Abstract
Background: Recent studies showed that high-dose mizoribine (MZR) therapy may be effective in the management of children with steroid-dependent nephrotic syndrome (SDNS). However, long-term prognosis of the patients following the immunosuppressive agent remains unclear. Patients and methods: We retrospectively analyzed 12 patients with SDNS who received high-dose MZR prior to cyclosporine (CsA) administration. MZR was initiated at a single daily dose of 5 mg/kg administered after breakfast and adjusted to maintain 2-h post-dose MZR levels of approximately 3-5 μg/mℓ. Results: In all but one patient, treatment with MZR (mean MZR dose, 8.6 mg/kg/day; mean C2, 3.4 μg/mℓ) resulted in significant reduction of the mean prednisolone dose from 0.45 to 0.12 mg/kg/day and the mean relapse rate from 1.86 to 0.40 episodes/12 months. Of six patients who were able to discontinue high-dose MZR therapy, only one patient returned to SDNS and was re-treated with MZR during follow-up periods (median 4.2 years). Conclusion: High-dose MZR therapy may allow many patients with SDNS to avoid further toxic immunosuppressive agents such as CsA in the long term.
