Abstract: Objective: To determine the clinical characteristics of 393 inpatients with Henoch-Sch?nlein purpura (HSP) and to analyze the risk factors of renal damage. Methods: The date of 393 patients with HSP was analyzed retrospectively and the relationship among the age at onset, the duration of course, the onset time and renal damage was analyzed by the univariate and multivariate analysis. Results: ① The age at onset ranged from 4 to 18 years old in 296 patients (75.32%). The onset time of HSP was in January and March in majority of the patients. Many patients (24.42%) had an upper respiratory tract infection before the onset of the disease. ② The lesions of purpura located on lower limbs in 392 patients (99.74%), followed by hip and vulva in 165 (41.98%), upper limbers in 115 (29.26%). The lesions in 272 (69.21%) patients disappeared within one month. ③ One hundred and thirty six patients (34.61%) presented with the joint symptoms, 193 (49.11%) with gastrointestinal symptoms, 212 (53.94%) with renal damage manifested with hematuria and proteinuria. ④ The univariate and multivariate analysis showed that renal damage was associated with the age at onset ≥10 years old, the duration of the purpura for more than one month and the high level of IgA (P<0.05). Conclusion: HSP has age and season predilection. The most important inducing factor was upper respiratory tract infection. The risk factors of renal damage included the age at onset ≥10 years old, the duration of the purpura for more than one month and high level of IgA. 

Key words: Henoch-Sch?nlein purpura, renal damage