Unilateral Adrenalectomy Could Be a Valid Option for Primary Nodular Adrenal Disease: Evidence From Twins

Adrenal Cushing Syndrome: Diagnosis and Management in a 10-Year-Old Boy with Carney Complex

INTRODUCTION

Adrenocorticotropic hormone (ACTH)-independent Cushing syndrome (CS) is very rare condition in children. Primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of CS, which in most cases occurs in the context of Carney complex (CNC). CNC is a rare autosomal-dominantly inherited genetic syndrome, usually due to pathogenic variants of the PRKAR1A (regulatory subunit R1A of the protein kinase A) gene located at 17q22-24. The clinical picture is characterized by spotty skin pigmentation, cardiac, cutaneous, and mammary myxomas, melanocytic schwannomas, endocrinopathies, and tumours of the endocrine glands (mostly adrenal, pituitary, and thyroid).

CASE PRESENTATION

A 10-year-old boy first came to our outpatient clinic due to severe obesity. During the first 3 months of follow-up, the height growth rate was normal, but the response to dietary-behavioural indications was poor in terms of weight loss. Later, 10 months after the last evaluation, there was evidence of significant worsening of obesity, growth failure (growth velocity 0.7 cm/year), arterial hypertension, and the occurrence of violaceous striae at the trunk and root of the limbs. Endocrinological causes of obesity associated with growth failure were investigated. The circadian rhythm of cortisol, ACTH, and cortisoluria were suggestive of ACTH-independent hypercortisolaemia. Iatrogenic causes were ruled out. Adrenal ultrasound and computer tomography scan were performed, which initially indicated the presence of a nodule or hyperplasia of the medial arm of the left adrenal gland. Conversely, magnetic resonance imaging showed a significant increase in the global dimensions of the adrenals with a bilateral micronodular appearance. In light of the association between ACTH-independent hypercortisolism and bilateral micronodular adrenal hyperplasia, a genetic investigation was performed, which found a pathogenic variant of the PRKAR1A gene. The patient was begun on treatment with metyrapone which was well tolerated over a 2-year period. The clinical picture has slightly improved, cortisoluria returned and remains within normal limits, but ACTH suppression persists.

CONCLUSION

This is the first report on the clinical and biochemical effects of 2-year medical treatment with metyrapone of PPNAD-related hypercortisolaemia in a paediatric patient with CNC. Currently, there are no established protocols for the management of hypercortisolism in PPNAD and data are scarce, especially in the paediatric field. Medical therapies may play a role in reducing the need, at least initially, for patients to undergo bilateral adrenalectomy. However, further studies on larger case series are needed to clarify this aspect. In cases of CS due to PPNAD in which medical therapy was the initial approach, in the absence of clear clinical, auxological, and biochemical improvements, metyrapone may have to be discontinued in favour of another approach, including surgery.

Novel PRKAR1A mutation in Carney complex: a case report and literature review

Objective

Carney complex is a rare autosomal dominant syndrome that has been shown to be associated with inactivation due to PRKAR1A mutations. We revealed a novel PRKAR1A gene mutation in Chinese patient with Carney complex and review the literature to enhance understanding of Carney complex.

Case presentation

A 23-year-old Chinese male patient with a family history cardiac myxoma was admitted to our Department of Endocrinology because of central obesity and hyperpigmentation. Physical examination revealed a maximum blood pressure of 150/93mmHg, a waist circumference of 102cm, a weight of 70kg, a height of 170cm, and a BMI of 24.22kg/m2. Additionally, there was spotty skin pigmentation on the lip mucosa, purple striae on the abdomen, thin skin on both legs, and visible veins. Blood examination revealed hypercortisolemia, decreased adrenocorticotropic hormone (ACTH) levels and failure to suppress cortisol with low and high-dose dexamethasone suppression tests. Magnetic resonance imaging (MRI) scan revealed multiple small adrenal nodules and Retroperitoneal neurogenic tumor. Genetic testing showed a novel heterozygous mutation in exon 5 of PRKAR1A (c.500_502 + 8delAAGGTAAGGGC). The patient underwent resection of the right adrenal gland and retroperitoneal neoplasms in 2020. Postoperative pathology following the right adrenal gland resection showed nodular hyperplasia of the adrenal cortex. The pathology from the retroperitoneal tumor resection revealed spindle cell tumors rich in pigment and cells. The patient was diagnosed as Carney complex according to Stratakis CA in 2001 guidelines. After long-term follow-up, the patient's condition was stable, with weight loss, waist circumference reduction, significantly lower cortisol levels, and normal blood lipids.

Conclusion

This case reported a Carney complex in a Chinese patient, characterized clinically by non-ACTH-dependent Cushing's syndrome, familial recurrent cardiac myxomas, psammomatous melanotic schwannoma (PMS) and skin and mucosal pigmentation. A novel subtype of PRKAR1A mutation was discovered, which may affect the characteristics of the PRKAR1A protein and contribute to the development of Carney complex.

The clinical characteristics and pathogenic variants of primary pigmented nodular adrenocortical disease in 210 patients: a systematic review

Aims

Primary pigmented nodular adrenocortical disease (PPNAD), as a rare kind of Cushing's syndrome, is frequently misdiagnosed. To get a better understanding of the disease, we analyzed the clinical characteristics and pathogenic variants of PPNAD.

Methods

Databases were searched, and the pathogenic variants and clinical manifestations of patients were summarized from the relevant articles.

Results

A total of 210 patients in 86 articles were enrolled with a median age of 22 and a female-to-male ratio of 2:1. Sixty-six (31.43%) patients were combined with Carney complex (CNC) and 94.29% were combined with osteoporosis/osteopenia. Among 151 patients who underwent genetic testing, 87.42% (132/151) had pathogenic variants. Six gene mutations (PRKAR1A, PDE11A, PRKACA, CTNNB1, PDE8B, and ARMC5) were detected in the patients. The most common mutation was PKAR1A, accounting for 79.47% (120/151). There was a significant correlation between PRKAR1A pathogenic variant and spotty skin pigmentation in CNC concurrent with PPNAD (p < 0.05). Among pregnant patients with PPNAD, those without surgical treatment and with bilateral adrenalectomy suffered from a high-risk perinatal period. However, patients with unilateral adrenalectomy presented a safe perinatal period.

Conclusions

For young patients with Cushing's syndrome, especially female patients with spotty skin pigmentation and osteoporosis/osteopenia, PPNAD should be considered. Unilateral adrenal resection may be considered as an option for women with fertility needs. In view of the difficulty of PPNAD diagnosis, genetic testing before surgery might be a reasonable option. Patients with PPNAD with spotty skin pigmentation should consider the PRKAR1A pathogenic variant and pay attention to CNC.

Systematic review registration

https://www.crd.york.ac.uk/prospero, identifier CRD42023416988.

Adrenal Cushing's syndrome in children

Adrenal Cushing's syndrome is a rare cause of endogenous hypercortisolism in neonatal and early childhood stages. The most common causes of adrenal CS are hyperfunctioning adrenal tumours, adenoma or carcinoma. Rarer causes are primary bilateral macronodular adrenal hyperplasia (PBAMH), primary pigmented adrenocortical disease (PPNAD) and McCune Albright syndrome. The diagnosis represents a challenge for clinicians. In cases of clinical suspicion, confirmatory tests of hypercortisolism should be performed, similarly to those performed in adults. Radiological imaging should be always combined with biochemical confirmatory tests, for the differential diagnosis of adrenal CS causes. Treatment strategies for adrenal CS include surgery and in specific cases medical drugs. An adequate treatment is associated to an improvement of growth, bone health, reproduction and body composition from childhood into and during adult life. After cure, lifelong glucocorticoid replacement therapy and endocrine follow-up are required, notably in patients with Carney's complex disease.

Treatment of Primary Pigmented Nodular Adrenocortical Disease

Primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of adrenocorticotropin hormone (ACTH)-independent Cushing's syndrome (CS), which mainly occurs in children and young adults. Treatment options with proven clinical efficacy for PPNAD include adrenalectomy (bilateral or unilateral adrenalectomy) and drug treatment to control hypercortisolemia. Previously, the main treatment of PPNAD is bilateral adrenal resection and long-term hormone replacement after surgery. In recent years, cases reports suggest that unilateral or subtotal adrenal resection can also lead to long-term remission in some patients without the need for long-term hormone replacement therapy. Medications for hypercortisolemia, such as Ketoconazole, Metyrapone and Mitotane et.al, have been reported as a preoperative transition for in some patients with severe hypercortisolism. In addition, tryptophan hydroxylase inhibitor, COX2 inhibitor Celecoxib, somatostatin and other drugs targeting the possible pathogenic mechanisms of the disease are under study, which are expected to be applied to the clinical treatment of PPNAD in the future. In this review, we summarize the recent progress on treatment of PPNAD, in which options of surgical methods, research results of drugs acting on possible pathogenic mechanisms, and the management during gestation are described in order to provide new ideas for clinical treatment.

Unilateral or bilateral adrenalectomy in PPNAD: six cases from a single family followed up over 40 years

The most frequent endocrine Carney complex manifestation is a bilateral primary pigmented nodular adrenocortical disease and bilateral adrenalectomy (BA) is therefore its main treatment. In this study, a 40 years follow-up of six members of the same family with heterozygous PRKAR1A germline mutation, is reported over two generations. The first cases, two sisters with severe hyperandrogenism and Cushing syndrome (CS) diagnosed in 1972 at age 14 and 25, were successfully treated with unilateral adrenalectomy (UA). Their two brothers were then diagnosed, one with a CS-related severe osteoporosis treated with BA and the other with CS treated with UA. The second generation was diagnosed with CS signs at 7 and 21 years of age and were treated with BA and UA respectively. Out of the four patients treated with UA, the only event possibly related to CS was spontaneous episode of pulmonary embolism, 30 years after surgery. Hormonal evaluation revealed either eucortisolism in one patient or partial adrenal deficiency in two and mild hypercortisolism in one patient. For the two patients with BA, one of them accidentally died. The second one, surprisingly, recovered progressively normal cortisol secretion and circadian variation. Steroid substitution was stopped 6 years after her surgery and we demonstrated by iodocholesterol scintigraphy the presence of bilateral adrenal remnants. In conclusion, our results of long term evolution of PPNAD patients show that UA in this subset of patients could be considered to treat CS.

Carney Complex Complicated with Primary Pigmented Nodular Adrenocortical Disease without Cushing's Syndrome Recurrence for Five Years after Unilateral Adrenalectomy

We herein report a case of Carney complex (CNC) complicated with primary pigmented nodular adrenocortical disease (PPNAD) after unilateral adrenalectomy. A 44-year-old woman was admitted to our hospital for PPNAD surgery. She had previously undergone surgery for cardiac myxoma and had a PRKAR1A mutation with no family history of CNC. She had Cushing's signs, but her metabolic abnormalities were mild. Adrenal insufficiency due to poor medication adherence was a concern, so she underwent unilateral adrenalectomy. Cushing's signs improved postoperatively and without recurrence for five years. Treatment plans for PPNAD should be determined based on the patient's condition, medication adherence, and wishes.

Bilateral Adrenal Hyperplasia: Pathogenesis and Treatment

Bilateral adrenal hyperplasia is a rare cause of Cushing’s syndrome. Micronodular adrenal hyperplasia, including the primary pigmented micronodular adrenal dysplasia (PPNAD) and the isolated micronodular adrenal hyperplasia (iMAD), can be distinguished from the primary bilateral macronodular adrenal hyperplasia (PBMAH) according to the size of the nodules. They both lead to overt or subclinical CS. In the latter case, PPNAD is usually diagnosed after a systematic screening in patients presenting with Carney complex, while for PBMAH, the diagnosis is often incidental on imaging. Identification of causal genes and genetic counseling also help in the diagnoses. This review discusses the last decades’ findings on genetic and molecular causes of bilateral adrenal hyperplasia, including the several mechanisms altering the PKA pathway, the recent discovery of ARMC5, and the role of the adrenal paracrine regulation. Finally, the treatment of bilateral adrenal hyperplasia will be discussed, focusing on current data on unilateral adrenalectomy.

Role of unilateral adrenalectomy in bilateral adrenal hyperplasias with Cushing's syndrome

Primary bilateral adrenocortical hyperplasias are rare forms of pituitary ACTH-independent Cushing's syndrome (CS). They are divided between primary bilateral macronodular adrenal hyperplasia (PBMAH) and micronodular adrenal hyperplasia (MiBAH), which is subdivided in primary pigmented nodular adrenocortical disease (PPNAD) and isolated micronodular adrenocortical disease (i-MAD). One of the most debated aspects surrounding these entities is their most appropriate therapy. Although bilateral adrenalectomy (BA) has previously been the most utilized therapy for patients with overt CS, recent studies have indicated that unilateral adrenalectomy (UA) can be effective in patients with PBMAH and some with MiBAH with fewer long-term side effects. Medical therapies can also be used for bridging to surgery or rarely in the long-term for these patients. We review the various degrees of CS resulting from PBMAH and MiBAH, with a special focus on their respective therapies including UA, taking into account the recent pathophysiological and genetics findings.

Update on primary micronodular bilateral adrenocortical diseases

PURPOSE OF REVIEW

Primary micronodular bilateral adrenocortical hyperplasias (MiBAH) are rare challenging diseases. Important progress in understanding its pathophysiology and genetics occurred in the last two decades. We summarize those progress and recent data on investigation and therapy of MiBAH focusing on primary pigmented nodular adrenocortical disease (PPNAD).

RECENT FINDINGS

Larger recent cohorts of PPNAD patients from various countries have confirmed their variable Cushing's syndrome phenotypes. Age of onset is earlier than other ACTH-independent Cushing's syndrome causes and the youngest case have now occurred at 15 months. Two retrospective studies identified an increased risk of osteoporotic fractures in PPNAD as compared with other Cushing's syndrome causes. The utility of 6-day oral dexamethasone test to produce a paradoxical increase of urinary-free cortisol in PPNAD was confirmed but the mean fold of increase was of 48%, less than previously suggested. Several new genetic variants of the PRKAR1A gene have been reported in PPNAD or Carney complex (CNC). Remission of Cushing's syndrome with unilateral adrenalectomy was reported in a few patients with PPNAD.

SUMMARY

MiBAH, PPNAD and CNC are rare challenging diseases, but with combined expert clinical and genetic approaches a comprehensive investigation and prevention strategy can be offered to affected patients and families.

Cushing's syndrome: Treatment and new therapeutic approaches

Overt Cushing's syndrome is a severe condition responsible for multiple comorbidities and increased mortality. Effective treatment is essential to reduce mortality, improve comorbidities and long-term quality of life. Surgical resection of the causal lesion(s) is generally the first-line and most effective treatment to normalize cortisol secretion. Adjunctive symptomatic treatments of co-morbidities are often necessary both during the active phase of the disease and for persisting co-morbidities after cessation of hypercortisolism. Second-line treatments include various pharmacological treatments, bilateral adrenalectomy, and radiotherapy of corticotroph tumors. The choice of these treatments is complex, must be performed in a multidisciplinary expert team to be individualized for each patient, and use a shared decision-making approach.

Cushing's syndrome - Disease monitoring: Recurrence, surveillance with biomarkers or imaging studies

Pituitary surgery is the first-line treatment for patients with Cushing's disease. For patients who are not considered candidates for pituitary surgery, pituitary radiation and bilateral adrenalectomy are further treatment alternatives. Not all patients are cured with pituitary surgery, and a substantial number of patients develop recurrence, sometimes many years after an apparently successful treatment. The same applies to patients treated with radiotherapy. Far from all patients are cured, and in many cases the disease recurs. Bilateral adrenalectomy, although always curative, causes chronic adrenal insufficiency and the remaining pituitary tumour can continue to grow and cause symptoms due to pressure on adjacent tissues, a phenomenon called Nelson's syndrome. In this paper the rate of recurrence of hypercortisolism, as well as the rate of development of Nelson's syndrome, following treatment of patients with Cushing's syndrome, will be reviewed. The aim of the paper is also to summarize clinical and biochemical factors that are associated with recurrence of hypercortisolism and how the patients should be monitored following treatment.