Contrast Volume as a Predictor of Kidney Injury Following Contrast-Enhanced CT

September 6, 2026 updated by: Mansour Saleh Hamed Amar, Assiut University

Prospective Evaluation of Contrast Volume as a Predictor of Contrast-Associated Acute Kidney Injury Following Intravenous Contrast-Enhanced Computed Tomography

Iodinated contrast dye used during computed tomography (CT) scans can sometimes cause kidney stress or damage, known as contrast-associated acute kidney injury (CA-AKI). Currently, doctors evaluate a patient's kidney safety using standard estimated glomerular filtration rate (eGFR). However, standard eGFR is calculated for an average body size rather than an individual's actual body size, which can misrepresent a person's true kidney excretion capacity. This study aims to evaluate whether comparing the volume of contrast dye directly to a patient's true, individualized kidney function (the contrast volume-to-absolute GFR ratio) can accurately predict the risk of developing kidney injury after an intravenous contrast-enhanced CT scan.

This is a prospective, observational study involving adult outpatients who are already scheduled for a clinically necessary contrast-enhanced CT scan. Participation is observational and does not alter the patient's planned scan, medical treatment, or the amount of contrast dye administered by their healthcare team.

Participants will:

  • Have their baseline kidney function assessed through a routine blood test (serum creatinine) within 48 hours prior to their CT scan.
  • Have their height and weight recorded to calculate their individualized, absolute kidney function.
  • Complete a follow-up blood test (serum creatinine) 48 to 72 hours after the CT scan to evaluate any changes in kidney function.

Researchers will analyze whether the ratio of contrast volume to absolute kidney function reliably identifies patients at higher risk of contrast-associated kidney complications, helping to establish safer, personalized contrast dosing strategies in the future.

Study Overview

Study Type

Observational

Enrollment (Estimated)

1112

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

N/A

Sampling Method

Non-Probability Sample

Study Population

The study population consists of adult outpatients (aged >= 18 years) referred to the Department of Clinical Radiology at Assiut University Hospitals, a tertiary healthcare center in Assiut, Egypt, for clinically indicated intravenous contrast-enhanced computed tomography (CE-CT). Eligible participants have documented baseline serum creatinine and eGFR measured within 48 hours prior to contrast exposure. The population excludes patients with end-stage renal disease (CKD stage 5 or chronic dialysis), intravascular iodinated contrast exposure within the preceding 7 days, acute hemodynamic instability, and pregnant or lactating females.

Description

Inclusion Criteria:

  • Adult patients aged 18 years or older referred for clinically indicated outpatient intravenous contrast-enhanced computed tomography (CE-CT) scan.
  • Documented baseline serum creatinine and estimated glomerular filtration rate (eGFR) measured within 48 hours prior to contrast exposure.
  • Provision of written informed consent prior to study enrollment.

Exclusion Criteria:

  • Severe chronic kidney disease (CKD stage 5, baseline eGFR < 15 mL/min/1.73 m2) or currently on chronic renal replacement therapy (hemodialysis or peritoneal dialysis).
  • Exposure to intravascular iodinated contrast media within the preceding 7 days.
  • Hemodynamic instability, acute decompensated heart failure, or cardiogenic shock upon presentation.
  • Pregnant or lactating females.
  • Inability or unwillingness to comply with the 48 to 72-hour follow-up serum creatinine testing.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Contrast-Enhanced CT Cohort
Adult outpatient participants (aged ≥ 18 years) undergoing clinically indicated intravenous contrast-enhanced computed tomography (CE-CT). Participants receive standard-of-care intravenous iodinated contrast media (low-osmolar Iopromide [300 or 370 mg I/mL] or iso-osmolar Iodixanol [320 mg I/mL]) administered via an automated power injector. Baseline renal function (serum creatinine and eGFR) is assessed within 48 hours prior to scan, with renal excretion capacity determined as absolute GFR de-indexed to body surface area using the DuBois formula. Participants undergo follow-up serum creatinine testing at 48 to 72 hours post-contrast exposure to evaluate the incidence of contrast-associated acute kidney injury (CA-AKI) relative to contrast volume and the dynamic contrast volume-to-absolute GFR (CV/GFR_abs) ratio.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of Participants With Contrast-Associated Acute Kidney Injury (CA-AKI)
Time Frame: Baseline
Contrast-associated acute kidney injury (CA-AKI) is defined according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria as an absolute increase in serum creatinine of >= 0.3 mg/dL (>= 26.5 umol/L) within 48 hours, or a relative increase of >= 1.5 times the baseline value. Baseline serum creatinine is collected within 48 hours prior to contrast exposure, and follow-up serum creatinine is measured between 48 and 72 hours following intravenous contrast-enhanced CT.
Baseline

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

October 1, 2026

Primary Completion (Estimated)

October 1, 2027

Study Completion (Estimated)

November 1, 2027

Study Registration Dates

First Submitted

September 6, 2026

First Submitted That Met QC Criteria

September 6, 2026

First Posted (Actual)

September 10, 2026

Study Record Updates

Last Update Posted (Actual)

September 10, 2026

Last Update Submitted That Met QC Criteria

September 6, 2026

Last Verified

September 1, 2026

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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