Rheumatoid meningitis (RM) is a rare but treatable central nervous system (CNS) manifestation of rheumatoid arthritis (RA) with various clinical presentations and atypical cerebrospinal fluid (CSF) findings. There are no established biomarkers for RM, making diagnosis a challenge. Herein, we present three cases of RM: two patients with RA diagnosis and one without. CSF analysis showed pleocytosis in only one case. In contrast, CSF neopterin levels were elevated in all three cases and decreased after steroid therapy. This study suggests that CSF neopterin levels may be a useful biomarker for diagnosing and therapeutically monitoring CNS inflammation in patients with RM.

中文翻译：

---

CSF新蝶呤水平升高的类风湿性脑膜炎3例

类风湿性脑膜炎 (RM) 是类风湿性关节炎 (RA) 的一种罕见但可治疗的中枢神经系统 (CNS) 表现，具有多种临床表现和非典型脑脊液 (CSF) 表现。RM 没有既定的生物标志物，使诊断成为一项挑战。在此，我们介绍了三例 RM：两名诊断为 RA 的患者，一名未诊断。脑脊液分析仅显示一例细胞增多症。相比之下，所有三个病例的脑脊液新蝶呤水平均升高，并在类固醇治疗后降低。这项研究表明，脑脊液新蝶呤水平可能是诊断和治疗监测 RM 患者中枢神经系统炎症的有用生物标志物。