Characterization of Adult-Type IgA Vasculitis (Henoch-Schönlein Purpura): A Retrospective Study of 122 Cases

The clinical features of adult-type IgA vasculitis have not been well characterized. To analyze the characteristics of IgA vasculitis in adults, patients diagnosed with IgA vasculitis based on EULAR/PRINTO/PRES criteria (2012) in our institution between 2003 and 2012 were studied, comprising 85 adults (age ≥ 21 years) and 37 pediatric patients (≤ 20 years). Compared with pediatric cases, adult disease showed significantly higher serum C-reactive protein and IgA values, a lower percentage of cases was associated with infections (56.5% vs 89.2%, P < 0.001) but there was a greater range of infections affecting different tissues and organs, and there was occasional cases with malignancy (8.2%) including four cases of lung carcinoma and three with hematological disorders. The skin lesions in adults tended to be widely distributed on the abdomen and waist (15.3% vs 2.7%, P = 0.045). Adult cases were associated with greater renal involvement, as evidenced by proteinuria, hematuria and/or urinary casts, compared with the pediatric group (76.2% vs 48.6%, P = 0.003) and disease recalcitrance was also significantly higher (38.8% vs 18.9%, P = 0.031). Examination of the serum levels of immunoglobulins in adults showed that a sole increase in IgA was associated with renal and gastrointestinal manifestations, but this was not seen in cases with concurrent increases of IgA and IgG or IgA, IgG and IgM. Although the retrospective nature of the study is a limitation, it identified possible associations with the wide range of infections, more severe renal damage, and malignancy in adult IgA vasculitis.