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.
ANCA-associated vasculitides (AAV) are a heterogeneous group of rare diseases with unknown aetiology and the clinical spectrum ranging from life-threatening systemic disease, through single organ ...involvement to minor isolated skin changes. Thus, there is an unmet need for phenotype identification, especially among patients with granulomatosis with polyangiitis (GPA). Patients with microscopic polyangiitis (MPA) seem to be clinically much more uniform. Recently, three subcategories of AAV have been proposed and described as non-severe AAV, severe PR3-AAV, and severe MPO-AAV.
In line with these attempts, we decided to use an unbiased approach offered by latent class analysis (LCA) to subcategorise GPA and MPA in a large cohort of Polish AAV patients included in a multicentre POLVAS registry.
LCA of our AAV group identified a four-class model of AAV, including previously proposed three subphenotypes and revealing a fourth (previously not described) clinically relevant subphenotype. This new subphenotype includes only GPA patients, usually diagnosed at a younger age as compared to other groups, and characterised by multiorgan involvement, high relapse rate, relatively high risk of death, but no end-stage kidney disease.
Based on multiple clinical and serological variables, LCA methodology identified 4-class model of AAV. This newly described fourth class of AAV may be of clinical relevance and may require prompt diagnosis and aggressive treatment due to the multiorgan involvement, high risk of relapse and marked mortality among these relatively young GPA subjects.
The anion radical of the 2′-deoxyadenosine···thymine (dAT•–) pair has been investigated experimentally and theoretically in the gas phase. By employing negative-ion photoelectron spectroscopy (PES), ...we have registered a spectrum typical for the valence-bound anion, featuring a broad peak at the electron-binding energy (EBE) between ∼1.5 and 2.2 eV with the maximum at ∼1.9 eV. The measured value of the adiabatic electron affinity (AEA) for dAT was estimated to be ∼1.1 eV. Calculations performed at the M06-2X/6-31++G(d,p) level revealed that the structure, where thymine is coordinated to the sugar of dA by two hydrogen bonds, is responsible for the observed PES signal. The AEAG and the vertical detachment energy of 0.91 and 1.68 eV, respectively, calculated for this structure reproduce the experimental values well. The role of the possible proton transfer in the stabilization of anionic radical complexes is discussed.
The 2′-deoxyadenosine···2′-deoxythymidine (dAdT•–) radical anion nucleoside pair has been investigated both experimentally and theoretically in the gas phase. The vertical detachment energy (VDE) and ...adiabatic electron affinity (AEA) were determined by anion photoelectron spectroscopy (PES). The measured photoelectron spectrum features a broad band having an onset at ∼1.1 eV and a maximum at the electron binding energy (EBE) ranging from 1.7 to 1.9 eV. Calculations performed at the M06-2X/6-31++G** level reveal that the observed PES signal is probably due to a dAdT•– complex in which the thymine of the dT nucleoside forms hydrogen bonds that engage its O7 and O8 atoms as well as the 3′- and 5′-hydroxyl groups of 2′-deoxyadenosine (dA), while dT’s 3′-hydroxyl group interacts with the N1 of dA. In this heterodimer, the excess electron is entirely located on thymine. The biologically relevant Watson–Crick arrangement of the dAdT•– dimer was found to be substantially less stable (by ∼19 kcal mol–1 in Gibbs free energy scale) than the above-mentioned configuration; hence, it is not populated in the gas phase.