The Case | A 17-year-old boy with growth failure and chronic kidney disease

A 17-year-old boy with no previous medical history presented for evaluation of a left axillary mass. A review of systems was positive for eyelid, hand, and feet edema. He was normotensive. On physical examination, there was a 0.5-cm nonmobile, nontender mass in the left axilla. Laboratory evaluation was remarkable for hemoglobin of 10.8 g/dl, hematocrit of 34%, mean corpuscular volume of 99 fl, creatinine of 1.81 mg/dl, low-density lipoprotein of 244 mg/dl, and normal electrolytes. In follow-up, the left axillary mass had resolved; swelling and macrocytic anemia continued.