When do you perform a kidney biopsy in a patient with AKI that is thought to be related to an immune checkpoint inhibitor?

I would wait for the response to corticosteroid therapy before the renal biopsy.

The kidney biopsy offers both diagnostic and prognostic information so I personally pursue the renal biopsy unless there is a compelling reason not to (i.e. coagulopathy). Although ATIN is the most common lesion found on renal bx performed for the evaluation of CPI-AKI, other actionable renal diseases have been reported in several case series. The ASCO guidelines suggest that the renal bx should only be performed if the patient does not respond to steroids. Nephrologists were not involved in the...