Nephrology
COHORT
● Cohort
Standardized sonographic parameters POV and PVD show association with chronic injury in kidney transplant dysfunction
Frontiers in Medicine
Published April 1, 2026
DOI ↗
A retrospective single-center cohort study analyzed 350 kidney transplant biopsies performed between 2013 and 2022. The study evaluated the association between standardized color-coded duplex sonography (CCDS) parameters—percentage of vascularization (POV), periphery vessel distance (PVD), and resistive index (RI)—and histopathologic findings based on Banff criteria in kidney transplant recipients undergoing biopsy for allograft dysfunction.
The main results showed that POV > 50% had independent negative predictors including recipient age, severe tubular atrophy (ct), and arterial intimal fibrosis (cv). PVD ≥ 0.25 cm was associated with recipient age and moderate tubular atrophy (ct). No association was found between RI and histopathologic lesions. Specific effect sizes, absolute numbers, and p-values or confidence intervals were not reported for these associations.
Safety and tolerability data were not reported. The primary limitation is the retrospective single-center design. The study's practice relevance is that CCDS parameters POV and PVD may serve as non-invasive markers of chronic allograft injury and could support—but not replace—biopsy evaluation in clinical assessment. Biopsy remains essential for establishing a definitive diagnosis in graft dysfunction.
For someone with a transplanted kidney, signs of trouble are deeply worrying. Figuring out what's wrong usually means a biopsy—a procedure to take a tiny piece of tissue for analysis. It's essential, but it's also invasive. Doctors are always looking for less invasive ways to get information.
Researchers looked back at 350 kidney transplant biopsies to see if certain ultrasound measurements taken just before the biopsy could hint at the damage found inside. They found that two measurements—how much of the kidney tissue showed blood flow (called POV) and how far small blood vessels were from the kidney's edge (called PVD)—were linked to signs of chronic scarring and damage seen under the microscope. A third common measurement, the resistive index (RI), didn't show any such link.
This is a single-center, retrospective look at past data, which means it's an early observation, not proof. The study wasn't designed to test if ultrasound can diagnose problems on its own. The authors are clear: while these ultrasound signs might one day support monitoring, a biopsy remains the essential, definitive tool for diagnosing what's harming the transplant.
What this means for you: Ultrasound may offer clues to kidney transplant damage, but biopsy is still the gold standard.
View Original Abstract ↓
Sonography is a key method in examining kidney transplants. Recent reports on the limited diagnostic value of an elevated resistive index (RI) in detecting rejection have cast doubt on the overall utility of color-coded duplex sonography (CCDS). This study evaluated additional CCDS parameters – percentage of vascularization (POV) and periphery vessel distance (PVD) – and investigated their association with histopathologic findings in allograft dysfunction. In a retrospective single-center study, 350 kidney transplant biopsies performed between 2013 and 2022 were analyzed. Standardized sonographic evaluation, including POV, PVD, and RI, was conducted at biopsy request. Histopathologic lesions were scored according to Banff criteria. Multivariable logistic regression identified independent predictors of abnormal CCDS parameters. Recipient age, severe tubular atrophy (ct), and arterial intimal fibrosis (cv) were independent negative predictors of POV > 50%. PVD ≥ 0.25 cm was associated with recipient age and moderate tubular atrophy (ct). RI showed no association with histopathologic lesions. These findings identify POV and PVD as non-invasive markers of chronic injury in kidney allografts, highlighting their potential adjunctive role in detecting parenchymal damage. As such, CCDS may support – but not replace – biopsy, which remains essential for establishing a definitive diagnosis in graft dysfunction.
