運用超音波早期診斷痛風於無症狀高尿酸血症病患

Ultrasound for early diagnosis of gout in patients with asymptomatic hyperuricemia

目的：痛風和高尿酸血症與多重器官損傷、代謝症候群、心血管疾病，和慢性腎臟疾病等相關聯。目前的證據仍不足以建議如何早期診斷痛風及治療無症狀高尿酸血症患者。肌肉骨骼超音波可探測痛風石沉積，軟骨異常，關節積液和骨侵蝕，從而可早期診斷痛風。我們探討了超音波運用在早期診斷痛風於無症狀高尿酸血症患者之有效性。方法：這個橫斷性對照研究使用超音波來檢查六個關節，換言之，雙側第一蹠趾關節，踝關節和膝關節。我們評估了二種痛風特色性的超音波發現（雙輪廓癥及痛風石）以及幾種挑選的風險因素。我們選用卡方檢驗或非配對t檢驗進行差異性之比較。結果：我們登記了51例高尿酸血症患者（其中30例是無症狀高尿酸血症患者患者，21例是痛風患者），以及10例正常血中尿酸值之對照組。雙輪廓癥可見於90％的無症狀高尿酸血症患者和76.2％的痛風患者。痛風石可見於26.7％的無症狀高尿酸血症患者和33.3％的痛風患者。對照組沒有這些發現。結論：我們發現雙輪廓癥在無症狀高尿酸血症患者身上有高盛行率。超音波下發現雙輪廓癥之存在對於無症狀高尿酸血症患者有良好的診斷價值（高敏感性及高特異性）。

Objective: Gout and hyperuricemia are associated with damage to multiple organs, metabolic syndrome, cardiovascular disease, and chronic kidney disease. Current evidence is insufficient for developing recommendations regarding early diagnosis of gout and treatment in asymptomatic hyperuricemia (AH) patients. Musculoskeletal ultrasound can detect tophi deposition, cartilage abnormalities, joint effusion, and bony erosions and thus enable early diagnosis of gout. We investigated the effectiveness of ultrasound in early diagnosis of gout in patients with AH. Methods: In this cross-sectional, controlled study, ultrasound was used to examine six joints, i.e., the bilateral first metatarsophalangeal joints, ankles, and knees. Two characteristic ultrasound findings for gout—the double contour (DC) sign and tophi—and selected risk factors were evaluated. Differences were compared with the chi-square test or unpaired t test. Results: We enrolled 51 patients with hyperuricemia—30 with AH and 21 with gout—and 10 normouricemic controls. DC signs were seen in 90% of AH patients and 76.2% of gout patients. Tophi were seen in 26.7% of AH patients and 33.3% of gout patients. No such findings were present in controls. Conclusion: The prevalence of DC sign was high in AH patients. The presence of the DC sign on ultrasound had a good diagnostic value (high sensitivity and high specificity) for AH patients.