Acute Tubular Necrosis

Tc-99m MAG3 renal scan of a renal transplant recipient, day 1 after transplant with oliguria, shows delayed excretion of tracer from the transplant kidney. Images in vascular phase (not shown) are normal (normal perfusion and uptake).

Facts

• May occur immediately or after an initial short period of allograft function
• Related to both donor and recipient factors
• More common in cadaveric kidneys of older donors who sustained warm ischemia time or prolonged hypotensive periods
• Presented with oliguria or anuria early after transplant
• Diagnosis made by exclusion of other factors. Traditional signs (tubular casts, low urine osmolality) not reliable if patients with native partially functioning kidneys
• Treatment: supportive, return to dialysis if anuric (expected recovery of renal function usually within 3 weeks)

Renal Scan

• Normal perfusion, variable uptake but no (or delayed) excretion
• Serial scans helpful in determining viability of oliguric kidneys, predicting recovery or deterioration

Reference:

Resnick MI, Older RA. Diagnosis of Genitourinary Disease, 2nd edition, 1997