Endocrine Abstracts

Background: Addison’s disease is an autoimmune condition which affects approximately 1 in 14,000 people in the UK. It is caused by destruction of the adrenal cortex leading to insufficient production of cortisol and aldosterone. Dent disease is caused by a defect in a voltage gated chloride ion channel due to a mutation in CLCN5 gene. It is characterised by renal tubular dysfunction, including proteinuria, hypercalciuria, nephrocalcinosis, and nephrolithiasis. Dent disease is considered a rare disease with prevalence estimated between 1 in 400,000 and 1 in 1,000,000.

Clinical Case: 4-year-old male presented to hospital whilst on holiday in Turkey with a 3-day history of vomiting and lethargy. He was found to be in circulatory shock with hypoglycaemia, hyponatraemia and hypotension. The working diagnosis was a suspected underlying adrenal insufficiency; he was incidentally found to have bilateral nephrocalcinosis on renal ultrasound scan during his admission. Following discharge from PICU he was admitted to his local hospital. A short synacthen test confirmed adrenal insufficiency and adrenal antibodies were positive confirming the diagnosis of Addison’s Disease. He was commenced on hydrocortisone and fludrocortisone as well as sodium supplements for hyponatraemia. 6 months after his initial presentation the patient was admitted with lethargy and fever and was found to be COVID positive. Concerns were raised during this admission due to worsening renal function, hypokalaemia, proteinuria and his renin being significantly elevated (1,928.0 mU/l). He had normal renal function prior to his initial presentation. There were significant concerns from the Endocrine Team that despite initiating treatment for Addison’s, the patient required increasing sodium supplements, and a renal pathology or unifying genetic diagnosis was suspected in addition to his diagnosis of Addison’s. Further renal evaluation showed Glomerular Filtration Rate 54 suggestive of CKD stage 3, this indicated significant renal deterioration over 1 year. Genetics confirmed a secondary diagnosis of Dent’s Disease, 19 months after his initial presentation with Addisonian crisis and nephrocalcinosis.

Conclusion: This case highlights the importance of perseverance in looking for additional diagnoses when the initial one does not encompass the entirety of the complex presentation.