Diagnosis Of Tuberculous Lymphadenitis Research Articles

Clinicoepidemiologic considerations in the diagnosis of tuberculous lymphadenitis: evidence from a high burden country

ObjectivesTuberculosis is the biggest health issue worldwide, with tuberculous lymphadenitis (TBL) being its most common extrapulmonary manifestation. Clinical diagnoses of TBL often pose challenges; thus, this study aimed to analyze the clinical, epidemiologic, and laboratory aspects of TBL in Debre Markos Specialized Comprehensive Hospital, northwest Ethiopia. MethodsThe study was conducted at Debre Markos Specialized Comprehensive Hospital from October 2019 to March 2021. Patients with lymphadenitis displaying cytomorphologic features of tuberculosis were enrolled. A checklist was used to collect clinicodemographic data. ResultsAmong a total of 294 patients with TBL, 237 (80.61%) were adults aged 15-45 years. A fluctuant consistency (177; 60.20%; n = 294) with predominant involvement of cervical lymph nodes (229; 77.8%) was the most frequent presentation. Most patients did not have either HIV infection (235; 94.37%; n = 261) or known chronic medical illnesses (250; 95.8%). Constitutional symptoms (113; 41.85%; n = 270) and chronic cough (56; 20.74%; n = 270) were infrequent. The erythrocyte sedimentation rate (ESR) was increased in the majority of patients (133; 80%; n = 165), of whom extreme elevation (≥100 mm/hour) seen in 63 (38.18 %) patients and the mean ESR for our participants was 78.64 mm/hour. ConclusionTBL typically presents as a fluctuant neck mass, predominantly in young adults. The majority of patients have no constitutional symptoms or cough. HIV infection or chronic medical illnesses are uncommon. The raised erythrocyte sedimentation rate is a fairly consistent finding.

The value of histological examination in the diagnosis of tuberculous lymphadenitis in the era of rapid molecular diagnosis

Extrapulmonary tuberculosis often poses a diagnostic challenge. This study aimed to assess the value of histological examination in diagnosing tuberculous lymphadenitis (LNTB) when performed simultaneously with rapid molecular assay (Xpert MTB/RIF) testing. People presumed to have LNTB were prospectively enrolled in a tertiary care hospital. Excision biopsy was performed and tested by histology, Xpert, and culture. Of 390 lymph nodes, 11 (2.8%) were positive by AFB microscopy, 124 (31.8%) by Xpert, 137 (35.1%) by culture, and histopathology was consistent with TB in 208 (53.3%). Altogether, LNTB was diagnosed in 228 and bacteriologically confirmed TB in 178 cases. Against culture, histopathology versus Xpert had higher sensitivity (93 vs. 62%) but lower specificity (68 vs. 83%). In patients with short clinical history, a significantly higher number of Xpert-positive specimens were culture-positive. Among patients with histology suggestive of TB, no difference was seen in response to treatment between bacteriology positive and negative, but a significant slow response was noted in bacteriology confirmed TB with nonspecific histology. In a country like Pakistan, with high TB and low HIV prevalence, diagnosis is possible for more than 95% of LNTB when Xpert and histopathology examination is used in combination, compared to less than 60% by Xpert alone.

Diagnostic value of serum adenosine deaminase in tuberculous lymphadenitis

Background: Extra-pulmonary tuberculosis often requires FNAC or biopsy of lymph node to reach a final diagnosis of tuberculous lymphadenitis, which is invasive, expensive, and needs an advanced setting. Estimation of adenosine deaminase (ADA) in different body fluid and serum has been suggested as a quick, cheap, and reliable test for tuberculosis. Objective: The study was intended to assess the usefulness of serum ADA in the diagnosis of tuberculous lymphadenitis. Methods: This was a cross-sectional observational study, conducted in BSMMU over a two year period and included 68 participants, divided equally into two group e.g. tuberculous lymphadenitis and a healthy comparison group. As tuberculous lymphadenitis, only newly diagnosed cases, labeled on the basis of histopathological findings of epithelioid granuloma with caseation necrosis were included. Serum ADA concentrations were estimated by enzymatic method and compared between groups. Results: The mean serum ADA concentration was found to be 25.52±7.11 U/L in tuberculous lymphadenitis group, which was significantly higher (p=0.000) than that of the healthy comparison group (14.82±3.85 U/L). Three different cut-off values of serum ADA (18.25 U/L, 20.45 U/L, 22.15 U/L) were used to determine the best predictive value for the diagnosis of tuberculous lymphadenitis. Sensitivity and specificity of these cut off values were 91.2% and 82.4%, 79.4% and 88.2%, 67.6% and 97.1% respectively. Conclusion: It is clearly denoted by the study that, tuberculous lymphadenitis patients has significant higher serum ADA then the healthy comparison group. This result indicates that serum ADA can be used as a useful adjunct in the diagnosis of tuberculous lymphadenitis with conventional investigations. Bangladesh Med Res Counc Bull 2021; 47(2): 151-155

Combination method for the diagnosis of Tuberculous lymphadenitis in high burden settings

BackgroundIndia reports the highest number of extrapulmonary tuberculosis (EPTB) cases globally, most of which are lymph node TB (LNTB). In high tuberculosis (TB) burden countries rapid diagnosis is very important. Fine needle aspirate cytology (FNAC) diagnosis can be made with features of caseous necrosis with/without epithelioid granulomas. However, bacteriological confirmation is essential. This study was performed to evaluate the performance of the diagnostic tests available namely FNAC, GeneXpert (GX) and Ziehl Neelsen stain (ZN) stain at resource restricted settings, for LNTB.MethodsFNAC samples from affected lymph nodes were collected from 100 consenting patients with clinically suspected LNTB. FNA material was analyzed by cytomorphology, ZN and GX. If no Mycobacterium tuberculosis (MTB) was detected, repeat aspirate was cultured on Lowenstein Jensen medium. Descriptive statistical analysis was performed.ResultsOut of 100 cases, 73% showed cytological features consistent with TB. The most common cytomorphological pattern was epithelioid cell granulomas with caseous necrosis (59%). Caseous necrosis only pattern was seen in 14%. MTB was detected in 34% by ZN and 60% by GX. Overall, the combination of FNAC, ZN, GX detected 85% of LNTB.ConclusionsA combination of FNAC, ZN and GX is a practical tool that can improve and quicken the diagnosis of LNTB in resource restricted high-burden settings.

“Tuberculous and Nontuberculous Cervical Lymphadenitis: A Clinical Experience”

Introduction: Tuberculosis is one of the leading causes of death in adults. Tuberculous lymphadenitis continues to be a major health problem in our country. In patient with cervical lump, tuberculosis remains a common cause. Tuberculous cervical lymphadenitis is commonly encountered in clinical practice. Objective: To observe whether there are any differences in clinical characteristic between tuberculous and nontuberculous lymphadenitis and to evaluate the importance of fine needle aspiration cytology (FNAC) in the management of tuberculous cervical lymphadenitis. Materials & Methods: A prospective study was carried out among 101 patients of cervical lymphadenitis in ENT department of Mission General Hospital, Nilphamary, Bangladesh. The study period was from June 2019 to June 2019. Results: There were 53 male and 48 female. The age ranged from 9 to 68 years. Posterior triangles were found to be the most common involved site. The incidences of constitutional symptoms, like malaise, anorexia, weight loss and fever were similar between the two groups. Thirty nine patients were diagnosed as tuberculous lymphadenitis by FNAC, 53 patients diagnosed as reactive lymphadenitis and no definitive diagnosis were made for 8 patients. The excisional biopsy reported 42 patients as tuberculous lymphadenitis, 56 were diagnosed as reactive lymphadenitis and two patients were diagnosed as Non-Hodgkin’s Lymphoma. In this study sensitivity and specificity of FNAC in the diagnosis of the tuberculous lymphadenitis were 85.71% and 94.82% respectively. Conclusion: Patients with tuberculous and non-tuberculous lymphadenitis had similar clinical features and hence were difficult to differentiate clinically. FNAC is a highly specific tool in the diagnosis of tuberculous lymphadenitis.

TB Antigen-Stimulated CXCR3 Ligand Assay for Diagnosis of Tuberculous Lymphadenitis.

The diagnosis of tuberculous lymphadenitis (TB-LAP) is challenging. We evaluated the role of blood CXC chemokine receptor 3 (CXCR3) ligands in its diagnosis. A total of 65 lymphadenopathy patients were enrolled and lymph node sampling was performed. We also recruited 113 control subjects, consisting of 27 with positive results and 86 with negative results, in the interferon (IFN)-γ release assay (IGRA). In all study subjects, whole-blood samples were collected using the IGRA methodology. After incubation, plasma levels of IFN-γ and two CXCR3 ligands, IFN-inducible T-cell a chemoattractant (I-TAC) and monokine induced by IFN-γ (MIG), were measured using immunoassay. Fifty-three TB-LAP patients were enrolled. TB antigen-stimulated IFN-γ, I-TAC, and MIG levels were all significantly higher in the TB-LAP patients than in the controls and non-TB-LAP patients. The levels of I-TAC and MIG, but not IFN-γ, showed significant differences between the TB-LAP patients and IGRA-positive controls. Area under the receiver operating characteristic curves (AUROCs) of IFN-γ, I-TAC, and MIG were 0.955, 0.958, and 0.959, respectively, for differentiating TB-LAP from control group, and were 0.912, 0.956, and 0.936, respectively, for differentiating TB-LAP from non-TB-LAP. In conclusion, the TB antigen-stimulated MIG and I-TAC could be useful biomarkers in the diagnosis of TB-LAP.

Immunocytochemical Study of Rabbit-Polyclonal to Mycobacterium Tuberculosis, AB905: Improving Diagnostic of Tuberculous Lymphadenitis

Tuberculous lymphadenitis (TBLN) is the most common form of extrapulmonary tuberculosis. However, the optimal diagnosis using Fine-Needle Aspiration Cytology (FNAC) or excisional biopsy is uncertain. This research aims to improve the diagnostic of TBLN with FNAC and immunocytochemistry (ICC) compared to the response to antituberculosis therapy. The cross-sectional study involved 43 patients with the criteria for TBLN diagnosis based on the appropriate clinical history of tuberculosis and indicative cytological results. Immunocytochemical examination employed rabbit-polyclonal to Mycobacterium tuberculosis (MTB) antibody (AB905). The MTB expression was found in 35 out of 43 cases (81%) that appropriate cytological features of the tuberculosis process. Meanwhile, eight out of 43 cases (19%) did not express MTB. Diagnostic tests for lesions with a positive cytologic appearance of TBLN and ICC were compared to the response to anti-tuberculosis therapy, revealing the sensitivity, specificity, positive predictive value, and negative predictive value of 95.2%, 75%, 95.2%, and 17%, respectively. Besides, Fisher's exact tests utilized to identify the relationship between two variables; p 0.05 was considered significant. This research found immunocytochemical study was a sensitive and specific tool for improving the diagnostic of TBLN.

English

English

Fine-Needle Aspiration Cytology in Diagnosis of Tuberculous Lymphadenitis: Experience From a Tertiary Hospital in Tanzania

Abstract Objectives Tuberculous lymphadenitis is among the common causes of lymphadenopathy in low-resource countries. Data regarding diagnosis of tuberculous lymphadenitis based on fine-needle aspiration cytology of the lymph nodes are scant in our setting. The current study was conducted to determine the usefulness of fine-needle aspiration materials in the diagnosis of Tb lymphadenitis among patients who presented with enlarged lymph nodes. Methods A prospective study was conducted at Muhimbili National Hospital for the duration of 1 year (April 2016 to March 2017). Patients with enlarged lymph nodes were subjected to fine-needle aspiration cytology and smears were stained with Papanicolaou stain as well as Ziehl Nielsen (ZN). Criteria for diagnosing TB on cytology included granulomas, caseous necrosis, and epithelioid cells. All aspirates were subjected to GeneXpert assay for Mycobacterium tuberculosis. All cases diagnosed with TB based on cytological materials were initiated anti-TB. Follow-up of patients was done and response to treatment was used to confirm the diagnosis. Results One hundred sixteen cases were studied. Out of 116 cases of lymph nodes aspirated, 58 cases (50%) were diagnosed as tuberculous lymphadenitis. Females represented the majority of the cases, 31/58 (53%), and the most affected age group was 18 to 35 years. Cytomorphology of TB was found in 40/58 cases (68%) and ZN positivity for acid-fast bacilli (AFB) was found in 14/58 (24%) while Gene Xpert assay was positive in 29/58 (50%) of cases. The response to treatment was 100%. Conclusion Fine-needle aspiration cytology (FNAC) has shown to be simple, safe, and with higher accuracy in diagnosis of tuberculous lymphadenitis based on evaluation of cytomorphology with complementation of ZN stain for AFB in TB endemic areas. The diagnostic accuracy can be further increased by GeneXpert analysis, which can test the drug resistance of the Mycobacterium.

Diagnosis of mediastinal tuberculous lymphadenitis using endobronchial ultrasound-guided transbronchial needle aspiration with rinse fluid polymerase chain reaction

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has been gradually introduced in the diagnosis of mediastinal tuberculous (TB) lymphadenitis. The purposes of this study were to evaluate the utility of polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) using EBUS-TBNA rinse fluid and to explore the factors that influence the accuracy of EBUS-TBNA. A retrospective study with prospective data collection was carried out with patients with unselected mediastinal lymphadenopathy who underwent EBUS-TBNA and a TB-PCR study from April 2010 to July 2017. Patients without TB were excluded. The diagnostic accuracy rate for each diagnostic modality (pathology, smear, culture, and TB-PCR) was calculated respectively. The characteristics of the lymph node (LN) and the pathologic findings were analyzed as possible impact factors. 240 consecutive patients who received EBUS-TBNA were enrolled, and in the end, 21 patients with a diagnosis of TB lymphadenitis were included. When combined with histologic results and traditional microbiologic studies, the diagnostic accuracy of EBUS-TBNA was 57.1%. If TB-PCR was also utilized, the diagnostic accuracy would significantly increase to 71.4% (p<0.001). Univariate and multivariate regression analysis revealed that pathology showing necrosis had a higher positive microbiologic result when using EBUS-TBNA rinse fluid. EBUS-TBNA is a valuable tool for diagnosis of mediastinal TB lymphadenitis. Using TB-PCR assay and targeting LNs with a necrotic component would improve the diagnostic performance of EBUS-TBNA.

Diagnostic Accuracy of Fine Needle Aspiration Cytology in Diagnosis of Tuberculous Lymphadenitis

Background: Tuberculosis is still a global health problem. Most common presentation of extrapulmonary tuberculosis is tuberculous lymphadenitis. In our setting, keeping huge burden of tuberculosis in mind, clinicians have to depend on pathological diagnosis of enlarged lymph nodes, i.e., cytomorphology with acid-fast staining in diagnosing these cases so that diagnosis and management of such cases can be initiated quickly. Fine needle aspiration cytology (FNAC) of lymph nodes has been a simple, rapid and cost-effective procedure for diagnosis of various causes of lymphadenopathies.&#x0D; Objective: To determine the diagnostic accuracy of fine needle aspiration cytology in providing a diagnosis of tuberculous lymphadenitis patients in Bangladesh.&#x0D; Materials and Methods: This cross-sectional study was done on 317 subjects in Bangabandhu Sheikh Mujib Medical University (BSMMU) in collaboration with icddr,b. After clinical examination, fine needle aspiration (FNA) was done. The FNA materials were processed for Papanicoulaou staining (PAP stain), Ziehl-Neelsen staining and culture for the diagnosis of tuberculosis. Sensitivity, specificity, positive and negative predictive values of FNAC were determined where culture was taken as the gold standard.&#x0D; Results: Initially 351 clinically suspected tuberculous lymphadenitis patients were enrolled, but 34 cases were excluded due to diagnosis of malignancy. Among them 123 were male and 194 were female. Mean age was 27.91±13.16 years. Among the subjects 95.9% presented with cervical lymphadenopathy, others presented with lymphadenopathy of axillary or other groups of lymph nodes. The results of cytomorphological diagnosis of TB were in 58.36% cases, and culture was positive in 23.3% cases. Sensitivity, specificity, positive predictive value and negative predictive value of cytomorphological diagnosis were 79.7%, 48.1%, 31.9% and 88.6% respectively.&#x0D; Conclusions: FNAC is an effective diagnostic method for tuberculous lymphadenitis. It can diagnose granulomatous inflammation as well as reactive and other disease conditions including malignancies, thereby providing more information about the patient’s disease status.&#x0D; J Enam Med Col 2019; 9(1): 30-33

Efficacy of Fine-Needle Aspiration Cytology in the Diagnosis of Tuberculous Cervical Lymphadenitis

Objective: This study assesses the role of fine-needle aspiration cytology (FNAC) in the diagnosis of tuberculous lymphadenitis (TL) in comparison with histology and bacteriology findings. Study Design: We undertook a descriptive retrospective study of 937 FNAC specimens from 851 patients with cervical lymph nodes. The FNAC findings were then compared to histopathology and bacteriology. Results: Of the 937 aspirates, the cytopathological diagnoses consisted of 426 (55.9%) TL, 185 (24.3%) reactive lymphoid hyperplasia, 18 (2.3%) suppurative inflammation, 78 (10.2%) malignant metastatic tumor, and 54 (7%) lymphoma. Of the 426 TL cases, 171 were diagnosed by FNAC combined with bacteriological examination. In this group, 22 cases were found to be positive on Ziehl-Neelsen stain and 16 by culture. A histopathology report was available for 62 cases. Compared to histopathology, the overall diagnostic sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FNAC in the diagnosis of cervical TL were, respectively, 96.77, 100, 100, and 96.67%. When comparing bacteriology to histopathology, these values were 97.44, 100, 100, and 91.67%. Conclusion: Our study shows that FNAC is a sensitive and specific tool for the diagnosis of cervical TL.

Diagnostic accuracy of tuberculous lymphadenitis fine needle aspiration biopsy confirmed by PCR as gold standard

Indonesia is the second country with the TB (tuberculosis) burden in the world. Improvement in controlling TB and reducing the complications can accelerate early diagnosis and correct treatment. PCR test is a gold standard. However, it is quite expensive for routine diagnosis. Therefore, an accurate and cheaper diagnostic method such as fine needle aspiration biopsy is needed. The study aimsto determine the accuracy of fine needle aspiration biopsy cytology in the diagnosis of tuberculous lymphadenitis. A cross-sectional analytic study was conducted to the samples from patients suspected with tuberculous lymphadenitis. The fine needle aspiration biopsy (FNAB)test was performed and confirmed by PCR test.There is a comparison to the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of both methods. Sensitivity (92.50%), specificity (96.49%), accuracy (94.85%), positive predictive value (94.87%) and negative predictive value (94.83%) were in FNAB test compared to gold standard. We concluded that fine needle aspiration biopsy is a recommendation for a cheaper and accurate diagnostic test for tuberculous lymphadenitis diagnosis.

Diagnosis of Tuberculous Lymphadenitis from Fine Needle Aspirate by PCR

Lymph node involvement is the commonest form of extra pulmonary tuberculosis (EPTB). This study was undertaken to evaluate the role of PCR using IS6110 as a target for Mycobacterium tuberculosis complex in the diagnosis of tuberculous lymphadenitis (TB-L) and was done in Microbiology department of Sir Salimullah Medical College from July 2009 to June 2010. Fine needle aspiration was performed on 107 patients with a clinical suspicion of tuberculous lymphadenitis from different hospitals of Dhaka City Corporation area. All the aspirated samples were subjected to culture and PCR for M.tuberculosis. Out of 107 patients with lymphadenopathy most of the patients (85.9%) had cervical lymph node enlargement followed by axillary groups (12.1%) and inguinal groups (1.9%). Out of 107 cases, 65 (60.7%) were PCR positive and 56 (52.3%) were culture positive. Among 51 (47.7%) culture negative cases 9 (17.65) were PCR positive. Sensitivity of PCR was 100% and specificity was 82.4%.The positive predictive value (PPV), negative predictive value (NPV) and accuracy of PCR were 86.2%, 100% and 91.6% respectively. PCR is the most sensitive in the detection of M.tuberculosis in fine needle aspirate and could be useful technique in establishing the diagnosis of tuberculous lymphadenitis.

Concentration of fine needle aspirates similar to molecular method improves sensitivity of the diagnosis of tuberculous lymphadenitis in Addis Ababa, Ethiopia

BackgroundTuberculous lymphadenitis (TBLN) diagnosis has been a true challenge solely by clinical evidence in developing countries, due to limited the diagnostic facility on hand. However, the availability and affordability of available diagnostic tools in resource-limited settings like Ethiopia necessitates the quest for other techniques with added value over direct Z-N microscopy. Therefore, we aimed at to assess whether the concentration of lymph node aspirate similarly improves the detection rate of tuberculous lymphadenitis or not.Materials and methodsA cross-sectional study design was conducted on 132 individual subjects presumptive for tuberculous lymphadenitis from February to October 2013 in Addis Ababa, Ethiopia. Fine needle aspirate (FNA) samples were collected from the cases and cultured on Löwenstein-Jensen (LJ) slants. Identification of species and strains of mycobacteria was made by region of difference (RD) based polymerase chain reaction (PCR). Data entry and statistical analyses were performed by SPSS version 20. The confidence level of 95% was used for statistical significance.ResultA total of 132 study subjects were included in our study. Of these 56.1% (74/132) were positive for M. tuberculosis on culture. The detection rate of direct smear microscopy and the concentration method were 29.5 and 65.2% respectively. The sensitivity of direct smear microscopy was 43.2%, for concentrated smear microscopy 94.5%, for PCR 93.2% and for cytomorphology 95.4%. The level of agreement of concentrated ZN smear microscopy was 0.62 which was very similar with kappa of 0.58 of molecular (PCR) technique. AFB positivity by the concentration method and molecular method was increased in caseous aspirates as compared to purulent and hemorrhagic aspirates though it was not statistically significant (p-value = 0.18) and (p = 0.62) respectively.ConclusionThe concentration of FNA (Fine Needle Aspirate) aspirates for acid-fast smear microscopy similarly improves the sensitivity of acid fast bacilli in diagnosing of TBLN.

Separated Axillary Tuberculous Lymphadenitis: A Case Report

Tuberculosis (TB) still accounts for a high burden disease. It has been estimated that one third of the world population is infected with Mycobacterium tuberculosis, the most residing in developing countries. Separated axillary tuberculous lymphadenopathy is rare and described in patients without proof of previous or outstanding tuberculosis anywhere in the body. TB was supposed to be considered in the differential diagnosis of patients who present with axillary lymphadenopathy, especially in the endemic areas of Tuberculosis. Ultrasonography features of the axillary lymph node in our patient were not as helpful in diagnosis as the biopsy of the lymph node. Axillary tuberculous lymphadenitis diagnosis depends on the complete pathological examination. It remains both diagnostic and therapeutic challenge because it mimics other pathologic processes and yields inconsistent physical and laboratory findings. Diagnosis is difficult often requiring biopsy.

Tuberculous Lymphadenitis and Parotitis.

Tuberculous lymphadenitis is the most common extrapulmonary manifestation of disseminated tuberculosis (TB). It is considered to be the local manifestation of the systemic disease that has disseminated to local lymph nodes, but a high index of suspicion is needed for the diagnosis, because there are several infectious and noninfectious diseases that can mimic the same clinical picture. In recent years, different diagnostic methods have been introduced, including fine-needle aspiration cytology, which has emerged as a simple outpatient diagnostic procedure that replaced the complete excisional node biopsy, and a number of molecular methods which have greatly improved diagnostic accuracy. This chapter covers the most actual knowledge in terms of epidemiology, clinical manifestations, pathogenesis, and treatment and emphasizes current trends in diagnosis of tuberculous lymphadenitis. TB parotid gland involvement is extremely rare, even in countries in which TB is endemic. Because of the clinical similarity, parotid malignancy and other forms of parotid inflammatory disease always take priority over the rarely encountered TB parotitis when it comes to differential diagnosis. As a result, clinicians often fail to make a timely diagnosis of TB parotitis when facing a patient with a slowly growing parotid lump. This chapter highlights the most important features of this uncommon disease.

Endobronchial ultrasound-guided transbronchial needle aspiration rinse fluid polymerase chain reaction in the diagnosis of intrathoracic tuberculous lymphadenitis

Background: Intrathoracic tuberculous (TB) lymphadenitis is a diagnostic challenge to the clinician. Although endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) can obtain a sample from the affected lymph node, the diagnosis of TB lymphadenitis by cytopathology remains inaccurate.Objective: To evaluate the efficacy of EBUS-TBNA rinse fluid TB polymerase chain reaction (PCR) assay for the diagnosis of intrathoracic TB lymphadenitis.Methods: A retrospective study was conducted on 102 patients who underwent EBUS-TBNA for diagnostic evaluation of intrathoracic lymphadenopathy. EBUS-TBNA specimens were evaluated by cytopathological examination. Rinse fluid of the needle was routinely submitted for acid-fast bacillus (AFB) staining, mycobacterial culture, and TB-PCR using the AnyplexTM MTB/NTM real-time detection kit.Results: Of 102 patients, 16 were diagnosed with intrathoracic TB lymphadenitis by either microbiology, cytopathology, or on clinical grounds. The sensitivity, specificity, positive predictive value, and negative predictive value of rinse fluid TB PCR assay were 56.2%, 100.0%, 100.0%, and 92.5%, respectively. Using the area under the ROC curve (AUC) as a measure of a diagnostic performance, TB-PCR had the highest AUC, compared with mycobacterial culture, AFB smear, and finding of necrotizing granulomatous inflammation (0.78, 0.75, 0.56, and 0.72, respectively). A combination of TB PCR, mycobacterial culture, and finding of necrotizing granulomatous inflammation provided the best diagnostic performance (sensitivity, specificity, positive predictive value, negative predictive value, and AUC of 75.0%, 100.0%, 100.0%, 95.6%, and 0.88, respectively).Conclusions: EBUS-TBNA rinse fluid TB-PCR is useful in the diagnosis of intrathoracic TB lymphadenitis. Combining TB-PCR with mycobacterial culture and cytopathological findings improved the diagnosis performance.

Fine needle aspiration cytology in the diagnosis of Tuberculous lymphadenitis and utility of Ziehl Neelsen stain benefits and pitfalls

Introduction: In a developing country like India, tuberculous lymphadenitis is one of the most common presentations at OPDs. However, anti-tubercular treatment cannot be administered only on clinical suspicion. Cytomorphology with acid fast staining proves to be a valuable tool in diagnosing these cases along with culture. The study was undertaken to study the utility, limitations of fine needle aspiration cytology and various cytomorphological presentations in reference to Ziehl-Neelsen staining in tuberculous lymphadenitis and correlate the culture findings. Methods: The study was conducted for duration of two years with total of 170 cases at a tertiary care centre. The patients with clinically suspected lymphadenopathy were selected. Results: The incidence of tuberculous lymphadenitis was 68.8%. Overall AFB positivity was 64.1 %. Epithelioid cell granulomas with lymphocytes were the most common cytological picture and cases showing necrosis had highest AFB positivity. Maximum patients presented in second to fourth decade of life. Cervical region was the most common site of involvement with solitary lymphadenopathy as the most common presentation in contrast to matted lymph nodes as reported by others. Conclusion: Yet again Fine needle aspiration cytology is a safe, cheap and reliable procedure requiring minimal instrumentation and is highly sensitive to diagnose tuberculous lymphadenitis. The diagnostic index can be further increased by complementing cytomorphology with acid fast staining and culture techniques. However FNAC complimented with techniques like ELISA and PCR would give better dimensions to the current scenario of diagnosis and treatment modalities.

GeneXpert MTB/RIF Assay for the Diagnosis of Tuberculous Lymphadenitis on Concentrated Fine Needle Aspirates in High Tuberculosis Burden Settings.

IntroductionThe diagnosis of tuberculous lymphadenitis (TBL) remains challenging. The routinely used methods (cytology and smear microscopy) have sub-optimal sensitivity. Recently, WHO recommends GeneXpert to be used as the initial diagnostic test in patients suspected of having extra-pulmonary tuberculosis (EPTB). However, this was a conditional recommendation due to very low-quality evidence available and more studies are needed. In this study we evaluated the performance of Xpert for the diagnosis of TBL on concentrated fine needle aspirates (FNA) in Southwest Ethiopia.MethodsFNA was collected from presumptive TBL cases. Two smears were prepared from each aspirate and processed for cytology and conventional microscopy. The remaining aspirate was treated with N-acetyl-L-cysteine-NaOH and centrifuged for 15minutes at 3000g. The concentrated sediment was used for culture and Xpert test. Capilia TB-Neo test was used to differentiate M. tuberculosis complex (MTBC) from non-tuberculous mycobacteria (NTM). Composite bacteriological methods (culture and/or smear microscopy) were considered as a reference standard.ResultOut of 143 enrolled suspects, 64.3% (92/143) were confirmed TBL cases by the composite reference standard (CRS). Xpert detected M. tuberculosis complex (MTBC) in 60.1% (86/143) of the presumptive TBL cases. The sensitivity of Xpert compared to CRS was 87.8% [95% CI: 81.0–94.5] and specificity 91.1% [95% CI: 82.8–99.4]. The sensitivity was 27.8% for smear microscopy and 80% for cytology compared to CRS. Cytology showed the lowest specificity (57.8%). Xpert was positive in 4 out of 45 culture- and smear-negative cases. Among 47 cytomorphologically non-TBL cases, 15 were positive on Xpert. More than half of Xpert-positive cases were in the range of very low cut-off threshold values (28<Ct<38). Resistance to rifampicin was identified in 4.7% (4/86) of Xpert-positive cases.ConclusionXpert test showed a high sensitivity and specificity for the diagnosis of TBL on concentrated FNA samples. In addition, Xpert offered rapid detection of rifampicin-resistant M. tuberculosis strains from lymph node aspirates.