Use of intranodular parathyroid hormone values obtained by fine needle aspiration as a predictive factor of postoperative hypoparathyroidism

Abstract

To analyze if parathyroid hormone (PTH) washout levels can be considered a predictive factor of postoperative hypoparathyroidism and determine its importance relative to other features already known as intraoperative PTH, Ca and PTH preoperative, and others. Method: Of the 157 patients to whom a fine needle aspiration (FNA) biopsy with intranodular parathyroid hormone level measurement was performed (washout PTH) 37 who underwent surgery were studied. 15 variables were taken into account when selecting patients for this study: age, gender, evolution length, size, associated thyroid surgery, preoperative treatment with calcimimetics, presence of renal lithiasis, bone densitometry alterations, creatine clearance, preoperative calcium and PTH levels, PTH scores obtained by fine needle aspiration, intraoperative PTH decrease, postoperative calcium levels and tumor malignancy. We compare the nominal values, using the Chi squared or the exact Fisher test, where p <0.05 was considered statistically significant and perform a logistic regression analysis. Results: The use of mimetics prior to surgery, the preoperative PTH level above 88 pg/dl, the preoperative calcium above 12 mg/dl, washout PTH above 2700 pg/dl, intraoperative PTH level decrease below 15 pg/dl, and postoperative calcium levels under 8.5 mg/dl were all independently significant variables in the univariant analysis (p <0.05) in order to establish an early postoperative hypoparathyroidism. The rest of the variables were not statistically significant. Conclusion: The PTH washout levels can predict the appearance of postoperative hypoparathyroidism. This factor must be taken into account during the study and follow-up to identify possible complications and establish an adequate treatment on time.