Secondary focal segmental glomerulosclerosis in an adolescent born with a very low birth weight

A 17-year-old man presented with a decreased renal function (creatinine clearance 66.0 ml/min/1.73 m2) and proteinuria (1.25 g/24 hrs). He was born weighing 1,065 g 26 weeks of pregnancy. He was mildly overweight (BMI 26.9 kg/m2) due to an increased weight gain (10 kg) over the past year. Renal biopsy showed perihilar sclerosing lesions in three of eleven glomeruli, low glomerular density, enlarged glomeruli, and limited fusions of foot processes, thus indicating secondary focal segmental glomerulosclerosis (FSGS). We speculated that the patient's overweight status may have caused a worsening of glomerular hyperfiltration due to the fewer number of nephrons leading to the development of secondary FSGS.