Didem TURGUT, Aysel ÇOLAK, Simal KÖKSAL CEVHER, Ezgi COŞKUN YENİGÜN, Fatih DEDE

Measurement of Glomerular Area in Primary Glomerular Diseases With a Digital Pathology Software

Objective: Kidney biopsy is essential to evaluate the activity of underlying kidney disease and the risk factors related to kidney disease progression. Glomerular morphometry is a simple but uncommonly used qualitative predictor of longterm kidney function. But it is mysterious if glomerular morphometry changes due to underlying glomerulonephritis. Measurement quantification is also necessary for reliable interpretation. We aimed to evaluate glomerular morphometry with glomerular area measurements quantitatively with digitally scanned slides in the primary glomerular diseases. Methods: We retrospectively analyzed 198 patients with nephrotic syndrome that underwent kidney biopsy between 2017 and 2019. 48 patients enrolled into the study after the exclusion criteria. We measured the glomerular area as maximum, minimum, and mean areas, using image analysis software. Results: Forty-eight kidney biopsies were analyzed retrospectively under three primary glomerular disease groups as IgA nephropathy (37.5%), focal segmental glomerulosclerosis (29.2%), and membranous glomerulonephritis (33.3%). The glomerular area measured as maximum, minimum, and mean, were similar between 3 groups. The maximum glomerular area was negatively correlated with serum albumin and positively correlated with 24hr proteinuria (r= - 0.592, p=0.044, and r=0.531, p=0.022) at the time of diagnosis. At the end of one year, maximum glomerular area was positively correlated with serum creatinine (r=0.385, p=0.019) and negatively correlated with eGFR (r= - 0.493, p=0.043). Conclusions: At the time of diagnosis of glomerular diseases, maximum glomerular area measurement during the pathological assessment might be an additional marker to estimate the ultrastructure of the kidney and the clinical course of the disease.

Primer Glomerülonefritlerde Glomerül Alanın Dijital Patoloji Yazılımı ile Değerlendirilmesi

Giriş: Böbrek biyopsisi, altta yatan böbrek hastalığını ve progresyona sebep olabilecek risk faktörlerini belirlemek için gereklidir. Glomerüler morfometri basit ancak kullanılmayan, uzun dönem böbrek fonksiyonları hakkında nitel bilgi veren bir yöntemdir. Ancak altta yatan glomerülonefrit tipine göre glomerüler morfometrinin değişip değişmediği bilinmemektedir. Güvenilir değerlendirme için de ölçümlerin standart olması gereklidir. Biz bu çalışmada, primer glomerüler hastalıklarda glomerül morfometresini dijital ortamda, standart bir şekilde, glomerüler alan ölçerek değerlendirmeyi hedefledik. Yöntemler: 2017-2019 yılları arasında nefrotik sendrom tanısı ile böbrek biyopsisi yapılmış 198 hasta restrospektif olarak değerlendirildi. Dışlama kriterleri sonrasında 48 hasta çalışmaya dahil edildi. Glomerül alanı, maksimum, minimum ve ortalama alan ölçümü olarak bilgisayar programı kullanılarak tüm seri kesitlerde incelendi. Bulgular: Kırksekiz böbrek biyopsinde, % 37,5 hastada IgA nefropatisi, % 33,3 memranöz glomerulonefrit, % 29,2 hastada fokal segmental glomeruloskleroz tespit edildi. Üç grup arasında maksimum, minimum ve ortalama glomerül alanları benzerdi. Maksimum glomerül alanı tanı anındaki serum albumin ile negatif, 24 saatlik idrar protein miktarı ile pozitif korele bulundu (r= - 0,592, p=0,044 ve r=0,531, p=0,022). Tedavi sonrası birinci yılda, maksimum glomerül alanı serum kreatinin ile pozitif (r=0.385, p=0.019), GFR ile negatif korele bulundu (r=0,493, p=0,043). Sonuç: Glomerüler hastalıklarda tanı anındaki patolojik değerlendirmede maksimum glomerül alan ölçülmesi, böbreğin altyapısı ve hastalığın klinik gidişatı hakkında tahminde bulunmak için ek belirteç olabilir.

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