Diffuse proliferative glomerulonephritis associated with cetuximab, an epidermal growth factor receptor inhibitor

Cetuximab is an epidermal growth factor receptor inhibitor used for advanced squamous cell carcinoma of the head and neck. We report an unusual case of diffuse proliferative and crescentic glomerulonephritis in a 67-year-old man in close temporal association with cetuximab treatment for recurrent oral squamous cell carcinoma. The patient presented with acute renal failure and nephrotic-range proteinuria. Kidney biopsy showed diffuse proliferative and focally crescentic glomerulonephritis associated with immunoglobulin A (IgA)-dominant immune-complex deposition within glomerular capillary walls and mesangium. The patient showed dramatic improvement in kidney function after discontinuation of cetuximab therapy and a short course of cyclophosphamide and steroid. The clinical outcome of this case suggests that cetuximab therapy may trigger or exacerbate IgA-mediated glomerular injury and warrants close monitoring of kidney function in patients treated with this epidermal growth factor receptor inhibitor.