Why Do Patients Develop Proteinuria With Sirolimus? Do We Have the Answer?

Potential hypothetical effects of sirolimus in glomerular and tubulointerstitial disease states, as summarized from experimental and clinical studies reported in the literature. The figure shows a schematic diagram of the nephron, highlighting the podocyte-endothelial-VEGF (vascular endothelial growth factor) axis and the tubular epithelial EGF axis of the nephron. Sirolimus may have detrimental effects when proliferation plays an important regenerative role and there is relative underexpression of EGF, as in acute kidney injury.