Primary Sjogren's syndrome (pSS) is an autoimmune disorder in which lymphocytic infiltration leads to lacrimal and salivary glands dysfunction, which results in symptoms of dryness (xerophthalmia and xerostomia). Extraglandular features are common and may affect several organs. Renal involvement has long been known as one of the systemic complications of pSS. The most classical lesion observed in pSS is tubulointerstitial nephritis (TIN) and less frequently membranoproliferative glomerulonephritis (MPGN), which is related to cryoglobulinemia. In some cases, renal biopsy is necessary for the definitive diagnosis of kidney involvement. Patients may present with proximal renal tubular acidosis, distal renal tubular acidosis and chronic kidney disease. Response to treatment is usually favorable. However, occasionally severe and rarely lethal outcomes have been described. Recently, several case series and cross-sectional studies have been published which investigated the factors associated with renal involvement in pSS and the most accurate screening tests for early detection. The presence of xerophthalmia, anti-SSA and rheumatoid factor positivity, low C3 levels and other features have all shown either positive or inverse associations with the development of renal complications. Serum creatinine, alpha-1-microglobulin, cystatin-C have been evaluated as early detection biomarkers with variable accuracy. More advanced techniques may be necessary to confirm proximal and distal renal tubular acidosis, along with nephrogenic diabetes insipidus. The aim of the current paper is to summarize and critically examine these findings in order to provide updated guidance on serum biomarkers and further testing for kidney involvement in pSS.

原发性干燥综合征（pSS）是一种自身免疫性疾病，其中淋巴细胞浸润导致泪腺和唾液腺功能障碍，从而导致干燥症状（干眼症和干口症）。腺外特征很常见，可能会影响多个器官。长期以来，肾脏受累一直是pSS的全身并发症之一。在pSS中观察到的最典型的病变是肾小管间质性肾炎（TIN），而膜性肺炎性肾小球肾炎（MPGN）较少见，这与冰球蛋白血症有关。在某些情况下，必须进行肾活检才能明确诊断出肾脏受累。患者可能出现近端肾小管酸中毒，远端肾小管酸中毒和慢性肾脏疾病。对治疗的反应通常是有利的。然而，偶尔会出现严重而致命的结果。最近，已经发表了一些病例系列研究和横断面研究，这些研究调查了与pSS中肾脏受累相关的因素以及用于早期发现的最准确的筛查测试。干眼症，抗SSA和类风湿因子阳性，低C3水平和其他特征的存在均与肾脏并发症的发生呈正相关或反相关。血清肌酐，α-1-微球蛋白，胱抑素-C已作为早期检测生物标志物进行了评估，准确性不同。可能需要更先进的技术来确认近端和远端肾小管酸中毒以及肾病性尿崩症。