Using real-time sound touch elastography to monitor changes in transplant kidney elasticity

AIM

To use sound touch elastography (STE) to assess the changes of renal cortex among different complications following renal transplantation.

MATERIALS AND METHODS

A total of 31 patients with renal dysfunction after renal transplantation underwent an ultrasound-guided biopsy for pathological examination with conventional and STE ultrasound. The maximum elastic modulus (E_max) was determined, and the biopsy specimen was evaluated for evidence of significant differences among four different complications: drug-induced renal damage, acute rejection, chronic allograft nephropathy (CAN), and BK virus (BKV) nephropathy. Receiver operator characteristics were used to compare the diagnostic efficacy of STE ultrasound according to the pathological results.

RESULTS

The quantitative index E_max of the STE technique was statistically significant among the four different complications (p<0.05). The distribution of the magnitude of E_max in the renal cortex was BKV nephropathy > CAN > acute rejection > drug induced renal damage. The renal cortex E_max was statistically different for the severity of renal fibrosis and tubular atrophy (p<0.05).

CONCLUSION

Each of the four different complications of transplantation influenced the E_max of the renal cortex differently. E_max can be used to assess the severity of renal fibrosis and tubular atrophy.