Department of Medicine, Central Finland Central Hospital, Jyväskylä.
Terveystalo Healthcare, Lappeenranta, Finland.
Rheumatology (Oxford). 2021 May 14;60(5):2391-2395. doi: 10.1093/rheumatology/keaa623.
The classification of seronegative arthritides can be challenging. Our aim was to examine the incidence of SpA diagnosis among patients initially diagnosed as seronegative RA.
Using nationwide Finnish registers from social insurance institutions, we identified all adult patients who were diagnosed with incident seronegative RA [International Classification of Diseases (ICD)-10 code M06] from 1 January 2000 to 31 December 2014. The patients whose diagnoses subsequently changed to the ICD-10 codes of SpA (M07, M45, M46, K50 and K51) were identified in the national care register, until 31 December 2016.
A total of 9784 adult seronegative RA patients were identified. Of these, 564 patients had their diagnosis subsequently changed to SpA: 275 (48.7%) patients with PsA, 245 (43.4%) patients with axial SpA and 44 (7.8%) patients with diagnoses related to IBD. The cumulative incidence of SpA diagnoses in 15 years was 10.4% (95% CI 8.9, 12.1) and 8.1% (95% CI 7.1, 9.3) in men and women, respectively.
This study calls for vigilance in seronegative RA patients, especially those with more atypical presentations, since the diagnosis could change. The possibility of SpA diagnosis should be considered and specifically looked for, as this could impact on management and response to treatment.
血清阴性关节炎的分类具有一定挑战性。本研究旨在探讨最初诊断为血清阴性类风湿关节炎（RA）患者中，脊柱关节炎（SpA）诊断的发生率。
我们利用全国性芬兰社会保险机构的登记数据，确定了所有在 2000 年 1 月 1 日至 2014 年 12 月 31 日期间被诊断为新发血清阴性 RA（国际疾病分类第 10 版[ICD-10]M06 编码）的成年患者。在全国护理登记处，我们确定了随后被诊断为 SpA（ICD-10 编码 M07、M45、M46、K50 和 K51）的患者。随访截止日期为 2016 年 12 月 31 日。
共确定了 9784 例成人血清阴性 RA 患者。其中，564 例患者的诊断随后更改为 SpA：275 例（48.7%）患者为银屑病关节炎，245 例（43.4%）患者为中轴型 SpA，44 例（7.8%）患者为与 IBD 相关的诊断。15 年内 SpA 诊断的累积发生率为 10.4%（95%CI 8.9，12.1），男性和女性分别为 8.1%（95%CI 7.1，9.3）。
本研究提示应密切监测血清阴性 RA 患者，尤其是那些表现不典型的患者，因为其诊断可能发生改变。应考虑 SpA 诊断的可能性，并专门进行检查，因为这可能影响管理和治疗反应。
