Evaluation of kidney grafts with 99mTc-methylene diphosphonate within 36 hours after transplantation: a marker of ischemic damage.

In order to evaluate renal ischemic damage in transplanted kidneys, renal scintigraphy with 99mTc-methylene diphosphonate was performed in 30 kidney grafts within 36 h after transplantation. The renal uptake was monitored for 100s at 10-min intervals during 90 min following injection. Seventeen patients had an average uptake of radioactivity in the kidney on the 60-, 70-, 80-, and 90-min scintigrams expressed as a percentage of the activity present on the 10-min scintigram of 150% or less (low) and 13 patients had an average uptake of radioactivity of above 150% (high). There was no relationship between the average uptake of radioactivity and warm and cold ischemia times (or the combined value: corrected ischemia), maximal function, reversible rejection, and ureteral obstruction. A significant correlation was found between the average uptake of radioactivity in the kidney and onset of function. Seventy-six per cent of the grafts with a low average uptake of radioactivity had an onset of function on or before day 10 after operation (early) whereas only 15% of the kidneys with a high average uptake of radioactivity had an early onset of function. Twelve per cent of the patients with a low average uptake of radioactivity in the kidneys had their grafts removed for various reasons within 2 months after transplantation, whereas 54% with a high average uptake of radioactivity had their grafts removed. It is concluded that 99mTc-methylene diphosphonate scintigraphy may be useful in the prognostic assessment of graft onset of function and of graft survival.