Use of the low-dose corticotropin stimulation test for the diagnosis of secondary adrenocortical insufficiency.
OBJECTIVE
To assess the clinical utility and safety of the low-dose corticotropin stimulation test in the diagnosis of secondary adrenocortical insufficiency.


METHODS
Prospective study.


METHODS
Regional hospital, Hong Kong.


METHODS
Seventy-two Chinese patients with suspected secondary adrenocortical insufficiency.


METHODS
Serum cortisol response during the low-dose corticotropin stimulation test, using the insulin tolerance test as the gold standard.


RESULTS
The 30-minute cortisol level during the low-dose corticotropin stimulation test was most closely correlated (r=0.79) with the peak cortisol level achieved during the insulin tolerance test. The optimum sensitivity and specificity of the low-dose corticotropin stimulation test were obtained at a cut-off value of 550 nmol/L or more for the 30-minute cortisol level. Using the insulin tolerance test as the gold standard for comparison, the low-dose corticotropin stimulation test had a sensitivity of 97%, a specificity of 78%, a positive predictive value of 81%, and a negative predictive value of 97% at this cut-off value. The positive likelihood ratio was 4.4 and the negative likelihood ratio 0.04.


CONCLUSIONS
The low-dose corticotropin stimulation test, using the cortisol response at 30 minutes after synacthen 1 microg is a safe, convenient, and sensitive method for screening abnormalities of the hypothalamic-pituitary-adrenocortical axis in Chinese patients suspected of having secondary adrenocortical insufficiency.
Choi
C H
CH
Department of Medicine, Queen Elizabeth Hospital, 30 Gascoigne Road, Kowloon, Hong Kong.
Tiu
S C
SC
Shek
C C
CC
Choi
K L
KL
Chan
F K W
FK
Kong
P S
PS
D000309:Adrenal Insufficiency / Q000175:diagnosis*; D000324:Adrenocorticotropic Hormone / Q000008:administration & dosage; D000328:Adult; D000368:Aged; D004305:Dose-Response Relationship, Drug; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007328:Insulin; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity
D007328:Insulin; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone