Renal tubule dilation may occur from xenobiotic administration, secondary mechanisms, or an unknown pathogenesis (see ) (Figure 2). Dilation may result from direct toxic injury to the tubule epithelium interfering with absorption and secretion (Figure 3). It may also occur secondary to renal ischemia or from prolonged diuresis related to drug administration. Secondary mechanisms of tubule dilation may result from lower urinary tract obstruction, the deposition of tubule crystals, interstitial inflammation and/or fibrosis, and chronic progressive nephropathy (Figure 4). A few dilated tubules may be regarded as normal histologic variation.
Greaves P. 2012. Histopathology of Preclinical Toxicity Studies, 4th ed. Elsevier, Amsterdam, 560.Abstract: http://www.sciencedirect.com/science/book/9780444538567
Lameire N. 2005. The pathophysiology of acute renal failure. Crit Care Clinics 21:197-210.