Prediction of renal transplant survival from early postoperative radioisotope studies.
It has been routine at the University of Alabama Medical Center to obtain a radionuclide renal function study immediately after transplantation (usually within 3 d) that includes estimation of effective renal plasma flow (ERPF) from a single plasma sample in addition to imaging. We present here the correlation between baseline measurements and the 1-y graft survival.


METHODS
Two cohort years were reviewed: 1988, when 131I-orthoiodohippurate (OIH) was used; and 1995, when 99mTc-mercaptoacetyltriglycine (MAG3) was used. ERPF was measured concurrently with gamma-camera imaging by previously published single-injection, single-sample methods (converting MAG3 clearance to ERPF by means of a correction factor).


RESULTS
Graft survival during the first postoperative year improved significantly in the interval between cohort years, from 74% of 147 cadaver (CD) grafts in 1988 to 91% of 200 CD grafts in 1995 (log rank test, P < 0.05). In contrast, for living related donor (LRD) grafts there was no significant change, from 91% of 66 in 1988 to 91% of 83 in 1995. The baseline ERPF was a significant predictor of graft survival in both 1988 and 1995 (Wilcoxon test, P > 0.05). For LRD grafts the association was not significant in either year. Using MAG3 (1995), the peak time and the ratio of counting rate (R) at 20 min to that at 3 min (R20:3) were also significant predictors for CD graft survival. Using OIH (1988 cohort), the correlation with peak time did not reach significance, and the R20:3 measurement was not available. Although multivariate combinations (Cox proportional hazards model) did not have significantly more predictive value at the 95% confidence level than ERPF or R20:3 alone, some statisticians suggest a 75% confidence level for adding an additional covariate to a multivariate model. Use of this level led to a model including both ERPF and R20:3.


CONCLUSIONS
Single-sample ERPF measured in the immediate post-transplant period, whether from OIH clearance or MAG3 clearance, was a statistical predictor of graft survival for CD transplants. For MAG3, the peak time and R20:3 were also significant predictors. These associations held only for CD transplants and not for LRD transplants.
Russell
C D
CD
University of Alabama Hospital and VA Medical Center, Birmingham 35233, USA.
Yang
H
H
Gaston
R S
RS
Hudson
S L
SL
Diethelm
A G
AG
Dubovsky
E V
EV
D015331:Cohort Studies; D006085:Graft Survival; D006801:Humans; D007457:Iodine Radioisotopes; D007465:Iodohippuric Acid / Q000493:pharmacokinetics; D007677:Kidney Function Tests / Q000379:methods; D016030:Kidney Transplantation / Q000401:mortality / Q000502:physiology*; D008657:Metabolic Clearance Rate; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012039:Regional Blood Flow; D012079:Renal Circulation; D012189:Retrospective Studies; D015996:Survival Rate; D017263:Technetium Tc 99m Mertiatide / Q000493:pharmacokinetics
D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals; D007465:Iodohippuric Acid; D017263:Technetium Tc 99m Mertiatide