Post-transplant hypertension can be a diagnostic dilemma. In a select population of pediatric patients, in whom other diagnostic methods failed to reveal an abnormality, renal cortical SPECT imaging, using either Tc-99m GH or Tc-99m DMSA, revealed information that was not apparent on conventional planar renal scintigraphy. Abnormalities detected by this methodology included unsuspected renal infarct and areas of segmental perfusion deficit. The authors conclude that this methodology is a valuable tool in the evaluation of post renal transplantation hypertension in pediatric patients.