Department of Nephrology, Toho University Faculty of Medicine, Tokyo, Japan.
Department of Nephrology, Toho University Faculty of Medicine, Tokyo, Japan,
Nephron. 2020;144 Suppl 1(Suppl 1):18-27. doi: 10.1159/000512143. Epub 2020 Dec 2.
This study evaluated the clinicopathological findings of acute/active antibody-mediated rejection (AABMR) according to the Banff 2013 classification.
We analyzed 345 biopsies of 269 kidney transplant recipients. Pathological AABMR (PAABMR) was defined as histological evidence of acute tissue injury and endothelial injury by light microscopy regardless of donor-specific antibodies (DSAs).
Among the 345 biopsies, 29 (8.4%) were diagnosed as PAABMR. The mean g score was 1.17 ± 0.60, the mean ptc score was 1.97 ± 1.32, and DSA positivity was found in 69% of PAABMR. The mean duration after transplantation was 22.9 ± 26.7 months. Among 3 groups (DSA-high, mean fluorescence intensity (MFI) ≥ 5,000; DSA-low, MFI < 5,000 to ≥1,000; below cutoff), ABO incompatibility in DSA-high was significantly lower and second transplantation in DSA-high was significantly higher. We found 83% of PAABMR by the protocol biopsy (subclinical AABMR [SAABMR]). The short-term clinical and light microscopical changes in 8 cases of SAABMR did not show worsening during follow-up period (9-24 months). However, ultrastructural finding, including glomerular endothelial swelling, subendothelial electron-lucent widening, and early glomerular basement duplication, were found by electron microscopy (EM) in the first biopsies, and half of the SAABMR cases developed de novo circular peritubular capillary multilayering in the follow-up biopsies.
PAABMR was mainly found by the protocol biopsy. The short-term follow-up of SAABMR patients did not show worsening clinically and light microscopically, but ultrastructural examination by EM was useful to detect early lesions of endothelial injury and progression of glomerular and peritubular capillary basement membrane alterations.
本研究根据 2013 年 Banff 分类评估急性/活跃抗体介导的排斥反应(AABMR)的临床病理发现。
我们分析了 269 例肾移植受者的 345 例活检。通过光镜观察到急性组织损伤和内皮损伤的组织病理学 AABMR(PAABMR)定义为组织学证据,无论供体特异性抗体(DSA)如何。
在 345 例活检中,29 例(8.4%)诊断为 PAABMR。g 评分平均为 1.17±0.60,ptc 评分平均为 1.97±1.32,PAABMR 中 DSA 阳性率为 69%。移植后平均时间为 22.9±26.7 个月。在 3 组(DSA-高,平均荧光强度(MFI)≥5000;DSA-低,MFI<5000 至≥1000;低于临界值)中,DSA-高的 ABO 不相容性明显降低,DSA-高的二次移植明显增加。我们通过方案活检发现 83%的 PAABMR(亚临床 AABMR [SAABMR])。8 例 SAABMR 的短期临床和光镜变化在随访期间(9-24 个月)没有显示恶化。然而,在首次活检中通过电子显微镜(EM)发现了超微结构发现,包括肾小球内皮肿胀、内皮下电子透明增宽和早期肾小球基底膜复制,并且在随访活检中,SAABMR 病例中有一半出现新的环状肾小管周毛细血管多层化。
PAABMR 主要通过方案活检发现。SAABMR 患者的短期随访在临床上和光镜下没有显示恶化,但 EM 的超微结构检查有助于发现内皮损伤的早期病变和肾小球及肾小管周毛细血管基底膜改变的进展。