Utility of Doppler Ultrasound as the Primary Imaging Modality in Renal Graft Dysfunction,MOHAMED S. EL-SHARKAWY, MOHAMED A. BEDEWI and TAJUDDIN O. MALIBAREY
Abstract
Background: Doppler ultrasonography is a noninvasive imaging modality with no ionizing radiation or contrast administration that can be applied for renal transplant regardless of renal functions. It is routinely used by many clinicians to diagnose graft dysfunction postoperatively and during long-term follow-up to identify its possible etiology and also to guide graft biopsy.
Aim of the Work: To explore the utility of Doppler ultra-sound as the primary modality in the assessment of renal graft dysfunction with main correlation with renal biopsy.
Material and Methods: The subject of this study was 79 consecutive live-related renal graft patients presented with graft dysfunction. Initial assessment was done by ultrasound (US) in all patients using power, Color and Pulsed Doppler with serial US in suspected acute rejection and acute tubular necrosis. Renal biopsy was done in 55 patients, MAG3 scin-tigraphy done in 42 patients. MM and CT done in case of graft-related masses (n=2). MR Angiography (MRA) and catheter angiography (n=2) were done when renal artery stenosis (TRAS) was diagnosed on US.
Results: Patient's age range was 25-62 years. Out of 55 patients with graft dysfunction underwent biopsy, 3 patients revealed recurrence of original disease, 5 acute tubular necrosis (ATN), 21 acute rejection, chronic rejection (n=14) and collections (n=10). Renal graft mass (undifferentiated carci-noma) was discovered (n=1), compressing adnexal mass (n=1) revealed by US (n=2), unenhanced CT (n=1) unenhanced MRI (n=1). As regard parenchymal complications, Doppler/ Biopsy agreement was 87.57% in chronic graft rejection, recurrence of original disease (66.7%), acute rejection (57.14%) and the least was ATN (40%). Peritransplant collection (one abscess, 2 lymphoceles, 8 seroma, 1 urinoma and hematoma), were depicted on US and proven by aspiration ultrasound-guided biopsy (n=10) and MM (n=2) with 100% agreement. Vascular complications (n=3) were vascular thrombosis (n=1) and TRAS (n=2). TRAS was diagnosed by Doppler in 2 patients and proven by Angiography (n=2) and MRA (n=2) and confirmed by relief of signs on follow-up Doppler US after PTA (percutaneous transluminal angioplasty).
Conclusion: Doppler ultrasound is a safe sensitive non-invasive procedure in assement of Renal Graft dysfunction particularly when using serial PI and RI measurements in addition to Power Doppler parameters described. Doppler US is still having low specificity in differentiating parenchymal entities of graft dysfunction with better value in follow-up and in patient's selection for biopsy. It has high sensitivity in diagnosing vascular complications and peri-graft collections.