case_images: PMC11043563_01
case_images: Timeline summarization of the patient's clinical course. Asymptomatic hypercalcaemia was incidentally found in 2019. The same year, primary hyperparathyroidism (PHPT) was diagnosed, and the presence of suspected lesion was confirmed in the imaging studies. The patient underwent parathyroidectomy which led to normocaicaemia. After 10 months, vitamin D supplementation was initiated due to deficiency. In 2022, biochemical tests revealed recurrence of hypercalcaemia with suppressed PTH concentration. After the exclusion of the common causes of PTH-independent hypercalceamia, the presence of two heterozygous loss-of-function mutations in the CYP24A1 gene was confirmed in Next-Generation Sequencing (NGS). After discontinuation of vitamin D supplementation, calcium and PTH concentrations normalized. PTH-parathormone; MIBI -technetium-99m-sestamibi scintigraphy; CYP24A1- cytochrome P450 family 24 subfamily a member 1.
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case_images: PMC11043563_01_fendo-15-1355916-g002.jpg
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case_images: Table 1 ;  Figure 2 ). The patient did not attend her follow-up appointments for two years. However, blood tests revealed PTH suppression with elevated 1,25(OH)2D3 concentrations ( Table 1 ;  Figure 2 ).