Comparison of two low-dose adrenocorticotropic hormone stimulation tests for evaluating adrenal function in children with primary nephrotic syndrome / 中华实用儿科临床杂志

ABSTRACT

Objective To compare 2 kinds of low-dose in adrenocorticotropic hormone(ACTH) stimulation tests for evaluating adrenal function in children with primary nephrotic syndrome(PNS).Methods Seventeen patients (dose of prednisone ＜ 1 mg/kg) with PNS (PNS group) and 7 control subjects (control group) were enrolled.On the first day,all subjects were injected ACTH intravenously at 8 ∶ 00.Serum cortisol was measured just before the ACTH administration,after 20,30 minutes(the first method).On the second day,all subjects were injected ACTH intravenously at 14 ∶ 00.After the ACTH injection,blood was taken every 10 minutes for a period of 1 h to measure serum cortisol (the second method).Adrenal function was evaluated.Cortisol levels of 497 nmol/L or more were taken as normal adrenal response to low dose of ACTH stimulation.Results In the control group,all subjects showed normal adrenal function with the first method and the second method.Cortisol levels at 30 minutes were all ＞ 497 nmol/L.Cortisol levels at 0,20 and 30 min points with the first method did not differ from those with the second method(all P ＞ 0.05).In 17 PNS patients,3 cases (17.65％)and 7 cases (41.18％)showed subnormal responses with the first method and the second method,respectively.Detection rate of subnormal responses was significantly higher with the second method (P ＜0.05).In the first method,5 cases of the 17 patients showed subnormal responses at 20 minutes and 2 of above 5 cases turned to normal responses at 30 minutes.However,10 cases of the 17 patients showed subnormal responses at 20 minutes and none of above 10 cases achieved normal responses at 30 minutes with the second method.Comparison of function of adrenal cortex at 20 and 30 minutes showed that there were difference in the first and second method(P =0.025,0.008,respectively).Comparison of cortisol levels at 0,20 and 30 minutes in the first and the second method showed that there were difference at 0 minute and amplification of 20-30 minutes and there was no difference at any other points.Conclusions The low dose of ACTH test in the second method for evaluation of adrenocortical function in children with PNS is more accurate and sensitive.