Immune checkpoint inhibitor-related immunoglobulin A nephropathy in a patient with advanced head and neck cancer.

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of many cancers, including cancers of the head and neck. Despite the promising therapeutic efficacy of ICIs, immune-related adverse events (irAEs) are a major concern. Acute tubular injury and interstitial nephritis are the most common irAEs involving the kidneys. The present patient was diagnosed as having advanced papillary squamous cell carcinoma of the head and neck. After failure of the initial treatments, including chemotherapy, nivolumab (programmed death-1 inhibitor) was introduced. Shortly after initial administration of nivolumab, the patient developed acute kidney injury with hematuria and proteinuria. A renal biopsy and his clinical course indicated a diagnosis of ICI-related IgA nephropathy. Although glomerular involvement in irAEs is rare and challenging to treatment, the present patient was successfully treated with steroids, which improved kidney function and led to complete remission, as confirmed by urinalysis.