Failure to Thrive in the Context of Carney Complex

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.

Liver findings in patients with Carney complex, germline PRKAR1A pathogenic variants, and link to cardiac myxomas

This study aimed to evaluate liver involvement in patients with Carney complex (CNC) based on a large cohort and to analyze any germline PRKAR1A genotype-phenotype association of liver disease. The study included 83 patients with CNC, followed between 1995 and 2018 at a tertiary research center. We reviewed liver images, recorded types and number of lesions and analyzed per genotype: all patients were sequenced for the PRKAR1A gene. A total of 29/83 patients (24.0%) had liver radiological findings. Patients with liver lesion had a significantly higher rate of pathogenic variants detected in the PRKAR1A gene (72.4 vs 38.9%, P = 0.005, respectively). Patients with a pathogenic variant detected on germline PRKAR1A analysis had a higher risk for having a liver lesion compared with patients with wild-type (WT) PRKAR1A alleles (21/42 (50.0%) vs 8/41 (19.5%), respectively, P = 0.004). Among patients with liver lesions, those with a nonsense PRKAR1A pathogenic-variant had more liver lesions (7/7) than among those with other pathogenic-variant types (8/22, P = 0.001). In multivariable analysis, detection of liver lesion(s) was associated with an odds ratio of 5.2 for cardiac myxomas (95% CI 1.55-17.49, P = 0.008). In conclusion, patients with CNC, particularly with a PRKAR1A pathogenic variant, have a higher rate of liver lesions. Additionally, liver lesions are associated with a high risk for cardiac myxomas in this population.

65 YEARS OF THE DOUBLE HELIX: Endocrine tumour syndromes in children and adolescents

As medicine is poised to be transformed by incorporating genetic data in its daily practice, it is essential that clinicians familiarise themselves with the information that is now available from more than 50 years of genetic discoveries that continue unabated and increase by the day. Endocrinology has always stood at the forefront of what is called today 'precision medicine': genetic disorders of the pituitary and the adrenal glands were among the first to be molecularly elucidated in the 1980s. The discovery of two endocrine-related genes, GNAS and RET, both identified in the late 1980s, contributed greatly in the understanding of cancer and its progression. The use of RET mutation testing for the management of medullary thyroid cancer was among the first and one of most successful applications of genetics in informing clinical decisions in an individualised manner, in this case by preventing cancer or guiding the choice of tyrosine kinase inhibitors in cancer treatment. New information emerges every day in the genetics or system biology of endocrine disorders. This review goes over most of these discoveries and the known endocrine tumour syndromes. We cover key genetic developments for each disease and provide information that can be used by the clinician in daily practice.