ACTA ENDOCRINOLOGICA (BUC)

Background. Idiopathic hypercalciuria is a risk factor for nephrolithiasis. Both renal stones and hypercalciuria are associated with lower bone mineral density (BMD), but the relationship between these modifications is not completely understood. Aims. To evaluate some metabolic particularities possibly related to relapsing nephrolithiasis (RN) in young male patients. Methods. We performed a crosssectional study including a group of 30 young male patients with RN and a group of 30 healthy, age and BMI (body mass index) matched controls (CTR). We evaluated calcium and phosphate metabolism, bone remodeling markers alkaline phosphatase (AP) and osteocalcin in serum and 24-hour urine samples, and lumbar and hip BMD. Results. We observed higher values of serum calcium (P<0.05) and 24 hour urinary calcium (P<0.001) in the RN group. Parathyroid hormone (PTH) and AP were also higher in the RN group (P<0.01), whereas serum 25OH-D3 was lower (P<0.01). BMD, T and Z scores were lower in the RN group in both the lumbar (P<0.01) and hip (P<0.05) regions. Conclusions. Young male patients with hypercalciuric RN have lower BMD and higher bone turnover. Higher PTH levels related to vitamin D deficiency may contribute to bone demineralization in certain cases.

Purpose. To correlate the volume of parathyroid adenomas with the hormonal and metabolic profile at patients diagnosed with primary hyperparathyroidism (pHPTH). Patients and Methods. Cross-sectional multicentric study, enrolling 52 patients with pHPTH from two medical institutions. Serum calcium and PTH were evaluated in all patients before surgery, whereas 25OHD3 was measured only in the 33 patients recruited form one medical unit. The volume of parathyroid adenoma was measured by using the formula of a rotating ellipsoid. Results. We observed a significant correlation of the volume of parathyroid adenomas with PTH at patients from the two units and in the whole group (p < 0.0001), but not with serum calcium (p = 0.494). Twenty-five out of the 33 patients at whom 25OHD3 was measured had levels in the range of deficiency. 25OHD3 was not correlated with PTH or calcium levels, but was negatively correlated to the adenoma volume and positively to the PTH/volume ratio (p = 0.041 and p = 0.048, respectively). Conclusions. The volume of parathyroid adenoma seems to be related to preoperative PTH and 25OHD3, but not to calcium level. Vitamin D deficiency is frequently found at patients with pHPTH and may contribute to particular disease profiles, including larger parathyroid adenomas.

Purpose. We checked the advantage of intraoperative quick PTH (iqPTH) for improving cure rate of patients operated for primary hyperparathyroidism (PHPTH) by using minimally invasive surgery. Methods. We compared two groups of patients diagnosed with PHPTH by preoperatory localized single parathyroid adenoma (PA) submitted to minimal invasive surgery with histological confirmation. Patients from a control group (C) were operated without measuring intraoperative PTH, whereas in the second group iqPTH was assessed after adenoma excision and before wound suture. When quick PTH dropped less than 50%, conversion to open surgery and bilateral exploration followed. Results. Six of the 40 patients from the C group (15%) had persistently elevated postoperative PTH, needing reintervention. High intraoperative PTH levels persisted in two of the 13 patients from the iqPTH group (15.4%), but conversion to open surgery allowed localizing and excision of preoperatory undetected supplementary PA, increasing success rate to 100% (p < 0.05). Conclusions. Assessment of iqPTH in PHPTH before wound suture provides reliable confirmation of accurate adenoma removal. Persistence of high PTH levels after adenoma removal suggests multiple gland disease and requires conversion to bilateral neck exploration in order to increase cure rate.