Adrenocortical suppression in children with nephrotic syndrome treated with corticosteroids

Abstract

Background: Children with nephrotic syndrome are exposed to alternate day steroids for prolonged periods and this poses the need for evaluation of adrenocortical suppression using the adrenocorticotropic hormone (ACTH) stimulation test.

Methods: This cross-sectional study enrolled children (2-18 years) both with steroid sensitive nephrotic syndrome (SSNS) (n = 27) and steroid resistant (SRNS) (n = 25); those on daily prednisolone or having serious bacterial infections or hospitalized were excluded. The primary objective was to determine prevalence of adrenocortical suppression in those on low dose alternate day steroids for more than 8 weeks or having received > 2 mg/kg/d for > 2 weeks in the past 1 year and currently in remission. A baseline morning fasting sample of serum cortisol was taken and 25 IU of ACTH (Acton Prolongatum*) injected intramuscularly and repeat serum cortisol sample taken after 1 h. All patients with 1 h post ACTH cortisol < 18.0 µgm/dl were diagnosed with adrenal insufficiency. Receiver operating characteristic curve was drawn to predict the prednisolone dose for adrenal insufficiency.

Results: Fifty-two (33 males) children were enrolled (mean age 9.4 years); proportion of adrenal insufficiency was 50% and 64% using baseline and post stimulation cutoffs. The total cumulative annual dose of prednisolone 0.22 mg/kg/day predicted adrenocortical suppression with AUC 0.76 (95% CI 0.63-0.89), with sensitivity of 63.9% and specificity of 81.3%.

Conclusions: A significant proportion of children with nephrotic syndrome were detected with adrenal insufficiency on ACTH stimulation test. A cumulative steroid intake of > 0.22 mg/kg/day on an alternate day basis emerged as a risk factor for predicting adrenocortical suppression.

Keywords: ACTH stimulation; Adrenocortical suppression; Cortisol; Prednisolone; Steroid resistant nephrotic syndrome.