Single relapse at ≥ 0.5 mg/kg alternate-day prednisone predicts course of childhood nephrotic syndrome

BACKGROUND: Around half of children with steroid-sensitive nephrotic syndrome are eventually diagnosed with frequently relapsing or steroid-dependent disease. To minimize steroid toxicity, guidelines usually recommend switching these patients to steroid-sparing agents. Unfortunately, morbidity from steroids can be irreversible, and patients may suffer even after steroid discontinuation. METHODS: This is a multicenter observational study of children with steroid-sensitive nephrotic syndrome. We compared patients that were eventually diagnosed with frequently relapsing/steroid-dependent nephrotic syndrome with those with non/infrequently relapsing nephrotic syndrome. Additionally, we compared the risk of being diagnosed with frequently relapsing/steroid-dependent nephrotic syndrome, between patients with relapse on a prednisone dose equivalent of ≥ 0.5 mg/kg/every other day versus patients with no relapses above this cutoff. RESULTS: Patients who relapsed during induction were more likely to develop frequently relapsing/steroid-dependent nephrotic syndrome. Patients with ≥ 1 relapse on prednisone equivalent of ≥ 0.5 mg/kg/every other day were 33 times more likely to develop frequently relapsing/steroid-dependent nephrotic syndrome (p value < 0.001). CONCLUSIONS: Patients with one relapse on prednisone equivalent of ≥ 0.5 mg/kg/every other day are at high risk of an eventual diagnosis of frequently relapsing/steroid-dependent nephrotic syndrome. Further studies are needed to determine whether a single relapse above this cutoff is reliable enough to enable clinicians to switch patients to steroid-sparing agents before meeting formal criteria for frequently relapsing/steroid-dependent disease.