The prognosis of Henoch-Schönlein purpura (HSP) nephritis is more severe than originally thought, with a significant portion progressing to deterioration of renal function in adulthood. Proteinuria adversely affects the outcome. The aim of this study was to evaluate the initial single-center results of a treatment protocol for severe HSP nephritis based on the Heaton classification. Age, gender, clinical features and duration of disease follow-up were assessed. Glomerular filtration rate (GFR), urinalysis and 24-hour urinary protein excretion were analyzed. All patients with severe renal involvement were biopsied and a treatment plan was assigned: Class II received oral steroids, Class III (with crescentic nephritis) received additional oral cyclophosphamide 2 mg/kg/d for 12 weeks, and Classes IV and V received azathioprine for 9 months subsequent to the treatment for Class III. All patients received angiotensin converting enzyme (ACE) inhibitors regardless of their blood pressure values. Eighteen patients presenting with severe HSP nephritis, defined as heavy proteinuria and/or decreased renal function, were evaluated. Based on the renal histology, 5, 10, 1 and 2 of the patients were classified as Classes II, III, IV and V, respectively. At presentation, 7 of the patients had impaired renal function with GFR below 75 ml/min/1.73 m2. With the presented treatment schema, all GFR returned to normal at the end of four years of follow-up. There was no proteinuria in any of the patients; only 8 had microscopic hematuria. This preliminary study suggests a stepwise treatment according to the renal histology. The excellent results with complete disappearance of proteinuria and normal renal function justify the use of the aforementioned immunosuppressive protocol with ACE inhibition. Long-term, multicenter controlled studies are needed to verify our results.