A preliminary report on (99m)Tc-fanolesomab imaging of renal allograft.

OBJECTIVE

To evaluate the utility of (99m)Tc-fanolesomab (a (99m)Tc-labeled murine monoclonal immunoglobulin M antibody that specifically binds cluster designation 15 antigens on human neutrophillic leukocytes with high sensitivity and specificity) in diagnosing localized infections.

METHODS

Five patients with renal allografts were imaged using (99m)Tc-fanolesomab to look for a source of infection. Images were obtained between 2 and 4 h after injection of fanolesomab labeled with 15-20 mCi (99m)Tc. Imaging results were correlated with patients' culture results and clinical outcome.

RESULTS

Two patients showed a significant increase in renal allograft uptake and were found to have allograft pyelonephritis. One patient who developed a severe acute renal failure secondary to humoral rejection (antidonor human leukocyte antigen antibody-mediated rejection with polymorphonuclear capillaritis and glomerulitis) showed uptake similar to the lower lumbar spine. One patient with normal allograft function showed a significantly increased uptake, especially in the pelvis of the allograft, indicating normal excretion of the free (99m)Tc-pertechnetate by the allograft. The fifth patient who had been off immunosuppressive therapy and on maintenance hemodialysis for 4 months showed tracer uptake similar to the lumbar spine, suggestive of chronic allograft rejection.

CONCLUSION

This preliminary study describes different patterns of (99m)Tc-fanolesomab scan in renal allografts during episodes of kidney infection, rejection, or normal function. It suggests that (99m)Tc-fanolesomab can be used to evaluate renal allograft complications.