Clinical review of adult Henoch–Schönlein purpura and analysis of predictors related to gastrointestinal involvement

Background Henoch–Schönlein purpura (HSP) is a small-vessel vasculitis characterized by non-thrombocytopenic purpura, often involving the gastrointestinal tract, joints, kidneys, and other organs. While most studies on HSP focus on children, severe manifestations and poor outcomes are more frequently observed in adults. Objective This retrospective study aimed to evaluate predictors associated with gastrointestinal (GI) involvement in adult patients. Methods We included 206 adult patients with HSP, categorized into subgroups based on the presence of gastrointestinal involvement. Results Among the 206 patients, 22.82% had gastrointestinal (GI+) involvement, while 77.18% had non-gastrointestinal (GI−) involvement. The GI+ group exhibited significantly higher rates of skin lesions extending to both lower limbs, atypical rashes such as blisters and necrosis, and joint involvement compared to the GI− group ( P < 0.05). Multivariate analysis identified elevated D-dimer levels (> 1,040 μg/L) as an independent predictor for gastrointestinal involvement (OR = 1.460, 95% CI: 1.151–1.852, P < 0.05). Conclusions Adult HSP patients with gastrointestinal involvement are more likely to present with extensive skin lesions, atypical rashes, and joint involvement; may be at risk of misdiagnosis; and have elevated D-dimer levels.