Patient with adrenal insufficiency due to a de novo mutation in the NR0B1 gene.

Objectives: Congenital X-linked adrenal hypoplasia is a rare disease with a known genetic basis characterized by adrenal insufficiency, hypogonadotropic hypogonadism, and a wide variety of clinical manifestations. Case presentation: We present the case of a 26-day old male newborn with symptoms consistent with adrenal insufficiency, hyponatremia, and hyperkalemia. Following NaCl and fludrocortisone supplementation, the patient remained clinically stable. 17-OH-progesterone testing excluded congenital adrenal hyperplasia. The rest of hormones were within normal limits, except for adrenocorticotropic hormone (ACTH), which was significantly elevated, and aldosterone, which was below the reference value. Further testing included very long chain fatty acids to exclude adrenoleukodystrophy, the CYP11B2 gene (aldosterone synthase), and an MRI to screen for other morphological abnormalities. All tests yielded normal results. Finally, after cortisol deficiency was detected, expanded genetic testing revealed a mutation in the NR0B1 gene, which led to a diagnosis of congenital adrenal hypoplasia. Conclusions: Diagnosis of congenital adrenal hypoplasia is challenging due to the heterogeneity of both clinical manifestations and laboratory abnormalities. As a result, diagnosis requires close monitoring and genetic testing.

Harmonization of indirect reference intervals calculation by the Bhattacharya method.

OBJECTIVES: The aim of this study was to harmonize the criteria for the Bhattacharya indirect method Microsoft Excel Spreadsheet for reference intervals calculation to reduce between-user variability and use these criteria to calculate and evaluate reference intervals for eight analytes in two different years. METHODS: Anonymized laboratory test results from outpatients were extracted from January 1st 2018 to December 31st 2019. To assure data quality, we examined the monthly results from an external quality control program. Reference intervals were determined by the Bhattacharya method with the St Vincent's hospital Spreadsheet firstly using original criteria and then using additional harmonized criteria defined in this study. Consensus reference intervals using the additional harmonized criteria were calculated as the mean of four users' lower and upper reference interval results. To further test the operation criteria and robustness of the obtained reference intervals, an external user validated the Spreadsheet procedure. RESULTS: The extracted test results for all selected laboratory tests fulfilled the quality criteria and were included in the present study. Differences between users in calculated reference intervals were frequent when using the Spreadsheet. Therefore, additional criteria for the Spreadsheet were proposed and applied by independent users, such as: to set central bin as the mean of all the data, bin size as small as possible, at least three consecutive bins and a high proportion of bins within the curve. CONCLUSIONS: The proposed criteria contributed to the harmonization of reference interval calculation between users of the Bhattacharya indirect method Spreadsheet.