Post-transplant lymphoproliferative disorder of kidney: a case report and literature review

Objective To improve clinicians' understanding of post-transplant lymphoproliferative disorder (PTLD) after renal transplantation, a rare case of this disease was reported and literature was reviewed. Method The clinical data and pathological changes of the allograft, immunohistochenmistry (IHC) and in situ hybridization (ISH) were analyzed. In addition, the relevant literature was reviewed. The clinicopathological features and differential diagnoses of PTLD were discussed. Result A renal mass (5.6 cm×5.4 cm), which was suggestive of primary renal malignancy, had been detected on the patient after received renal transplantation for a year and a half. Grossly, the mass was 7cm in diameter, with fleshy texture. Microscopically, the renal parenchyma was destructed and infiltrated with massive inflammatory cells, mostly lymphoid cells and occasionally Reed-Sternberg-like cells. IHC showed CD20 and CD79a were predominantly expressed in lymphoid cells. ISH showed diffused Epstein-Barr virus encoded RNAs (EBERs) positivity. The above findings were consistent with PTLD, polymorphic B cell hyperplasia (polymorphic PTLD), with concurrent Epstein-Barr virus infection. Conclusion Lymphoid infiltration in a renal allograft needs to be differentiated from T-cell rejection, viral infection, nephropyelitis, as well as PTLD. Early detection and proper management of PTLD may help improve the graft survival rate.