Trimarchi Hernán, Canzonieri Romina, Schiel Amalia, Costales-Collaguazo Cristian, Stern Aníbal, Paulero Matías, Rengel Tatiana, Andrews José, Iotti Alejandro, Forrester Mariano, Lombi Fernando, Pomeranz Vanesa, Iriarte Romina, Muryan Alexis, Zotta Elsa
Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires, Argentina.
Central Laboratory, Hospital Británico de Buenos Aires, Buenos Aires, Argentina.
Nephron Extra. 2017 May 16;7(2):52-61. doi: 10.1159/000473888. eCollection 2017 May-Aug.
Podocyturia may determine the evolution to podocytopenia, glomerulosclerosis, and renal failure. According to the Oxford classification of IgA nephropathy (IgAN), the S1 lesion describes glomerulosclerosis. Urokinase-type plasminogen activator receptor (uPAR) participates in podocyte attachment, while CD80 increases in glomerulosclerosis. We measured uPAR-positive urinary podocytes and urinary CD80 (uCD80) in controls and in IgAN subjects with M1E0S0T0 and M1E0S1T0 Oxford scores to assess a potential association between podocyturia, inflammation, and glomerulosclerosis.
The groups were as follows: controls (G1), = 20 and IgAN group (G2), = 39, subdivided into M1E0S0T0 (G2A), = 21 and M1E0S1T0 (G2B), = 18. Among the included variables, we determined uPAR-positive podocytes/gram of urinary creatinine (gUrCr) and uCD80 ng/gUrCr. Biopsies with interstitial fibrosis and tubular atrophy <10% were included.
Groups were not different in age and gender; urinary protein-creatinine (uP/C) ratio, Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation, uPAR-positive podocytes/gUrCr, and uCD80 were significantly increased in G2 versus G1. G2A and G2B were not different in age, gender, hypertension, and follow-up. G2B displayed significantly higher uP/C, uPAR-positive podocytes, uCD80, and lower CKD-EPI versus G2A. Strong significant correlations were encountered between uCD80 and podocyturia in G2A and G2B. However, when G1 was compared to G2A and G2B separately, the differences with respect to uP/C, uPAR-positive podocytes, and podocyturia were significantly stronger versus G2B than versus G2A.
IgAN presents elevated uCD80 excretion and uPAR-positive podocyturia, while CD80 correlates with podocyturia. Glomerulosclerosis (S1) at the time of biopsy is associated with higher uP/C, lower renal function, increased uPAR-positive podocyturia, and CD80 excretion, and is independent of M1. In IgAN, uPAR may participate in podocyte detachment.
足细胞尿可能决定向足细胞减少、肾小球硬化和肾衰竭的进展。根据IgA肾病（IgAN）的牛津分类，S1病变描述的是肾小球硬化。尿激酶型纤溶酶原激活物受体（uPAR）参与足细胞黏附，而CD80在肾小球硬化时增加。我们测量了对照组以及牛津病理分级为M1E0S0T0和M1E0S1T0的IgAN患者尿中uPAR阳性足细胞和尿CD80（uCD80）水平，以评估足细胞尿、炎症和肾小球硬化之间的潜在关联。
分组如下：对照组（G1），n = 20；IgAN组（G2），n = 39，再细分为M1E0S0T0（G2A），n = 21和M1E0S1T0（G2B），n = 18。在纳入的变量中，我们测定了每克尿肌酐（gUrCr）中uPAR阳性足细胞数以及每克gUrCr中uCD80的含量。纳入间质纤维化和肾小管萎缩＜10%的肾活检标本。
各组在年龄和性别方面无差异；与G1组相比，G组的尿蛋白肌酐（uP/C）比值、慢性肾脏病流行病学合作组（CKD-EPI）公式估算值中的肾小球滤过率、每克gUrCr中uPAR阳性足细胞数和uCD80均显著升高。G2A组和G2B组在年龄、性别、高血压和随访情况方面无差异。与G2A组相比，G2B组的uP/C、uPAR阳性足细胞数、uCD80显著更高，而CKD-EPI公式估算值中的肾小球滤过率更低。G2A组和G2B组中uCD80与足细胞尿之间存在强显著相关性。然而，当分别将G1组与G2A组和G2B组比较时，与G2B组相比，G1组在uP/C比值、uPAR阳性足细胞数和足细胞尿方面的差异显著更强。
IgAN患者尿中uCD80排泄量和uPAR阳性足细胞尿增加，而CD80与足细胞尿相关。肾活检时的肾小球硬化（S1）与更高的uP/C比值、更低的肾功能、增加的uPAR阳性足细胞尿和CD80排泄相关，且独立于M1。在IgAN中，uPAR可能参与足细胞脱离。
