Demographics of the three cohorts in this study.

Renal involvement is a common occurrence in subjects with systemic autoimmune diseases. The renal manifestation and its severity depend on the underlying condition and may reversely complicate the clinical course of autoimmune diseases. Renal function markers have been widely used in the assessment of normal functioning of kidneys including glomerular filtration rate and concentrating and diluting capacity of the kidney. An increase or decrease in the values of these markers may indicate kidney dysfunction. In this study, a number of critical renal markers were examined in seropositive autoimmune diseases including systemic lupus erythematosus (SLE), connective tissue disorder (CTD), and rheumatoid arthritis (RA). The data from three cohorts of subjects enrolled in renal markers and autoimmune antibody testing between January 2015 to August 2019 were retrospectively studied. The prevalence of renal markers that were out of the reference range and their average levels in female and male subgroups across SLE, CTD, and RA cohorts were compared and analyzed. The levels of renal markers are significantly affected by the presence of autoantibodies, in particular eGFR, cystatin C, and albumin. Autoantibodies were also more frequent in subjects with severe renal function damage. Close follow-up of both renal markers and autoantibodies may potentially assist in the early diagnosis of kidney diseases and improve the survival and life expectancy of autoimmune patients.

肾脏受累在系统性自身免疫病患者中十分常见。患者的肾脏表现及其严重程度取决于基础疾病，且可反向影响自身免疫病的临床进程。肾功能标志物已被广泛用于评估肾脏正常功能，涵盖肾小球滤过率（glomerular filtration rate, GFR）与肾脏浓缩、稀释功能。此类标志物的数值升高或降低，均可提示肾功能异常。本研究针对血清学阳性的自身免疫病患者展开，涵盖系统性红斑狼疮（systemic lupus erythematosus, SLE）、结缔组织病（connective tissue disorder, CTD）及类风湿关节炎（rheumatoid arthritis, RA）三类疾病，对多种关键肾功能标志物进行了检测。研究回顾性分析了2015年1月至2019年8月期间，参与肾功能标志物检测与自身抗体检测的三类队列受试者的数据，对比并分析了SLE、CTD及RA三类队列中，肾功能标志物超出参考范围的检出率，以及男女亚组的标志物平均水平。研究结果显示，肾功能标志物水平受自身抗体存在情况的显著影响，尤以估算肾小球滤过率（estimated glomerular filtration rate, eGFR）、胱抑素C（cystatin C）与白蛋白（albumin）为甚；合并严重肾功能损伤的患者，自身抗体检出率也更高。对肾功能标志物与自身抗体进行密切随访监测，或可助力肾脏疾病的早期诊断，并改善自身免疫病患者的生存质量与预期寿命。