痛風石與非痛風石關節炎之關節與肌腱病變：以超音波為工具之病例－－對照研究

Arthropathy and tendinopathy in patients with tophaceous and non-tophaceous gout: a case-controlled ultrasonographic study

目的：研究痛風石與非痛風石患者在超音波下的關節與肌腱病變之特性。方法：我們執行一個前瞻性、觀察型之病例－－對照研究，利用骨骼肌肉超音波來評估膝關節、踝關節、第一及第二趾掌骨關節，與下肢的肌腱與肌腱附著點。利用費雪精確性檢定或曼－－惠特尼U檢定法，來分析各種超音波發現的差異。結果：24個痛風石病人與36個非痛風石病人參與這個研究。痛風石患者之股骨髁雙輪廓徵象明顯較非痛風石患者為多（50% 與15.3%; p=0.001）。在第一及第二趾掌骨關節中，雙輪廓徵象、關節周圍之痛風石與骨侵蝕等發生率，痛風石患者皆明顯高於非痛風石患者。肌腱內痛風石，包括跟腱（43.8%與6.9%）、近端／遠端髕骨肌腱（29.2/41.7%與1.4/8.3%）、脛骨前肌／後肌肌腱（14.6/39.6%與0/1.4%）、腓骨長肌與短肌肌腱（29.2% 與0），在痛風石患者皆遠高於非痛風石患者（所有之p≤0.002）。肌腱附著點病變常見於所有痛風患者中：7.5%的近端與20%的遠端髕骨肌腱、與13.3%的跟腱，都發現這種異常，但病例組與對照組之間並沒有統計差異。結論：在超音波下，痛風石患者具有高度盛行之關節內與關節外病變，顯示體內尿酸沉積較非痛風石患者為多。這個證據支持我們針對這群患者，給予更積極與長期的降尿酸藥物治療。

Objective: To determine the characteristics of tendon and joint involvement in patients with tophaceous and non-tophaceous gout on ultrasonography (US). Method: We performed a prospective, observational, case-controlled study using US to evaluate the knee, ankle, 1st and 2nd metatarsal-phalangeal (MTP) joints, and the tendons and entheses of the lower limbs. Differences were analyzed by Fisher’s exact or Mann-Whitney U-tests. Results: Twenty-four patients with tophaceous gout and 36 subjects with nontophaceous gout were recruited. Double contour signs (DCS) of the femoral condyles were significantly more prevalent in the tophaceous gout group compared to the non-tophaceous group (50% vs. 15.3%; p=0.001). The 1st and 2nd MTP joints of patients with tophaceous gout had significantly more DCS, periarticular tophi, and bone erosions than patients with non-tophaceous gout (p≤0.002). Intratendinous tophi in the Achilles tendons (43.8% vs. 6.9%), proximal/distal patella tendons (29.2%/41.7% vs. 1.4%/8.3%), tibialis anterior/posterior tendons (14.6%/39.6% vs. 0/1.4%), and peroneus longus and brevis tendons (29.2% vs. 0) were significantly more frequent in patients with tophaceous gout than patients with non-tophaceous gout (p≤0.002). Enthesopathies were commonly observed; specifically 7.5% of proximal patella tendons, 20% of distal patella tendons, and 13.3% of Achilles tendons presented with enthesopathies. No statistical differences existed between groups. Conclusion: Patients with tophaceous gout had significantly more prevalent intra- and extra-articular pathology on US, suggesting a larger quantity of monosodium urate depositions, than patients with non-tophaceous gout. We thus recommend a more aggressive and longer duration of urate-lowering therapy in patients with tophaceous gout.