A 40-year-old Brazilian male presented to the emergency department after experiencing syncope. Over the past 4 months, he had complained of fatigue and was diagnosed with folate- and iron-deficiency anemia, for which he received treatment. Subsequently, he developed malaise and anorexia, and experienced an 8 kg weight loss over 2 months. Four weeks before admission, he noticed purpura and petechiae on his lower limbs. He reported normal urine output, with no gross hematuria, and denied substance abuse, new medications, allergies, or a family history of kidney disease.