Department of Nephrology, Tokyo Medical University Ibaraki Medical Center, Ami 300-0395, Ibaraki, Japan.
Emeritus Professor, University of Tsukuba, Tsukuba 305-8577, Ibaraki, Japan.
Int J Mol Sci. 2022 Jul 5;23(13):7482. doi: 10.3390/ijms23137482.
Since 1995, when we reported the case of a patient with glomerulonephritis with IgA deposition that occurred after a methicillin-resistant (MRSA) infection, many reports of MRSA infection-associated glomerulonephritis have accumulated. This disease is being systematized as Staphylococcus infection-associated glomerulonephritis (SAGN) in light of the apparent cause of infection, and as immunoglobulin A-dominant deposition infection-related glomerulonephritis (IgA-IRGN) in light of its histopathology. This glomerulonephritis usually presents as rapidly progressive glomerulonephritis or acute kidney injury with various degrees of proteinuria and microscopic hematuria along with an ongoing infection. Its renal pathology has shown several types of mesangial and/or endocapillary proliferative glomerulonephritis with various degrees of crescent formation and tubulointerstitial nephritis. IgA, IgG, and C staining in the mesangium and along the glomerular capillary walls have been observed on immunofluorescence examinations. A marked activation of T cells, an increase in specific variable regions of the T-cell receptor β-chain-positive cells, hypercytokinemia, and increased polyclonal immune complexes have also been observed in this glomerulonephritis. In the development of this disease, staphylococcal enterotoxin may be involved as a superantigen, but further investigations are needed to clarify the mechanisms underlying this disease. Here, we review 336 cases of IgA-IRGN and 218 cases of SAGN.
自 1995 年我们报道了首例金葡菌感染相关性肾炎（MRSA 感染后发生的肾小球肾炎）以来，已有大量关于耐甲氧西林金黄色葡萄球菌（MRSA）感染相关性肾炎的报道。根据明确的感染病因，该疾病被系统地归类为葡萄球菌感染相关性肾炎（SAGN），根据其组织病理学特征，被归类为免疫球蛋白 A 占优势沉积感染相关性肾小球肾炎（IgA-IRGN）。这种肾小球肾炎通常表现为急进性肾小球肾炎或急性肾损伤，伴有不同程度的蛋白尿和镜下血尿，以及持续的感染。其肾脏病理表现为多种程度的新月体形成和肾小管间质肾炎的系膜和/或内皮下增生性肾小球肾炎。免疫荧光检查可见系膜和肾小球毛细血管壁IgA、IgG 和 C 染色。在这种肾小球肾炎中，还观察到 T 细胞的显著活化、T 细胞受体β链阳性细胞的特定可变区增加、高细胞因子血症和多克隆免疫复合物增加。在疾病的发展过程中，葡萄球菌肠毒素可能作为超抗原参与，但需要进一步研究来阐明该疾病的发病机制。在此，我们回顾了 336 例 IgA-IRGN 和 218 例 SAGN。
