Development and Validation of a Scoring System for Differential Diagnosis of Tuberculosis and Metastatic Tumor in the Spine

Abstract

Shuang Cao,1,2,* Xin Gao,1,* Guangjian Bai,1,* Baoquan Xin,1,* Tao Wang,1 Jiashi Cao,1 Kai Lv,1 Chengzhang Zhu,1 Xiangzhi Ni,1 Weiwei Zou,3 Yejin Zhou,2 Jianru Xiao,1 Tielong Liu1 1Orthopedic Oncology Center, Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai, People’s Republic of China; 2Department of Orthopedics, Third Affiliated Hospital of Anhui Medical University, Hefei, Anhui Province, People’s Republic of China; 3Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai, People’s Republic of China*These authors contributed equally to this workCorrespondence: Tielong Liu; Jianru XiaoOrthopedic Oncology Center, Department of Orthopaedics, Changzheng Hospital, No. 415 Fengyang Road, Huangpu District, Shanghai, People’s Republic of ChinaTel [phone]Fax [phone]Email [email protected]; [email protected]: Spinal tuberculosis (TB) and metastatic tumor (MT) are common diseases with similar manifestations. Although pathological evaluation is the gold standard to confirm diagnosis, performing biopsies in all patients is not feasible. This study is aimed to create a scoring system to facilitate the differential diagnosis of spinal TB and MT before invasive procedures.Methods: Altogether, 447 patients with spinal TB (n=198) and MT (n=249) were retrospectively analyzed. Patients were randomly assigned at 2:1 ratio to a training cohort and a validation cohort. Clinical, laboratory, and radiological diagnostic factors were identified by χ2 and multiple logistic regression analyses. The scoring system was then established based on the identified independent diagnostic factors scored by regression coefficient β value, with the cut-off value being determined by ROC curve. The sensitivity and specificity of the system was calculated by comparing the predicted diagnosis with their actual pathological diagnosis.Results: This scoring system was composed of 5 items: pain worsens at night (0 or 2 points), CRP value (0 or 3 points), tumor marker values (0 or 2 points), skip lesions (0 or 3 points), and intervertebral space destruction (0 or 3 points). Patients scoring higher than 7.5 could be diagnosed as spinal TB, otherwise, MT. According to the internal validation, the sensitivity and specificity of the system were 87.9% and 91.6%, respectively.Conclusion: This study established and validated a scoring system which could be used to differentiate spinal TB from MT, thus helping clinicians in quick and accurate differential diagnosis.Keywords: scoring system, differential diagnosis, spine, tuberculosis, metastatic tumor

Keywords

• scoring system
• differential diagnosis
• spine
• tuberculosis
• metastatic tumor