Urolithiasis : Screening for Hyperparathyroidism is Essential

ABSTRACT

Thirty two patients having complex renal stones in the age group of 10-60 years were studied to detect hyperparathyroidism (HPT). The clinical diagnosis varied from bilateral renal stones in 20 (62.5%),2 (6.22%) had large unilateral stone, 2 (6.622%) had recurrent bilateral renal calculi and 4 (12.5%) had unilateral recurrent calculi. Serum calcium was raised (> 10.5 mg%) in 9 (20%) cases. Parathyroid hormone (PTH) was found raised, ranging from 80-1330 pg/ml (N 16-65 pg/ml) in 9 (28%) cases out of 32. Hypercalcemia (> 105 gm %) was found in 7 out of 9 cases of HPT whereas in other 2 cases it was normal (8.9 mg %) and upper normal (1 O.3mg %) respectively. Hypercalciuria (>250mgl24 hrs) was found in 5 patient ofHPT and rest 3 patients had normal levels. Serum phosphate was found in the range of 1.4-7.1mg% (N 2.5-6.8mg %) in 30 cases, on patient had < 2.5mg % and one patient had >6.8mg %. One patient with hypercalcemia had both urinary calcium as well as PTH normal. Dual subtraction scan (thallium and technetium) was done in all 9 patients with raised PTH. Scan was positive with adenoma in 4 (12.5%) cases. One patient 15 years old girl with a positive scan had both serum calcium and 24 hrs. urinary calcium levels normal with raised PTH (90-100 pg/ml). Scan reported doubtful hyperplasia in one (3.12%) patient out of 32. This patient, a multiple stone passer had normal serum calcium as well as 24 hrs. urinary calcium with raised PTH (99.60) pg/ml). 4 cases (12.5%) had a normal scan. Four (12.5%) cases with positive scan underwent parathyroidectomy (PTX). Serum calcium and PTH concentration dropped to normal levels in the postoperative period. Rest of the cases of HPT with normal and doubtful scans are under follow up.