7090 The Largest Study on Asymptomatic Primary Hyperparathyroidism (APHPT) Conducted at the Tertiary Care Riga East Clinical University Hospital (RECUH)— Three Years of Data

Abstract

Abstract Disclosure: D. Stūrīte: None. I. Rasa: None. Background: Primary hyperparathyroidism (PHPT) is the third most common endocrine disorder and a leading cause of hypercalcemia in the outpatient setting. The study aimed to assess the characteristics, management and outcomes of pts with APHPT. Methods: A retrospective analysis of data from 168 pts with APHPT, evaluated at RECUH from January 2021 to November 2023 was conducted. Information obtained included medical records, laboratory data, imaging results, surgical protocols, histopathology data. Statistical analysis was performed using IBM SPSS 29.0. Results: From the 168 pts (mean age: 63.7±11.8 years), 86.3% (n=145) were females. Predominantly, 67.3% (n=113) exhibited mild hypercalcemia (2.6-3.0mmol/L), while 22.6% (n=38) had moderate hypercalcemia (3.0-3.49mmol/L), and 4.8% (n=8) -severe hypercalcemia (≥3.5mmol/L). 5.3% (n=9) had normocalcaemic PHPT. The mean preoperative maximal calcium level was 2.9±0.3mmol/L, iPTH level - 247.6±224.9pg/mL, minimal phosphorus - 1.3±6.7mmol/L and 25-OH vitamin D level - 28.3±14.7ng/mL. The mean preoperative eGFR was 90.6±28.2 ml/min/1.73m2, creatinine - 72.5±23.9μmol/L. Parathyroid adenoma sizes ranged from 0.3x0.4cm to 5.3x3.7cm. Calcium levels positively correlated with adenoma cross-sectional area (ρ=0.187, p=0.029) and maximal adenoma dimension (ρ=0.215, p=0.011). Ultrasonography convincingly detected parathyroid adenomas in 63.9% (107/168), SPECT/CT - 68.4% (52/76), 99mTc-sestamibi scintigraphy - 65.6% (61/93), 3D-CT - 70.6% (24/34), contrast-enhanced ultrasonography - 84% (21/25) and MRI in - 40% (2/5) cases. 12.5% (n=21) pts had unlocated parathyroid adenoma. 34.5% (n=58) of pts had osteoporosis, 47.6% (n=80) osteopenia, 12.5% (n=21) had a history of osteoporotic fracture, 17.3% (n=29) had gallstones and 22.0% (n=37) - kidney stones. 80.4% (n=135) of pts had thyroid nodules, 48.2% (n=81) - nontoxic goitre, 24.4% (n=31) - autoimmune thyroiditis, 41.7% (n=70) - hypertension, 10.5% (n=18) - type 2 diabetes. 18.5% (n=31) pts were found to have a diagnosis of malignancy. 61.9% (n=104) of pts underwent parathyroidectomy. Histopathology and radiologic imaging revealed single parathyroid adenoma in 95.2% (n=99), double parathyroid adenomas in 1.9% (n=2), parathyroid hyperplasia in 2.9% (n=3) and parathyroid carcinoma in 1.9% (n=2) pts. The mean maximal postoperative calcium level (n=103) was 2.4±0.1mmol/L, iPTH (n=101) - 63.5±27.7pg/mL, 25-OH vitamin D - 41.5±13.3ng/mL, and the mean minimal phosphorus (n=56) - 1.1±0.2mmol/L. Conclusions: APHPT remains frequently encountered and often showcases bone manifestations. It's crucial to consider the diverse clinical manifestations and associated conditions in patients with APHPT. Presentation: 6/2/2024