wallace Z.S. et al. Ann Rheum Dis, 2020 Disclosure of Interests: None declared Citation: , volume 81, supplement 1, year 2022, page 1761Session: Other orphan diseases (Publication Only)