Clinical performance of Xpert MTB/RIF on contrast-enhanced ultrasound-guided core biopsy specimens for rapid diagnosis of superficial tuberculous lymphadenitis in high TB burden settings

Value of ultrasound‑guided puncture combined with GeneXpert MTB/RIF technology in the diagnosis of pleural tuberculosis

The aim of the present study was to analyze the pathological and laboratory findings of pleural lesions post ultrasound-guided biopsy and to assess the diagnostic utility of percutaneous ultrasound-guided puncture combined with GeneXpert Mycobacterium tuberculosis (MTB)/resistance to rifampin (RIF) in pleural tuberculosis (TB) diagnosis. A retrospective analysis was conducted on 46 patients who underwent ultrasound-guided biopsy at the Shandong Public Health Clinical Center (Shandong Chest Hospital) between April 2018 and April 2021. Of these, 27 patients were diagnosed with pleural TB, while 19 were confirmed to have non-pleural TB. Preoperative examinations were negative for all patients. Under ultrasound guidance, tissue samples were obtained through puncture for subsequent pathological and laboratory examination. All collected samples were subjected to acid fast staining, M. tuberculosis culture and GeneXpert MTB/RIF (Cepheid). The sensitivity, specificity and area under curve (AUC) value were compared across methods. Rifampicin drug susceptibility was detected using the proportional method and compared with results obtained from GeneXpert MTB/RIF. The sensitivity and specificity of acid-fast staining, M. tuberculosis culture and GeneXpert MTB/RIF in diagnosing pleural TB were 18.52 and 100.00%, 14.81 and 100.00, 96.30 and 94.74%, respectively. Consistency analysis demonstrated that the GeneXpert MTB/RIF technique exhibited good agreement (κ=0.91), whereas the agreement for acid fast staining (κ=0.16) and M. tuberculosis culture (κ=0.13) was poor. Data analysis was performed by combining the results of the three detection methods with pathological findings. The diagnostic value for pleural TB was highest for GeneXpert MTB/RIF technology combined with pathology (AUC value=0.97), followed by M. tuberculosis culture combined with pathology (AUC value=0.94) and acid-fast staining combined with pathology (AUC value=0.94). No surgical complications were observed. Of the 27 samples, 4 tested positive using the M. tuberculosis culture method. Rifampicin resistance was detected from the bacterial colonies through the proportional method, with results consistent with those obtained from the GeneXpert MTB/RIF method. Ultrasound-guided percutaneous biopsy is considered a safe and effective approach for diagnosing pleural TB, Its sensitivity is much higher than that of pleural effusion, Moreover, there is currently limited research on ultrasound-guided pleural biopsy combined with laboratory testing worldwide. Ultrasound-guided puncture combined with GeneXpert MTB/RIF technology is of significant value in the diagnosis of pleural TB and in determining rifampicin resistance.

Diagnostic performance analysis of Xpert MTB/RIF in lymph node tuberculosis: A retrospective study

AIMS

To retrospectively analyze the diagnostic efficacy of Xpert MTB/RIF (Xpert) in lymph node tuberculosis (LNTB).

METHODS

Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and area under the curve (AUC) of Xpert, pathological examination and culture for LNTB were calculated.

RESULTS

421 suspected LNTB cases were categorized into the LNTB group (377 cases) and non-LNTB group (44 cases). The sensitivities of Xpert, pathological examination, and culture were 72.15%, 20.69%, 30.24%, respectively, with NPVs of 29.53%, 12.83%, 14.33%. The AUC values were 0.861, 0.603, 0.651, respectively. The sensitivity of Xpert varied across sample types: tissue (64.73%), puncture fluid (74.42%), and pus (96.05%). For specific lymph node locations, the sensitivity was head-and-neck (72.51%), mediastinal (84.21%), and axillary (45.83%).

CONCLUSIONS

Xpert demonstrates high diagnostic value for LNTB, particularly in pus samples. It also performs better in mediastinal and head-and-neck lymph node samples compared to axillary lymph node samples.

Comparison of the Accuracy of Two Different Molecular Tests for the Diagnosis of Tuberculous Lymphadenitis Using Core Needle Biopsy Specimens: A Diagnostic Accuracy Study

Purpose

To evaluate the diagnostic accuracy of the CapitalBio Mycobacterium real-time polymerase chain reaction assay (CapitalBio test) testing of core needle biopsy (CNB) specimens for tuberculous lymphadenitis (TBL) and to compare it with Xpert MTB/RIF.

Methods

We retrospectively analyzed the medical data on patients with suspected peripheral TBL. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) of the CapitalBio test, Xpert MTB/RIF, and parallel test (positive result for either of these two tests) were calculated to evaluate their diagnostic efficacy compared with the final clinical diagnosis.

Results

The study included 114 patients. For diagnosing TBL using CNB samples, the sensitivity, specificity, PPV, NPV, and AUC were 65.0%, 100.0%, 100.0%, 28.6%, and 0.83, respectively, for the CapitalBio test; 72.0%, 100.0%, 100.0%, 33.3%, and 0.86, respectively, for Xpert MTB/RIF; and 82.0%, 100.0%, 100.0%, 43.8%, and 0.91, respectively, for the parallel test.

Conclusion

The accuracy of the CapitalBio test and Xpert MTB/RIF for diagnosing TBL using CNB specimens was moderate, while the sensitivity and NPV of these two tests were relatively low. The diagnostic accuracy of the CapitalBio test was slightly lower than that of Xpert MTB/RIF, but the difference between the two was not statistically significant. Parallel test might improve the diagnostic accuracy but not substantially over a single test.

Reassessing the Value of Contrast-Enhanced Ultrasonography in Differential Diagnosis of Cervical Tuberculous Lymphadenitis and Lymph Node Metastasis of Papillary Thyroid Carcinoma

AIM

We aimed to evaluate the ability of contrast-enhanced ultrasonography (CEUS) to perform differential diagnosis of cervical tuberculous lymphadenitis and lymph node metastasis from papillary thyroid cancer (PTC).

METHODS

We analyzed 102 enlarged cervical lymph nodes as diagnosed by conventional ultrasound (US) and CEUS. The US and CEUS enhancement pattern and the time intensity curve (TIC) of the metastatic lymph nodes or tuberculous lymph nodes were compared following standard pathological protocols. The TIC included peak time (TTP), peak intensity (PI), and area under the gamma curve (AUC).

RESULTS

Pathological results demonstrated that 48 out of the 102 enlarged lymph nodes were lymph node metastasis from PTC, while 54 were tuberculous lymphadenitis. There was statistically significant differences in hyperechoic islands, pulse-like enhancement, and asynchronous enhancement between tuberculous lymphadenitis and lymph node metastasis (P < 0.05), but their diagnostic sensitivity and specificity were unsatisfactory. In addition, our data did not show statistically significant difference in enhancement direction, enlarged range on CEUS, and perfusion defect (P > 0.05). Similarly, quantitative parameters such as PI, TTP, and AUC did not yield significant differences between the groups.

CONCLUSION

Taken together, the present results demonstrate that CEUS can provide valuable information on lymph node blood flow, which can be used to identify tuberculous lymphadenitis and lymph node metastasis of PTC.

Contrast-enhanced ultrasound guided pleural biopsy improves diagnostic confidence for pleural based lesions: a 3-year prospective study

Objective

To evaluate the accuracy and safety of contrast-enhanced ultrasound (CEUS) guided biopsy in the diagnosis of radiologically determined pleural based lesions.

Method

A prospective study was conducted on patients with radiologically determined pleural based lesions. Patients who met the inclusion criteria received pleural biopsy guided by CEUS to obtain specimens, followed by histomathological and microbiological examinations. After treatment and follow-up, surgical thoracoscopy was performed on cases with undefinite diagnosis.

Result

A total of 460 patients were finally included. CEUS showed internal necrosis in 72.17% cases and obvious peripheral vessels in 55.43% cases, both of which were significantly higher than the conventional ultrasound imaged (p < 0.05). The diagnostic accuracy through CEUS guided biopsy sampling was 98.91% (455/460). The microbiological diagnostic yield achieved 71.88% (225/313) in infectious lesions. In 330 cases combined pleural effusion, CEUS guided biopsy increased the diagnostic yield from 60.30% (199 /330) to 98.36% (325 /330) in all cases (p < 0.05), from 15.56% (14/90) to 94.44% (85/90) in malignant lesions (p < 0.01) and from 77.08% (185/240) to 100% (240/240) in infectious lesions (p < 0.05). No serious adverse events occurred.

Conclusion

CEUS guided biopsy provides a minimally invasive, effective and safe diagnostic biopsy method for pleural lesions.

Clinical Trials Registration: Chinese Clinical Trial Registry ChiCTR2000029749 (ChiCTR, www.chictr.org.cn).