Heavily Scarred Refluxing Renal Units Have Significantly Different Pathologic Features at the Distal End of the Related Ureter Compared to the Ureters of Less Scarred Renal Units

Abstract

Objective: This study aims to describe the pathological features of the distal end of ureters and their correlation with scar formation patterns in the kidney.
Methods: The study includes 83 children (49 male, 34 female), who underwent ureteroneocystostomy (UNC) operations from 2008-2010. The distal end of ureters (approximately 3-4 mm) were resected and 110 ureter specimens from 83 patients were available for pathological examination. The presentation age, clinical presentation pattern, reflux grade and scar patterns on dimercaptosuccinic acid (DMSA) scan were obtained from record and correlation with histopathological findings were investigated. Scar patterns were defined as presence of no scar (NS), diffuse scar (DS) or focal cortical scars (FS). General structural changes were also investigated histopathologically including inflammatory changes graded for intensity (G1-G3), extracellular matrix and smooth muscle content, ureteric diameter and wall thickness.
Results: Histological examination of the ureterorenal units showed that there were 35/110 (33%), 30/110 (27%) and 45/110 (40%) in the NS, DS and FS groups, respectively. When scar rates were investigated by grade of reflux (G1-2 low grade vs. G3-5 high grade reflux) the scar rates were 39.5%and 90.3% respectively. High grade inflammation (G3) was found in 66%, 28.9% and 36.4% in kidneys in the DS, FS and NS scar groups respectively (p<0.05).
Conclusion: This investigation shows that there are significant differences of histologic structure of the distal end of the ureters when they are classified by kidney scarring. There is more intense inflammation, more collagen deposition, less ssmooth muscle content and increased ureteric wall thickness in the ureters of the kidneys with diffuse scar when compared to others with less or no scar. 

Keywords

• Vesicoureteral reflux,kidney scar,ureter

Ağır Skarlı Böbreklerin Üreter Alt Uç Patolojik Özellikleri Az Skarlı Tarafla Karşılaştırıldığında Belirgin Farklılık Göstermektedir

Abstract

Amaç: Bu çalışma, üreterlerin distal ucunun patolojik özelliklerinin böbrekteki skar oluşum patternleri ile olan ilişkisini araştırmayı amaçlamaktadır.
Yöntem: VUR tanısıyla takip edilen ve 2008-2010 yılları arası bilateral ve ünilateral üreteroneosistostomi (UNC) ameliyatı yapılan 83 çocuk hasta (49 erkek, 34 kız) değerlendirildi. UNC yapılan taraf üreter alt ucu rezeke edildi ve 83 hastanın toplam 110 adet üreter alt ucu spesimeni, mevcut klinik ve patolojik bulgularla beraber değerlendirildi. Hasta yaşı, klinik patterni, reflü derecesi, DMSA’ daki skar patterni üreter alt ucu histopatolojik yapısıyla birlikte değerlendirildi. Skar patternleri skarsız, diffüz skar, fokal skar olmak üzere ayırıldı. Histopatolojik değerlendirme sırasında inflamasyon Grade 1-3 olarak derecelendirildi. Ekstrasellüler matriks, düz kas oranı ve üreter çapı ve duvar kalınlığı değerlendirildi.
Bulgular: Toplam 110 üreterorenal ünitenin otuz beşinde (%33) skar yoktu. Otuzunda (%27) diffüz skar ve 45 ünitede (%40) fokal skar tespit edildi. Skar oranları düşük dereceli reflü grubu (G1-2) ve yüksek dereceli reflü grubunda (G3-4-5) sırasıyla %39,5 ve %90,3 olarak bulundu. Skar oranları reflü derecesine (G1-2 düşük vs. G 3-5 yüksek) göre değerlendirildiğinde skar oranları sırasıyla %39,5 ve %90,3 olarak bulundu. İnflamasyonun en yüksek olarak değerlendirildiği grade 3 inflamasyon diffüz skar, fokal skar ve skarın olmadığı grupta sırasıyla %66, %28,9 ve %36,4 olarak bulundu (p<0,05).
Sonuç: Çalışmamızda gruplardaki hastalar skar derecesine göre sınıflandığında üreter alt uç patolojileri arasında belirgin fark gözlenmiştir. Diffüz skarı bulunan grupta inflamasyon fokal skarı bulunan ve skarı bulunmayan gruba göre fazladır. Aynı zamanda bu grupta kollajen miktarının, üreter duvar kalınlığının, inflamasyon şiddetinin fazlalığı görülmüştür. Buna bağlı olduğu düşünülen kollajen depozisyonunun artışı ve mevcut olan düz kas miktarının belirgin olarak azaldığı belirlenmiştir. 

Keywords

• Vezikoüreteral reflü,renal skar,üreter

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