Post Thyroidectomy Assessment of Intact Parathyroid Hormone for Early Prediction of Hypocalcaemia

Background: As the half-life of intact parathyroid hormone (iPTH) is very low, it reflects parathyroid insufficiency within minutes to hours after total thyroidectomy. Therefore, iPTH level assessment in the postoperative period can be used to predict the development of hypocalcaemia. The optimal time point to measure serum iPTH is important for the accurate prediction of hypocalcaemia. Aim: This paper aims to evaluate the ability of iPTH as an early predictive marker of hypocalcaemia and determine which time iPTH is more able to predict postoperative hypocalcaemia. Method: This prospective observational study was conducted in the Department of Otolaryngology-Head & Neck Surgery, BSMMU, Dhaka, from July 2020 to December 2021, with 67 patients who underwent total thyroidectomy. iPTH levels were measured on the day before the operation and at 1 hour, 4 hours, and 24 hours after the operation. S.calcium levels were measured on the day before the operation and 1st postoperative day. All the data were compiled and sorted properly and were analyzed statistically. Results: Postoperative hypocalcaemia developed in 18 cases, with an incidence of 26.9%. Pearson correlation showed a significant correlation between postoperative iPTH at 1 hr, 4 h, and 24 hr with 1st postoperative calcium value. The Receiver operating characteristic (ROC) curve was processed for the postoperative iPTH at 1 hr, 4 h, and 24 hr. The sensitivity, specificity, cut-off value, and mean AUC found 93.9%, 94.4%, ≤14.0, 0.988;95.9%, 94.4%, ≤09.5, 0.993 and 91.8%, 94.4%, ≤11.0, 0.993 respectively. Conclusion: iPTH can be used as an early predictor of post-thy-roidectomy hypocalcaemia. 4 hr iPTH showed more sensitivity and specificity for a cut-off value near the laboratory reference range.

Effects of Lanthanum Carbonate on Vascular Calcification in Elderly Maintenance Hemodialysis Patients

Summary： The effect of lanthanum carbonate on abdominal aortic calcification （AAC） in the elderly maintenance hemodialysis （MHD） patients was investigated. Fifty-four cases subjected to routine MHD complicated with skin pruritus admitted to our hospital were selected and randomly divided into case group （n=28） and control group （n=26）. The control group was given routine MHD alone. The case group was given lanthanum carbonate additionally on the basis of routine MHD. The changes of itching degrees at first and third month, and serum calcium, phosphorus, calcium-phosphorus products, intact parathyroid hormone （iPTH） levels and AAC scores at third month after treatments were compared be- tween the two groups. The correlation between calcium-phosphorus products and AAC scores was also analyzed. There was no significant difference in the baseline of blood urea nitrogen （BUN）, serum creatinine （Scr）, uric acid, albumin, hemoglobin, C reactive protein （CRP）, low density lipoprotein （LDL）, high density lipoprotein （HDL）, triglyceride, total cholesterol between case group and control group （P〉0.05 for all）. There was also no significant difference in the baseline itching scores between the case group and the control group （P〉0.05）. At 1st and 3rd month after treatment, the itching scores in the case group were 14.2±3.2 and 10.5±2.3, respectively, which were significantly lower than the baseline and those in the control group （P〈0.05 for all）. At 1 st and 3rd month after treatment, the itching scores in the control group were 23.6v5.9 and 24.8±6.3, respectively, which were significantly higher than the baseline （P〈0.05）. There was no significant difference in the baseline of serum calcium, phos- phorus, calcium-phosphorus products, iPTH levels between the case group and control group （P〉0.05）. At 3rd month after treatment, serum phosphorus, calcium-phosphorus products and iPTH levels in the case group were decreased significantly as compared with the baseline （P〈0.05）, and the serum calcium, phosphorus, calcium-phosphorus products, and iPTH levels were statistically decreased as compared with those in the control group （P〈0.05）. The AAC scores showed statistically significant difference between the case group and the control group （P〈0.05）. The serum phosphorus and AAC scores showed a positive correlation in both two groups. It was suggested that the administration of lanthanum carbon- ate in the elderly MHD patients can effectively relieve itching, and simultaneously reduce serum phos- phorus and iPTH levels, resulting in the attenuation of vascular calcification.