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Non-invasive Evaluation of Graft Condition in Adult Patients With Kidney Transplant Using Ultrasound Localization Microscopy and Multispectral Optoacoustic Tomography

Non-invasive Evaluation of Graft Condition in Adult Patients With Kidney Transplant Using Ultrasound Localization Microscopy and Multispectral Optoacoustic Tomography

Status
Recruiting
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT06472947
Acronym
ESTIMATOR
Enrollment
10
Registered
2024-06-25
Start date
2024-06-18
Completion date
2028-01-18
Last updated
2026-03-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Kidney Biopsy, Kidney Transplant

Brief summary

In this study, the condition of the kidney transplant in adults is to be assessed non-invasively using Multispectral Optoacoustic Tomography and Ultrasound Localization Microscopy (ULM). ULM imaging can be performed in a 2-dimensional and a 3-dimensional way (2D and 3D ULM). Therefore, "ULM" in the following texts and measures will refer to 2D and 3D ULM. New, non-invasive markers that allow conclusions to be drawn about the condition of the transplant should reduce the need for invasive diagnostic procedures in the future.

Detailed description

In this study, the condition of the kidney transplant in adults is to be assessed non-invasively using multispectral multispectral optoacoustic tomography and ultrasound localization microscopy. Associated with common diseases such as arterial hypertension, diabetes mellitus and cardiovascular diseases, chronic renal failure is now a leading cause of death worldwide. Around 10% of adults in Germany, but children are also affected. The terminal stage of renal insufficiency is defined by a glomerular filtration rate (GFR) which is only 15% of the normal rate and the need for renal replacement therapy in the form of dialysis or transplantation. Not only the higher quality of life, but also the mortality rate make kidney transplantation the procedure of choice whenever possible. After successful kidney transplantation, regular monitoring and evaluation of the organ transplant is of great importance to detect a rejection reaction as early as possible. Among other things, this is done during an extensive annual examination. Not infrequently, and especially in the case of abnormalities in the laboratory diagnosis of blood and urine, a kidney biopsy is also necessary in order to assess the condition of the transplant in the best possible way. As an invasive diagnostic procedure, the biopsy necessitates a stay in hospital, may result in side effects such as postoperative bleeding and represents a risk and an additional bruden for the patient. MSOT has already been used to measure renal clearance and the biodistribution of fluorescent substances within the kidney, but new biomarkers have also been established in muscle and intestinal diseases and correlated with clinical scores. ULM has made the visualization of glomeruli, the smallest functional unit of the kidney, in living rats and humans and visualization of cerebral microvasculature in the human brain possible. In this study, the renal function in transplant patients will be evaluated as part of the annual examination and results from histology (biopsy), laboratory and ultrasound diagnostics will be correlated with data from MSOT and 2D and 3D ULM imaging. The investigators believe that MSOT can be used to gain important molecular insights into the condition of the transplant. With ULM the investigators want to analyze the microvascular architecture within glomerular renal corpuscles and identify changes in perfusion dynamics as morphological signs for transplant evaluation.

Interventions

DEVICEULM and MSOT

transplanted kidney will be examined non-invasively with ULM and MSOT

Sponsors

University of Erlangen-Nürnberg Medical School
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* kidney transplant * indication for biopsy set in clinical routine * minimum 18 years of age * written consent

Exclusion criteria

* allergy against contrast agents/ SonoVue * tatoos in examined areas * contraindication against SonoVue * pregnant women * breast feeding women

Design outcomes

Primary

MeasureTime frameDescription
MSOT in human kidney transplantDay1Measuring MSOT signals (Signals for total/oxygenated/deoxygenated hemoglobin, lipid and collagen) in the human kidney transplant
Visualization of microvascular architecture in the transplant kidneyDay1Using Ultrasound Localization Microscopy (ULM) for the non invasive visualization of microvasculature
Quantification of microvascular dynamics in the transplanted kidneyDay1Using Ultrasound Localization Microscopy (ULM) for the non invasive quantification of microvascular dynamics

Secondary

MeasureTime frameDescription
ULM visuals and histologyDay1ULM: Correlation of the vascular architecture of the transplant kidney visualized by ULM (e.g. number of segmented glomeruli) with histological parameters (e.g. Banff classification)
ULM visuals and laboratory resultsDay1\- ULM: Correlation of the vascular architecture of the transplant kidney visualized by ULM (e.g. number of segmented glomeruli) with laboratory chemical parameters (e.g. renal function parameters, inflammation parameters, immunological parameters)
ULM visuals and standard sonographyDay1\- ULM: Correlation of the vascular architecture of the transplant kidney visualized by ULM (e.g. number of segmented glomeruli) with sonographic parameters (e.g. resistance index (RI), flow velocity)
ULM quantification and histologyDay1ULM: Correlation of parameters of quantified microvascular perfusion dynamics in the transplant kidney with histological parameters (e.g. Banff classification)
ULM quantification and laboratory resultsDay1\- ULM: Correlation of parameters of the quantified microvascular perfusion dynamics in the transplant kidney with laboratory chemical parameters (including renal function parameters, inflammation parameters)
MSOT: Hb and histologyDay1MSOT: Correlation of the signal determined with MSOT for total/oxygenated/deoxygenated
MSOT: hb and laboratory resultsDay1\- MSOT: Correlation of the signal for total/oxygenated/deoxygenated hemoglobin with laboratory chemical parameters
MSOT hb and sonographyDay1\- MSOT: Correlation of the signal for total/oxygenated/deoxygenated hemoglobin determined with MSOT with sonographic parameters
MSOT hb and histologyDay1\- MSOT: Correlation of the signal for total/oxygenated/deoxygenated hemoglobin with with histological parameters
MSOT Lipid and laboratory resultsDay1\- MSOT: Correlation of the signal for lipid determined with MSOT with laboratory chemical parameters
MSOT Lipid and sonographic resultsDay1MSOT: Correlation of the signal for lipid determined with MSOT with sonographic parameters parameters
MSOT lipid and histologyDay1MSOT: Correlation of the signal for lipid determined with MSOT with histological parameters
MSOT collagen and sonographyDay1\- MSOT: Correlation of the signal for collagen determined with MSOT with sonographic parameters
MSOT collagen and histologyDay1MSOT: Correlation of the signal for collagen determined with MSOT with histological parameters
MSOT collagen and laboratory resultsDay1\- MSOT: Correlation of the signal for collagen determined with MSOT with laboratory chemical parameters
ULM quantification and sonographyDay1Correlation of parameters of the quantified microvascular perfusion dynamics in the transplant kidney with sonography in transplanted kidney

Countries

Germany

Contacts

CONTACTFerdinand Hannah Knieling, PD Dr. Dr.
ferdinand.knieling@uk-erlangen.de0049 9131 85 33118
CONTACTAdrian Regensburger, PD Dr. Dr.
adrian.regensburger@uk-erlangen.de0049 9131 33118
PRINCIPAL_INVESTIGATORFerdinand Knieling, PD Dr. Dr.

FAU Erlangen-Nuremberg

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 5, 2026