J Endocrinol Metab

Journal of Endocrinology and Metabolism, ISSN 1923-2861 print, 1923-287X online, Open Access

Article copyright, the authors; Journal compilation copyright, J Endocrinol Metab and Elmer Press Inc

Journal website https://www.jofem.org

Case Report

Volume 12, Number 1, February 2022, pages 40-48

Cushing’s Disease of Unknown Etiology: A Clinical Case Report

Figures

Figure 1. Physical habitus of patient.

Figure 2. First MRI study showing diffuse enlargement of the whole pituitary gland. MRI: magnetic resonance imaging.

Figure 3. Pathologic sample removed at surgery. (a) Pituitary adenoma solid pattern, with cells with clear or eosinophilic cytoplasm (hematoxylin and eosin stain, × 200). (b) Scarcity of the reticulin net (Gomori stain × 200). (c) ACTH immunostain (× 200). ACTH: adrenocorticotropic hormone.

Figure 4. Last MRI study with marked widening of the pituitary stalk. MRI: magnetic resonance imaging.

Tables

**Table 1.** Circadian Rhythm and Rapid Overnight Dexamethasone (1.0 mg PO at 24 h) Test
	9 h	19 h	24 h	8 h (post Dex)
ACTH: adrenocorticotropic hormone; PO: orally; Dex: dexamethasone.
ACTH (pg/mL)	48	36	32	17
Cortisol (µg/dL)	20	14	14	9

**Table 2.** Prolonged Low (Dexamethasone 0.5 mg 6/6 h for 48 h) and High (Dexamethasone 2 mg 6/6 h for 48 h) Tests
	24 h	48 h	72 h	96 h
ACTH: adrenocorticotropic hormone.
ACTH (pg/mL)	34	46	8	12
Cortisol (µg/dL)	8	15	0.7	0.7

**Table 3.** CRH Test (hCRH 100 µg, IV, Bolus at Time 0)
	0 min	5 min	10 min	15 min	30 min	60 min	120 min
IV: Intravenous; CRH: corticotropin-releasing hormone; ACTH: adrenocorticotropic hormone.
ACTH (pg/mL)	44	39	42	47	57	70	57
Cortisol (µg/dL)	32	29	28	29	31	35	33