Nephrotic Syndrome Secondary to Renal AA Amyloidosis Predating Hodgkin Lymphoma Diagnosis: A Case Report

Introduction: AA amyloidosis is the most prevalent form of systemic amyloidosis. Common causes are chronic bacterial infections, inflammatory and autoimmune conditions. Association with solid and hematologic malignancies are uncommon. The kidneys are the most affected organ with nephrotic syndrome phenotype, though incidence is less than 1%. We present a rare case of a patient with nephrotic syndrome from AA amyloidosis with initially unknown etiology and later on proven to be from Hodgkin’s Lymphoma. Case Description: Patient is a 72M of Bosnian origin with no known medical history presenting 1 year prior with lower extremity and scrotal edema with creatinine 1.7, low albumin and proteinuria of 7g. Renal biopsy showed amorphous material and immunoperoxidase stain positive for AA amyloidosis. Infectious and autoimmune workup were unrevealing. Imaging showed retroperitoneal lymph nodes though biopsy negative for malignancy. Multiple myeloma workup negative. Patient seen by Oncology and advised treatment but was lost to follow. He presents again one year later with hemiplegia and aphasia, severe AKI on CKD (Creatinine ~10), proteinuria (~15g with 7g albumin), and a new neck mass. Workup revealed acute stroke concerning for hypercoagulable state. Patient initially resistant to invasive measures but eventually agreed on dialysis initiation. Biopsy of neck mass was pursued and was consistent with classical Hodgkin’s lymphoma. PET-CT showed metastatic disease. Treatment options discussed though decision made to defer for now. Patient maintained on chronic dialysis. Discussion: Though rare, undiagnosed malignancy should always be considered in patients with nephrotic syndrome from biopsy-proved AA amyloidosis. This case highlights the importance of thorough investigation including a complete malignancy workup in such patients.