Renal Histology in CKD Stages: Match or Mismatch with Glomerular Filtration Rate?

A reliable assessment of renal function is of paramount importance in several clinical assets in order to tailor a personalized medical approach. CKD classification system, created in 2002 by the National Kidney Foundation-sponsored Kidney Disease Outcomes Quality Initiative and then implemented in the following years by the K-DIGO guidelines, offered clinicians a new strategy to better identify nephrological patients at low or high risk to develop renal insufficiency, in order to avoid the progression to end-stage renal disease. However, the criteria used to create this classification did not consider some important aspects related to renal histology and glomerular filtration rate measurement, resulting in a possible over- or underestimation of the real established renal damage. In this mini-review, we will summarize the most relevant shortcomings in the CKD classifications, which can create misleading diagnosis in daily clinical practice.