Treatment of childhood nephrotic syndrome with long-term, low-dose tacrolimus

Aim: Children with steroid-resistant (SR) and steroid-dependent (SD) nephrotic syndrome (NS) pose a treatment challenge. Literature on the use of tacrolimus (TAC), a calcineurin inhibitor, for maintenance treatment of NS is sparse. We aimed to evaluate the efficacy and safety of low-dose, long-term TAC for inducing and sustaining remission in children with SD/SR NS. Methods: Data from patients treated at our center from 1999 to 2009 were analyzed. Results: 40 patients with NS were treated with TAO for 3 - 80-month periods (median 25.2 months). Diagnoses included focal segmental glomerulosclerosis (FSGS) (60%), IgM nephropathy (15%), minimal change disease (20%) and membrano-proliferative glomerulonephritis (MPGN) (5%). 58% of patients had been previously treated with alternate agents. After 1, 2, and 3 years on TAO, complete remission was achieved in 26%, 48%, and 29% of patients; complete or partial remission was achieved in 85%, 100%, and 86%, respectively (p < 0.05). Median time to remission was 41 days (range: 10 - 270 days). FSGS and SR diseases were associated with lower likelihood of remission (p < 0.05). Remission was equally likely in both treatment naive patients and those who had received prior second-line agents. Conclusion: Our results demonstrate that TAO treatment for children with SR/SD NS is associated with high rates of sustained remission, even when prior second-line agents failed.