Utility of Fine Needle Aspiration Cytology (FNAC) in the diagnosis of tuberculous lymphadenitis compared to GeneXpert in a tertiary health care center in Northern Odisha, India

Fine needle aspiration biopsy in low- and middle-income countries

Fine needle aspiration biopsy (FNAB) in low- and middle-income countries (LMIC), can provide minimally invasive, cost-effective tissue diagnosis with rapid assessment and specimen triage, which is advantageous in these resource-limited settings. Nevertheless, challenges such as equipment shortages, reagents, and lack of trained personnel exist. This article discusses the effectiveness of FNAB for diagnosis of malignant and inflammatory conditions across various organs, such as lymph nodes, breast, soft tissue, and thyroid and advocates for increased training opportunities and collaboration with academic centers to enhance diagnostic accuracy and access to pathology services.

Efficacy and tolerability of a 4-month ofloxacin-containing regimen compared to a 6-month regimen in the treatment of patients with superficial lymph node tuberculosis: a randomized trial

BACKGROUND

Tuberculosis (TB) lymphadenitis is the most common form of extra-pulmonary TB, and the treatment duration is six months. This non-inferiority based randomized clinical trial in South India evaluated the efficacy and safety of a four-month ofloxacin containing regimen in tuberculosis lymphadenitis (TBL) patients.

METHODS

New, adult, HIV-negative, microbiologically and or histopathologically confirmed superficial lymph node TB patients were randomized to either four-month oflaxacin containing test regimen [ofloxacin (O), isoniazid (H), rifampicin (R), pyrazinamide (Z) -2RHZO daily/ 2RHO thrice-weekly] or a six-month thrice-weekly control regimen (2HRZ, ethambutol/4RH). The treatment was directly observed. Clinical progress was monitored monthly during and up to 12 months post-treatment, and thereafter every three months up to 24 months. The primary outcome was determined by response at the end of treatment and TB recurrence during the 24 months post-treatment.

RESULTS

Of the 302 patients randomized, 298 (98.7%) were eligible for modified intention-to-treat (ITT) analysis and 294 (97%) for per-protocol (PP) analysis. The TB recurrence-free favourable response in the PP analysis was 94.0% (95% CI: 90.1-97.8) and 94.5% (95% CI: 90.8-98.2) in the test and control regimen respectively, while in the ITT analysis, it was 92.7% and 93.2%. The TB recurrence-free favourable response in the test regimen was non-inferior to the control regimen 0.5% (95% CI: -4.8-5.9) in the PP analysis based on the 6% non-inferiority margin. Treatment was modified for drug toxicity in two patients in the test regimen, while one patient had a paradoxical reaction.

CONCLUSION

The 4-month ofloxacin containing regimen was found to be non-inferior and as safe as the 6-month thrice-weekly control regimen.

Cytomorphological patterns and clinical features of presumptive tubercular lymphadenitis patients and their comparison with bacteriological detection methods: a cross-sectional study

INTRODUCTION

Tuberculous lymphadenitis (TBLN) is an infection of the lymph node caused by Mycobacterium tuberculosis. Histological diagnoses of presumptive patients are often accompanied by cytomorphological features. However, the sensitivities of these features are often precluded by the variable degrees of narrative similarities compared to other diagnostic modalities.

OBJECTIVE

The aim of this study was to investigate and compare the cytomorphological and clinical features of presumptive TBLN patients with bacteriological detection methods.

METHODS

A similar cohort of TBLN patients from our previous study who were enrolled prospectively from the ALERT Specialized Hospital, Addis Ababa, Ethiopia, was considered for this analysis. SPSS version 26 was used for data analysis. Descriptive analysis was conducted to characterize the study population using the independent variable and presented with frequency tables. The chi-square test was used to measure the association. A P-value of < 0.05 was considered statistically significant.

RESULTS

Using FNAC, 60/126 (47.6%) of the participants were reported to have features consistent with TB. Of the total FNAC-positive cases, many (30/60 and 27/60) showed pattern B (caseous necrosis only) and pattern C (epithelioid granuloma with caseous necrosis), respectively. Strong concordance was observed in Pattern A (abundant caseous necrosis with few epithelioid macrophages) followed by patterns B and C with GeneXpert and MGIT culture (P value < 0.001). Night sweats and alcohol intake were shown to correlate with positive cases as reported by FNAC (P value = 0.008 respectively), GeneXpert (P value = 0.02 & 0.001), and culture methods (P-value = < 0.001 & 0.002).

CONCLUSION

Cytomorphological features, particularly patterns A, B, and C, could be considered in the diagnosis of TBLN given their comparable outcomes with bacteriological detection methods. On another note, we recommend that due care and attention be given when treating TBLN patients based solely on clinical presentation, as these diagnostics may be prone to false results, leading to inappropriate administration of anti-TB drugs and other consequences.

Significance of Various Diagnostic Modalities in Detection of Tuberculosis in Cervical Lymphadenopathy: A Study of 200 Cases

BACKGROUND

Extrapulmonary tuberculosis (EPTB) makes for 25% of all instances of tuberculosis (TB) patients. The enigmatic clinical presentation of EPTB makes identification difficult since it simulates other chronic conditions such as neoplastic and inflammatory disorders and could culminate in treatment that is either insufficient or not required. For an affirmative and confirmed diagnosis, a substantial level of suspicion is imperative. The paucibacillary feature of EPTB makes diagnosis extremely difficult and necessitates the use of many diagnostic methods to arrive at a precise diagnosis. In December 2010, the World Health Organization recommended using GeneXpert/cartridge-based nucleic acid amplification test (CBNAAT) for the initial assessment of suspected cases of EPTB. Furthermore, fine-needle aspiration cytology (FNAC), Ziehl-Neelsen (ZN) stain, and the CBNAAT have to be utilized to exclude other possible origins of granulomatous inflammation. The goal of the current investigation is to comprehend how FNAC and ZN stains relate to CBNAAT and their diagnostic value.

METHODS

The evaluation included all suspected instances of tubercular lymphadenopathy, and adequate aspirates were obtained from the site of the enlarged cervical lymph nodes. Smears were made following FNAC and stained with ZN stain as well as hematoxylin and eosin stain. Simultaneously, CBNAAT and culture evaluations were conducted on the same aspirates. This cross-sectional study took place at a tertiary care center and encompassed 200 individuals with clinical manifestations of EPTB.

RESULTS

There were 200 cases of suspected tubercular lymphadenitis (TBLN). According to the FNAC results, TBLN was detected in 71 (47.6%) of these 200 cases, followed by necrotizing lymphadenitis in 56 (37.5%), chronic caseating granulomatous lymphadenitis in 47 (31.5%), and reactive lymphadenitis in 26 (17.4%). They were correlated with CBNAAT results, which showed that all instances of tuberculous lymphadenitis, 85.71% of cases of necrotizing lymphadenitis, 55.32% of cases of chronic caseating granulomatous lymphadenitis, and 2 (7.69%) cases of reactive lymphadenitis were CBNAAT positive.

CONCLUSION

CBNAAT should be utilized with FNAC and ZN staining to diagnose EPTB. The CBNAAT assay demonstrated a significant advantage in the identification of previously unidentified FNAC patients. Despite being a simple diagnostic tool, FNAC has a lower specificity and significantly lower precision than CBNAAT in correctly identifying cases of EPTB because it exhibits similar cytomorphological characteristics with lesions that are not associated with TB.

Utility of the Proposed Sydney System for Classification of Fine-Needle Aspiration Cytopathology of Lymph Node: A Retrospective Study at a Tertiary Care Center

INTRODUCTION

Fine-needle aspiration cytology (FNAC) is an established first-line technique for the evaluation of lymphadenopathy and, with the help of ancillary testing, can in many instances obviate the need for an open biopsy. The Sydney system was recently proposed to provide consensus guidelines for the performance, classification, and reporting of lymph node FNAC. The present study was undertaken to evaluate its utility and study the impact of rapid on-site evaluation (ROSE).

MATERIAL AND METHODS

A retrospective analysis in which 1,500 lymph node FNACs was reviewed and assigned a diagnostic category from the Sydney system. Cyto-histopathological correlation and adequacy parameters were evaluated.

OBSERVATION AND RESULTS

The cervical group of lymph nodes was the commonest group aspirated (89.7%). A total of 1,205/1,500 (80.3%) cases were category II (benign), and necrotizing granulomatous lymphadenitis was the most common pathology. The 750 cases with ROSE were subclassified as follows: 15 category I (inadequate), 629 category II (benign), 2 category III (atypia of undetermined significance), 9 category IV (suspicious for malignancy), and 95 category V (malignant). Among 750 cases without ROSE, 75 cases were in category I, 576 in category II, 3 in category III, 6 in category IV, and 90 in category V. Category I was thus significantly lower in the ROSE group compared to the non-ROSE group. Overall, the risk of malignancy was L1-0%, L2-0.20%, L3-100%, L4-92.3%, and L5-100%. Accuracy parameters revealed a sensitivity of 97.7%, specificity of 100%, PPV of 100%, NPV of 99.10%, and diagnostic accuracy of 99.54%.

DISCUSSION AND CONCLUSION

FNAC can be used as the 1st line of treatment for lymph node pathology. ROSE can be used as an add-on to FNAC for reducing unsatisfactory rates and help triage material for ancillary testing whenever possible. The Sydney system should be implemented for achieving uniformity and reproducibility.

Xpert MTB/RIF Assay for the Diagnosis of Lymph Node Tuberculosis in Children: A Systematic Review and Meta-Analysis

Background: Lymph node tuberculosis (LNTB) is the leading type of extrapulmonary tuberculosis (EPTB) causing death in children. The Xpert MTB/RIF assay is a novel rapid test for the diagnosis of LNTB. Although previous evidence suggests that Xpert is reliably accurate in diagnosing EPTB in children, information is lacking for the specific type of LNTB in children. The aim of this study was to systematically assess the accuracy and reliability of Xpert for the diagnosis of LNTB in children. Methods: We systematically searched four databases, Embase, Cochrane Library, PubMed, and Web of Science, which extracted relevant data according to predefined inclusion and exclusion criteria. The data were analyzed by meta-Disc 1.4 and Stata 12.0 software to determine sensitivity, specificity, diagnostic odds ratio (DOR), etc. Results: A total of 646 samples from 8 studies were included in the analysis. The pooled sensitivity, specificity, negative likelihood ratio (NLR), positive likelihood ratio (PLR,) and combined diagnostic odds ratio (DOR) of Xpert for all samples were 0.79 (95% CI 0.70, 0.87), 0.90 (95% CI 0.86, 0.92), 0.29 (95% CI 0.19, 0.43), 7.20 (95% CI 3.32, 15.60), and 37.56 (95% CI 13.04, 108.15), respectively. The area under the curve (AUC) of the summary receiver operating characteristic (sROC) curve was 0.9050. Conclusion: Overall, Xpert showed moderate sensitivity and high specificity compared with culture in the diagnosis of LNTB in children. In addition, after analyzing the combined diagnostic odds ratio and positive LR, our study showed that Xpert has excellent diagnostic accuracy.

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.

Integration of cytopathology with molecular tests to improve the lab diagnosis for TBLN suspected patients

Background

Tuberculosis lymphadenitis (TBLN) diagnosis is often challenging in most resource poor settings. Often cytopathologic diagnosis of TBLN suspected patients is inconclusive impeding timely clinical management of TBLN suspected patients, further exposing suspected patients either for unnecessary use of antibiotics or empirical treatment. This may lead to inappropriate treatment outcome or more suffering of suspected patients from the disease. In this study, an integrated diagnostic approach has been evaluated to elucidate its utility in the identification of TBLN suspected patients.

Methods

A cross-sectional study was conducted on 96 clinically diagnosed TBLN suspected patients, where fine needle aspirate (FNA) samples were collected at the time of diagnosis. FNA cytology, Ziehl-Neelsen (ZN), Auramine O (AO) staining, GeneXpert MTB/RIF and Real time PCR (RT-PCR) were performed on concentrated FNA samples. Considering culture as a gold standard, the sensitivity, specificity, positive and negative predictive values were calculated. Cohen’s Kappa value was used to measure interrater variability and level of agreement and a P-value of <0.05 was considered as statistically significant.

Result

Out of the 96 FNA sample, 12 (12.5%) were identified to have Mycobacterium tuberculosis (Mtb) using ZN staining, 27 (28.1%) using AO staining, 51 (53.2%) using FNAC, 43 (44.7%) using GeneXpert MTB/RIF, 51 (53.1%) using Real time PCR (RT-PCR) and 36 (37.5%) using Lowenstein-Jensen (LJ) culture. Compared to LJ culture, the sensitivities of GeneXpert MTB/RIF, RT-PCR, and FNAC were 91.7%, 97.2%, and 97.2%, respectively and the specificities were 83.3%, 73.3%, and 68.3%, respectively. GeneXpert MTB/RIF and RT-PCR when combined with FNAC detected 61 (63.5%) cases as having Mtb, and the sensitivity and specificity was 100% and 58.3%, respectively.

Conclusion

FNA cytology and RT-PCR detected more TBLN cases compared to other Mtb detection tools and the detection sensitivity even improved when FNA cytology was combined with GeneXpert MTB/RIF, performed on concentrated FNA sample, suggesting the combined tests as an alternative approach for improved diagnosis of TBLN.