Abstract

Background: Relapses of nephrotic syndrome are often triggered by viral upper respiratory tract infections (URTIs), possibly mediated by cytokine release.

Objective: To test, in a randomised double-blind placebo-controlled crossover trial, the hypothesis that a small short-term increase in the dose of prednisolone will reduce the release of cytokines and thereby reduce the risk of relapse.

Methods: Sequential patients receiving low-dose (<0.6 mg/kg) prednisolone on alternate days as maintenance therapy were recruited. At the first sign of a presumed viral URTI, all children were examined and randomly allocated to take medicine A or B (containing either prednisolone (5 mg) or placebo) in the first viral URTI, and vice versa in the second. If the criteria for diagnosis of a viral URTI were met, the new medicine was prescribed on alternate days for 1 week at the same dose as that of the prednisolone being taken by the patient on an alternate-day basis. A freshly voided urine sample was tested each morning. The presence of 3+ proteinuria for 3 consecutive days was diagnostic of relapse.

Results: 48 patients were recruited, and 40 completed the trial (29 male; 11 female). Age at entry ranged from 1.5 to 13.2 (median 5.3) years. The relapse rate after viral URTI was 19/40 (48%) in the placebo group and 7/40 (18%) in the prednisolone group (p = 0.014; two-sided probability using Fisher’s exact test).

Conclusion: Prescribing prednisolone daily for 7 consecutive days at the same dose as that taken by the patient on an alternate-day basis at the onset of a presumed viral URTI significantly reduces the risk of relapse in children with steroid-dependent nephrotic syndrome.