Tubulointerstitial fibrosis

What it means

A progressive detrimental connective tissue deposition (fibrosis) on the kidney parenchyma involving the tubules and interstitial tissue of the kidney. Tubulointerstitial injury in the kidney is complex, involving a number of independent and overlapping cellular and molecular pathways, with renal interstitial fibrosis and tubular atrophy (IF/TA) as the final common pathway. However, IF and TA are separable, as shown by the profound TA in renal artery stenosis, which characteristically has little or no fibrosis (or inflammation). For new annotations it is preferable to annotate to the specific HPO terms for Renal interstitial fibrosis and/or Renal tubular atrophy.

This finding is usually shown by renal biopsy. Fibrosis involves an excess accumulation of extracellular matrix and usually results in loss of function when normal tissue is replaced with scar tissue. Tubulointerstitial renal fibrosis, characterized as a progressive detrimental connective tissue deposition on the kidney parenchyma, appears to be a harmful process leading inevitably to renal function deterioration, independently of the primary renal disease which causes the original kidney injury. Epithelial to Mesenchymal Transition (EMT) of tubular epithelial cells which are transformed to mesenchymal fibroblasts migrating to adjacent interstitial parenchyma constitutes the principal mechanism of renal fibrosis along with local and circulating cells. (PMID:20011086)

Rare diseases that can present with this4

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Tubulointerstitial renal fibrosis · Tubulointerstitial scarring