背景:抗氨酰基-tRNA合成酶(抗ARS)抗体是肌炎特异性自身抗体,已在不存在皮肌炎或多发性肌炎的间质性肺炎患者亚组中鉴定。抗ARS抗体阳性间质性肺炎通常用类固醇或免疫抑制剂治疗,通常对这些疗法有反应。这里,我们详细介绍了一例被诊断为抗ARS抗体阳性的间质性肺炎患者因接受类固醇和免疫抑制剂治疗而加重呼吸衰竭的病例.进一步检查显示该患者误诊,随后诊断为自身免疫性肺泡蛋白沉积症。
方法:一名66岁男子因劳累呼吸困难到医院就诊,导致间质性肺炎的检测。检测到血清抗ARS抗体;然而,没有其他提示肌炎的发现.根据血清KL-6的显着增加和胸部计算机断层扫描结果,怀疑肺泡蛋白沉积症(PAP)。支气管肺泡灌洗显示灌洗液没有乳状变化。在用类固醇治疗并开始使用免疫抑制剂治疗抗ARS抗体阳性间质性肺炎后,呼吸衰竭和胸部影像学检查结果显示病情恶化.反复进行支气管镜检查,收集乳样肺泡灌洗液;鉴定血清抗粒细胞巨噬细胞集落刺激因子抗体。类固醇和免疫抑制剂逐渐减量和停药,在全身麻醉下反复肺泡灌洗后,患者病情稳定。
结论:由于类似的表述,PAP可误诊为间质性肺炎。如果免疫抑制治疗加剧了间质性肺炎引起的肺部病变,医师应重新考虑诊断,并将PAP纳入鉴别诊断.
BACKGROUND: Anti-aminoacyl-tRNA synthetase (anti-ARS) antibodies are myositis-specific autoantibodies that have been identified in a subset of patients with interstitial pneumonia who do not present with dermatomyositis or polymyositis. Anti-ARS antibody-positive interstitial pneumonia is commonly treated with steroids or immunosuppressive agents and is usually responsive to these therapies. Here, we present in detail a
case in which respiratory failure of a patient diagnosed with anti-ARS antibody-positive interstitial pneumonia was exacerbated by treatment with steroids and immunosuppressive agents. Further examination revealed misdiagnosis of this patient and a subsequent diagnosis of autoimmune pulmonary alveolar proteinosis.
METHODS: A 66-year-old man presented to the hospital with dyspnea on exertion, which resulted in the detection of interstitial pneumonia. Serum anti-ARS antibodies were detected; however, there were no other findings suggestive of myositis. Pulmonary alveolar proteinosis (PAP) was suspected based on the marked increase in serum KL-6 and chest computed tomography findings. The bronchoalveolar lavage revealed no milky changes in the lavage fluid. After treatment with steroids and initiation of immunosuppressive agents for anti-ARS antibody-positive interstitial pneumonia, respiratory failure and chest imaging findings showed worsening of the condition. Bronchoscopy was repeated, and milk-like alveolar lavage fluid was collected; serum anti-granulocyte macrophage colony-stimulating factor antibody was identified. Steroids and immunosuppressive agents were gradually tapered and discontinued, and the patient\'s condition stabilized after repeated alveolar lavage under general anesthesia.
CONCLUSIONS: Due to similar presentation, PAP can be misdiagnosed as interstitial pneumonia. If pulmonary lesions due to interstitial pneumonia are exacerbated by immunosuppressive treatment, physicians should reconsider the diagnosis and include PAP in the differential diagnosis.