Are there instances when you do not perform urine microscopy and rely solely on laboratory performed urinalysis when evaluating a patient for acute kidney injury?  

Direct visualization of urinary sediment under a proper microscope is a cornerstone of AKI evaluation from intrinsic renal disease. If I am relatively sure the cause of AKI is prerenal or post-renal and AKI improves promptly with intervention, then I may forego sediment evaluation. I am in the lab l...