1. Cryoglobulins, cryofibrinogens, and cold agglutinins in cold urticaria : literature review, retrospective patient analysis, and observational study in 49 patientsKatharina Ginter, Dalia Melina Ahsan, Mojca Bizjak, Karoline Krause, Marcus Maurer, Sabine Altrichter, Dorothea Terhorst, 2021, original scientific article Abstract: Introduction: Cryoproteins, such as cryoglobulins, cryofibrinogens and cold agglutinins, precipitate at low temperatures or agglutinate erythrocytes and dissolve again when warmed. Their pathogenetic and diagnostic importance in cold urticaria (ColdU) is unclear. In this study, we aimed to characterize the prevalence of cryoproteins in patients with ColdU. Methods: We conducted 3 analyses: i) a systematic review and meta-analysis of published data using an adapted version of the Johanna Briggs Institute's critical appraisal tool for case series, ii) a retrospective analysis of 293 ColdU patients treated at our Urticaria Center of Reference and Excellence (UCARE) from 2014 to 2019, and iii) a prospective observational study, from July 2019 to July 2020, with 49 ColdU patients as defined by the EAACI/GA2LEN/EDF/UNEV consensus recommendations. Results: Our systematic review identified 14 relevant studies with a total of 1151 ColdU patients. The meta-analyses showed that 3.0% (19/628), 1.1% (4/357) and 0.7% (2/283) of patients had elevated levels of cryoglobulins, cryofibrinogens, and cold agglutinins, respectively. Our retrospective analyses showed that cryoproteins were assessed in 4.1% (12/293) of ColdU patients. None of nine ColdU patients had cryoglobulins, and one of 5 had cold agglutinins. In our prospective study, none of our patients had detectable cryoglobulins (0/48) or cryofibrinogens (0/48), but 4.3% (2/46) of patients had cold agglutinins (without any known underlying autoimmune or hematological disorder). Conclusion: Our investigation suggests that only very few ColdU patients exhibit cryoproteins and that the pathogenesis of ColdU is driven by other mechanisms, which remain to be identified and characterized in detail. Keywords: urticaria, review, observational study, retrospective studies, cold urticaria, cryoglobulins, cryofibrinogens, cold agglutinins, retrospective analysis Published in DiRROS: 28.05.2021; Views: 1490; Downloads: 1178 Full text (439,60 KB) This document has many files! More... |
2. Evidence of B cell clonality and investigation into properties of the IgM in patients with Schnitzler syndromeShelly Pathak, Dorota Rowczenio, Samuel Lara-Reyna, Mark Kačar, Roger Owen, Gina Doody, Karoline Krause, Helen J Lachmann, Rainer Doffinger, Darren Newton, Sinisa Savic, 2020, original scientific article Abstract: The Schnitzler Syndrome (SchS) is an acquired, autoinflammatory condition successfully treated with IL-1 inhibition. The two main defining features of this late-onset condition are neutrophilic urticarial dermatoses (NUD) and the presence of an IgM monoclonal component. While the former aspect has been extensively studied in this disease setting, the enigmatic paraproteinaemia and its potential consequential effects within SchS, has not previously been thoroughly addressed. Previous studies analyzing clonal B cell repertoires have largely focused on autoimmune disorders such as Systemic Lupus Erythematous (SLE) and hematological malignancies such as Chronic Lymphocytic Leukaemia (CLL), where B-cell clonality is central to disease pathology. The present study uses next-generation sequencing to provide detailed insight into aspects of B cell VDJ recombination and properties of the resulting immunoglobulin chains. An overview of IgH regional dynamics in 10 SchS patients, with a particular focus on CDR3 sequences and VDJ gene usage is reported, highlighting the presence of specific B cell expansions. Protein microarray detected a substantial proportion of autoreactive IgM to nuclear target proteins, though a single universal target was not identified. Together, these genetic and functional findings impart new understanding into this rare disorder. Keywords: Schnitzler syndrome, B-lymhocytes, paraproteinemias, pararoteins, immunoglobulin M, autoinflammatory diseases, IgM Published in DiRROS: 08.04.2021; Views: 1514; Downloads: 1018 Full text (1003,75 KB) This document has many files! More... |