La Céline, Smet Julie, Nagant Carole, Soyfoo Muhammad
Department of Rheumatology, Hôpital Erasme, Hôpital Universitaire de Bruxelles (HUB), 1070 Bruxelles, Belgium.
Laboratory of Immunology, Laboratoire Hospitalier Universitaire de Bruxelles, Université Libre de Bruxelles (LHUB-ULB), 1020 Bruxelles, Belgium.
Int J Mol Sci. 2025 Aug 1;26(15):7433. doi: 10.3390/ijms26157433.
Anti-Ku antibodies are rare autoantibodies associated with connective tissue diseases (CTDs), but their clinical significance remains poorly understood due to limited studies. Semi-quantitative immunodot assays yield positive, negative, or borderline results, with the clinical relevance of borderline findings remaining unclear. The purpose of this study is to characterize the clinical spectrum of anti-Ku-positive patients and evaluate the clinical significance of anti-Ku-borderline results in CTD management. A retrospective cohort study was conducted at Hôpital Erasme, including all patients with anti-Ku-positive or borderline results, over a 10-year period. Clinical and biological data were collected from medical records and analyzed for disease associations, organ involvement, and outcomes. Among 47 anti-Ku-positive patients, systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS) were the most common diagnoses. Interstitial lung disease (ILD) occurred in 23.4% and renal involvement in 12.8% of patients. Cytopenia was significantly associated with glomerulonephritis. Organ damage, particularly pulmonary and renal involvement, correlated with increased mortality. In the borderline group (n = 33), SLE and SS remained the predominant diagnoses. During follow-up, three patients died (all with isolated ILD without associated CTD), one required chronic dialysis, and one underwent lung transplantation. ILD was present in 7/22 (31.8%) borderline patients, and renal involvement in 7/32 (21.9%). This study demonstrates significant associations between anti-Ku antibodies and organ damage, with increased mortality risk. The high prevalence of pulmonary and renal involvement in anti-Ku-borderline patients suggests that these results carry substantial clinical significance and should prompt comprehensive CTD evaluation. These findings support treating borderline anti-Ku results with the same clinical vigilance as positive results, given their similar association with severe organ involvement and adverse outcomes.
抗Ku抗体是与结缔组织病（CTD）相关的罕见自身抗体，但由于研究有限，其临床意义仍未得到充分了解。半定量免疫斑点试验结果可为阳性、阴性或临界值，而临界值结果的临床相关性仍不明确。本研究旨在描述抗Ku阳性患者的临床谱，并评估抗Ku临界值结果在CTD管理中的临床意义。在伊拉斯谟医院进行了一项回顾性队列研究，纳入了10年间所有抗Ku阳性或临界值结果的患者。从病历中收集临床和生物学数据，并分析疾病关联、器官受累情况及预后。在47例抗Ku阳性患者中，系统性红斑狼疮（SLE）和干燥综合征（SS）是最常见的诊断。23.4%的患者出现间质性肺病（ILD），12.8%的患者有肾脏受累。血细胞减少与肾小球肾炎显著相关。器官损害，尤其是肺部和肾脏受累，与死亡率增加相关。在临界值组（n = 33）中，SLE和SS仍然是主要诊断。随访期间，3例患者死亡（均为孤立性ILD，无相关CTD），1例需要长期透析，1例接受了肺移植。22例临界值患者中有7例（31.8%）存在ILD，32例中有7例（21.9%）有肾脏受累。本研究表明抗Ku抗体与器官损害之间存在显著关联，死亡风险增加。抗Ku临界值患者中肺部和肾脏受累的高发生率表明这些结果具有重要的临床意义，应促使进行全面的CTD评估。鉴于临界值抗Ku结果与严重器官受累和不良结局的相似关联，这些发现支持对其进行与阳性结果相同的临床监测。
