The Feasibility Study Of PTH Rapid Detection In Predicting Postoperative Hypoparathyroidism

Objectives:To explore the accuracy of two rapid detection methods of parathyroid hormone(PTH),colloidal gold immunochromatographic assay(CGIA)and fluorescence immunochromatography assay(FIA),for real-time diagnosis of postoperative hypoparathyroidism;To explore the feasibility of rapid detection of PTH in serum and drainage fluid after thyroid surgery to predict hypothyroidism in patients 6 months after surgery.Methods: The data of 139 patients with thyroid diseases requiring surgical treatment in the First Affiliated Hospital of Kunming Medical University from November 2021 to August 2022 were collected,including the patient’s sex,age,body mass index(BMI),hand type(thyroidectomy range,neck lymph node dissection range,parathyroid autotransplantation and retention),serum ionic calcium,25-OH-vitamin D,PTH Whether it is accompanied by Hashimoto’s thyroiditis(HT),whether there is extraglandular invasion,and whether the parathyroid gland is accidentally detected.The patients’ peripheral blood serum and postoperative drainage fluid were collected before operation,2h,4h and 24 h after operation,respectively.The PTH levels were measured by CGIA,FIA and radioimmunoassay(RIA).At the same time,the percentage of decrease in serum PTH(s PTH)at 2h,4h and 24 h after operation compared with that before operation,and the level of decrease in drainage fluid PTH(d PTH)compared with that at 2h after operation were calculated,and the symptoms of parathyroidism and calcium supplementation were recorded.Follow-up was carried out 6 months after the operation to record the relevant symptoms and serum PTH and ionic calcium levels.The data were analyzed using SPSS 25.0software as follows:(1)The quantitative data were tested for normal distribution by single-sample K-S test.The non-normal distribution was represented by the median(M)and the upper and lower quartiles(P25,P75)and the non-parametric rank sum test was adopted.The normal distribution was represented by the mean ± standard deviation (?)(± s)and the t-test was adopted;The counting data is expressed and used in frequency and percentage χ 2 Inspection.Inspection level α=0.05.(2)The reliability of CGIA and FIA in real-time diagnosis of Poh was evaluated by using Kappa analysis,and the best cut-off value was obtained by drawing the receiver operating characteristic curve.(3)Single factor analysis was carried out for patients with hypothyroidism and normal parathyroidism to screen out potential predictors of postoperative hypothyroidism,and then the ROC curve was drawn and the best cutoff value of each index was calculated.When P<0.05,the difference was considered statistically significant.Results: A total of 139 patients who underwent thyroid surgery for thyroid diseases were included in this study,and 5 patients(3.60%)had POH at 6 months after surgery.The s PTH and d PTH measured by three methods before operation,2h after operation,4h after operation and 24 h after operation showed a general downward trend.The ROC curve analysis shows that the AUC of s PTH-RIA,s PTH-CGIA,and s PTH-FIA for real-time diagnosis of POH are 0.999(P<0.001),0.858(P<0.001),0.756(P<0.001),respectively.After calculating the Youden index of each variable,the best cutoff values of s PTH-RIA,s PTH-CGIA,and s PTH-FIA for diagnosis of POH are 11.85pg/ml(sensitivity 1.00,specificity 0.991),15.45pg/ml(sensitivity 0.719,specificity 0.856)32.03pg/ml(sensitivity 0.789,specificity 0.577).Through univariate analysis,nine predictive factors(OR>1,P<0.05)of POH in 6months were selected,including △ s PTH%-RIA at 2 hours after operation,△s PTH%-FIA at 2 hours after operation,△ s PTH%-RIA at 4 hours after operation,△ s PTH%-FIA at 4 hours after operation and △ s PTH%-RIA,△s PTH%-FIA,△d PTH%-RIA,△ d PTH%-CGIA,△d PTH%-FIA at 24 hours after operation,and the best cutoff values were 95.5%(sensitivity 100%,specificity85.1%),90%(sensitivity 100%,specificity 61.9%)97.5%(sensitivity 100%,specificity 81.3%),90%(sensitivity 100%,specificity 67.9%),99.5%(sensitivity100%,specificity 94%),88.5%(sensitivity 100%,specificity 59.7%),84%(sensitivity 100%,specificity 80.6%),47.5%(sensitivity 100%,specificity 76.1%),66.5%(sensitivity 100%,specificity 91.0%).Conclusions: The colloidal gold method and immunofluorescence method can make rapid and real-time diagnosis of POH,and provide convenience and give full play to the advantages of timely detection of s PTH during or within 24 hours after operation.△ s PTH%-RIA,△ s PTH%-FIA at 2 hours after operation;△ s PTH%-RIA,△ s PTH%-FIA at 4 hours after operation and △ s PTH%-RIA,△ s PTH%-FIA at 24 hours after operation are potential predictive indicators of POH at 6 months after operation,which can be used to predict the occurrence of POH at 6 months after operation and provide a basis for formulating long-term treatment plans.RIA,CGIA and FIA can be used to predict the occurrence of POH in 6 months after operation,and avoid the damage and inconvenience of blood collection.