BACKGROUND: Blood oxygen level-dependent MRI (BOLD MRI) can be used to assess intra-renal oxygen bioavailability by measuring the R2(*) level, which reflects tissue deoxyhaemoglobin levels. This study was designed to identify the significance of BOLD MRI in differentiation of acute rejection (AR) and acute tubular necrosis (ATN) in patients within 6 months after kidney transplantation. METHODS: Eighty-two patients with normal graft function and 28 patients with biopsy-proven AR (n = 21) or ATN (n = 7) were enrolled. Patients with normal functioning allograft underwent BOLD MRI within 2 to 3 weeks post-transplantation, while patients with AR and ATN underwent BOLD MRI within 6 days before or after kidney transplant biopsy. Cortical R2(*) (CR2(*)) and medullary R2(*) (MR2(*)) levels were measured. RESULTS: The mean CR2(*) level was significantly higher in the ATN group (15.25 +/- 1.03/s) compared to the normal group (13.35 +/- 2.31/s, P = 0.028) and AR group (12.02 +/- 1.72/s, P = 0.001). There was a significant difference also between the AR group and normal group on CR2(*) levels (P = 0.013). The mean MR2(*) level was significantly lower in the AR group (14.02 +/- 2.68/s) compared to the normal group (16.66 +/- 2.82/s, P < 0.001) and ATN group (19.47 +/- 1.62/s, P < 0.001). There was also a significant difference between the ATN group and normal group on MR2(*) levels (P = 0.011). There were no correlations between characteristics such as patient age, post-operation time, post-biopsy time, Scr level, HB level, urine output volume, MAP level, CNI trough concentration and R2(*) levels, except between MAP level and CR2(*) level (P = 0.029). CONCLUSIONS: BOLD MRI could be a valuable method to discriminate between AR and ATN by measuring tissue oxygen bioavailability in early kidney allograft dysfunction.
BACKGROUND: Blood oxygen level-dependent MRI (BOLD MRI) can be used to assess intra-renal oxygen bioavailability by measuring the R2(*) level, which reflects tissue deoxyhaemoglobin levels. This study was designed to identify the significance of BOLD MRI in differentiation of acute rejection (AR) and acute tubular necrosis (ATN) in patients within 6 months after kidney transplantation. METHODS: Eighty-two patients with normal graft function and 28 patients with biopsy-proven AR (n = 21) or ATN (n = 7) were enrolled. Patients with normal functioning allograft underwent BOLD MRI within 2 to 3 weeks post-transplantation, while patients with AR and ATN underwent BOLD MRI within 6 days before or after kidney transplant biopsy. Cortical R2(*) (CR2(*)) and medullary R2(*) (MR2(*)) levels were measured. RESULTS: The mean CR2(*) level was significantly higher in the ATN group (15.25 +/- 1.03/s) compared to the normal group (13.35 +/- 2.31/s, P = 0.028) and AR group (12.02 +/- 1.72/s, P = 0.001). There was a significant difference also between the AR group and normal group on CR2(*) levels (P = 0.013). The mean MR2(*) level was significantly lower in the AR group (14.02 +/- 2.68/s) compared to the normal group (16.66 +/- 2.82/s, P < 0.001) and ATN group (19.47 +/- 1.62/s, P < 0.001). There was also a significant difference between the ATN group and normal group on MR2(*) levels (P = 0.011). There were no correlations between characteristics such as patient age, post-operation time, post-biopsy time, Scr level, HB level, urine output volume, MAP level, CNI trough concentration and R2(*) levels, except between MAP level and CR2(*) level (P = 0.029). CONCLUSIONS: BOLD MRI could be a valuable method to discriminate between AR and ATN by measuring tissue oxygen bioavailability in early kidney allograft dysfunction.
Authors: Benjamin D Humphreys; Vincenzo Cantaluppi; Didier Portilla; Kai Singbartl; Li Yang; Mitchell H Rosner; John A Kellum; Claudio Ronco Journal: J Am Soc Nephrol Date: 2015-11-18 Impact factor: 10.121
Authors: Jeff L Zhang; Glen Morrell; Henry Rusinek; Lizette Warner; Pierre-Hugues Vivier; Alfred K Cheung; Lilach O Lerman; Vivian S Lee Journal: Am J Physiol Renal Physiol Date: 2014-01-22
Authors: Elizabeth A Sadowski; Arjang Djamali; Andrew L Wentland; Rebecca Muehrer; Bryan N Becker; Thomas M Grist; Sean B Fain Journal: Magn Reson Imaging Date: 2009-07-03 Impact factor: 2.546