An Overlooked Manifestation of Hypercortisolism: Cerebral Cortical Atrophy and Challenges in Identifying the Etiology of Hypercortisolism - A Report of 2 Pediatric Cases.

INTRODUCTION: Endogenous Cushing's syndrome (CS) is a rare, severe disease that can cause multiple systemic involvements and behavioral problems due to excessive cortisol production. Structural changes can be noted in the brain magnetic resonance imaging (MRI) scans of these cases. CASES: A 9-year-old girl and a 13-year-old boy were admitted with hypercortisolism. In the female patient, altered consciousness was prominent along with cerebral and cerebellar brain atrophy, and findings indicating posterior reversible encephalopathy syndrome were detected in the brain MRI. Although the male patient's neurological examination was normal, significant cerebral atrophy was seen in the brain MRI. Case 1 was diagnosed as having ectopic ACTH syndrome (EAS) due to a thymic carcinoid tumor. Case 2 underwent a pulmonary lobectomy upon detection of a bronchial lesion in the Ga-68 DOTATATE PET/CT scan while being examined for EAS due to a lack of suppression in the high-dose dexamethasone suppression test. However, hypercortisolism persisted despite the removal of the bronchial lesion, and subsequently, a diagnosis of Cushing's disease was established following bilateral inferior petrosal sinus sampling. DISCUSSION: Endogenous hypercortisolism may cause brain atrophy of varying severity. The central nervous system findings can be overlooked in children with CS. More comprehensive studies are needed to better understand the behavioral changes caused by the effects on the brain and to evaluate whether these changes are reversible. In addition, identifying the source of hypercortisolism can be difficult due to a lack of experience related to the rarity of the disease in children.

Clinical and genetic spectrum from a prototype of ciliopathy: Joubert syndrome.

OBJECTIVE: Joubert syndrome is a neurodevelopmental disorder with a distinctive hindbrain malformation called molar tooth sign, causing motor and cognitive impairments. More than 40 genes have been associated with Joubert syndrome. We aim to describe a group of Joubert syndrome patients clinically and genetically emphasizing organ involvement. METHODS: We retrospectively collected clinical information and molecular diagnosis data of 22 patients with Joubert syndrome from multiple facilities. Clinical exome or whole-exome sequencing were performed to identify causal variations in genes. RESULTS: The most common variants were in the CPLANE1, CEP290, and TMEM67 genes, and other causative genes were AHI1, ARMC9, CEP41, CSPP1, HYLS1, KATNIP, KIAA0586, KIF7, RPGRIP1L, including some previously unreported variants in these genes. Multi-systemic organ involvement was observed in nine (40%) patients, with the eye being the most common, including Leber's congenital amaurosis, ptosis, and optic nerve coloboma. Portal hypertension and esophageal varices as liver and polycystic kidney disease and nephronophthisis as kidney involvement was encountered in our patients. The HYLS1 gene, which commonly causes hydrolethalus syndrome 1, was also associated with Joubert syndrome in one of our patients. A mild phenotype with hypophyseal hormone deficiencies without the classical molar tooth sign was observed with compound heterozygous and likely pathogenic variants not reported before in the KATNIP gene. CONCLUSION: Some rare variants that display prominent genetic heterogeneity with variable severity are first reported in our patients. In our study of 22 Joubert syndrome patients, CPLANE1 is the most affected gene, and Joubert syndrome as a ciliopathy is possible without a classical molar tooth sign, like in the KATNIP gene-affected patients.