FRI0597 INVOLVEMENT OF TWO OR MORE SETS OF LACRIMAL GLANDS AND/OR MAJOR SALIVARY GLANDS IS RELATED TO GREATER SYSTEMIC DISEASE ACTIVITY IN IGG4-RELATED DACRYOADENITIS/SIALADENITIS
Authors: Masahiro Konishi, Ichiro Mizushima, Hajime Sanada, Kazuyuki Suzuki, Akari Takeji, Satoshi Hara, Kiyoaki Ito, Hiroshi Fujii, Kazunori Yamada, Mitsuhiro Kawano
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> IgG4-related dacryoadenitis/sialadenitis (IgG4-DS) is a major organ manifestation of IgG4-related disease (IgG4-RD) and is notable for its lack of a marked male predominance [1]. In IgG4-DS, involvement of two or more sets of lacrimal glands (LGs) and/or major salivary glands (MSGs) is regarded as a specific finding with diagnostic significance [2]. However, the influence of the presence of this finding on clinical features of IgG4-DS has not been well evaluated. <h3>Objectives</h3> This study aimed to clarify the influence of the involvement of ≥ 2 sets of LGs and/or MSGs on clinical features of IgG4-DS. <h3>Methods</h3> We retrospectively reviewed the medical records of 130 patients with IgG4-RD at a single center in Japan. Among them, 97 patients were diagnosed with IgG4-DS. We divided the 97 patients into Group A (n=44) with involvement of ≥ 2 sets of LGs and/or MSGs and Group B (n=53) with involvement of one set of LGs or MSGs or unilateral gland involvement. We compared the clinical features of Group A and B. Moreover, 33 IgG4-DS patients without extra-lacrimal/salivary gland lesions (DS-limited patients) were divided into Group a (n=14) and b (n=19) according to the presence/absence of the involvement of ≥ 2 sets of LGs and/or MSGs respectively, and their clinical features were also compared. <h3>Results</h3> The IgG4-DS patients comprised 60 men and 37 women (mean age 64.1 years). The mean follow-up period was 61.6 months, and the mean serum IgG4 level at diagnosis was 757 mg/dL. Group A had significantly more affected organs (3.5 ± 1.6 vs 2.7 ± 1.6, <i>P</i>=0.010), lower serum C3 and C4 levels (83.6 ± 29.5 vs 95.0 ± 25.2, <i>P</i>=0.018, and 16.5 ± 9.8 vs 21.4 ± 9.5, <i>P</i>=0.034, respectively), and a tendency to have higher serum IgG levels (2,509 ± 1,066 vs 2,165 ± 911, <i>P</i>=0.075) and IgG4-RD responder index (14.7 ± 6.7 vs 12.2 ± 6.5, <i>P</i>=0.050) than did Group B. In the 33 DS-limited patients, compared with Group b, Group a had no significant differences in clinical features including the proportion of patients with serum IgG4 elevation [≥ upper limit of normal (ULN), 85.7% vs 78.9%, <i>P</i>=1.000; ≥ 2× ULN, 64.3% vs 47.4%, <i>P</i>=0.482; ≥ 5× ULN, 28.6% vs 21.1%, <i>P</i>=0.695]. <h3>Conclusion</h3> Involvement of two or more sets of lacrimal glands and/or major salivary glands suggests greater systemic disease activity mainly due to involvement of more organs. <h3>References</h3> [1] Yamamoto M, et al. Everyday clinical practice in IgG4-related dacryoadenitis and/or sialadenitis: results from the SMART database. Mod Rheumatol. 2015Mar;25(2):199-204. [2] Masaki Y, et al. IgG4-related diseases including Mikulicz's disease and sclerosing pancreatitis: diagnostic insights. J Rheumatol. 2010Jul;37(7):1380-5. <h3>Disclosure of Interests</h3> None declared