Aim: To identify metabolite markers in the kidney cortex of patients with chronic kidney disease (CKD) using in vivo 1H magnetic resonance spectroscopy (1H-), and correlate these with existing markers of disease (serum creatinine, proteinuria).

Background: The appearance of interstitial fibrosis is common to all for of CKD and is one of the best predictors of disease progression. The current standard for fibrosis measurement involves invasive needle biopsy which introduces risk to the patient. With continuing advancement in the field of magnetic resonance, in vivo 1H-Nspectroscopy can be applied as a clinical tool for assessing metabolic aberrations in tissues non-invasively.

Methods: We had identified metabolite alterations in an adenine diet-induced CKD mouse model ex vivo by 1H-. These included creatine, choline, and mobile lipids. In patients, similar changes were sought in the kidneys of healthy people and CKD patients using 1H-. A single voxel spectroscopy package utilising point resolved spectroscopy (Siemens) was used, including respiratory triggering techniques to cater for respiratory cycle movement of the kidney. Spectra were processed and analysed using MestReNova software (Mestrelabs).

Results: The 1H- protocol was established and validated by our group using a 3 T clinical scanner and a 90 channel body coil. The region of interest (voxel) placement in the inferior pole with volume 3.38 cm3 reduces lipid contamination (from renal sinus and perinephric fat). High reproducibility was found in the same individuals at different timepoints. Kidneys of live kidney donors (baseline) and patients with CKD are being assessed using this technology as part of the DISCERN-CKD study.

Conclusions: In vivo human 1H- may provide a non-invasive means to evaluate fibrosis in the kidneys.