Primary Hyperparathyroidism in a Predominantly Vitamin D Deficient Population: A Single Center Experience

Abstract

Primary hyperparathyroidism (PHPT) has a variable clinical presentation. Symptomatic PHPT continues to be the predominant form of the disease in the Indian subcontinent, but a decreasing trend of symptomatic cases is observed, and increasing numbers of asymptomatic cases are now being diagnosed. In these cases, 25-hydroxy vitamin D [25(OH)D] shows no correlation with the serum levels of calcium and intact parathyroid hormone (iPTH). To study the characteristics of patients with hyperparathyroidism and the relationship of 25(OH)D with the levels of calcium and i PTH. A study was conducted with 78 consecutive patients diagnosed from 1996 to 2018 with PHPT, in whom the vitamin D status was investigated preoperatively. Of the 78 study subjects, 67 (85.7%) were females and 11 (14.2%) were males. Their age ranged from 16 to 70 years. Nephrolithiasis was the single most common presentation (44.3%) followed by bone pain (42.6%). Only 5% of the subjects were asymptomatic, with a decreasing trend of symptomatic cases and increasing number of asymptomatic cases with time. Their mean serum calcium level was 11.5±1.0 mg/dl, mean serum iPTH level 377±386.1 pg/ml, mean 25(OH)D level 37.2±58.1 ng/ml, while 48% of the patients were vitamin D deficient. The serum levels of 25(OH)D showed no correlation with serum calcium and iPTH levels, whereas it showed a negative correlation with tumor size. Neck ultrasound (US) was indicative of parathyroid pathology and laterality in 89.8% and showed the exact site of the parathyroid pathology in 63.3%. Technetium99sestamibi (MIBI) scan was indicative of parathyroid pathology (side accuracy) in 92.5% and showed the exact site in 85.7% of patients. A single parathyroid gland was involved in 90% of study subjects, double glands in 8% and multiple glands/hyper-plasia in 1.6%. Histopathological examination showed parathyroid adenoma in 86.3% and parathyroid hyperplasia in 7.8%. Temporary post-operative hypocalcemia was detected in 36% of the patients; the cure rate was 98.4%, without any operative mortality. Primary hyperparathyroidism continues to be mainly a symptomatic disease in the Kashmir Valley. There is a decreasing trend of symptomatic cases and an increasing number of asymptomatic cases with time. The level of 25(OH)D has no correlation with serum calcium, iPTH or tumor size in these patients.