Radionuclide Imaging in the Evaluation of the Functional State of the Transplanted Kidney in the Post-Transplant Period
Objective: The aim of our clinical study was to evaluate the possibility of diagnosis of postrenal-transplantation complications in recipients using dynamic scintigraphy basing on temporary parameters standard zones of interest and medullary zone of renal transplantat comparing the results with the histological findings. Methods: We determined time of maximum and one-half maximal activity of radiopharmaceutical medication in renal transplantat, parenchyma and medullary zone the graft. According to pathological diagnosis, patients were categorized into three groups: first - normals (n =32), second - acute rejection (n =43), third - chronic nephropathy (n =43). Results: In this study 118 patients aged 21-60 (38.4±9,8) years were included who underwent dynamic renal scintigraphy and biopsy renal transplantat. The time of maximum activity radiopharmaceuticals parenchyma the graft in patients in first group - 3.24±0.54 min, second - 6.61±3.28 min, third - 6.21±4.17 min (р <0,001). The time of maximum activity radiopharmaceuticals medullary zone the graft in patients in first group - 3.95±0.95 min, second - 8.94±5.23 min (р <0,001), third - 7.29±4.16 min (р <0,01). The time of maximum activity radiopharmaceutical the whole graft in patients in first group - 3.87±0.62 min, second - 7.4±3.82 min (р <0,001), third - 8.03±4.28 min (р <0,01). The time one-half maximal activity radiopharmaceuticals parenchyma the graft in first group - 10.4±2.95 min, second - 37.09±3.89 min (р <0,001), third - 29.67±3.1 min (р <0,005). The time one-half maximal activity radiopharmaceuticals medullary zone the graft in first group - 11.71±5.93 min, second - 79.34±9.81 min (р <0,001), third - 29.67±3.95 min (р <0,005). The time one-half maximal activity radiopharmaceuticals the whole graft in first group - 12.31±3.91 min, second - 53.29±8.22 min, third - 52.71±7.86 min (р <0,001). Anderson-Bahadur distance: Т <sub>1/2</sub> medullary zone the graft most significant between first and second groups patients (17.43), gives maximum index value at chronic nephropathy (-9.07), at differentiation between acute rejection and chronic nephropathy (8.48). Estimate of the area under the ROC indicate most informative time of maximum accumulation of the radiopharmaceutical of the whole graft (S <sub>ROC</sub> =0.907) in acute rejection and Tmax parenchyma the renal transplantat (S <sub>ROC</sub> =0.847) in patients with chronic nephropathy the graft. Sensitivity and specificity renal scintigraphy parameters of diagnosing on postrenal transplantation complications amounted 71.43-98.7% and 67.7-96.43% respectively. Conclusion: Renal scintigraphy is an additional test for early detection on postrenal transplantation complications and correct tactics conducting recipients. The parameters of kinetics of nephrotropic radiopharmaceuticals provide diagnosis of acute rejection and chronic nephropathy the graft. Inclusion of radionuclide diagnostics to monitor the state renal transplantat optimizes approach to biopsies graft.