Introduction: The thymus gland is a lymphoid organ located in the anterior mediastinum, especially associated with T cell proliferation. Rebound thymic hyperplasia may develop in the thymus after stressful situations for the body, such as immunosuppression, chemotherapy, major surgery or burns.
Purpose of the study: To determine the incidence of rebound thymic hyperplasia in the clinical follow-up of these patients by retrospectively scanning the thorax CT scans of renal transplantation patients performed in our hospital. Additionally, our study aimed to evaluate the relationship between thymic hyperplasia and allograft rejection.
Material-Methods: 324 patients who underwent renal transplantation surgery in our hospital between January 2012 and October 2023 were evaluated. All control CT scans between the ninth and fifty-fourth months after the operation were retrospectively scanned. A total of 630 CT images were evaluated.
Results: 112 of the 324 patients evaluated were excluded from the study for various reasons.Thymic hyperplasia was detected in 10 (4.71%) of the remaining 212 patients. Pathology-proven rejection was detected in 4 of these 10 patients (40%).In these patients, acute T cell-mediated rejection was detected in 3 of them and acute humoral rejection was detected in 1 of them, on the basis of chronic rejection.
Conclusion: We think that the possible immune stimulation that may develop due to hyperplasia in the thymus in patients receiving immunosuppression therapy after transplantation surgery may cause an increase in the risk of rejection.