Bilateral Primary Renal Lymphoma Presented As Homogenous Renal Enlargement And Acute Interstitial Nephritis

Primary renal lymphoma(PRL) is an extremely rare form of extranodal lymphoma andexhibitsas single (10-20%), multifocal nodules (60%), renal invasion from contiguous retroperitoneal disease (25-30%), diffuse infiltration (20%) or perirenal involvement (10%)[1] .Here we report a case of bilateral primary renal lymphoma in a 13 year-old boy who presented with homogenous nephromegaly and acute interstitial nephritis(AIN).The renal biopsy revealed primary renal T lymphoblastic lymphoma. Hyper-CVAD regimen was initiated and the renal function had been recovered after the first round of chemotherapy. To our knowledge, there have only been three reports of primary renal T lymphoblastic lymphoma including ours so far. All the three patients were young and showed as AIN and bilateral renal enlargement. We also reviewed 16 cases of PRL presenting with AIN and enlarged kidneys that have been reported since 1997. Although PRL is quite rare, it must be taken into account when making a differential diagnosis of AIN. Renal biopsy is the gold standard and intensive chemotherapy can preserve the renal function.