Fine needle aspiration cytology of suspected tuberculous lymphadenitis

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.

Impact of fine needle aspiration cytology strategy implemented at the microscopy center level for diagnosis of tuberculous lymphadenitis

INTRODUCTION

In India, EPTB accounts for about 50% of TB cases especially in people living with HIV/AIDS. Microbiological confirmation is present in only about 15% of EPTB cases. Tuberculous Lymphadenitis is the most common form of EPTB in India, accounting for around 35% of EPTB cases. Fine needle aspiration cytology has been found to be highly sensitive and specific in the diagnosis of tuberculous lymphadenitis with 83-94% accuracy. The procedure of AFB detection is exactly the same for the FNAC obtained smears as for the presently examined sputum smears at the DMCs. The aim of the present study was to determine the feasibility and effectiveness of FNAC strategy implemented at DMC level for detection of tuberculous lymphadenitis cases.

METHODS

The present study was a randomized cluster trial with one control and one intervention arm. At the intervention units (DMCs) all suspected tuberculous lymphadenitis cases was subjected to FNAC of the suspected superficial lymph nodes by the trained Medical Officers. The control group was free from any such intervention. Effectiveness and feasibility of FNAC strategy in the intervention group was determined by relevant indicators.

RESULTS

At the seven intervention DMCs, FNAC was performed on a total number of 1298 suspected cases of Tuberculous Lymphadenitis. Among them 294 cases were selected in the intervention arm and 196 cases in the control arm. Intervals between advice of FNAC and performance of FNAC as well as start of therapy was significantly low in the intervention arm. Complication was insignificant. The concordance between FNAC reports generated at the DMCs and that at Medical College estimated by agreement measurement kappa (0.970) suggested a high level of agreement.

CONCLUSION

Implementation of FNAC strategy at the DMC level for detection of tuberculous lymphadenitis cases was found to be feasible as well as effective.

Utility of Rapid On-Site Evaluation during Bronchoscopy in the Diagnosis of Pulmonary Tuberculosis

INTRODUCTION

The diagnostic value of rapid on-site evaluation (ROSE) in bronchoscopy for lung tumors has been widely researched. However, the diagnostic efficacy of ROSE for pulmonary tuberculosis (TB) has not been extensively assessed yet. This study aimed to examine the value of ROSE in diagnosing pulmonary TB during bronchoscopy, and the relationship between ROSE cytology patterns and acid-fast bacilli (AFB) smears and mycobacterial cultures.

METHODS

A retrospective study was conducted at a single respiratory endoscopy center, including 418 patients under clinical or radiological suspicion of having pulmonary TB who underwent bronchoscopy. In addition to the use of ROSE and definitive cytology, material obtained by aspiration/lavage or brushing was sent for AFB smear and mycobacterial culture. If histopathological examination was required, endobronchial biopsy, transbronchial lung biopsy, and transbronchial needle aspiration were performed at the discretion of the clinician. A composite reference standard (CRS) was used as the diagnostic gold standard for this study. The diagnosis obtained by ROSE was compared with the final diagnosis.

RESULTS

Of the 418 patients studied, 282 (67.5%) were diagnosed on the basis of bronchoscopic findings, as follows: pulmonary TB, in 238 (84.4%); non-TB, in 44 (15.6%). In 238 pulmonary TB patients, ROSE cytology showed granulomas without necrosis were observed in 107 cases, granulomas and necrosis in 51 cases, caseous necrosis only in 25 cases, and nonspecific inflammation in 55 cases. For the diagnosis of TB according to CRS, ROSE showed the sensitivity, specificity, positive predictive value, and negative predictive value were 76.9%, 68.2%, 92.9%, and 35.3%, respectively. The positivity rate for bacterial detection through acid-fast staining and culture during bronchoscopy was 51.7%. The cytological pattern showed a higher detection rate for bacteria in cases of necrosis.

DISCUSSION

The application of ROSE during bronchoscopy is a straightforward procedure that delivers an immediate and precise assessment regarding the adequacy of collected samples, enabling a preliminary diagnosis of pulmonary TB. ROSE has exhibited a higher sensitivity in detecting pulmonary TB compared to microbiological examinations. In addition, the cytological presentation of ROSE tends to show a higher positivity rate for microbiological testing in caseous necrosis. Therefore, samples with these characteristics should be prioritized for microbiological examination after on-site evaluation.

T, Manikandan A, Ravichandar S. Petals of rose: Application of rapid on-site evaluation in bronchoscopy

In present day scenario, procedures that are minimally invasive like FNAs and Core needle biopsies are on the rise. Rapid on-site evaluation (ROSE) is a laboratory service that assesses the cytomorphologic features from FNA smears or biopsy contact imprints in the biopsy room and can provide on the spot input and suggestions for the clinician through immediate cytological examination of the biopsy sample. ROSE also allows for a preliminary diagnosis, allowing for the requirement of additional material for ancillary studies. We are presenting two cases which highlights the merits of ROSE in cytological diagnosis.   In the first case, a thirty four year old male patient came with complaints of productive cough, breathlessness and fever. Bronchoscopic needle aspiration and biopsy was done with Rapid Onsite Evaluation. ROSE revealed two non-caseating epithelioid granulomas on the 4th pass. Bronchoscopic lymph node biopsy was non- contributory. With other clinical and biochemical parameters, diagnosis of Sarcoidosis was made. This case study underscores the significance of ROSE in arriving at the diagnosis.   In the other case, a fifty seven year old male patient came to hospital with productive cough and breathlessness (MMRC grade II). CT chest revealed features suggestive of bronchogenic carcinoma. ROSE was performed along with bronchial brush cytology in which presence of atypical cells with increased nuclear cytoplasmic ratio, nuclear hyperchromatism and nuclear molding was noted. On histopathological examination, it was diagnosed as a case of non-small cell carcinoma of lung – poorly differentiated type. This case proves the advantage of ROSE in avoiding repeated invasive procedures for the patient.

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

Background

India 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.

Methods

FNAC 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.

Results

Out 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.

Conclusions

A 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.

Elucidating the Etiologies of 18F-fluorodeoxyglucose-Avid Mediastinal Lymph Nodes Among Cancer Patients in a Tuberculosis-Endemic Region Using Endobronchial Ultrasound

Background

Non-malignant conditions, including infections (such as tuberculosis [TB]), can mimic malignancy with regards to their uptake of 18F-fluorodeoxyglucose (¹⁸F-FDG) tracer utilized for positron emission tomography-computed tomography (PET-CT) scan, as part of the diagnostic and staging workup of cancer patients. This poses a diagnostic challenge, for which tissue sampling is decisive. In this study, we aimed to determine the underlying etiologies of ¹⁸F-FDG-avid mediastinal lymph nodes among cancer patients in a TB-endemic demographic using endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and the respective sensitivity and specificity of PET-CT and EBUS in diagnosing malignancy.

Methodology

In this retrospective cross-sectional study, we analyzed the data of all cancer patients with ¹⁸F-FDG-avid mediastinal lymphadenopathy on diagnostic PET imaging, who later underwent EBUS-TBNA between July 2013 and December 2018 at our center. Logistic regression analysis was used to determine the relative risk of lymph node characteristics with malignant TBNA cytology, based on which a risk stratification model was formulated.

Results

A total of 178 patients were included in this study, comprising predominantly males (60.7%). The primary malignancy was lung cancer in 33 (18.5%) patients, while 145 (81.5%) had non-lung cancer. A total of 214 ¹⁸F-FDG lymph nodes were sampled, out of which TBNA revealed malignant cytology in only 44 (20.6%). The final diagnosis was malignancy, TB, and sarcoidosis in 42 (23.6%), 16 (9%), and 12 (6.7%) patients, respectively. Among the remaining, 98 (55%) patients were determined to have only reactive lymphadenopathy, of which 24 (24.5%) had nodal anthracosis, while TBNA was inadequate for the diagnosis in 10 (5.6%) patients. An increased risk of malignancy was associated with the size of lymph node [odds ratio (OR): 1.58 (confidence interval (CI): 1.19, 2.11; p = 0.001], the standard uptake value (SUV) of the lymph node on PET-CT [OR: 1.30 (CI: 1.15, 1.45); p = 0.001], and with primary lung malignancy [OR: 4.44 (CI: 1.96, 10.06); p = 0.001]. At an SUV cut-off value of 6.0, PET-CT had the sensitivity, specificity, positive predictive value, and negative predictive value of 73%, 70%, 49.3%, and 91.8%, respectively, for diagnosing malignancy, while the same for EBUS was estimated to be 93.3%, 100%, 100%, and 97%, respectively.

Conclusions

In addition to TB, benign etiologies including nodal anthracosis and sarcoidosis predominate as causes of ¹⁸F-FDG-avid mediastinal lymphadenopathy in cancer patients of a TB-endemic demographic. The predictable risk of malignancy on PET imaging increases with nodal size, SUV, and lung primary malignancy; however, EBUS clearly demonstrates a higher sensitivity.

Diagnostic yield of endoscopic ultrasound-guided fine-needle aspiration of tubercular lymphadenitis using combination of cytology and Gene Xpert Mycobacterium tuberculosis/rifampicin (MTB/RIF) genes

Diagnostic yield of an automated molecular test, Gene Xpert Mycobacterium tuberculosis/rifampicin (MTB/RIF), was evaluated in this study to simultaneously detect the MTB gene and resistance to rifampicin (RIF) on cytology samples acquired via endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNAC) in suspected tubercular lymphadenitis. Microscopy, cytology, Gene Xpert MTB/RIF assay data on Acid-fast bacillus (AFB), and traditional culture of lymph nodes were retrospectively analyzed. Thirty-one patients (median age 33.5 years, inter-quartile range [IQR] 21-66, 18, 58% female) presented with fever (28, 90%), dysphagia (2, 7%), and recurrent subacute intestinal obstruction (1, 3%). Gene Xpert showed higher sensitivity (30, 97%) compared to the other tests: cytology (23, 77%; odds ratio [OR] 8.8, 95% confidence interval [CI] 1.0-76.9; p = 0.05), AFB smears (12, 39%; OR 50, 95% CI 5.9-420.4; p = 0.00001), and conventional culture (4, 13%; OR 188.5, 95% CI 19.7-1796.3; p = 0.0000). We conclude that Gene Xpert MTB/RIF test on EUS-guided FNAC samples is very useful to diagnose tubercular lymphadenitis.

The Clinicopathological Features of Mediastinal Tuberculous Lymphadenitis in Cancer Patients and the Diagnostic Role of Endobronchial Ultrasound

Introduction

Mediastinal lymphadenopathy in cancer patients can be of both malignant and non-malignant (including infectious) etiology. Tuberculosis (TB) is an important differential in this regard, particularly in regions with high TB endemicity.

Objectives

To determine the incidence and clinical characteristics of mediastinal tuberculous lymphadenitis (MTBLA) in cancer patients of a TB-endemic region, and the diagnostic role of endobronchial ultrasound (EBUS) guided transbronchial needle aspiration (TBNA) in such patients, utilizing both cytopathological and microbiological parameters for diagnosing TB.

Materials and methods

We retrospectively analyzed the relevant clinical data of all cancer patients diagnosed with MTBLA after undergoing EBUS-TBNA at our center, between July 2013 till July 2018 (total five years). The diagnostic yield, sensitivity and specificity of cytopathological and microbiological investigations (including TB culture and Mycobacterium tuberculosis Gene Xpert assay) for diagnosis of MTBLA were determined.

Results

Of the total 493 cancer patients, MTBLA was diagnosed in 54 (11%), with mean age of 48 ± 12 years, and predominantly male gender (59.3%). Thirty-three (61.1%) patients were clinically asymptomatic at the time of presentation, while cough was reported by 13 (24.7%) patients and weight loss, shortness of breath and fever by only six (11.1%), six (11.1%) and five (9.2%) patients, respectively. Total 53% had an underlying gastrointestinal malignancy. Chest imaging revealed bilateral versus unilateral hilar lymph node enlargement in 32 (59.3%) against 22 (40.7%) patients, respectively, while only 14 (25.9%) had accompanying lung parenchymal findings. Granulomatous TBNA cytology was detected in 41 (77.3%) patients, giving a diagnostic yield of 70.3% for MTBLA, with an estimated sensitivity and specificity of 79.2% and 99%, respectively. TB culture and Gene Xpert had a respective sensitivity of 48% and 53%, with the combined diagnostic yield of 64.8%. Treatment response was achieved in 51 (94%) patients, based on which EBUS was estimated to have sensitivity and specificity of 89% and 99% respectively, with no reported complications.

Conclusion

Mediastinal TB can have diverse manifestations among cancer patients and can often be clinically occult, with overlapping radiological impressions. EBUS-TBNA can serve as a safe and reliable diagnostic tool in this regard.

Role of contrast-enhanced ultrasound guidance in core-needle biopsy for diagnosis of cervical tuberculous lymphadenitis

OBJECTIVE

To investigate the diagnostic value of core-needle biopsy (CNB) guided by contrast-enhanced ultrasound (CEUS) in cervical tuberculous lymphadenitis (CTL).

METHODS

178 patients with pathological confirmation of CTL were retrospectively enrolled. All of them had undergone CNB prior to the final surgery. According to the different ways of puncture guidance, they were divided into two groups: conventional ultrasound (US) group (n = 81) and CEUS group (n = 97). The comparison of diagnostic efficacy between two groups was compared and analyzed.

RESULTS

Among the 178 patients, 146 were directly diagnosed as CTL by CNB, including 59 patients in CEUS group and 87 patients in US group. The diagnostic accuracy were 89.7% (87/97) and 72.8% (59/81), respectively (P < 0.01). For subgroup analyses, differences among diagnostic efficacy ascribed to the different guiding methods were significant in medium size group (>2.0 cm and ≤3.0 cm) and large size group (>3.0 cm), 91.7% for CEUS group vs. 69.0% for US group (P < 0.05) and 84.4% for CEUS group vs. 57.7% for US group (P < 0.05), respectively.

CONCLUSIONS

In the diagnosis of CTL, compared with the US-guided CNB, CEUS-guided CNB have certain advantages, especially for larger lymph nodes.

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

OBJECTIVE

The diagnosis of superficial tuberculous lymphadenitis (TBLN) remains difficult due to low detection rate of etiology. To increase the diagnostic value for TBLN, contrast-enhanced ultrasound (CEUS) guided core biopsy was introduced to obtain the specimen followed by Xpert MTB/RIF (Xpert) and other methods testing and to explore the optimum diagnostic pattern for TBLN in China.

METHODS

A prospective study was performed on patients with suspected superficial TBLN. All patients underwent CEUS-guided core biopsy from which specimens were tested by histopathology, Xpert, acid-fast bacilli (AFB), and MGIT960 culture (MGIT960), respectively. The diagnostic values were calculated and compared.

RESULTS

A total of 328 patients were included the study, 272 were diagnosed as TBLN (254 definite TB, 18 probable TB) and 56 cases with Non-TBLN, and 100% (272/272) of TBLN patients obtained diagnosis sampled by CEUS-guided core biopsy. The overall sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of comprehensive diagnosis on the specimens by CEUS-guided core biopsy for TBLN were 100% ( 272/272, 95% CI 98.26-100.00), 94.64% (53/56, 95% CI 84.20-98.61), 98.91% (272/275, 95% CI 96.58-99.72), and 100% (53/53, 95% CI 91.58-100%), respectively. Xpert obtained 93.31% (237/254) of etiology detection rate on the specimens sampling by CEUS-guided biopsy. The etiology detection rate was associated with histopathological caseous necrosis.

CONCLUSIONS

Current examinations on specimens by CEUS-guided core biopsy can achieve a high diagnostic efficacy for TBLN. Pathological differentiation of CEUS-guided biopsy tissue, then followed by Xpert, may be the best pattern for the diagnosis of TBLN in high TB burden areas.

Nasopharyngeal Carcinoma: A Retrospective Study on Imaging Patterns at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia

Background

Nasopharyngeal carcinoma is one of the rare forms of cancer globally which has a high incidence in select geographic and ethnic populations. The current study aims to assess the clinical presentation, imaging patterns and radiology-pathology correlation of nasopharyngeal carcinoma.

Methods

This is a retrospective analysis of 80 patients with newly diagnosed nasopharyngeal carcinoma who came to Tikur Anbessa Specialized Hospital from January 2016 to August 2017. The patients' history, physical examination, abdominopelvic ultrasound, chest x-ray, computed tomography scan and biopsy reports were reviewed from their medical record. Patients who had previous history of treatment for nasopharyngeal carcinoma, those who did not have biopsy and those without imaging were excluded from the study.

Results

This study showed that 61(81.3%) patients had neck swelling as the initial clinical symptom, and the average time of presentation of symptoms was 6(IQR 8) months. On the other hand, 56(70.0%) were diagnosed with non-keratinizing undifferentiated nasopharyngeal carcinoma while 15(3.8%) had keratinizing nasopharyngeal carcinoma. Sixty-nine (86.3%) patients had nodal metastasis; 22.5% had invasion into the paranasal sinuses; 47.5% had T4 with T1, T2 and T3 being 18.8%, 17.5% and 7.5% stage respectively at time of diagnosis. Ninety percent of the cases had a diagnosis of nasopharyngeal carcinoma on imaging, but 10% were given alternative diagnosis.

Conclusion

Non-keratinizing undifferentiated type was the commonest histologic subtype in this study which is also recognized as the commonest one in endemic countries. A significant number did not have a specific histologic WHO type on pathology report which could in turn affect the management and assessment of risk factors.

Coexisting Somatostatin Receptor Expressing Gastric Neuroendocrine Tumor Primary and Lymph Nodal Tuberculosis on 68Ga-DOTANOC Positron Emission Tomography/Computed Tomography

Gastric neuroendocrine tumors (G-NETs) express somatostatin receptors (SSTR), which can be imaged using radiolabeled somatostatin analogs, including ⁶⁸Ga-DOTA octreotide analogs. SSTR expression is also seen in activated lymphocytes and macrophages, which might result in false-positive results on SSTR imaging, in patients with coexistent granulomatous pathologies including tuberculosis, sarcoidosis, and Wegener's granulomatosis. We present a case where ⁶⁸Ga-DOTANOC positron emission tomography/computed tomography (PET/CT) showed primary G-NET, with SSTR expressing nonregional lymph nodes which on histopathology showed necrotizing granulomas with Langhans histiocytes. Antitubercular therapy was started, and a decrease in size and SSTR expression in involved lymph nodes was noted on follow-up ⁶⁸Ga-DOTANOC PET/CT.

EBUS-TBNA in the rapid microbiological diagnosis of drug-resistant mediastinal tuberculous lymphadenopathy

This study aimed to examine the use of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the rapid diagnosis of mediastinal tuberculous lymphadenitis and drug-resistant mediastinal tuberculous lymphadenitis. A diagnosis of TB was confirmed by a positive Xpert MTB/RIF test or Mycobacterium tuberculosis culture. Rifampicin-resistant TB (RR-TB) or multidrug-resistant TB (MDR-TB) was diagnosed upon the detection of rifampicin resistance by Xpert MTB/RIF or resistance to rifampicin and isoniazid by phenotypic drug susceptibility testing (DST). Xpert MTB/RIF was positive in 43 of 56 patients (77%) and TB culture was positive in 31 of 56 patients (55%). Of these 56 patients, 25 (45%) were Xpert MTB/RIF positive and TB culture negative, 13 (23%) were Xpert MTB/RIF negative and TB culture positive, and 18 (32%) were Xpert MTB/RIF positive and TB culture positive. 11 patients (20%) had drug-resistant TB: seven with RR/MDR-TB, one with pre-extensively drug-resistant (XDR) TB, two with XDR-TB and one with isoniazid mono-resistance. An Xpert MTB/RIF assay carried out on EBUS-TBNA specimens provides rapid diagnosis of TB. Xpert MTB/RIF testing appears to have additional and more rapid sensitivity compared with culture alone. Culture-based DST provides an additional exclusive yield and the full resistance profile in addition to or instead of rifampicin resistance.

Diagnostic accuracy of Xpert MTB/RIF assay and non-molecular methods for the diagnosis of tuberculosis lymphadenitis

Background

Tuberculous lymphadenitis (TBLN) diagnosis remains a challenge in resource limited countries like Ethiopia. Most diagnostic centers in Ethiopia use smear microscopy, but it has low sensitivity in detecting tubercle bacilli in fine needle aspiration (FNA) specimens. FNA cytology (FNAC) is another widely applicable diagnostic option but it has low specificity for diagnosing TBLN. In 2014, WHO recommended Xpert MTB/RIF assay to be used in detecting TB from FNA specimen by considering the diagnostic limitations of microscopy and cytology. In Ethiopia, there is limited data on Xpert MTB/RIF performance in detecting TBLN from FNA. Therefore, this study aimed to evaluate the diagnostic performance of Xpert MTB/RIF assay and non-molecular methods (cytology, microscopy and culture) for the diagnosis of TBLN.

Methods

A cross-sectional study was conducted on 152 presumptive TBLN patients at St. Paul’s Hospital Millennium Medical College (SPHMMC) from December 2015 to May 2016 in Addis Ababa, Ethiopia. FNA specimens were collected from each patient. Individual patient specimens were examined by microscopy (acid fast and auramine O staining), cytology, Xpert MTB/RIF and culture. Each specimen was directly inoculated and its sediment following decontamination procedure onto two duplicate Löwenstein-Jensen (LJ) media. Composite culture (specimen positive by direct or concentrated or both culturing methods) and composite method (positive by either one of the non-molecular methods) were taken as reference methods. The data was captured and analyzed using software packages SPSS version 20 (SPSS Inc, Chicago, Illinois, USA). Sensitivity, specificity, positive predictive value, and negative predictive value were calculated.

Result

A total of 152 presumptive TBLN patients were enrolled in this study. Of these, 105(69%), 68(44.7%), 64(42%), 48(32%) and 33(22%) were positive for M. tuberculosis using composite method (positive by either one of the non-molecular method), composite culture, direct, and concentrated culture, respectively. TB positivity rate was 67.8%, 49.3%, 24.3%, and 14.5% using cytology, Xpert MTB/RIF, Auramine O (FM) microscopy, and Ziehl Nelson (ZN) microscopy, respectively. Using composite culture as reference, the sensitivity and specificity of Xpert MTB/RIF was 78% (95% CI: 73.7% to 82.3%) and 74% (95%CI: 69.4% to 78.6%), respectively. However, the sensitivity of Xpert MTB/RF improved from 78% to 92% using composite method as a reference. The high positivity rate observed in purulent (70%) followed by caseous (66.7%) type of aspirates by Xpert MTB/RIF.

Conclusion

Xpert MTB/RIF assay has both considerable sensitivity and specificity; it may be employed for better diagnosis, management and treatment of presumptive TBLN patients.

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

BACKGROUND/PURPOSE

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Epidemiology of tuberculous lymphadenitis in Africa: A systematic review and meta-analysis

INTRODUCTION

Tuberculous lymphadenitis is the most frequent form of extra-pulmonary TB (EPTB) and accounts for a considerable proportion of all EPTB cases. We conducted a systematic review of articles that described the epidemiological features of TBLN in Africa.

METHODS

Any article that characterized TBLN cases with respect to demographic, exposure and clinical features were included. Article search was restricted to African countries and those published in English language irrespective of publication year. The articles were retrieved from the electronic database of PubMed, Scopus, Cochrane library and Lens.org. Random effect pooled prevalence with 95% CI was computed based on Dersimonian and Laird method. To stabilize the variance, Freeman-Tukey double arcsine root transformation was done. The data were analyzed using Stata 14.

RESULTS

Of the total 833 articles retrieved, twenty-eight articles from 12 African countries fulfilled the eligibility criteria. A total of 6746 TBLN cases were identified. The majority of the cases, 4762 (70.6%) were from Ethiopia. Over 77% and 88% of identified TBLN were cervical in type and naïve to TB drugs. Among the total number of TBLN cases, 53% were female, 68% were in the age range of 15-44 years, 52% had a history of livestock exposure, 46% had a history of consuming raw milk/meat and 24% had history of BCG vaccination. The proportion of TBLN/HIV co-infection was much lower in Ethiopia (21%) than in other African countries (73%) and the overall African estimate (52%). Fever was recorded in 45%, night sweating in 55%, weight loss in 62% and cough for longer than two weeks in 32% of the TBLN cases.

CONCLUSIONS

TBLN was more common in females than in males. The high prevalence of TBLN in Ethiopia did not show directional correlation with HIV. Population based prospective studies are warranted to better define the risk factors of TBLN in Africa.

Light-emitting diode fluorescent microscopy and Xpert MTB/RIF® assay for diagnosis of pulmonary tuberculosis among patients attending Ambo hospital, west-central Ethiopia

Background

The relatively simple and cheaper light-emitting diode fluorescent microscopy (LED-FM) was recommended by the World Health Organization (WHO) to replace the conventional tuberculosis (TB) microscopy in both high- and low-volume laboratories. More recently the WHO also endorsed one more technique, Xpert MTB/RIF® assay (Xpert), for improved TB diagnosis particularly among human immunodeficiency virus (HIV)-infected cases. However, the relative performance of both of these tools differs from setting to setting in reference to the conventional TB diagnostics. This study thus aimed to evaluate these tools for TB detection in individuals visiting Ambo Hospital, west-central Ethiopia.

Methods

Cross-sectional early-morning sputum samples were collected from presumptive TB patients between January and August 2015. Socio-demographic data were captured using a structured questionnaire. Clinical information was gathered from patients’ medical records. The sputum samples were diagnosed using LED-FM, Xpert, concentrated Ziehl-Neelsen (cZN) staining and Lowenstein-Jensen (LJ) culture as the gold standard. Drug sensitivity test (DST) was also conducted.

Results

Out of 362 sputum samples collected and processed, 36(9.9%) were positive by LED-FM, 42(11.6%) by cZN and 50(13.8%) by Xpert. But, only 340 samples could be declared culture positive or negative for mycobacteria. Of these 340, eight were non-tubercle mycobacteria (NTM). Out of the remaining 332 samples, 45(13.6%) had culture-confirmed TB with 11(24.4%) being HIV co-infected. LED-FM, Xpert and culture detected 54.5% (6/11), 90.9% (10/11) and 100% (11/11) mycobacteria in HIV-positive individuals and 81.3% (26/32), 73.7% (28/38), 78.8% (26/33) and 73.2% (30/41), in HIV negatives respectively. Two samples were rifampicin resistant by both Xpert and DST. The overall sensitivity, specificity, positive and negative predictive values of LED-FM and Xpert were 77.8, 100, 100 and 96; and 93.3, 98, 97.5 and 98.9% respectively.

Conclusion

The data demonstrated the high diagnostic yield of Xpert. LED-FM sensitivity is higher compared to results quoted by recent systematic reviews although it appears to be lower than what was cited in the WHO policy statement (83.6%) during the recommendation of the technology. The high specificity of LED-FM in the study area is encouraging and is expected to boost its reliability and uptake.

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.

Diagnosis and treatment of paediatric tuberculosis: An insight review

Tuberculosis (TB) is a major public health problem, invading all age groups world-wide. It is an opportunistic infection affecting the individuals alone or with co-infections. Childhood TB is a neglected aspect and a significant health problem in epidemic areas. It constitutes more than 20% of TB incidence. Pediatric TB exists in the shadow of adult TB. The clinicians concentrate on pulmonary manifestation of TB, whereas it is a major problem in both pulmonary and extra-pulmonary infections. The rate of infection with this disease is mostly associated with poverty, social disruption and human immunodeficiency virus (HIV) infection. The diagnosis of extra-pulmonary TB (EPTB) is more difficult than pulmonary TB (PTB). Delayed diagnosis and executive treatment contribute to increase in the mortality rate in endemic areas. This article provides the evidence-based simple and safe screening method, indicating rapid, highly sensitive and specific diagnostic tests for pulmonary and EPTB in children. The most important aspect of treatment is the correct course of anti-tubercular drugs. This review serves the purpose of quick reference for microbiologists, epidemiologists, academicians, students and researchers. It provides guidance regarding early diagnosis and treatment accuracy of pediatric TB.

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

BACKGROUND

Tuberculous 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 METHODS

A 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.

RESULT

A 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.

CONCLUSION

The concentration of FNA (Fine Needle Aspirate) aspirates for acid-fast smear microscopy similarly improves the sensitivity of acid fast bacilli in diagnosing of TBLN.

Cytomorphological patterns of tubercular lymphadenitis and its comparison with Ziehl-Neelsen staining and culture in eastern up. (Gorakhpur region): Cytological study of 400 cases

Background:

Tuberculous lymphadenitis is most common cause of lymphadenopathy in developing countries. Although enormous literature is available on various aspects of the disease including cytological patterns and its incidence in others parts of India and in other countries, only limited literature is available regarding its incidence and morphological spectrum on cytology in eastern parts of Uttar Pradesh in Gorakhpur region.

Aim:

The present study was undertaken to estimate the incidence of tuberculous lymphadenitis in our settings along with its morphological spectrum on cytology as well as to determine the utility of culture of fine needle aspirates in addition to cytology and Ziehl–Neelsen (ZN) staining.

Material and Methods:

Four hundred cases of superficial lymphadenopathy were subjected to fine needle aspiration cytology (FNAC), and in case, smears were stained with Hematoxylin and eosin (H and E), Giemsa, and ZN stain and categorized into three cytomorphological patterns. All the aspirates were inoculated on two sterile Lowenstein Jensen (LJ) medium.

Result:

Out of 400 cases of consecutive lymph nodes aspirated, 180 cases (45%) showed features of tuberculous lymphadenitis. Smears revealed epithelioid granulomas with caseous necrosis in maximum cases (40%). On statistical analysis, difference between group I and group II was found to be significant (P < 0.05); while comparison between groups II and III as well as between groups I and III was found to be statistically insignificant. Overall, acid fast bacilli positivity was seen in 51.6% of the cases.

Conclusion:

FNAC has been proved very safe, highly sensitive, and first line investigation in diagnosing tubercular lymphadenitis. The sensitivity can be further be increased by complementary cytomorphology with acid fast staining. Diagnostic accuracy can further be increased by culture.

Tuberculous lymphadenitis: Comparison of cytomorphology, Ziehl-Neelsen staining, and rapid mycobacterial culture at a pediatric superspecialty hospital

Background:

To evaluate and compare the role of Ziehl–Neelsen (ZN) staining and mycobacterial culture in diagnosis of tuberculous lymphadenitis.

Materials and Methods:

A total of 56 fine needle aspirations (FNAs) from patients who were clinically suspected to have tuberculous lymphadenitis were included. Acid-fast Bacilli detection was attempted by ZN staining on smears as well as culture on Middlebrook 7H9 broth. Percentage positivity of both smears and culture was calculated.

Results:

Of the 56 cases, 46 showed cytomorphological features consistent with tuberculosis (TB). The most common pattern was only necrosis in 37 cases followed by necrotizing granulomas in 13 cases. ZN-stained smears were positive in 40 cases while culture was positive in only 27 cases. The highest smear and culture positivity was noted in cases with only necrosis. In six cases, diagnosis of TB was made on culture alone since smear was negative in these cases.

Conclusion:

FNA is a reliable technique for early and accurate diagnosis of tuberculous lymphadenitis in many cases. Mycobacterial culture by newer rapid techniques can assist in bacillary detection in smear-negative cases and also allows for drug sensitivity testing. Hence, culture should be resorted to in such cases.

Etiological study of lymphadenopathy in HIV-infected patients in a tertiary care hospital

INTRODUCTION

Human immunodeficiency virus (HIV) infection has become a global pandemic. Persistent generalized lymphadenopathy (PGL) is very common manifestation of HIV infection. Moreover, different opportunistic infections such as tuberculosis (TB) and malignancies may present with lymphadenopathy. Mycobacterium avium complex (MAC) infection is most common with cluster of differentiation (CD)4+ count ≤50 cells/μL. Fine-needle aspiration cytology (FNAC) offers a simple and effective modality for obtaining a representative sample of the material from lymph nodes, permitting cytological evaluation and other investigations.

AIMS AND OBJECTIVES

The aim of this study is to find out the different etiologies of lymphadenopathy in HIV-infected patients and to establish a possible correlation with CD4+ count.

MATERIALS AND METHODS

A total of 100 HIV-infected patients having significant (>1 cm) extrainguinal lymphadenopathy were studied in 1 year at the Department of Pathology by FNAC and the stains used were Leishman-Giemsa, Ziehl-Neelsen (ZN), Papanicoloau, and Gram stains. For tubercular culture, Löwenstein-Jensen (LJ) medium was used. CD4+count was done by flow cytometer.

RESULT

The present study revealed four types of cytomorphological variants in lymphadenopathy cases by FNAC, which include: Reactive hyperplasia and caseation necrosis; caseation necrosis and ill-formed granuloma; well-formed granuloma without any necrosis; and non-Hodgkin lymphoma (NHL). The highest acid-fast bacilli (AFB) positivity was among the patients showing caseation necrosis. Tubercular culture in LJ media turned out as a more sensitive method for diagnosis than routine ZN staining. The 2 cases that showed well-formed epithelioid granuloma without any necrosis turned out to be histoplasmosis and cryptococcosis, respectively. In this study, we found 2 cases of NHL. The study also revealed that caseation necrosis and AFB positivity along with opportunistic infections increases with decreased CD4+ count.

Isolated Retropancreatic Tuberculous Lymphadenitis Mimicking Carcinoma: A Diagnostic Challenge

Tuberculosis as a cause of obstructive jaundice is a rare entity with only a few cases reported in the literature. Patients with this condition usually present with a protracted illness, jaundice, and weight loss, which may be confused with malignancies. We are reporting unusual case of isolated enlarged tuberculous lymph node compressing the common bile duct in the retropancreatic region and causing obstructive jaundice in an immunocompetent patient which to the best of our knowledge is the first case of isolated retropancreatic tuberculous lymphadenitis in Saudi Arabia.

Tuberculous lymphadenopathy: Experience from the referral center of Northern India

Background:

Lymphadenopathy is the common form of extrapulmonary tuberculosis (TB) in the developing country like India. The aim of the study was to assess the clinical and the pathological features of tuberculous peripheral lymphadenopathy along with the effect of the antitubercular drugs on its clinical course.

Materials and Methods:

A prospective study was carried out in the department of pulmonary medicine from July 2013 to June 2014. Clinico-demographical and pathological characteristics of the patients of tuberculous lymphadenopathy were studied.

Results:

Two and four cases, 84 (41.2%) male and 120 (58.8%) females were diagnosed as the cases of tuberculous lymphadenopathy. Mean age of the patients were 28.45 ± 12.83. Palpable mass (100%) was the most common presenting feature. Cervical lymphadenopathy (92.6%) was the most common presentation of peripheral tuberculous lymphadenopathy. Most common cytological pattern seen was epithelioid granuloma with caseous necrosis (32.84%) followed by epithelioid granuloma without caseous necrosis on fine needle aspiration cytology (FNAC). Directly observed treatment short course (DOTS) for TB was effective in treating tuberculous lymphadenopathy.

Conclusion:

Tuberculous lymphadenopathy affects female more often than males. FNAC is the effective mean in diagnosing tuberculous lymphadenopathy. DOTS is the effective mean for treating tuberculous lymphadenopathy.

[Role of endobronchial ultrasound-guided transbronchial needle aspiration in the diagnosis of mediastinal tuberculosis]

INTRODUCTION

Mediastinal tuberculosis (TB) is rare and a diagnostic challenge. Transbronchial needle aspiration guided by endoscopic ultrasonography (EBUS-TBNA) is an essential tool for staging and diagnosing patients with lung cancer but to date there are no studies in our environment evaluating its efficacy in mediastinal TB.

METHODS

Patients with a final diagnosis of isolated intrathoracic tuberculous lymphadenitis over a 6-year period were included. We analyzed the cases on whom EBUS-TBNA was performed.

RESULTS

Forty-six patients with mediastinal lymphadenopathy without pulmonary involvement were identified and 29 underwent EBUS-TBNA. In 28 of 29 patients (96.6%) EBUS-TBNA was diagnostic and cytological findings confirmed granulomas in 93% of cases. Microbiological investigation revealed positive TB culture in 14 (48.2%) and positive PCR for Mycobacterium tuberculosis in 30% of cases on whom it was carried out. Eighty-four per cent of the patients were immigrants and when compared with the native population we found statistical differences in immune status and culture yield.

CONCLUSION

EBUS-TBNA is a safe and effective technique in the diagnosis of patients with suspected mediastinal TB.

Diagnostic performance of interferon-γ release assay for lymph node tuberculosis

The aim of the study was to evaluate the performance of interferon-γ (IFN-γ) release assay (IGRA) (T-SPOT.TB) for patients with suspected lymph node tuberculosis (TB). Of the 405 patients with suspected lymph node TB, enrolled from Beijing Chest Hospital between July 2011 and April 2015, 83 (20.5%) were microbiologically/histopathologically confirmed lymph node TB, and 282 (69.6%) did not have active TB. The remaining 21 inconclusive TB and 19 clinical TB were excluded from the final analysis (9.9%). T-SPOT.TB using peripheral blood mononuclear cells was performed to examine the IFN-γ response to the Mycobacterium tuberculosis-specific antigens early secretory antigenic target 6 and culture filtrate protein 10. The overall sensitivity and specificity for T-SPOT.TB were 90.4% and 70.5%, respectively. Spot-forming cells in the lymph node TB group (184 [48-596/10(6) peripheral blood mononuclear cells {PBMCs}]) were significantly higher than that in the nonactive TB group (0 [0-41]/10(6) PBMCs) (P<0.001). These results suggest that the IGRA assay could be a useful aid in the diagnosis of lymph node TB.

Efficacy of TB-PCR using EBUS-TBNA samples in patients with intrathoracic granulomatous lymphadenopathy

BACKGROUND

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is widely used to perform mediastinal lymph node sampling. However, little information is available on polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) using EBUS-TBNA samples in patients with intrathoracic granulomatous lymphadenopathy (IGL).

METHODS

A retrospective study using a prospectively collected database was performed from January 2010 to December 2014 to evaluate the efficacy of the TB-PCR test using EBUS-TBNA samples in patients with IGL. During the study period, 87 consecutive patients with isolated intrathoracic lymphadenopathy who received EBUS-TBNA were registered and 46 patients with IGL were included.

RESULTS

Of the 46 patients with IGL, tuberculous lymphadenitis and sarcoidosis were diagnosed in 16 and 30 patients, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of TB-PCR for tuberculous lymphadenitis were 56, 100, 100, and 81%, respectively. The overall diagnostic accuracy of TB-PCR for tuberculous lymphadenitis was 85%. In addition, seven (17%) patients had non-diagnostic results from a histological examination and all of them had non-diagnostic microbiological results of an acid-fast bacilli smear and culture. Four (57%) of the seven patients with non-diagnostic results had positive TB-PCR results, and anti-tuberculosis treatment led to clinical and radiological improvement in all of the patients.

CONCLUSIONS

TB-PCR using EBUS-TBNA samples is a useful laboratory test for diagnosing IGL. Moreover, this technique can prevent further invasive evaluation in patients whose histological and microbiological tests are non-diagnostic.

Correlation of cytomorphological patterns and acid-fast Bacilli positivity in tuberculous lymphadenitis in a rural population of southern India

Background:

One of the most common causes of lymphadenopathy in India is tuberculosis. It can be diagnosed by a minimally invasive procedure known as fine-needle aspiration cytology (FNAC), and thereby unnecessary surgical interventions are avoided.

Aim:

This study was undertaken to evaluate cytomorphological patterns of tuberculous lymphadenitis including human immunodeficiency virus-positive cases, to correlate the acid-fast Bacilli (AFB) positivity with cytomorphological patterns and also to find out overall AFB positivity.

Materials and Methods:

In this study, a total of 212 cases of cytologically proven tuberculous lymphadenitis were retrieved and analyzed retrospectively between March 2012 and March 2015 for three different cytomorphological patterns (epithelioid granuloma without necrosis [pattern A], epithelioid granuloma with necrosis [pattern B], and necrosis without epithelioid granuloma [pattern C]) and bacillary loads on Ziehl-Neelsen stain (ZN) for AFB.

Results:

Pattern A through C was observed in 40 (18.9%), 102 (48.1%), and 70 (33%) cases, respectively. AFB positivity was found in 2 (5%) cases of pattern A, 62 (60.8%) cases of pattern B, and 54 (77.1%) cases of pattern C. The highest percentage of AFB positivity (64.7%) was observed in aspirate containing purulent/pus and caseous/cheesy material. The overall AFB positivity was seen in 55.7% (118/212) cases. On grading of AFB positivity, Grade 1+ was observed in 29.7%, Grade 2+ was observed in 28.8%, and Grade 3+ was observed in 41.5% cases.

Conclusion:

FNAC is a sensitive, simple, convenient, safe, minimally invasive procedure to diagnose tuberculous lymphadenitis. Study of both cytomorphological patterns and ZN staining for AFB can improve the diagnostic yield. Regardless of the presence of granuloma, ZN stain must be employed whenever infective pathology is suspected.

The efficacy of the interferon-γ release assay for diagnosing cervical tuberculous lymphadenitis: A prospective controlled study

OBJECTIVES/HYPOTHESIS

The whole-blood interferon (IFN)-γ release assay (IGRA) has been studied mainly for diagnosing latent tuberculosis (TB). We prospectively evaluated its diagnostic usefulness in patients with suspected cervical TB lymphadenitis.

STUDY DESIGN

Prospective cohort study.

METHODS

An IGRA was performed in subjects with suspected TB lymphadenitis. To evaluate the diagnostic performance of the IGRA, we calculated the sensitivity and specificity of culture, radiologic imaging, polymerase chain reaction testing, fine needle aspiration, and excisional biopsy.

RESULT

Of the 271 adult patients with suspected TB lymphadenitis, 42 were diagnosed with the disease. The overall sensitivity and specificity of the IGRA were 78.8% and 95.5%, respectively. When the cutoff value of IFN-γ was set to 0.26 IU/mL, it met the inclusion criteria for suspicious TB lymphadenitis, with sensitivity and specificity of 83.3% and 95.1%, respectively.

CONCLUSIONS

The IGRA is useful in diagnosing TB lymphadenitis, with high sensitivity and specificity.

LEVEL OF EVIDENCE

4.

Performance of Xpert MTB/RIF in the diagnosis of tuberculous mediastinal lymphadenopathy by endobronchial ultrasound

RATIONALE

The Xpert (GeneXpert) MTB/RIF, an integrated polymerase chain reaction assay, has not been systematically studied in extrapulmonary and in particular mediastinal tuberculosis (TB).

OBJECTIVES

To investigate the performance of Xpert MTB/RIF in the diagnosis of intrathoracic nodal TB in a large tertiary urban medical center in the UK.

METHODS

We collected clinical, cytological, and microbiological data from two cohorts: 116 consecutive patients referred with mediastinal lymphadenopathy with detailed diagnostic information obtained, and an immediately subsequent second cohort of 52 consecutive patients with microbiologically confirmed mediastinal TB lymphadenopathy. All data were derived between January 2010 and October 2012. All patients underwent endobronchial ultrasound and transbronchial needle aspiration (TBNA). The performance of a single Xpert MTB/RIF assay alongside standard investigations, cytology, and microscopy/culture was evaluated against culture-confirmed TB.

MEASUREMENTS AND MAIN RESULTS

Microbiologically confirmed TB mediastinal lymphadenopathy was diagnosed in a total of 88 patients from both cohorts. Three culture-negative cases with associated caseating granulomatous inflammation on TBNA were given a probable diagnosis. A single Xpert MTB/RIF assay demonstrated overall sensitivity for culture-positive TB of 72.6% (62.3-81.0%). Xpert specificity from cohort 1 was 96.3% (89.1-99.1%). The positive predictive value was 88.9% (69.7-97.1%), negative predictive value was 86.5% (76.9-92.1%), and odds ratio was 51.3 (24.0-98.0) for correctly identifying culture-positive disease. Xpert captured all microscopy-positive cases (14 of 14) and the majority of microscopy-negative cases (48 of 71, 67.6%). Among the cases that were culture positive by TBNA, Xpert identified two-thirds of the multiple drug-resistant TB cases, leading to immediate regimen change up to 5 weeks ahead of positive cultures. The use of Xpert combined with cytology increased the sensitivity to 96.6%.

CONCLUSIONS

Xpert MTB/RIF provides a rapid, useful, and accurate test to diagnose mediastinal nodal TB in intermediate-incidence settings. The additional use of TBNA cytology further enhances the sensitivity of Xpert. This combination can facilitate rapid risk assessment and prompt TB treatment.

Concentration of lymph node aspirate improves the sensitivity of acid fast smear microscopy for the diagnosis of tuberculous lymphadenitis in Jimma, southwest Ethiopia

Background

Tuberculous lymphadenitis (TBLN) is the most common form of extrapulmonary tuberculosis. The cytomorphological features of lymph node smears have reduced specificity for the diagnosis of tuberculosis. The diagnosis of TBLN with direct smear microscopy lacks sensitivity due to the limited number of bacilli in lymph node aspirate. Therefore, we aimed to assess whether the concentration of lymph node aspirate improves the sensitivity of acid fast smear microscopy for the diagnosis of tuberculous lymphadenitis.

Methods

A cross-sectional comparative study was conducted on 200 patients clinically suspected for tuberculous lymphadenitis in Jimma, Ethiopia. Lymph node aspirate was collected. The first two drops were used for cytomorphological study and direct acid fast staining. The remaining aspirate was treated with N-acetyl-L-cysteine (NALC) and concentrated by centrifugation at 3000 g for 15 minutes. The sediment was used for acid fast staining and culture. Differentiation of M. tuberculosis complex (MTBC) from non-tuberculous mycobacteria (NTM) was done by para-nitrobenzoic acid susceptibility test.

Result

Complete data were available for 187 study subjects. 68% (127/187) were positive for M. tuberculosis on culture. Four isolates, 2.1% (4/187), were identified as NTM. The detection rate of direct smear microscopy was 25.1% and that of the concentration method 49.7%. Cytomorphologically, 79.7% of cases were classified as TBLN. The sensitivity of direct smear microscopy was 34.6%, for concentrated smear microscopy 66.1%, and for cytomorphology 89.8%. Two AFB positive cases on concentration method were non-tuberculosis mycobacteria (NTM). The concentration method yielded a positive result from seven cases diagnosed as suppurative abscess by cytology. Both for the direct and concentration methods the highest rate of AFB positivity was observed in smears showing caseous necrosis alone. Smear positivity rate decreased with the appearance of epithelioid cell aggregates.

Conclusion

The concentration of lymph node aspirates for acid fast smear microscopy had significantly higher sensitivity than direct microscopy.

Cytopathological Pattern of Tubercular Lymphadenopathy on FNAC: Analysis of 550 Consecutive Cases

BACKGROUND

Fine needle aspiration cytology (FNAC) of lymph nodes is a simple, cost effective, out-patient procedure used for diagnosis of various causes of lymphadenopathies. In tuberculous lymphadenitis, it not only used for the cytological diagnosis but also used for other ancillary testing such as Ziehl- Neelsen staining and AFB Culture.

AIMS

Our study was designed to evaluate the cytopathological pattern of FNAC aspirate of patients presenting with lymphadenopathy with special reference to tuberculous lymphadenopathy.

MATERIALS AND METHODS

In this study all the patients referred to the cytopathology lab for FNAC of lymph nodes between January 2011 to June, 2013 were included. Out of 1050 patients presenting with lymphadenopathies, there were 550 cases of tuberculous lymphadenitis. The cytopathological findings of these 550 cases were analyzed.

RESULTS

A female preponderance was noted in our study with maximum incidence in the 3rd decade. Cervical lymph nodes were the most common nodes to be involved. Gross examination of aspirate showed maximum cases (74.5.2%) of whitish material. Among the four cytological patterns on FNAC, maximum cases demonstrated caseous necrotic material with degenerated inflammatory cells. Ziehl- Neelsen staining showed overall AFB positivity of 44.54%. Maximum AFB positivity was seen in cases having caseous necrosis only.

CONCLUSION

FNAC is a simple, cost effective technique with high degree of accuracy in diagnosing Tubercular Lymphadenitis. Despite certain limitations and pitfalls, FNAC coupled with Ziehl- Neelson staining should be the 1st line investigation in cases with lymphadenopaty, in a developing country with high prevalence rate of tuberculosis.

Clinico-pathological features of tuberculosis due to Mycobacterium tuberculosis Uganda genotype in patients with tuberculous lymphadenitis: a cross sectional study

Background

Tuberculous lymphadenitis is next to pulmonary tuberculosis as the most common cause of tuberculosis. Uganda genotype, one of the sub-lineages of Mycobacterium tuberculosis, is the most prevalent cause of pulmonary tuberculosis in Uganda. We here investigate the clinicopathological characteristics of patients with tuberculous lymphadenitis infected with M. tuberculosis Uganda genotype compared with those infected with M. tuberculosis non-Uganda genotype strains.

Methods

Between 2010 and 2012, we enrolled 121 patients (mean age 28.5 yrs, male 48%; female 52%) with tuberculous lymphadenitis, and categorized them by their M. tuberculosis genotypes. The clinical features and lymph node cytopathological parameters were compared between patients in the Uganda and non-Uganda categories using a crude and multivariable logistic regression model with adjustment for confounding factors.

Results

Of the 121participants, 56 (46%) were infected with strains of Uganda genotype. Patients infected with this genotype had significantly lower frequency of abdominal lymphadenopathy (odds ratio 0.4, p = 0.046) after adjusting for sex, age and HIV. Abdominal lymphadenopathy was also significantly associated with abnormal chest X-ray (p = 0.027).

Conclusion

Tuberculous lymphadenitis patients infected with M. tuberculosis Uganda genotype were significantly less prone to have abdominal lymphadenopathy indicating potential reduced ability to disseminate and supporting the concept that differences in M. tuberculosis genotype may have clinical implications.

Utility of acid-fast staining for detection of mycobacteria in cutaneous granulomatous tissue reactions

OBJECTIVES

Ancillary molecular testing on tissue is available for mycobacterial disease; however, judicious use of highly sensitive tests, such as polymerase chain reaction (PCR) and sequencing, should be guided by histologic parameters. We sought to investigate the utility of performing acid-fast stains (AFS) on skin biopsy specimens with granulomatous inflammation without an otherwise obvious histologic or clinical explanation.

METHODS

Our retrospective review identified 31 patients with biopsy specimens showing granulomatous inflammation that had simultaneous AFS and mycobacterial culture or PCR performed.

RESULTS

Biopsy specimens from eight (25.8%) patients had AFS interpreted as positive or suspicious for acid-fast bacilli. Eight had positive cultures and one had positive PCR. One biopsy specimen with AFS that showed occasional acid-fast structures that were interpreted as "suspicious" for mycobacteria was associated with a negative culture and negative PCR. Three (9.7%) biopsy specimens with negative AFS had positive cultures, and 19 (61.3%) biopsy specimens with negative AFS also had negative culture results. In our biopsy specimens, sensitivity of AFS was 72.7% and specificity was 95.0%. Positive predictive value of AFS was 88.9%, and negative predictive value was 86.4%.

CONCLUSIONS

AFS has good sensitivity and excellent specificity and should be performed on all unexplained granulomatous tissue reactions of skin in conjunction with mycobacterial culture.

A Case of DisseminatedMycobacterium aviumInfection in a Dog in Greece

A Basset Hound dog was presented with anorexia, fever, diarrhea, significant level of splenomegaly, and enlargement of mesenteric and superficial lymph nodes. Cytology of fine-needle-aspiration material, obtained from popliteal lymph node, revealed macrophages with intracytoplasmic, nonstaining, slender, rod-like structures, indicative of mycobacteria. Bacterial culture of lymph node aspirated material produced a colony which by means of molecular techniques (PCR amplification and hybridization of PCR products) was subsequently identified asMycobacterium avium. This is the first report of disseminatedM. aviuminfection in a dog in Greece.

Tuberculous lymphadenitis in Northern Ethiopia: in a public health and microbiological perspectives

Background

The actual burden and causative agent of tuberculous lymphadenitis (TBLN) cases is not well known due to lack of strong surveillance system and diagnostic facilities in Ethiopia. This study was conducted to determine the prevalence of TBLN, its causative agent and risk factors for acquiring this infection.

Methods

A cross-sectional study was conducted from April to May 2012 at four main hospitals and one diagnostic clinic located in northern Ethiopia. Fine needle aspirates (FNAs) from TBLN suspects were taken for acid fast bacilli (AFB) microscopy, culture and molecular typing.

Results

Among 437 aspirates, culture yielded AFB in 226 (51.7%) of cases. Sixty one culture negative cases (30.5% of 200 cases) were positive by Xpert MTB/RIF test. Moreover, a rifampicin resistant AFB was detected from culture negative cases. The overall prevalence of FNAs positive TBLN cases was 65.8 %. The BacT/AlerT 3D system proved to be a more rapid method with higher recovery rate than Lowenstein-Jensen (L-J) and/or Gottsacker media (P<0.0001). Molecular typing identified all culture positive isolates as M.tuberculosis. The main risk factors for TBLN were pediatric age (OR 2.8, 95% CI, 1.09- 7.05) and cough (OR 2, 95%CI, 1.09-3.7).

Conclusions

The results of this study revealed a high prevalence of TBLN in the study sites and that pediatric age and cough are key predictors of the disease. TBLN is an important public health problem that needs to be addressed in the area. It is important to note that MDR strains of TB could be involved and aetiological confirmation and drug sensitivity testing of TBLN isolates should be expanded. Further studies on the M.tuberculosis lineages, circulating strains and transmission dynamics, are recommended.

Endobronchial ultrasound-guided transbronchial needle aspiration in diagnosing intrathoracic tuberculosis

BACKGROUND

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure that has enabled mediastinal and hilar lymph node assessment with a high sensitivity, but its role in the diagnosis of intrathoracic tuberculosis (TB) has not been established.

METHODS

We prospectively studied 59 patients suspected of having TB with thoracic lymph node lesions or intrapulmonary lesions accessible by EBUS-TBNA at a clinical center for thoracic medicine from January 2010 to December 2011. Bronchoscopic findings, EBUS-TBNA procedures, pathologic findings, and microbiologic results were recorded.

RESULTS

Of 59 eligible patients, 41 patients had TB, 5 had lung cancer, 7 had inflammation, and 6 had sarcoidosis. Sensitivity was 85%, specificity was 100%, positive and negative predictive values were 100% and 75%, respectively, and accuracy was 90% by EBUS-TBNA for TB. Pathologic findings were consistent with TB in 80% of patients (33 of 41), and in 27% (11 of 41) the smear was positive. A total of 37 patients with TB had cultures, of whom 17 (46%) were positive. There were 80 mediastinal and hilar lymph nodes and 5 intrapulmonary lesions that were biopsied in the 41 patients with TB. Multivariate logistic regression revealed that short-axis diameter was an independent risk factor associated with positive pathology, smear, and culture (p < 0.05). Additionally, pathology showing necrosis was an independent risk factor associated with a positive culture.

CONCLUSIONS

Endobronchial ultrasound-guided transbronchial needle aspiration has a high diagnostic yield in the investigation of suspected intrathoracic TB by means of aspiration of intrathoracic lymph nodes and tracheobronchial wall-adjacent lung lesions.

Fine-needle aspiration cytology in Ethiopia

CONTEXT

Most of the population in Ethiopia lives below the poverty line with severely limited access to health care. The burden of infectious diseases is high, but benign and malignant neoplasms are also encountered frequently. For diagnosis of palpable lesions in this setting, fine-needle aspiration biopsy is the method of choice.

OBJECTIVE

To present findings from several patients from 3 major hospitals in Ethiopia who underwent fine-needle aspiration biopsy.

DATA SOURCES

Representative cytopathology cases of routinely encountered problems are shown. Often patients present with clinically advanced lesions. Staffing, technique, and equipment used for fine-needle aspiration biopsy are described at Black Lion Hospital (Addis Ababa), the University of Gonder Hospital (Gonder), and Ayder Referral Hospital of Mekelle University in the Tigray region of northern Ethiopia.

CONCLUSIONS

Fine-needle aspiration biopsy is a highly effective method for diagnosis of mass lesions, especially in an environment with sparse health care resources, such as Ethiopia. This article illustrates the work of Ethiopian cytopathologists and emphasizes the constraints under which they perform their work.

Prevalence of tuberculous lymphadenitis in Gondar University Hospital, Northwest Ethiopia

Background

Tuberculous is the leading cause of death worldwide with a large number of deaths occurring in developing countries. Tuberculous lymphadenitis is among the most common presentations of extra pulmonary tuberculous. This study attempts to determine the magnitude of tuberculous lymphadenitis from patients with lymph node aspirate in Gondar University Hospital, Northwest Ethiopia.

Methods

Retrospective study was conducted. Data were collected from registration book of Gondar university Hospital pathology laboratory after checking the completeness of patient’s necessary information like age, sex and fine needle aspiration cytology results. Data were entered and analyzed using SPSS version 16 statistical package. Chi-square test was done to determine associations.

Result

A total of 3,440 lymph node aspirates were examined using fine needle aspiration cytology. Of these, 2,392 (69.5%) cases were found to have tuberculous lymphadenitis. Male 1647(47.9%) to female 1793(52.1%) ratio of all study subjects were 0.9:1. Females (54.1%) were more affected than males (45.9%). Age, sex and site of aspiration were found to be statistically associated with tuberculous lymphadenitis (p-value < 0.001). The age group of 15–24 years had the highest prevalence of tuberculous lymphadenitis followed by those of 25–34 years old. The most affected sites were cervical lymph nodes (47.5%) followed by auxiliary (19.4%) and submandibular (12.9%) lymph node regions. None of the records documented the HIV status of subjects.

Conclusion

The prevalence of tuberculous from lymph node aspirate was found to be higher involving the frequently affected site of cervical lymph node. The HIV status of patients with all forms of tuberculous should have to be checked and documented. Further prospective and advanced studies are recommended to determine the specific etiologic agents and contributing factors.

Rapid culture diagnosis of tuberculous lymphadenitis from a tertiary care centre in an endemic nation: potential and pitfalls

In spite of low sensitivity and specificity, standard diagnostic algorithm recommends fine needle aspiration cytology (FNAC) and direct microscopic screening for acid-fast bacilli (AFB) for the routine diagnosis of tuberculous lymphadenopathy (LNTB). In this study, the diagnostic utility of liquid broth based automated culture (BacT/ALERT 3D) technique was assessed in comparison with conventional techniques in 89 clinically suspected tubercular lymphadenitis patients. 60% (n = 53) were positive by FNAC and 38.4% (n = 34) demonstrated AFB in smear examination. BacT/ALERT yielded isolation in 43.1% (n = 38) aspirates, confirming tubercular aetiology. We also found six paediatric culture-positive cases which showed negative outcome by both FNAC and smear. Thus, we conclude that culture by BacT/ALERT, may be used for faster yield of Mycobacteria in LNTB, especially in children. Additionally, this could also be used as a platform for further differentiation of Mycobacterium tuberculosis from non-tuberculous mycobacteria (NTM) infection and for testing of anti-tubercular chemotherapeutic agents whenever drug resistance is suspected.

Magnitude of gene mutations conferring drug resistance in mycobacterium tuberculosis isolates from lymph node aspirates in ethiopia

OBJECTIVE

Resistance to drugs is due to particular genomic mutations in the specific genes of Mycobacterium tuberculosis. Timely genetic characterization will allow identification of resistance mutations that will optimize an effective antibiotic treatment regimen. We determine the magnitude of gene mutations conferring resistance to isoniazid (INH), rifampicin (RMP) and ethambutol (EMB) among tuberculosis (TB) lymphadenitis patients.

METHODS

A cross sectional prospective study was conducted among 226 M.tuberculosis isolates from culture positive lymph node aspirates collected from TB lymphadenitis patients between April 2012 and May 2012. Detection of mutations conferring resistance to drugs was carried out using GenoType(®) MTBDRplus and GenoType® MTBDRsl assay.

RESULTS

Out of the 226 strains, mutations conferring resistance to INH, RMP, multidrug resistance tuberculosis (MDR-TB) and EMB were 8, 3, 2 and 2 isolates, respectively. There was no isolated strain that showed mutation in the inhA promoter region gene. All INH resistant strains had mutations in the katG gene at codon 315 with amino acid change of S315T1. Among rifampicin resistant strains, two isolates displayed mutations at codon 531 in the rpoB gene with amino acid change of S531L and one isolate was by omission of wild type probes at Q513L. According to mutations associated with ethambutol resistance, all of the isolates had mutations in the embB gene with aminoacid change of M306I. All isolates resistant to INH, RMP and MDR using BacT/AlerT 3D system were correctly identified by GenoType® MTBDRplus assay.

CONCLUSION

We observed mutations conferring resistance to INH at S315T1 of the katG gene, RMP at S531L and Q513L in the rpoB genes and EMB at M306I of the embB gene. In the absence of conventional drug susceptibility testing, the effort to develop easy, rapid and cost effective molecular assays for drug resistance TB monitoring is definitely desirable and the GenoType® MTBDRplus assay was found to be a useful method for diagnosis of resistance to INH, RMP and MDR from lymph node aspirates. Further molecular cluster analysis to determine transmission dynamics of mutated strain is required.