Abnormal MAG3 Renal Scintigraphy Resulting From Dehydration

Routine Tc-99m mercaptoacetyltriglycine (MAG3) renal scintigraphy in a 64-year-old quadriplegic woman revealed normal blood flow with abnormal, continual parenchymal uptake and minimal excretion into the pelvocaliceal collecting systems and urinary bladder. Because there was no clinical reason to suspect acute tubular necrosis, renal artery stenosis, or ureteropelvic junction (UPJ) obstruction, relative dehydration was considered likely. A repeat MAG3 renal scan 6 days later using intravenous fluids to ensure adequate hydration was completely normal. This case highlights the importance of patient preparation to include adequate hydration.