Paraneoplastic IgAN Associated with Sezary Syndrome

Introduction: Prior case reports have described acute kidney injury associated with cutaneous T cell lymphoma due to renal infiltration and paraneoplastic glomerular diseases. Sezary syndrome is the rarer leukemic variant of cutaneous T cell lymphoma. We report a case of acute kidney injury due to paraneoplastic IgA nephropathy in a patient with newly diagnosed Sezary syndrome. Case Description: A 75-year-old man with 6 months of pruritic, widespread rash and lab abnormalities was admitted for expedited workup which showed Sezary syndrome. He also had a non-oliguric acute kidney injury. Despite appropriate treatment for obstruction, volume overload, and possible tumor lysis, his creatinine uptrended. Urinalysis showed 3+ blood, 3+ protein, and casts with a total protein to creatinine ratio of 10.74 g/g. ANA, ANCA, rheumatoid factor, hepatitis B, hepatitis C, and cryoglobulin were all negative. C3 and C4 were normal at 108 and 23 mg/dL respectively. A kidney biopsy on day 20 showed acute tubular injury and membranoproliferative glomerulonephritis most consistent with IgA nephropathy. High dose steroids were started on day 49 and creatinine peaked on day 51 at 5.94 mg/dL. Renal function gradually improved and the patient never required renal replacement therapy. Discussion: This case describes paraneoplastic IgA nephropathy related to Sezary syndrome and shows improvement in renal function after starting high dose steroids. More broadly, paraneoplastic glomerular diseases are a critical diagnosis in patients with malignancy and acute kidney injury.Creatinine trend, admission = day 1A. Light microscopy: membranoproliferative glomerulonephritis with neutrophilic exudates and IgA/C3 predominance. B. Electron microscopy: mesangial and subendothelial deposits.