全身性硬化症重疊全身性紅斑性狼瘡的病人其臨床表現、治療成效及預後之評估

Evaluation of the clinical presentation, treatment and prognosis of systemic sclerosis and systemic lupus erythematosus overlap patients

目的：探討全身性硬化症重疊全身性紅斑性狼瘡的病人其臨床表現、治療成效以及預後與全身性硬化症病人之差異，並且進行相關之文獻回顧。方法：本研究納入最近十年內，所有曾於台大醫院就醫，病歷有確認為全身性硬化症的病人。將其中同時符合全身性硬化症以及全身性紅斑性狼瘡的病人與全身性硬化症病人互相比較。結果：這個單一中心的研究一共收錄57個全身性硬化症病人。其中33（57.89%）人屬於全身性硬化症控制組，其餘24（42.11%）人屬於全身性硬化症重疊症。當中有16人（所有全身性硬化症的28.07%）屬於全身性硬化症重疊全身性紅斑性狼瘡。全身性硬化症重疊全身性紅斑性狼瘡的病人顯著比全身性硬化症病人普遍有IgG高，C4低與有抗體對抗dsDNA、histone、Jo1、RNP、SSA、SS or Sm（p<0.05）。多變項邏輯回歸統計顯示出女性性別以及C4低會增加全身性硬化症重疊全身性紅斑性狼瘡之風險。另外，全身性硬化症重疊全身性紅斑性狼瘡患者的anti-Scl 70 抗體效價顯著比全身性硬化症患者高（平均值 365.4 vs. 339.5, p<0.001），這可表示當全身性紅斑性狼瘡的病人出現高效價的anti-Scl 70 抗體時，要注意重疊全身性硬化症的可能性。結論：C4低、IgG高、抗dsDNA抗體或其他抗可萃取式核抗原抗體以及高效價的anti-Scl 70 抗體可能跟全身性硬化症重疊全身性紅斑性狼瘡的表現相關。

Objective: To analyze the clinical characteristics, laboratory findings, treatment and prognosis of systemic sclerosis (SSc) and systemic lupus erythematosus (SLE) overlap patients in comparison to patients with SSc alone in a medical center in northern Taiwan, and to perform a literature review on this topic. Methods: We retrospectively examined the electronic medical records of all patients with SSc from December 2002 to November 2012. Patients fulfilling the classification criteria for both SSc and SLE were identified and compared to the SSc patients. Results: A total 57 SSc patients were collected; 33 (57.89%) in the SSc control group and 24 (42.11%) in the SSc overlap syndrome group. Of the 24 patients in the overlap group, 16 had SSc and SLE overlap syndrome (16/57, 28.07%). Elevated IgG, low C4, and positive antibody against dsDNA, histone, Jo1, RNP, SSA, SSB, or Sm were more common in the SSc and SLE overlap group compared to the SSc control group (p<0.05). Multivariate logistic regression demonstrated that female gender and low C4 incurred an increased risk of an association with SSc and SLE overlap syndrome. Moreover, the SSc overlap patients had significant higher titers of anti-Scl 70 compared to the SSc controls (mean value: 365.4 vs. 339.5, p<0.001), suggesting that overlap with SSc should be considered in SLE patients with higher titers of anti-Scl 70. Conclusion: Low C4, elevated IgG, positive anti-dsDNA antibody or positive antibody against various extractable nuclear antigen, and high titers of anti-Scl 70 antibody suggest SSc and SLE overlap syndrome.