Clinical significance of the anti-Nucleolar Organizer Region 90 antibodies (NOR90) in systemic sclerosis: Analysis of the European Scleroderma Trials and Research (EUSTAR) cohort and a systematic literature review.

BACKGROUND: The anti-Nucleolar Organizer Region 90 antibodies (NOR90) are rare antinuclear antibodies (ANA) reported in systemic sclerosis (SSc). Especially due to low prevalence, the clinical relevance of NOR90 in SSc remains uncertain. OBJECTIVES: To analyze the clinical associations of NOR90 in patients with SSc in a multicentric cohort. METHODS: Post-hoc, cross-sectional study of prospectively collected data from the European Scleroderma Trials and Research (EUSTAR) database, with additional information on NOR90. Further, we performed a systematic literature search, using the terms "systemic sclerosis" and "NOR90" across three databases: Medline via PubMed, Scopus, and Thomson Reuters' Web of Science Core Collection, from inception to November 1st, 2023. RESULTS: Overall, 1318 patients with SSc were included (mean age 58.3 ± 13.7 years, 81.3 % female), of whom 44 (3.3 %) were positive for NOR90. Of these, 32 were also positive for one of the SSc-criteria antibodies: 9/44 (20.5 %) for anti-topoisomerase I, 18/42 (42.9 %) for anti-centromere, and 5/40 (12.5 %) for anti-RNA polymerase III. NOR90-positive patients were more frequently female, had lower modified Rodnan skin score (mRSS), and lower prevalence of upper and lower gastrointestinal (GI) symptoms compared to NOR90-negative patients. In multivariable analysis, NOR90 remained significantly associated with lower mRSS and less frequent GI symptoms. The literature search identified 17 articles, including a total number of 87 NOR90-positive out of 3357 SSc patients, corresponding to an overall prevalence of 2.6 %. CONCLUSION: To our best knowledge, this is the largest SSc cohort tested for NOR90 to date, confirming the NOR90 prevalence in SSc patients is around 3 %.

Clinical characteristics of Polish patients with ANCA-associated vasculitides-retrospective analysis of POLVAS registry.

OBJECTIVE: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are rare small to medium-size vessel systemic diseases. As their clinical picture, organ involvement, and factors influencing outcome may differ between countries and geographical areas, we decided to describe a large cohort of Polish AAV patients coming from several referral centers-members of the Scientific Consortium of the Polish Vasculitis Registry (POLVAS). METHODS: We conducted a systematic multicenter retrospective study of adult patients diagnosed with AAV between Jan 1990 and Dec 2016 to analyze their clinical picture, organ involvement, and factors influencing outcome. Patients were enrolled to the study by nine centers (14 clinical wards) from seven Voivodeships populated by 22.3 mln inhabitants (58.2% of the Polish population). RESULTS: Participating centers included 625 AAV patients into the registry. Their distribution was as follows: 417 patients (66.7%) with GPA, 106 (17.0%) with MPA, and 102 (16.3%) with EGPA. Male-to-female ratios were almost 1:1 for GPA (210/207) and MPA (54/52), but EGPA was twice more frequent among women (34/68). Clinical manifestations and organ involvement were analyzed by clinical phenotype. Their clinical manifestations seem very similar to other European countries, but interestingly, men with GPA appeared to follow a more severe course than the women. Fifty five patients died. In GPA, two variables were significantly associated with death: permanent renal replacement therapy (PRRT) and respiratory involvement (univariate analysis). In multivariate analysis, PRRT (OR = 5.3; 95% confidence interval (CI) = 2.3-12.2), respiratory involvement (OR = 3.2; 95% CI = 1.06-9.7), and, in addition, age > 65 (OR = 2.6; 95% CI = 1.05-6.6) were independently associated with death. In MPA, also three variables were observed to be independent predictors of death: PRRT (OR = 5.7; 95% CI = 1.3-25.5), skin involvement (OR = 4.4; 95% CI = 1.02-19.6), and age > 65 (OR = 6.3; 95% CI = 1.18-33.7). CONCLUSIONS: In this first multicenter retrospective study of the Polish AAV patients, we have shown that their demographic characteristics, disease manifestations, and predictors of fatal outcome follow the same pattern as those from other European countries, with men possibly suffering from more severe course of the disease.

Skeletal muscle relaxants inhibit rat tracheal smooth muscle tone in vitro.

Neuromuscular blocking drugs (NMBD) can inhibit not only nicotinic but also muscarinic (M) receptors and thereby affect not only skeletal but also smooth muscle (SM) tone. A selective postjunctional muscarinic inhibition would relax, while prejunctional inhibition of muscarinic M2 receptor might hasten SM contraction thereby increasing the risk of bronchospasm. In rat tracheal rings in vitro we evaluated the effects of cumulative concentrations of some NMBD and M receptor blocking agents for their effects on tracheal smooth muscle (TSM) tone pre-contracted with carbachol (CARB; 5 x 10(-7)M or 10(-6)M), pilocarpine (PILO; 5 x 10(-6)M), or by electrical field stimulation. The NMBDs produced relaxation in the preparations precontracted with CARB or PILO. The order of potency after CARB (10(-6)M) was (EC(50)): 4-DAMP (9.8) >atropine (9.2) >methoctramine (6.4) >pancuronium (6.0) >mivacurium (5.8) >cisatracurium (5.6) >gallamine (5.2) >rocuronium (4.8) >succinylcholine (2.9); NMBDs also partially prevented contraction elicited by the electrical field stimulation. We demonstrated that the clinically used NMBD that were examined produced rat TSM relaxation, probably by predominantly blocking postjunctional muscarinic receptors.