저칼슘혈증 예측지표로서 부갑상선 호르몬 검사반응시간에 따른 유용성

The Usefulness According to the Incubation Time of PTH as Prediction Index of Hypocalcemia

Purpose: PTH (parathyroid hormone) level is a useful index for prediction of hypocalcemia after thyroidectomy. The fast results are required for an early diagnosis of hypocalcemia. In this study, we evaluated the PTH change according to incubation time, and investigated the usefulness of hypocalcemia diagnosis of PTH results in early incubation time. Materials and Methods: The subjects were 131 patients who had taken the PTH test from July to August in 2009. All experiments were used IRMA method. PTH value were evaluated with the correlation between precision (10 times repeat) and recovery rate and at 0.5, 3, 6 and 18±2 (below overnight) hours following incubation time. Data analysis was investigated with relationship of the sensitivity, specificity, PPV (positive predictive value) and accuracy. Results: The correlation was time-dependent with levels reaching R²=0.987 at 0.5 hours, R²=0.993 at 3 hours and R²=0.996 at 6 hours compare to overnight levels. The precision (%CV±SD) were 15.92±15.54 at 0.5 hours, 6.91±7.38 at 3 hours, 4.30±4.69 at 6 hours and 4.59±2.59 at overnight. The recovery rate (%Mean±SD) were 96.8±5.44 at 0.5 hours, 102.6±4.35 at 3 hours, 100.7±2.56 at 6 hours and 102.2±5.98 at overnight. When 15 pg/㎖ of overnight density was set up as criteria, we measured the sensitivity, specificity and PPV, accuracy at 0.5, 3, 6 hours. The sensitivity was shown to 97.5% at all times. The specificity was 96.0% at 0.5 hours, 100% at 3 hours and 92.3% at 6 hours for control, respectively. The PPV was 86.6% at 0.5 hours, 100% at 3 hours and 92.8% at 6 hours. The accuracy was shown to 84.7% at 0.5 hours, 97.5% at 3 hours and 90.6% at 6 hours. These data were accompanied by a corresponding PTH value of overnight incubation time, which significantly correlated with early time results. Conclusion: The values of PTH at 3 hours has favorable the rate of concordance of 94.1% and may be useful for prediction of hypocalcemia, and it responses to overnight incubation PTH values. Therefore, This method may be an attractive alternative to proper treatment to stop symptom revelation by giving a calcium agent to the patient.