Lysozyme‐induced nephropathy due to systemic granulomatous disease

Lysozyme‐induced nephropathy is a rare form of acute tubular injury that has almost exclusively been reported in patients with monocytic malignancies. Typically, patients will present in acute renal failure A renal biopsy is necessary to confirm the diagnosis and will demonstrate proximal tubular cells with hypereosinophilic granules, which are periodic acid‐Schiff and Jones methenamine silver‐positive. Immunohistochemical staining for lysozyme will also be present. The following rare case will describe a case of lysozyme nephropathy in a patient without any underlying hematological malignancy, but instead with systemic granulomatous disease.