Pembrolizumab-induced focal segmental glomerulosclerosis: A case report

Area of Science:

• Nephrology
• Oncology
• Immunology

Background:

• Focal segmental glomerulosclerosis (FSGS) is a leading cause of end-stage kidney disease.
• Immune checkpoint inhibitors like pembrolizumab (anti-PD-1) can induce renal immune-related adverse events.
• FSGS is an infrequently reported renal complication of anti-PD-1 therapy.

Observation:

• A 46-year-old woman presented with generalized edema and nephrotic syndrome.
• Kidney biopsy confirmed FSGS after excluding other causes.
• The patient was diagnosed with FSGS secondary to pembrolizumab treatment.

Findings:

• The patient received supportive care with irbesartan and furosemide, discontinuing pembrolizumab.
• Nephrotic syndrome features resolved within two months of treatment cessation and supportive care.

Implications:

• This case highlights FSGS as a potential renal immune-related adverse event of PD-1 inhibitor therapy.
• Routine renal function and urinalysis monitoring are recommended for patients on PD-1 inhibitors.
• Kidney biopsy is advised for patients with unexplained proteinuria or renal injury during PD-1 inhibitor treatment to guide management.