# Diffusion-Weighted Magnetic Resonance Imaging and Apparent Diffusion Coefficient Mapping Detect Kidney Infiltration in Acute Myeloid Leukemia: A Case Report

## TL;DR

A case report shows how MRI techniques can detect kidney infiltration by leukemia cells, which is rare and hard to diagnose with standard methods.

## Contribution

This is the first reported case of kidney infiltration in AML detected using diffusion-weighted MRI and apparent diffusion coefficient mapping.

## Key findings

- MRI detected blast cell infiltration in the kidneys despite normal CT results.
- Venetoclax and azacitidine therapy led to rapid improvement in AML and kidney function.
- Diffusion-weighted imaging and ADC mapping are valuable for diagnosing rare kidney infiltration in AML.

## Abstract

We describe a case of 70-year-old man with type 2 diabetes and myelodysplastic syndrome progressing to acute myeloid leukemia (AML) who presented with rapidly worsening kidney function. Although computed tomography imaging of the patient’s kidneys was unremarkable, subsequent magnetic resonance imaging (MRI) showed high signal intensity on diffusion-weighted imaging and low signal intensity on the apparent diffusion coefficient map in the kidneys. A kidney biopsy from the region that exhibited abnormal findings on MRI showed blast cell infiltration within the kidney capsule and proximal tubules. After initiating venetoclax and azacitidine therapy, the patient’s AML promptly improved, and his kidney function rapidly recovered. Kidney infiltration in AML is rare and difficult to diagnose because of nonspecific symptoms and the limited sensitivity of plain computed tomography. This case highlights the value of MRI, especially diffusion-weighted imaging and apparent diffusion coefficient mapping, for the detection of blast cell infiltration in the kidneys. To our knowledge, this is the first case in which kidney infiltration was identified in a patient with AML based on imaging findings. This case supports the consideration of MRI as a noninvasive diagnostic tool in patients with unexplained kidney dysfunction and hematologic malignancies.