Objective:Children with frequently relapsing nephrotic syndrome (FRNS) are usually treated with long term low dose alternate day prednisolone with or without glucocorticoid sparing therapy such as levamisole or cyclosporine A to maintain remission. The degree of hypothalamic-pituitary-adrenal axis (HPA) suppression with such therapeutic strategies has not been studied systematically. HPA suppression could place a child at risk of a relapse or adrenal crisis.
Study design:To study this possibility further, modified low dose synacthen test (0.5mg) was performed in 32 patients (22M: 10F) aged 3.8-17.6 (mean 9.7) years with NS receiving long-term alternate day prednisolone for over 12 months period. Twelve patients received alternate day prednisolone, 11 alternate prednisolone + levamisole and 9 received alternate prednisolone + cyclosporine A. All patients were followed up for a period of 3 years focusing on the relapse rate.
Results:20/32 (62.5%) had a peak serum cortisol concentration below 500nmol/l suggesting suboptimal cortisol secretion and possible HPA suppression. 10/12 children in the prednisolone group and 8/11 in the levamisole group had a suboptimal cortisol response compared with 2/9 in the cyclosporine A group. During follow up, 20 children who had a suboptimal cortisol response had a significantly greater number of relapses (95 relapses) when compared to the 12 children with a normal cortisol response with 24 relapses (p=0.01).
Conclusions:Children with FRNS receiving long- term alternate day prednisolone therapy are at risk of developing HPA suppression and should be evaluated using modified Synacthen test. The children with evidence of HPA suppression are at a greater risk of relapse.
- glucocorticoid sparing therapy
- glucocorticoid therapy
- synacthen test