Prolonged remission of severe Cushing syndrome without adrenalectomy in an infant with McCune-Albright syndrome

Cushing syndrome as a failed cardiac screen in a patient with McCune–Albright syndrome: a case report

Background

McCune–Albright syndrome is a complex disorder encompassing multiple endocrinopathies. These manifestations are secondary to a mutation in the stimulatory G-protein alpha subunit. Cushing syndrome is due to autonomous secretory function of the adrenal gland and is present in 7.1% of patients with McCune–Albright syndrome. Cardiac newborn screenings assist in the identification of critical congenital heart disease. These screenings have become part of routine postnatal care nationwide.

Case report

A 6-week-old Caucasian male presented to a cardiologist at the University of Tennessee Health Science Center with left ventricular hypertrophy and poor feeding after a failed cardiac newborn screen. He had been previously seen at 2 weeks by a cardiologist on follow-up for abnormal critical congenital heart disease screening. Electrocardiogram and echocardiographic studies identified hypertrophic cardiomyopathy. Other examination findings revealed multiple characteristic café-au-lait lesions along with hypotonia and rounded facies. Given his cardiac disease, he was admitted to the hospital, where an evaluation was done for Cushing syndrome, showing elevated cortisol by immunoassay of 38 μg/dL (1.7–14.0 μg/dL, Vitros 5600) after a dexamethasone suppression test and urinary cortisol elevated to 35 μg/dL/24 hours (reference range 3–9 μg/dL/24 hours) (Esoterix; Calabasas, CA). He was started on metyrapone therapy to block synthesis of cortisol. His cortisol improved and was suppressed less than 2 μg/dL. His hypertension and clinical features of Cushing syndrome improved.

Conclusions

This case demonstrates a unique presentation of Cushing syndrome in a young infant. This is the first case to our knowledge showing significant left ventricular hypertrophy resulting from Cushing syndrome identified following a failure on a critical congenital heart disease screen. It highlights the importance of considering of McCune–Albright syndrome in patients with Cushing syndrome, especially if other clinical features are present. Medical therapy can be used to treat Cushing syndrome and can result in improvement in the cardiovascular pathology.

Metyrapone as treatment in the neonatal McCune-Albright syndrome

Objectives To present a case report of succesfully metyrapone treatment of a neonatal patient with McCune-Albrigth syndrome (MAS), a rare disease caused by a genetically mosaic disorder and is characterized by variable hyperfunctional endocrinopathies, bone dysplasia, and café-au-lait spots. Case presentation A preterm newborn was admitted to hospital and she presented difficulty controlling hypertension, café-au-lait spots, and failure to thrive. An abdominal ultrasound and a magnetic resonance showed a high volume of both suprarenal glands. Therefore, MAS was suspected. Laboratory data confirmed adrenocorticotropic hormone-independent Cushing's syndrome with hepatic dysfunction and metyrapone treatment was initiated. A progressive normalization of cortisol levels was achieved despite poor oral tolerance. Conclusion Our case shows that metyrapone is useful in the management of neonatal Cushing's syndrome due to McCune-Albright syndrome.

Neonatal McCune-Albright Syndrome: A Unique Syndromic Profile With an Unfavorable Outcome

Somatic gain‐of‐function mutations of GNAS cause a spectrum of clinical phenotypes, ranging from McCune‐Albright syndrome (MAS) to isolated disease of bone, endocrine glands, and more rarely, other organs. In MAS, a syndrome classically characterized by polyostotic fibrous dysplasia (FD), café‐au‐lait (CAL) skin spots, and precocious puberty, the heterogenity of organ involvement, age of onset, and clinical severity of the disease are thought to reflect the variable size and the random distribution of the mutated cell clone arising from the postzygotic mutation. We report a case of neonatal MAS with hypercortisolism and cholestatic hepatobiliary dysfunction in which bone changes indirectly emanating from the disease genotype, and distinct from FD, led to a fatal outcome. Pulmonary embolism of marrow and bone fragments secondary to rib fractures was the immediate cause of death. Ribs, and all other skeletal segments, were free of changes of typical FD and fractures appeared to be the result of a mild‐to‐moderate degree of osteopenia. The mutated allele was abundant in the adrenal glands and liver, but not in skin, muscle, and fractured ribs, where it could only be demonstrated using a much more sensitive PNA hybridization probe‐based FRET (Förster resonance energy transfer) technique. Histologically, bilateral adrenal hyperplasia and cholestatic disease matched the abundant disease genotype in the adrenals and liver. Based on this case and other sporadic reports, it appears that gain‐of‐function mutations of GNAS underlie a unique syndromic profile in neonates characterized by CAL skin spots, hypercortisolism, hyperthyroidism, hepatic and cardiac dysfunction, and an absence (or latency) of FD, often with a lethal outcome. Taken together, our and previous cases highlight the phenotypic severity and the diagnostic and therapeutic challenges of MAS in neonates. Furthermore, our case specifically points out how secondary bone changes, unrelated to the direct impact of the mutation, may contribute to the unfavorable outcome of very early‐onset MAS. © 2018 The Authors JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Three-Quarters Adrenalectomy for Infantile-Onset Cushing Syndrome due to Bilateral Adrenal Hyperplasia in McCune-Albright Syndrome

BACKGROUND

Bilateral adrenalectomy is performed in cases with infantile-onset Cushing syndrome due to bilateral adrenal hyperplasia in McCune-Albright syndrome (MAS) because severe Cushing syndrome with heart failure and liver dysfunction can have a lethal outcome. This procedure can completely ameliorate hypercortisolism, although lifetime steroid replacement therapy and steps to prevent adrenal crisis are necessary. Recently, the efficacy of unilateral adrenalectomy has been reported in adult cases of bilateral macronodular adrenal hyperplasia, but there is no consensus regarding the appropriate surgical treatment for bilateral adrenal hyperplasia in MAS.

OBJECTIVE

A 6-month-old girl presented with café-au-lait spots, short stature, central obesity, a moon face, and hypertension. Endocrinological tests and imaging studies led to the diagnosis of ACTH-independent Cushing syndrome due to bilateral adrenal hyperplasia induced by MAS. "Three-quarters adrenalectomy", namely right-sided total adrenalectomy and left-sided half adrenalectomy, was carried out. An activating mutation of the GNAS1 gene (p.Arg201Cys) was identified in the adrenal tissues. Since the operation, our patient has been in a state of clinical remission for more than 2 years.

CONCLUSION

Our original surgical intervention, three-quarters adrenalectomy, may be a new treatment option for Cushing syndrome associated with MAS.

Rectal Metyrapone for Treatment of Hypercortisolism in an Infant with McCune-Albright Syndrome

Infantile Cushing syndrome is an infrequent yet potentially fatal manifestation of McCune-Albright syndrome, for which there are few safe treatments available. Ketoconazole is limited by potential hepatotoxicity in this population. Metyrapone may be an effective treatment, but it may not be tolerated when given orally. An infant with McCune-Albright syndrome presented with severe Cushing syndrome. Oral metyrapone resulted in feeding refusal, and ketoconazole caused an increase in liver enzymes; however, she was successfully treated with metyrapone given rectally. The patient avoided a feeding tube, and her serum cortisol concentration was lowered to a safe level. Metyrapone given per rectum may be a safe and effective alternative to oral metyrapone in treating young children with Cushing syndrome.

[Recovery of Cushing syndrome revealing McCune-Albright syndrome]

Cushing syndrome (CS) is a rare feature of McCune-Albright syndrome. Treatments consist of bilateral adrenalectomy followed by lifelong glucocorticoid and mineralocorticoid treatment. However, cases of spontaneous remission of CS have been reported in the literature. We report a case of McCune-Albright syndrome with CS treated with metyrapone for 30 months with prolonged remission after a 12-year follow-up. Adrenalectomy may be avoided in some cases of CS caused by McCune-Albright syndrome. Metyrapone could be a good alternative to surgical treatment.

McCune Albright syndrome and bilateral adrenal hyperplasia: the GNAS mutation may only be present in adrenal tissue

OBJECTIVE

Corticotropin (ACTH)-independent hypercortisolism due to bilateral adrenocortical hyperplasia (BAH) in infancy is an extremely rare condition that is often caused by McCune Albright syndrome (MAS). MAS is caused by an activating mutation of the GNAS gene which leads to increased cyclic (c) adenosine monophosphate (AMP) signaling. Most forms of BAH are linked to increased cAMP signaling. We report the case of an infant with MAS who had BAH.

METHODS

Genomic DNA fragments from blood and adrenal tissue encompassing regions (exons 8 and 9) with the hot spot activating missense GNAS mutations were amplified by classical bidirectional Sanger sequencing.

RESULTS

The infant was found to carry the most common GNAS mutation, in exon 8 (c.602G >A, p. R201H), only in her adrenocortical tissue, despite extensive skin and other findings.

CONCLUSIONS

We conclude that infants with MAS, despite absence of the GNAS activating mutation in blood, may still have significant clinical findings, including ACTH-independent hypercortisolism. Molecular confirmation of the diagnosis should be sought at the tissue level in these patients.

Primary bimorphic adrenocortical disease: cause of hypercortisolism in McCune-Albright syndrome

McCune-Albright syndrome (polyostotic fibrous dysplasia, café-au-lait skin spots, and precocious puberty) is a genetically mosaic disorder with populations of mutant and normal cells in affected organs. Cushing syndrome, a rare feature of the condition, usually affects infants and is the result of corticotropin-independent primary bilateral adrenal disease, usually interpreted as nodular adrenocortical hyperplasia. In this study of 9 patients with Cushing syndrome and McCune-Albright syndrome, light microscopy revealed a characteristic bimorphic pattern of diffuse and nodular hyperplasia and a distinctive form of cortical atrophy with apparent zona glomerulosa hyperplasia in 8 patients, all very young. The pattern could be explained by the presence of a mosaic distribution of mutant and normal cells in the adrenal glands. The findings are different from those in inherited or other forms of genetically caused Cushing syndrome. The ninth patient, aged 17 years, had an adrenal adenoma and diffuse cortical hyperplasia in each adrenal gland.

Unilateral adrenalectomy can be an alternative therapy for infantile onset Cushing' s syndrome caused by ACTH-independent macronodular adrenal hyperplasia with McCune-Albright syndrome

We report herein the case of a 1-year-old boy with McCune-Albright syndrome (MAS) who presented with infantile-onset Cushing' s syndrome caused by ACTH independent macronodular adrenal hyperplasia (AIMAH). Abdominal CT, MRI, and adrenal scintigraphy with (131)I-adosterol identified bilateral adrenal involvement with the left adrenal gland being larger and functionally more active. Unilateral adrenalectomy of the left gland was performed and ameliorated many clinical symptoms, such as Cushingoid appearance and height restriction, and it also normalized many endocrinological data, such as diurnal rhythms of ACTH and cortisol, ACTH and cortisol responses to CRH, and urinary 24 hr free cortisol. Glucocorticoid was replaced for the first 1 year and 6 months after the operation. One adrenal crisis episode occurred at 3 weeks after the operation, but none have occurred since. These results suggest that unilateral adrenalectomy of the larger gland can be an alternative therapy for infantile onset Cushing' s syndrome caused by AIMAH with MAS, when asymmetric involvement is evident and the smaller gland is not markedly enlarged.