From the Department of Orthopaedics, All India Institute of Medical Sciences, New Delhi, India.
Nepalgunj Medical College, Nepalgunj, Nepal.
Clin Nucl Med. 2021 Jun 1;46(6):449-455. doi: 10.1097/RLU.0000000000003518.
The aim of this study was to explore the utility of 18F-FDG PET/CT in the assessment of response to antitubercular treatment (ATT) and identification of treatment endpoint.
Forty patients (mean age, 35.3 years; 27 men) with clinically, radiologically, and histopathologically proven joint tuberculosis prospectively underwent clinical, biochemical, and PET/CT evaluation at baseline and after ~6, 12, and 18 months of ATT. Two patients were lost to follow-up, and 1 defaulted treatment. The remaining 37 were followed up until complete response (CR) was achieved. Images were visually and quantitatively (SUVmax ratio and metabolically active disease volume [MV]) evaluated by 2 experienced nuclear medicine physicians.
Knee (n = 18) and ankle (n = 7) were the most frequently involved sites. The median MV and SUVmax ratio at baseline were 85.10 mL and 7.21, respectively. Five patients had noncontiguous vertebral involvement, 12 had pulmonary lesions, 2 had abscesses, 6 had mediastinal, and 30 had local lymph nodal involvement. Complete response was seen in 1/39, 11/37, and 30/37 patients after 6, 12, and 18 months of ATT. Significant reductions in visual analog scale score, tenderness, joint swelling, SUVmax ratios, and MVs (Friedman test, P < 0.001) were seen after each follow-up. The median time-to-CR in skeletal lesions was significantly longer than extraskeletal lesions (591 vs 409 days; Wilcoxon signed-rank test, P < 0.001). Time-to-CR in joint lesions positively correlated with MV at first follow-up (Pearson = 0.452, P = 0.005) and negatively correlated with percentage change in MV (first follow-up from baseline) (Pearson = -0.620, P < 0.001). ROC analysis yielded a cutoff of ≤71% reduction in MV at first follow-up (80.8% sensitivity, 81.8% specificity) to predict extension of ATT beyond 12 months. Using ROC analysis at second follow-up, a cutoff of ≤12.67 mL (for CR) was derived and was validated in patients at the third follow-up, with an accuracy of 84.4%. Patients with CR in PET/CT maintained disease-free state during a mean follow-up of 271 days.
18F-FDG PET/CT is an excellent tool in estimating total disease burden, assessing response to ATT and identification of treatment endpoint in joint tuberculosis.
本研究旨在探讨 18F-FDG PET/CT 在评估抗结核治疗（ATT）反应和确定治疗终点方面的应用价值。
40 例经临床、影像学和组织病理学证实的关节结核患者前瞻性接受基线、ATT 后约 6、12 和 18 个月的临床、生化和 PET/CT 评估。2 例患者失访，1 例患者治疗失败。其余 37 例患者随访至完全缓解（CR）。由 2 名有经验的核医学医师进行视觉和定量评估（SUVmax 比值和代谢活跃疾病体积[MV]）。
膝关节（n=18）和踝关节（n=7）是最常受累的部位。基线时 MV 和 SUVmax 比值中位数分别为 85.10 mL 和 7.21。5 例患者存在非连续椎体受累，12 例患者有肺部病变，2 例有脓肿，6 例有纵隔病变，30 例有局部淋巴结病变。ATT 后 6、12 和 18 个月时，分别有 1/39、11/37 和 30/37 例患者达到 CR。视觉模拟评分、压痛、关节肿胀、SUVmax 比值和 MV 均有显著降低（Friedman 检验，P<0.001）。骨骼病变达到 CR 的中位时间明显长于非骨骼病变（591 天 vs 409 天；Wilcoxon 符号秩检验，P<0.001）。关节病变达到 CR 的时间与首次随访时 MV 呈正相关（Pearson=0.452，P=0.005），与 MV 的百分比变化（首次随访与基线相比）呈负相关（Pearson=-0.620，P<0.001）。ROC 分析得出，首次随访时 MV 减少率≤71%（80.8%的敏感性，81.8%的特异性）可预测 ATT 延长至 12 个月以上。第二次随访时，ROC 分析得出一个截断值为≤12.67 mL（用于 CR），并在第三次随访时对患者进行了验证，准确率为 84.4%。在 PET/CT 中达到 CR 的患者在平均 271 天的随访中保持无病状态。
18F-FDG PET/CT 是评估关节结核总疾病负担、评估 ATT 反应和确定治疗终点的优秀工具。
