Related Experiment Video
Updated: Feb 16, 2026

A Two-Step Method for Percutaneous Transhepatic Choledochoscopic Lithotomy
Published on: September 13, 2022
Is the Homocysteine Level a Good Predictive Marker for Evaluating Kidney Function in Patients After Percutaneous
Ismail Karlidag1, Deniz Abat2, Adem Altunkol2
1University of Çukurova, Faculty of Medicine, Department of Urology, Adana, Turkey. dr_i_krldg@hotmail.com.
Purpose:
The purpose of this study is to evaluate the preoperative, early and late postoperative homocysteine levels and its relationship with kidney function in patients after undergoing percutaneous nephrolithotomy (PNL).
Materials And Methods:
Twenty-three patients with kidney stones underwent PNL and blood samples were taken preoperatively as well as at 48 hours and three months after the operation. The homocysteine level was determined by high pressure liquid chromatography and the fluorometric method in blood samples with ethylenediaminetetraaceticacid. The Cockcroft - Gault formula was used to calculate the glomerular filtration rate (GFR). Non-contrast computed tomography was performed for all patients before surgery. Stone burden was calculated asthe sum of the area of each stone in mm2.
Results:
Fourteen male (60.9%) and nine female (39.1%) patients were recruited for this study, and the median age was 44.3 ± 15.17 (20 - 71) years. There were no statistically significant differences between the preoperative homocysteine level and the level at 48 hours post-operation (P = .460). However, the homocysteine level three months after the operation was significantly lower than the preoperative and 48 hour levels (P = .001 and P = .003, respectively).
Conclusion:
Renal function, which deteriorated after the PNL procedure, was preserved or improved over time. Homocysteine may be a sensitive indicator to assess the change in renal function pre-and post-PNL.
Related Concept Videos
Kidney Structure
Predicting Molecular Geometry
Prediction Intervals
However, the point estimate is most likely not the exact value of the population parameter, but close to it. After calculating point estimates, we construct interval estimates, called confidence intervals or prediction intervals. This prediction interval comprises a range of values unlike the point estimate and is a better predictor of the observed sample value, y.
Levels of Organization
Molecules Are Composed of Atoms, and Biomolecules Are Assembled from Molecules:
The most basic levels include atoms, molecules, and biomolecules. Atoms, the smallest unit of ordinary matter, are composed of a nucleus and electrons. Molecules...
Leveling Effect
High-Level and Low-Level Awareness

