全膝关节置换术后假体周围痛风发作临床上极为少见。由于痛风发作时的临床表现及实验室检查与假体周围急性感染极为相似, 故容易导致误诊。对于假体周围急性感染的患者, 为了及时控制感染并同时保留假体, 常常需要尽早进行关节清创灌洗术并长时间使用抗生素, 而术后关节制动也会导致膝关节功能受限。因此, 术前除外假体周围痛风发作等无菌性关节炎极为重要。本文报道1例长期患有糖尿病及口服激素所致全身免疫缺陷的患者因右膝骨性关节炎进行膝关节置换术, 术后8周时突发发热、关节肿痛及关节功能受限, 同时血白细胞、红细胞沉降率、C反应蛋白显著升高。根据现有的肌肉骨骼感染协会假体周围感染的诊断标准该患者误诊为假体周围急性感染, 并进行了保留假体的关节清理灌洗术。术后患者症状及实验室炎性指标仅有短期好转, 同时病原学结果显示为阴性。当关节清理术后11 d患者全身和局部症状再次出现时, 对该患者进行关节穿刺, 偏光显微镜下关节液晶体检测证实为急性痛风发作。使用抗痛风药物治疗后症状消失, 炎症指标恢复正常, 2年随访无复发。尽管假体周围通风发作十分罕见, 但其仍应作为全膝关节置换术后关节肿痛的一个鉴别诊断, 目前现有的假体周围感染的诊断标准中没有设立除外诊断标准, 提示晶体性关节炎的可能性未在全膝关节置换术后关节肿痛发生时获得重视, 极易带来误诊。因此, 术前常规进行关节液晶体检测非常必要。

Periprosthetic gout flare is a rare arthritic condition after total knee arthroplasty, but the symptoms of gout may have often been mistaken as acute periprosthetic infection given their similarity. Misdiagnosis as periprosthetic infection can lead to unnecessary surgery, long-term dependence on anti-biotics, and even malfunction of the involved knee joint. Here, we report a case study of a patient with immunodeficiency condition of long-term oral glucocorticoid and diabetes mellitus, who had undergone a knee replacement 8 weeks before. The initial symptoms of fever and joint pain together with the dysfunction of her right knee with elevated inflammatory markers, such as increased serum leukocytes, erythrocyte sedimentation rate, C-reactive protein, and synovial cell counts led to a diagnosis of acute periprosthetic infection. Arthrocentesis and bacterial culture were performed preoperatively. According to the current Musculoskeletal Infection Society (MSIS) criteria for diagnosis of periprosthetic infection, the case was classified as periprosthetic infection and a prosthesis retained debridement surgery was performed. However we got negative culture results in all the pre-operative and intro-operative samples. The symptoms as well as the laboratory inflammatory markers improved shortly after the debridement surgery until the 11th day when all the similar systemic and local symptoms recurred. With a remedial crystal analysis of synovial fluid from the patient, gouty flare was found to be the cause of acute arthritis finally. Accor-dingly, after anti-gout medications were administrated, the symptoms associated with acute arthritis gra- dually subsided, and there was no recurrence during a 24-month follow-up. This article described the cli-nical manifestation, diagnosis and differential diagnosis, treatment of a case of periprosthetic gout. Although relatively rare, gout should be considered as a differential diagnosis in suspected periprosthetic infection. Current criteria for periprosthetic infection can not exclude the diagnosis of periprosthetic gout flare, it is therefore imperative that the analysis of joint aspirate for crystals be conducted to determine the correct course of treatment, or unnecessary surgical procedure may be performed in periprosthetic gout case.