Abstract
A previously healthy 53-year-old male with primary membranous nephropathy (positive anti phospholipase A2 antibody) presented to our hospital with worsening cough, shortness of breath, hypotension, and malaise. During his hospital stay, he quickly progressed to overt respiratory failure requiring mechanical ventilation. Upon further workup, he met clinical criteria for tumor lysis syndrome due to an unknown diffuse large B-cell lymphoma, who underwent rapid cytolysis after starting stress dose steroids.