HORMONAL AND RADIOLOGICAL EVALUATION OF ADRENAL GLANDS IN PATIENTS WITH RENAL AMYLOIDOSIS: IMPORTANCE OF LOW DOSE ACTH STIMULATION TEST FOR ASSESSMENT MILD ADRENOCORTICAL INSUFFICIENCY

The aim of the present study was to evaluate the usefullnes of low dose ACTH stimulation test for both assesment of adrenal function and determination mild adrenal insufficiency, and to determine adrenal gland sizes radiologically in patients with renal amyloidosis. 14 patients with renal amyloidosis as patient group and 10 healthy subjects as control group were included in the study, and intravenous ACTH stimulation tests were performed with 15 days interval as 1 μg low dose and 250 μg high dose.The criteria for normal response to ACTH stimulation test were determined as peak Cortisol level higher than 18.0 μ^dl (500 nmol IL). All healthy controls and 13 of 14 patients with amyloidosis had at least one of above mentioned criteria; but serum Cortisol response to low dose ACTH stimulation test in patients with amyloidosis was insufficient. This patient responsed sufficiently to high dose ACTH stimulation test. Although no difference was seen in peak serum Cortisol response between doses and groups, time for reaching peak levels after high dose ACTH stimulation test were delayed in both groups. In our study adrenal gland sizes were assessed with CT and left adrenal gland's maximal width were significantly higher in patient group (p=0.01). Our findings support that in patients with renal amyloidosis adrenal gland were increased in size, and in these patients low dose ACTH stimulation test is sensitive and useful for detecting mild adrenal insufficiency.