Henoch-Schonlein purpura in 535 Chinese children: clinical features and risk factors for renal involvement

Objectives: To analyse the clinical features of Henoch-Schonlein purpura (HSP) with or without nephritis in Chinese children and to determine the risk factors for renal involvement. Methods: Patient characteristics, clinical parameters and laboratory data were retrospectively analysed in patients with HSP with or without nephritis. Logistic regression analysis was used to identify the risk factors for renal involvement. Results: A total of 535 patients with HSP were included in the study. HSP nephritis occurred in 267 patients (49.9%), ranging from isolated haematuria in 5.2%, mild proteinuria in 77.5%, moderate proteinuria in 6.4% and severe proteinuria in 10.9% of cases. In 90% of the cases, nephritis developed within 1 week of HSP onset; 98.5% of the cases with nephritis developed the condition within 1 month. Risk factors for the development of nephritis were age >= 6 years, purpura on sites other than the lower limbs and the presence of occult blood in the stool. Conclusion: These results suggest that patients aged >= 6 years, or who have purpura on the upper limbs or face, or who have occult blood in the stool should be particularly monitored for signs of nephritis.