Renal Allograft Accumulation of Technetium-99m Sulfur Colloid as a Predictor of Graft Rejection

Non-invasive approaches in the diagnosis of acute rejection in kidney transplant recipients. Part I.In vivoimaging methods

“…However, 125 I is not suited for scintigraphic imaging, and this tracer has never been used in routine clinical practice [60]. Finally, 99m Tc-sulfur colloid is trapped in fibrin thrombosis associated with AR [9, 60]. The accumulation of 99m Tc-sulfur colloid in kidney grafts is independent of renal function.…”

“…The accumulation of 99m Tc-sulfur colloid in kidney grafts is independent of renal function. Imaging after infusion of 99m Tc-sulfur colloid appeared to discriminate AR on the basis of a strictly visual scale [9]. Unfortunately, several studies using computer-assisted quantification of allograft uptake compared with the surrounding pelvis showed conflicting results, with false-negative and false-positive rates that were too high to make 99m Tc-sulfur colloid useful in predicting renal AR in routine clinical practice [65].…”

“…Moreover, repeated biopsies to evaluate the renal graft's status pose challenges, including practicability and cost. Therefore, alternative, less invasive but highly sensitive modalities are currently under investigation to reinforce our armamentarium in the diagnosis of AR [1, 9–15]. Likewise, it would be useful to non-invasively predict non-rejection in KTRs with acute renal dysfunction and suspected AR in order to avoid needless transplant biopsy.…”

Fluorodeoxyglucose F18 Positron Emission Tomography Coupled With Computed Tomography in Suspected Acute Renal Allograft Rejection

“…Moreover, repeated biopsies to evaluate a renal graft's status pose challenges, including practicability and cost. Consequently, other sensitive and less invasive modalities, including gene expression profiling and omic analyses of blood and urine samples as well as in vivo imaging, are currently under investigation to reinforce our clinical armamentarium for AR diagnosis (2,(7)(8)(9). Likewise, it would be useful to noninvasively predict nonrejection in kidney transplant recipients (KTRs) with acute renal dysfunction and suspected AR, thereby avoiding unnecessary transplant biopsy.…”

“…Comparative meta-analysis suggested a similar specificity of graft labeling during rejection using either radiotracer (19). Still, in clinical settings within the permissible radiation dose, technetium Tc 99m ( 99m Tc) SC appeared to better discriminate AR on the basis of a strictly visual scale (9). Unfortunately, several studies using computer-assisted quantification of Tc SC uptake by the allograft in comparison to the surrounding pelvis showed conflicting results, with false-negative and -positive rates that were too high to make 99m Tc SC useful in predicting renal AR (20).…”