Late-onset IgA vasculitis in adult patients exhibits distinct clinical characteristics and outcomes.

OBJECTIVES: The aim of this study was to determine whether adult IgA vasculitis patients who developed the disease at an older age differ from early-onset patients in terms of clinical features and outcomes.

METHODS: All consecutive adult patients who were diagnosed with IgA vasculitis between January 1997 and December 2014 were reviewed retrospectively. Patients who developed the disease at an older age (≥60 years; late-onset) were compared with those with an earlier onset of disease (<60 years; early-onset). Renal insufficiency was defined as an estimated glomerular filtration rate <60 ml/minute.

RESULTS: In total, 100 adult patients were diagnosed with IgA vasculitis (mean age, 45.61 ± 17.24 years), of whom 31 (31%) had late-onset disease. Compared to early-onset patients, late-onset patients were less likely to have a preceding upper respiratory tract infection (0/31, 0.0% vs. 14/69, 20.3%; p=0.004), and more likely to have renal involvement at presentation (27/31, 87.1% vs. 43/69, 62.3%; p=0.017). At the last follow-up visit, late-onset patients were more likely to have chronic renal insufficiency, including end-stage renal disease (18/28, 64.3% vs. 7/62, 11.3%; p=0.000). Multivariate Cox analysis revealed that late-onset was a significant risk factor for renal insufficiency at follow-up (hazard ratio, 16.980, 95% confidence intervals, 4.380-65.830; p=0.000).

CONCLUSIONS: Patients with late-onset IgA vasculitis in adults exhibit distinct clinical features characterized by greater renal involvement and worse renal outcomes. Thus, watchful follow-up might be needed for adult IgA vasculitis patients, in particular those with late-onset disease.