Department of Pathology, Indira Gandhi Medical College and Research Institute, PUDUCHERRY, INDIA.
Turk Patoloji Derg. 2021;37(3):212-218. doi: 10.5146/tjpath.2021.01532.
The aim of the study is to do a clinicopathologic study of post mortem kidney biopsies with significant deposition of bilirubin pigment within tubular epithelial cells and in the lumen of distal tubules as a bile cast.
All post mortem specimens with acute tubular necrosis, with the presence of bile casts in tubules or bile pigment deposition in the tubular epithelium during the period 2015-2018 were examined for gross and histopathology along with biochemical parameters and viral markers.
Bile casts with sloughed renal tubular epithelial cells and occasional macrophages were present in the distal convoluted tubule in 78.6% of biopsies (11/14). The plugging of distal convoluted tubule with casts was similar to that seen in myeloma and myoglobin cast nephropathies. Bilirubin pigment deposition was present in 35.7% (5/14) of cases. The frequency of bile casts in each biopsy was variable and it did not have any association with serum bilirubin levels or etiology of liver dysfunction. A striking difference from earlier studies is the high number of toxin-induced liver damage including six cases of paraquat and 2 cases of yellow phosphorus poisoning.
This study proves importance of the bile cast nephropathy as a reason for kidney injury, especially with varied hepatotoxic etiologies, especially paraquat and yellow phosphorus.
本研究旨在对尸检肾活检标本进行临床病理研究，这些标本的肾小管上皮细胞内和远曲小管腔内有大量胆红素色素沉积，表现为胆栓。
在 2015 年至 2018 年期间，所有表现为急性肾小管坏死，且在肾小管中存在胆栓或在肾小管上皮细胞中有胆色素沉积的尸检标本均进行了大体和组织病理学检查，同时检查了生化参数和病毒标志物。
在 78.6%的活检标本（11/14）中，远曲小管中存在脱落的肾小管上皮细胞和偶尔的巨噬细胞形成的胆栓。远曲小管的栓子阻塞类似于骨髓瘤和肌红蛋白尿肾病所见。胆红素色素沉积见于 35.7%（5/14）的病例。每个活检标本中胆栓的频率是不同的，与血清胆红素水平或肝功能障碍的病因无关。与早期研究的显著不同之处在于，毒素引起的肝损伤数量较多，包括 6 例百草枯和 2 例黄磷中毒。
本研究证明了胆栓性肾病作为导致肾损伤的原因的重要性，尤其是与各种肝毒性病因有关，尤其是百草枯和黄磷。
