Infection and Drug Resistance (Jan 2023)
Application of Mycobacterium tuberculosis RNA for the Rapid Diagnosis of Lymph Node Tuberculosis Using Different Specimens
Abstract
Guocan Yu,1 Ting Lin,2 Yuehui Yu,3 Peijun Chen,2 Menghan Chen,3 Ying Zhang,4,* Gaoyi Yang4,* 1Zhejiang Tuberculosis Diagnosis and Treatment Center, Affiliated Hangzhou Chest Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China; 2The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, People’s Republic of China; 3Division of Health Sciences, Hangzhou Normal University, Hangzhou, Zhejiang, People’s Republic of China; 4Department of Ultrasound, Affiliated Hangzhou Chest Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China*These authors contributed equally to this workCorrespondence: Ying Zhang; Gaoyi Yang, Department of Ultrasound, Affiliated Hangzhou Chest Hospital, Zhejiang University School of Medicine, No. 208 East Huancheng Road, Hangzhou, Zhejiang, People’s Republic of China, Email [email protected]; [email protected]: To evaluate the accuracy of Mycobacterium tuberculosis (MTB)-RNA in the rapid diagnosis of lymph node tuberculosis (LNTB). Moreover, the difference in the diagnostic accuracy of MTB-RNA using different specimens was determined.Methods: We included patients with suspected LNTB who met the inclusion criteria and retrospectively analyzed their clinical data. The sensitivity, specificity, positive-predictive value (PPV), negative-predictive value (NPV), and area under the curve (AUC) of MTB-RNA and culture were calculated and its diagnostic accuracy for LNTB was evaluated in comparison with the final clinical diagnosis.Results: Overall, 285 patients were included in the study. The overall sensitivity, specificity, PPV, NPV, and AUC of MTB-RNA were 40.6%, 100.0%, 100.0%, 17.0%, and 0.70, respectively. These values were 30.8%, 100.0%, 100.0%, 16.0%, and 0.65, respectively, for tissue specimens; 34.2%, 100.0%, 100.0%, 24.6%, and 0.67, respectively, for puncture specimens; and 57.14%, 100.0%, 100.0%, 5.3%, and 0.79, respectively, for pus specimens. These values of culture were 24.4%, 100.0%, 100.0%, 13.9%, and 0.62, respectively, for all specimens; 17.6%, 100.0%, 100.0%, 13.8%, and 0.59, respectively, for tissue specimens; 25.3%, 100.0%, 100.0%, 22.4%, and 0.63, respectively, for puncture specimens; and 31.0%, 100.0%, 100.0%, 3.3%, and 0.65, respectively, for pus specimens.Conclusion: The diagnostic efficacy of MTB-RNA for the rapid diagnosis of LNTB was moderate, but its sensitivity was low. The lymph node pus specimens were the most sensitive for MTB-RNA testing, followed by puncture specimens; tissues were the least sensitive. Pus specimens should be preferably obtained in case only this test is to be used for diagnosis.Keywords: LNTB, pus, puncture, tissue, sensitivity, diagnostic accuracy