Relapses in patients with Henoch–Schönlein purpura

To further investigate into the relapses of Henoch-Schönlein purpura (HSP), we analyzed the frequency, clinical features, and predictors of relapses in series of 417 unselected patients from a single center. After a median follow-up of 12 (interquartile range [IQR]: 2-38) years, almost one-third of the 417 patients (n = 133; 32%; 85 men/48 women) had experienced at least 1 relapse. At the time of disease diagnosis, patients who later experienced relapses had less commonly infections than those who never suffered flares (30.8% vs 41.9%; P = 0.03). In contrast, patients who experienced relapses had a longer duration of the first episode of palpable purpura than those without relapses (palpable purpura lasting >7 days; 80.0% vs 68.1%; P = 0.04). Abdominal pain (72.3% vs 62.3%; P = 0.03) and joint manifestations (27.8% vs 15.5%; P = 0.005) were also more common in patients who later developed relapses. In contrast, patients who never suffered relapses had a slightly higher frequency of fever at the time of disease diagnosis (9.3% vs 3.8%; P = 0.06). At the time of disease diagnosis, corticosteroids were more frequently given to patients who later had relapses of the disease (44% vs 32% in nonrelapsing patients; P = 0.03). Relapses generally occurred soon after the first episode of vasculitis. The median time from the diagnosis of HSP to the first relapse was 1 (IQR: 1-2) month. The median number of relapses was 1 (IQR 1-3). The main clinical features at the time of the relapse were cutaneous (88.7%), gastrointestinal (27.1%), renal (24.8%), and joint (16.5%) manifestations. After a mean ± standard deviation follow-up of 18.9 ± 9.8 years, complete recovery was observed in 110 (82.7%) of the 133 patients who had relapses. Renal sequelae (persistent renal involvement) was found in 11 (8.3%) of the patients with relapses. The best predictive factors for relapse were joint and gastrointestinal manifestations at HSP diagnosis (odds ratio [OR]: 2.22; 95% confidence interval [CI]: 1.34-3.69, and OR: 1.60; 95% CI: 1.01-2.53, respectively). In contrast, a history of previous infection was a protective factor for relapses (OR: 0.60; 95% CI: 0.38-0.94). In conclusion, joint and gastrointestinal manifestations at the time of diagnosis of HSP are predictors of relapses.