241. Predictors of arthritis, gastrointestinal and renal involvement in adult IgA vasculitis
Creators: name: Alojzija Hocevar1, 2
name: Matija Tomšič1, 2
name: Žiga Rotar1, 2
Publisher: name: Zenodo
Year: 2022
Subjects: Vasculitis
ANCA
Abstracts
Giant Cell Arthritis
MPA
GPA
EGPA
Takayasu
IgA vasculitis

description: <strong>Background:</strong> IgA vasculitis (IgAV) is not an uncommon vasculitis in adults, yet the disease in adults is still poorly defined. The aim of our study was to determine the predictors of arthritis, gastrointestinal (GI) or renal involvement in adult IgAV. <strong>Methods:</strong> Medical records of histologically proven adult IgAV cases diagnosed between January 2013 and September 2021 at our secondary/tertiary rheumatology center were analyzed. The impact of 14 variables (age, gender, current smoking, history of preceding infection, use of new medication prior IgAV, the extent of skin purpura (generalized above the waist vs. localized), skin necroses, constitutional symptoms and the laboratory parameters (erythrocyte sedimentation rate, C reactive protein, haemoglobin, platelets, neutrophil to lymphocyte ratio (NLR) and elevated serum immunoglobulin A (IgA) level) on the presentation of IgAV was evaluated using logistic regression models. <strong>Results:</strong> During the 105-month observation period we identified 268 new adult IgAV patients (60.4% males, median (interquartile range) age 64 (47-76) years). Arthritis, GI tract and renal involvement developed in 35 (13.1%), 66 (24.6%) and 110 (41.0%) cases, respectively. Characteristics of IgAV patients are presented in Table 1. In a multivariate logistic regression model increasing age was associated with a lower risk of arthritis (OR 0.98 (95%CI 0.96 – 0.99), p=0.011). Generalized purpura (OR 5.52 (95%CI 2.66 – 11.44), p&lt;0.001), constitutional symptoms (OR 3. 86 (95%CI 1.69 – 8.79, p=0.001) and NLR (OR 1.22 (95% CI 1.09 – 1.37), p=0.001) emerged as risk factors for GI involvement. Increasing age was negatively associated with development of GI disease (OR 0.98 (95%CI 0.96 – 0.99), p=0.006). Elevated serum IgA (OR 2.58 (95%CI 1.49 – 4.47), p&lt;0.001), current smoking (OR 2.46 (1.27 – 4.75), p=0.007) and age (OR 1.02 (95%CI 1.00 – 1.03), p=0.019,) were all associated with an increased risk of glomerulonephritis in our cohort. <strong>Conclusions:</strong> Age has an important impact on a clinical presentation of adult IgAV. Purpura above waistline is a strong predictor of GI involvement, whereas active smoking and elevated serum IgA are associated with renal involvement. <strong>Disclosures:</strong> Authors have no conflict of interest to declare. <strong>Table 1. </strong>Characteristics of IgAV patients <em>Clinical characteristics</em> <em>IgAV cases (268)</em> <em>Clinical characteristics</em> <em>IgAV cases (268)</em> Male gender (%) 60.4 Skin necroses (%) 46.3 Age (years)* 64 (48–76) Generalized purpura<sup>&amp;</sup> (%) 52.2 Symptom duration (day)* 7 (5–21) Arthritis (%) 13.1 Current smoking (%) 20.9 GI involv. (%) 24.6 New medication (%) 25.4 Severe GI involv. (%) 6.0 Prior infection (%) 30.3 Renal involv. (%) 41.0 Elevated serum IgA (%) 50.0 Severe renal involv. (%) 12.7 Constitutional symptoms 14.2 BVAS-3* 6 (2-13) Legend: * median (IQR); <sup>&amp;</sup> purpura above the waistline; GI gastrointestinal; severe GI involvement - bloody diarrhea or ileus or surgical intervention; severe renal involvement - acute renal failure or nephrotic syndrome; BVAS-3 Birmingham Vasculitis Activity Score –3;