In patients with intrinsic acute kidney injury of unknown etiology and with pending kidney biopsy results, are there instances when you would recommend a trial of glucocorticoids?  

I usually don't if I know I will have preliminary results of the biopsy within 24-36 hours. I do sometimes when it is not possible to do the biopsy in a timely manner. I don't think a 1-2 day delay would make a major difference in the amount of kidney damage.