How do you risk-stratify contrast exposure after apparent renal recovery in a patient within 30 days of dialysis-requiring AKI?

The risk of repeat ATN is actually lower during the recovery phase of AKI, but not zero. If the patient's renal function is worsening after improving, then I would consider other diagnoses besides ATN (obstruction, etc.). However, if the scenario fits, then ATN may be the diagnosis.