[Clinical characteristics of 16 patients suspected preclinical Cushing's syndrome].
OBJECTIVE
In 1996, Japanese guidelines for the diagnosis of preclinical adrenal Cushing's syndrome were proposed. However, several patients with preclinical Cushing's syndrome (PCS) didn't clearly show that these diagnostic guidelines were universally applicable. The aim of the present study was to evaluate the validity of these diagnostic guidelines on the basis of our clinical experience.


METHODS
We performed adrenalectomy for adrenal incidentaloma in 16 patients with suspected PCS at our university hospital from 1990 through 2002. Eight patients met the Japanese criteria for the diagnosis of PCS (PC group) and 8 did not (dexamethasone [DXM] suppression group). Clinical characteristics and pathology profiles were compared between the groups.


RESULTS
No patients in the DXM suppression group showed responses of serum cortisol levels on a 1-mg overnight dexamethasone suppression test. Twenty-four-hour urinary levels of 17-hydroxycorticosteroids were significantly higher in the PC group than in the DXM suppression group. In all patients of both groups, adrenal scintigraphy showed marked accumulation of radioisotope in the adhesive, atrophic adrenal cortex. One patient of the DXM suppression group had severe adrenal symptoms after adrenalectomy. Several patients in the DMX suppression group showed clinical improvement after adrenalectomy, as well as did several patients in the PC group.


CONCLUSIONS
Endocrine activity may have been higher in the PC group than in the DXM suppression group. However, because patients who failed a 1-mg DXM suppression test may in fact have autonomous cortisol secretion, adrenalectomy may still be indicated. Autonomous cortisol secretion might not be documented with the 1-mg overnight DXM suppression test; therefore, the results must be interpreted carefully.
Department of Urology, Jikei University School of Medicine.
Haruhisa
H
Koide
Nozomu
N
Furuta
Hiroki
H
Yamada
Hiroyuki
H
Ito
Kouichi
K
Kishimoto
Isao
I
Ikemoto
Yukihiko
Y
Oishi
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D003480:Cushing Syndrome / Q000175:diagnosis* / Q000473:pathology; D003907:Dexamethasone; D005260:Female; D019983:Guideline Adherence / Q000592:standards*; D017408:Guidelines as Topic; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D008875:Middle Aged
D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone