MRI-detectable nanoparticles: the potential role in the diagnosis of and therapy for chronic kidney disease.

Chronic kidney disease (CKD) is a common, deadly, and expensive threat to public health. Patients susceptible to the development of CKD are difficult to identify because there are few noninvasive clinical techniques and markers to assess early kidney dysfunction. Noninvasive imaging techniques are being developed to quantitatively measure kidney morphology and function in preclinical research and in clinical trials. Magnetic resonance imaging (MRI) techniques in particular have the potential to provide structural and functional information in the kidney. Novel molecular imaging techniques, using targeted magnetic nanoparticles that exploit the characteristics of the endogenous protein, ferritin, have been developed in conjunction with MRI to count every perfused glomerulus in the kidney and measure their individual volumes. This technique could open the door to the possibility of prospectively assessing and eventually reducing a patient's risk for progression to CKD. This review highlights the potential clinical benefits of early detection in patients predisposed to CKD and discusses technologic and regulatory hurdles to the translation of these molecular MRI techniques to provide early diagnosis of CKD.