Department of Connective Tissue Diseases, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.
Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan.
Mod Rheumatol Case Rep. 2022 Jun 24;6(2):209-216. doi: 10.1093/mrcr/rxab042.
Acute encephalitis is an extremely rare condition in primary Sjogren's syndrome (pSS), and its characteristics and prognosis remain unclear. Here, we report the case of pSS presented with acute encephalitis. She was admitted to our hospital for acute disturbance of consciousness. Acute encephalitis was diagnosed based on the results of the cerebrospinal fluid test (the increase of leucocyte counts, proteins, and interleukin-6 levels), magnetic resonance imaging, and single-photon emission computed tomography with 99mTc. The infectious aetiologies and underlying malignancies were excluded. Serum anti-Sjogren's syndrome-related antigen A autoantibody was positive with extremely high titre. The biopsy specimen of her labial salivary gland revealed a focal lymphocytic sialadenitis with a score of grade 4 in the Greenspan grade. She also developed diffuse alveolar haemorrhage during the clinical course. She was diagnosed with pSS complicated with acute encephalitis followed by diffuse alveolar haemorrhage and successfully treated with pulse steroids, high dose of prednisolone and intravenous cyclophosphamide. Our present case and literature review suggest that acute encephalitis associated with pSS can be treatable with the immunosuppressive therapy, and thus early recognition and treatment initiation are important for this life-threatening condition. Thus, pSS should be included in the differential diagnosis of unexplained encephalitis. Notably, our case characteristically showed diffuse alveolar haemorrhage, adding new insights into the pathogenesis of acute encephalitis associated with pSS that capillaritis might be the underlying cause of this condition.
原发性干燥综合征（pSS）并发急性脑炎极为罕见，其特征和预后尚不清楚。在此，我们报告一例以急性脑炎为首发表现的 pSS 病例。患者因急性意识障碍入院，根据脑脊液检查（白细胞计数、蛋白和白细胞介素-6 水平升高）、磁共振成像和 99mTc 单光子发射计算机断层扫描结果诊断为急性脑炎。排除了感染性病因和潜在恶性肿瘤。血清抗干燥综合征相关抗原 A 自身抗体阳性，滴度极高。唇腺活检显示为 4 级格林斯潘分级的局灶性淋巴细胞性唾液腺炎。在病程中还发生了弥漫性肺泡出血。诊断为 pSS 并发急性脑炎、弥漫性肺泡出血，并成功接受了脉冲类固醇、大剂量泼尼松龙和静脉环磷酰胺治疗。本病例及文献复习提示，pSS 相关急性脑炎可通过免疫抑制治疗得以治疗，因此早期识别和治疗启动对这种危及生命的疾病非常重要。因此，pSS 应纳入不明原因脑炎的鉴别诊断。值得注意的是，本病例的特征性表现为弥漫性肺泡出血，为 pSS 相关急性脑炎的发病机制提供了新的见解，毛细血管炎可能是这种疾病的潜在原因。
