Identifying distinct clinical phenotypes and outcomes in adult-onset IgA vasculitis using unsupervised clustering analysis
Year: 2026
Type: article
Study design: Observational Study
Abstract: OBJECTIVE: IgA vasculitis (IgAV) is a small-vessel vasculitis. The diversity of clinical presentations and outcomes requires the identification of groups with a distinct phenotype for management and follow-up. METHODS: The French retrospective IGAVAS database (n = 260) includes adult-onset IgAV. Agglomerative hierarchical clustering was performed, using k-means and Ward's method, based on 7 parameters (sex, age, constitutional symptoms, skin necrosis, joint and digestive involvement, abnormal kidney function). These results were validated on an independent cohort of Slovenian patients (n = 208). RESULTS: Of 260 IgAv patients, 3 identified clusters were identified. Cluster 1 (n = 114, 44%) included a majority of men (68%), of young age (median 42 years), with gastrointestinal (100%) and joint (77%) involvement, with low rate of renal insufficiency (7%). Cluster 2 (n = 96, 37%) included 56% males, with a mean age of 49 years, without gastro-intestinal involvement, and 4% renal insufficiency. Cluster 3 (n = 50, 19%, 66% men) included older patients (mean age 70 years), with skin necrosis (52%), and abnormal kidney function (90%). Very similar clusters were found in the Slovenian cohort. Of the 144 renal biopsies available, cluster 3 had more tubulointerstitial damage, there was no significative difference of extracapillary proliferation. Regarding outcome, cluster 1 an 2 tended to have more relapses (20 and 25%), cluster 3 had more residual chronic renal failure (79%). DISCUSSION: Through this clustering study, validated in an independent cohort, three very distinct groups in adult-onset IgAV emerged with clear-cut presentations and outcomes. This approach enables a personalized evaluation to be proposed at baseline and during the follow-up.
Authors: Valentin Maisons, Antoine Hankard, Alojzija Hočevar, Evangeline Pillebout, Jean-Michel Halimi, Bénédicte Sautenet, Christelle Barbet, Noémie Jourde-Chiche, Alexandre Karras, Jean-François Augusto, Xavier Puéchal, Stanislas Faguer, Christian Lavigne, Kim Baud, Alexis Archambeaud, Hubert de Boysson, Achille Aouba, François Maillot, Benjamin Terrier, Yann Nguyen, Alexandra Audemard-Verger
Institutions: Université de Tours, Inserm, Centre Hospitalier Universitaire de Tours, methodS in Patient-centered outcomes and HEalth ResEarch, Université de Nantes, Nantes Université, Centre Hospitalier Universitaire de Caen Normandie, University of Ljubljana, Ljubljana University Medical Centre, Hôpital Saint-Louis, Hôpital de la Conception, Hôpital Européen Georges-Pompidou, Centre Hospitalier Universitaire d'Angers, Hôpital Cochin, Centre Hospitalier Universitaire de Toulouse, Hôpital Rangueil, Université Paris Cité, Assistance Publique – Hôpitaux de Paris, Hôpital Beaujon, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Université Sorbonne Paris Nord, Centre de Recherche Épidémiologie et Statistique
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $3,520
OpenAlex ID: W7128071514