Table 1 Recommended screening tests in adrenal incidentalomas

Table 1 Recommended screening tests in adrenal incidentalomas. Additional analyses in bilateral incidentalomas listed below will depend on the clinical presentation and family history.

Recommended screening Test for all incidentalomas Cushing's syndrome Pheochromocytoma Primary aldosteronism (screen only in hypertensive patients) 1 mg overnight dexamethasone suppression test 24 -hour urine collection for fractionated metanephrines and catecholamines Plasma aldosterone to plasma renin activity ratio

screening recommended for Test bilateral incidentalomas Adrenal insufficiency Morning cortisol and ACTH (or corticotrophin stimulation test) MEN 2 RET gene mutation analysis, evaluation for hyperparathyroidism, medullary thyroid cancer, or mucosal neuromas Von Hippel-Lindau syndrome VHL gene mutation analysis and evaluation for additional tumors (such as renal, retinal, or nervous system) Neurofibromatosis type 1 NF 1 gene mutation analysis Pheochromocytomaparaganglioma syndrome SDHB/SDHD gene mutation analysis

Conn’s syndrome (adrenal aldosteroneproducing adenoma) and bilateral adrenal hyperplasia are the most common causes of primary aldosteronism. The treatment of choice for patients with aldosterone-producing adenoma is unilateral total adrenalectomy. Recurrence after adequate surgery is exceptional.

A 62 -year-old woman was admitted to the hospital because of severe hypokalemia and poorly controlled hypertension. She underwent adenomectomy for primary aldosteronism due to right APA 9 years ago. The pathological examination revealed a 2 -cm diameter adenoma without other abnormalities. After surgery, she had been asymptomatic with normotension and normokalemia without pharmacologic treatment

In the follow-up repeated plasma renin activity and serum aldosterone levels were normal. Six months before admission, hypertension resistant to antihypertensive poly therapy, weakness and paraesthesias developed. At entry, her medications comprised fosinopril (20 mg daily), amlodipine (10 mg daily) and hydrochloroiazide (25 mg daily). There was no family history of hypertension.

A physical examination showed only moderate obesity. The blood pressure was 160/110 mm. Hg. Blood chemistry showed: urea 4. 3 nmol/l, creatinine 52 μmol/l, sodium 143 mmol/l, potassium 2. 4 mmol/l and chloride 96 mmol/l. Haematology, chest X-ray and electrocardiogram were normal.

On free dietary sodium intake, measured supine at 08. 00 h before she arose, plasma aldosterone concentration was 3575 pmol/l (normal range 41– 412 pmol/l)and plasma renin activity was undetectable. Upright at 08. 00 h, plasma aldosterone con-centration and plasma renin activity were 2550 pmol/l (137– 825 pmol/l) and undetectable, respectively. Plasma aldosterone concentration before and after saline loading was 3230 pmol/land 3055 pmol/l, respectively.

The 24 -hour urinary free cortisol was 120 nmol (75– 250 nmol). The 08. 00 h basal cortisol was 223 nmol/l (140– 690 nmol/l). The 08. 00 h cortisol after dexamethasone suppression (1 mg at 23. 00 h) was 47 nmol/l. The 24 -hour urinary free catecholamines, dopamine, epinephrine and norepinephrine were normal.

Adrenal adenomas can be differentiated from metastases by adrenal MRI. A hyperintense rim in T 1 - and. T 2 -weighted sequences is characteristic for adenomas, as in our case.

We describe the recurrence of an adrenal APA 9 years after adenomectomy, which is extremely rare; to our knowledge, only two such cases have previously been reported in the literature.

The resected adrenal gland sometimes contains macro- or micro-nodular lesions in addition to APA. These nodules are multiple and generally bilateral and lead to a more complex diffrential diagnosis than the presence of a unilateral solitary mass. This bilateral nodularity is not synonymous with hyperplasia, and adrenal venous sampling is required to detect cases of surgically correctable APA. The clinical significance of these nodular lesions in patients with APA is not fully clear. They are not thought to contribute to recurrence but to result from intractable hypertension.

Autopsy studies suggest a prevalence of incidentalomas of around 2% (range 1. 0– 8. 7%), increasing with age. Radiological studies report a frequency close to 3% in patients below the age of 50 years, increasing up to 10% in the elderly. Childhood incidentalomas are extremely rare.

Rationale Bilateral adrenal masses usually represent benign adenomas, macronodular hyperplasia or distinct bilateral nodules. In the relevant clinical setting, metastases (especially in patients with known malignancy), lymphoma or pheochromocytomas should also be considered. Each lesion should be evaluated individually as bilateral adrenal masses can represent cooccurrence of different lesions.

IMPORTANCE Adrenal incidentalomas are found in 1% to 5% of abdominal cross-sectional imaging studies. Although the workup and management of unilateral lesions are well established, limited information exists for bilateral incidentalomas. OBJECTIVETo compare the natural history of patients having bilateral incidentalomas with those having unilateral incidentalomas. DESIGN, SETTING, AND PARTICIPANTS Retrospective analysis of a prospective database of consecutive patients referred to an academic multidisciplinary adrenal conference. The setting was a tertiary care university hospital among a cohort of 500 patients with adrenal lesions between July 1, 2009, and July 1, 2014

RESULTS 23 patients with bilateral incidentalomas and 112 patients with unilateral lincidentalomas were identified. The mean age at diagnosis of bilateral lesions was 58. 7 years. The mean lesion size was 2. 4 cm on the right side and 2. 8 cm on the left side. Bilateral incidentalomas were associated with a significantly higher prevalence of subclinical Cushing syndrome (21. 7%[5 of 23] vs 6. 2%[7 of 112]) (P =. 009) and a significantly lower prevalence of pheochromocytoma (4. 3%[1 of 23] vs 19. 6%[22 of 112]) (P =. 003) compared with unilateral lesions, while rates of hyperaldosteronism were similar in both groups (4. 3%[1 of 23] vs 5. 4%[6 of 112]) (P >. 99). Only one patient with bilateral incidentalomas underwent unilateral resection. The mean followup was 4 years (range, 1. 2 -13. 0 years). There were no occult adrenocortical carcinomas.

Abstract A 50 -year-old male patient with a 15 -year history of hypertension was referred to our hospital for evaluation of bilateral adrenal tumors. No Cushingoid features were observed. Computed tomographic scan showed 10 -mm masses in each adrenal gland. Preoperative endocrinological examinations revealed autonomous cortisol and aldosterone secretion in this patient. The results of a subsequent adrenal venous catheterization study were consistent with the presence of a left cortisol-producing tumor and a right aldosterone-producing tumor. A left partial adrenalectomy was performed initially, but cortisol and aldosterone over-secretion persisted. Accordingly, the patient underwent a right adrenalectomy. Pathological examination of the resected specimens, including immunohistochemical analysis, demonstrated that both adenomas possibly produced cortisol and aldosterone. This is an extremely rare case of bilateral adrenal tumors, in which the left adrenocortical tumor produced and secreted cortisol or both cortisol and aldosterone and the right one produced and secreted both aldosterone and cortisol, as confirmed by clinical findings and pathological studies using immunohistochemical analysis.

Approximately 15% of adrenal incidentalomas occur bilaterally. Whereas most unilateral masses are benign or nonfunctional, the bilateral adrenal mass is more likely metastatic disease, hemorrhage, infiltrative disease, congenital adrenal hyperplasia, macronodular Cushing's syndrome, or bilateral cortical adenomas. A Bilaterl pheochromocytomas are also possible, especially as part of a familial syndrome.

Primary bilateral macronodular adrenal hyperplasia is a rare cause of Cushing's syndrome and is more often diagnosed as bilateral adrenal incidentalomas with subclinical cortisol production.