AIM: Severe forms of idiopathic nephrotic syndrome (INS) require immunosuppressive therapy: oral treatment or intravenous therapy (rituximab, RTX). The main objective was to describe quality of life (QOL) in these specific patients. METHODS: Cross-sectional, multicentre, observational study analysed QOL using a standardised questionnaire in children from 7 to 17 years, with a steroid-dependent or steroid-resistant INS in stable remission. The questionnaire consisted of 30 questions concerning physical and emotional well-being, self-esteem, family, friends, school and disease resulting in a global score of 0-100. RESULTS: A total of 110 patients with a mean age of 11.6 years from three French paediatric nephrology centres were included. A total of 71 patients had oral immunosuppressive treatment, 27 had RTX, and 12 had both. 13.6% of patients had a steroid-resistant INS. The mean number of relapses was 5.8. Seventy-eight patients answered the questionnaire. The global score in the whole study population was 74.7; 72.6 in the RTX group, 76.2 in the oral drugs group, (P = 0.49). The results of sub-dimension 'school' were statistically lower in RTX group (61.6 ± 19.5) compared with oral drugs group (71.4 ± 16; P = 0.02). CONCLUSION: Global QOL score was high in 'difficult-to-treat' patients with INS in stable remission on oral immunosuppressive or RTX treatment.