Shear Wave Elastography in Native Kidney Disease

The proposed project is a prospective cross-sectional study correlating native kidney shear
wave elastography (SWE) measurements with histology. Briefly, patients referred for a native
kidney biopsy will undergo SWE and the shear wave velocity (SWV) will be correlated with
degree of fibrosis determined by a pathologist.

A list of patients who recently underwent a native kidney biopsy will be obtained from the
pathology department on a weekly basis. Patients will then be contacted about participating
in the study and consented during a follow up visit with their nephrologist.

After their biopsies, patients will be scheduled to come for a renal ultrasound and SWE. SWE
examination will be conducted using an ultrasound machine equipped with a Philips Epiq ARFI
Shear wave ElastPQ C1-5 mHz transducer. Shear wave velocity will be obtained and an estimate
of tissue elasticity (Young's modulus) will be calculated. All measurements will be performed
by one of two qualified radiology physicians who will be blinded to the clinical and
pathological data. We will allow a period of 90 days to obtain the images after the biopsy;
otherwise the patient is no longer eligible to participate.

The primary outcome measure of this study is to determine whether tissue elasticity
determined by SWE can assess kidney fibrosis. Linear regression analysis will be performed to
describe the relation of the extent of fibrosis and parenchymal stiffness.

Inclusion Criteria:

- All patients over 18 years of age who are referred for a native kidney biopsy.

Exclusion Criteria:

- BMI > 35

- Patients with polycystic kidney disease, renal cell carcinoma, hydronephrosis or renal
stones.

- Patients who develop severe post biopsy complications (infection, significant bleeding
requiring transfusion or intervention)

- Pregnant patients.