Prognostic Implications of a Morphometric Evaluation for Chronic Changes on All Diagnostic Native Kidney Biopsies
Denic, Aleksandar; Bogojevic, Marija; Mullan, Aidan F.; Sabov, Moldovan; Asghar, Muhammad S.; Sethi, Sanjeev; Smith, Maxwell L.; Fervenza, Fernando C.; Glassock, Richard J.; Hommos, Musab S.; Rule, Andrew D.
JASN October 2022, 33 (10) 1927-1941; DOI: https://doi.org/10.1681/ASN.2022030234
Chronic damage as assessed in the kidney biopsy is an independent predictor of renal function decline (doi: 10.1681/ASN.2017121260, doi: 10.1681/ASN.2021010044). Different grading systems for chronicity have been published: some are diagnosis-specific, others can be used regardless of disease etiology.
The success of histologic grading schemes partly depends on ease-of-use; too detailed or time-intensive systems generally do not make it to diagnostic practice. In a recent study published in JASN, the authors examine a morphometry-based approach (with quantification of chronicity parameters assisted by software) to a standard, commonly used ‘eyeballing’ or visual estimation approach based on glomerulosclerosis, interstitial fibrosis/ tubular atrophy (IFTA) and arteriosclerosis (DOI: 10.1016/j.kint.2017.01.002). The study population consisted of a historical cohort of 353 biopsies with follow-up data, making evaluation on hard end points possible (namely, evolution to end-stage kidney disease or progressive chronic kidney disease, respectively emerging in 21% and 44% of patients, over a median follow-up of 7.5 years). Interestingly, morphometry for the above-described features did not substantially differ in predicting outcomes compared to eyeballing.
Additionally, the authors took the opportunity to examine less ‘classical’ measures of chronicity such as IFTA foci density and arteriolar hyalinosis by morphometry. A ten-point score using percentage of glomerulosclerosis, percentage of IFTA, IFTA foci density and arteriolar hyalinosis showed a superior performance. In the discussion, the authors hypothesize that this actually reflects pathogenesis of chronic damage better. The authors also claim they will work on translating this into a new visual estimation approach and as such, close the circle.
Blogged by Amélie Dendooven