scholarly journals Diagnostic Performance of Xpert MTB/RIF in Bronchoalveolar Lavage of Sputum-Scarce Recurrent Pulmonary Tuberculosis Cases

2020 ◽  
Vol 10 (02) ◽  
pp. 74-78
Author(s):  
Pratibha Sharma ◽  
Abhishek Kumar ◽  
Mamatha S. ◽  
Ranganath T. Ganga
Keyword(s):  
Bronchoalveolar Lavage ◽  
Predictive Value ◽  
Diagnostic Performance ◽  
Nontuberculous Mycobacteria ◽  
Cross Reactivity ◽  
Rifampicin Resistance ◽  
Nontuberculous Mycobacterium ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Composite Reference Standard

Abstract Introduction Xpert MTB/RIF has greater sensitivity and specificity than smear microscopy. Bronchoalveolar lavage (BAL) is safe and valuable tool in sputum-scarce and sputum-negative tuberculosis (TB) patients. Our study evaluated the performance of Xpert in BAL specimen of sputum-scarce recurrent TB cases exclusively. Materials and Methods Sputum-scarce recurrent TB patients who underwent BAL between July 2018 and July 2019 were included. The diagnostic performance of Xpert and acid-fast bacilli (AFB) smear examination in BAL specimen was compared with liquid culture Mycobacterium TB (MTB) and composite reference standard. Results A total of 126 patients were included in the study. MTB culture was positive in 70 cases and nontuberculous mycobacteria were seen in five cases. Xpert was positive was in 63 patients. Sensitivity of Xpert and AFB smear was 84.29% (95% confidence interval [CI]: 73.62–91.89) and 18.57% (95% CI: 10.28–29.66), respectively, with p < 0.001 proving the superiority of Xpert. Xpert had a specificity of 97.96 (89.15–99.95), positive predictive value of 93.65% (95% CI 85.19–97.42), and negative predictive value of 80.36% (95% CI: 70.26–87.63). Smear had a specificity of 91.84% (95% CI: 80.21–97.58) against 97.96 (89.15–99.95) of Xpert, and smear was positive in nontuberculous mycobacterium cases as well. Xpert showed no cross-reactivity between mycobacterial species. Rifampicin resistance was seen in 8 (12.69%) cases, and 21 patients had other diagnoses. Conclusion Xpert has greater sensitivity in comparison to AFB smear in BAL specimen. Sputum-scarce recurrent TB cases have a similar chance of rifampicin resistance as sputum smear-positive cases should undergo BAL for Xpert analysis routinely.

scholarly journals EVALUATION OF MODIFIED CYTOSPIN SLIDE MICROSCOPY FOR DETECTION OF ACID FAST BACILLI IN BRONCHOALVEOLAR LAVAGE FLUID FOR DIAGNOSIS OF PULMONARY TUBERCULOSIS

2021 ◽  
Vol 71 (3) ◽  
pp. 920-23
Author(s):  
Anam Imtiaz ◽  
Aamer Ikram ◽  
Gohar Zaman ◽  
Luqman Satti ◽  
Fatima Sana
Keyword(s):  
Positive Predictive Value ◽  
Bronchoalveolar Lavage ◽  
Negative Predictive Value ◽  
Predictive Value ◽  
Armed Forces ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Becton Dickinson ◽  
Acid Fast Bacilli ◽  
Sensitivity Specificity

Objective: To evaluate the cytospin slide microscopy method for detection of acid fast bacilli (AFB) in bronchoalveolar lavage (BAL) fluid comparing it with concentrated smear microscopy. Study Design: Cross-sectional validation study. Place and Duration of Study: Department of Microbiology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from Dec 2016 to Sep 2018. Methodology: BAL specimens from suspected tuberculosis patients who were sputum smear negative, submitted to AFIP for diagnosis were included in the study. Smears for microscopy were prepared with the modified cytospin method as well as the standard concentrated technique. The prepared smears from both methods were stained with Ziehl–Neelsen (ZN) staining method and examined under 100 × oil immersion lens. TB culture performed on BACTEC MGIT 960 automated culture system (Becton Dickinson, USA) was taken as gold standard for TB diagnosis. The two methods were compared in terms of sensitivity, specificity, positive predictive value and negative predictive value. Results: Out of the 130 samples tested, 62 (47.7%) were positive on culture using MGIT 960 system. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of the modified cytospin method for pulmonary TB diagnosis was found to be 68.3%, 100%, 100%, 77% and 84.6%, respectively. Conclusion: The sensitivity of the modified cytopsin smear method was significantly higher than that of the concentrated method. The study concludes that this is a simpler and more accurate method for BAL fluid microscopy.

scholarly journals A Retrospective Cross-Sectional Study of the Utility of Cartridge-Based Nucleic Acid Amplification Test in Diagnosis of Pulmonary and Extrapulmonary Tuberculosis in People Living with HIV in Second Highest HIV Prevalent State in India

2021 ◽  
Author(s):  
Tade Bagbi ◽  
Ningthoukhongjam Reema ◽  
S. Bhagyabati Devi ◽  
Thangjam Gautam Singh ◽  
Mohammad Jaleel ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Cross Sectional Study ◽  
Nucleic Acid Amplification Test ◽  
Nucleic Acid Amplification ◽  
Rifampicin Resistance ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Sectional Study ◽  
Cross Sectional ◽  
Smear Negative

Abstract Introduction Tuberculosis (TB) in people living with human immunodeficiency virus (PLHIV) is difficult to diagnose due to fewer organisms in sputum and extrapulmonary samples. Sputum culture takes 4 to 8 weeks for growth of the mycobacteria. Delayed treatment for TB in PLHIV leads to increased mortality. This study evaluated cartridge-based nucleic acid amplification test (CBNAAT) as a diagnostic tool for diagnosis of pulmonary TB (PTB) and extrapulmonary TB (EPTB) in PLHIV in the second most HIV prevalent state in India and for comparing its efficacy between Ziehl–Neelsen (ZN) staining sputum smear–positive and sputum smear–negative TB. Methods This cross-sectional study was conducted in RIMS, Imphal, with 167 PLHIV patients, age 15 years or older, having signs and symptoms of TB. Appropriate samples for sputum microscopy and CBNAAT were sent. Conclusion The overall sensitivity of sputum smear for acid-fast bacillus (AFB) was found to be 30.71% and that of CBNAAT was 38.57%. Sensitivity of CBNAAT for sputum smear–positive and sputum smear–negative TB was 100 and 11.3%, respectively. Sensitivity of ZN smear for AFB of EPTB sample was 48.1% and that of CBNAAT was 59.25%. In both PTB and EPTB, CBNAAT showed an increase in diagnosis of microbiologically confirmed PTB cases by 7.8 and 11.1%, respectively, over and above the cases diagnosed by ZN smear microscopy. Rifampicin resistance was detected in five patients. We conclude that CBNAAT is a rapid test with better sensitivity in diagnosis of PTB and EPTB in PLHIV, compared with ZN smear microscopy. It detects rifampicin resistance for multidrug-resistant TB and helps in early treatment intervention.

Blinded Rechecking of AFB smear Microscopy performance in Selected private health facilities in Tigray, Northern Ethiopia

2020 ◽  
Author(s):  
Letebrhan Weldemhret
Keyword(s):  
Predictive Value ◽  
Cost Effective ◽  
Cross Sectional Study ◽  
Health Facilities ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Northern Ethiopia ◽  
Major Error ◽  
Cross Sectional ◽  
Tigray Region

Abstract Background: Sputum smear microscopy remains the most cost-effective tool for tuberculosis diagnosis and treatment monitoring in resource constrained settings. Random blinded rechecking is a reliable tool to measure and improve smear microscopy. So, this study was intended to assess random blinded rechecking of AFB smear microscopy performance in selected private health facilities in Tigray region, Northern Ethiopia.Methods: A cross sectional study was conducted from April 1st 2017 to May 30, 2017. The data was collected using standard data collection form. Statistical analysis was done using SPSS version 25 and the reading agreement was done using kappa statistics.Results: Of the total 269 blinded rechecked smears, 4.8% was found discrepant findings. The major and minor errors were reported by 2.6% (7/269) and 2.2% (6/269) respectively. Likewise, the major error was reported by 50% (5/10) of health facilities with microscopic center. Overall, the sensitivity, specificity, positive predictive value, and negative predictive value of the blinded rechecking smears were 87.5%, 98%, 89.7% and 97.8%, respectively with substantial reading agreement, kappa value= 0.80.Conclusions: The overall performance of blinded rechecking was satisfactory with good smear reading agreement. But, the major error reported indicated unacceptable performance. To minimize the discrepancy, private health facilities with tuberculosis smear microscopic center should adhere to national tuberculosis guidelines.

scholarly journals Nontuberculous Mycobacteria Isolated from Tuberculosis Suspects in Ibadan, Nigeria

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Simeon Idowu Cadmus ◽  
Bassirou Diarra ◽  
Brehima Traore ◽  
Mamoudou Maiga ◽  
Sophia Siddiqui ◽  
...  
Keyword(s):  
Latin American ◽  
Nontuberculous Mycobacteria ◽  
Positive Culture ◽  
Diagnostic Algorithm ◽  
Molecular Techniques ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Precise Diagnosis ◽  
Directly Observed Treatment ◽  
Ibadan Nigeria

In Nigeria, one of the highest tuberculosis (TB) burdened nations, sputum smear microscopy is routinely employed for TB diagnosis at Directly Observed Treatment Short-Course (DOTS) Centers. This diagnostic algorithm does not differentiateMycobacterium tuberculosiscomplex (MTC) from nontuberculous mycobacteria (NTM). Between December 2008 and January 2009, consecutive patients diagnosed with TB were screened for inclusion at 10 DOTS centers in Ibadan, Nigeria. To verifyMycobacteriumspecies in patients diagnosed, we cultured and identified mycobacterial isolates using PCR, line probe assay, and spoligotyping techniques. From 48 patients screened, 23 met the inclusion criteria for the study. All the 23 study patients had a positive culture. Overall, we identified 11/23 patients (48%) with MTC only, 9/23 (39%) with NTM only, and 3/23 (13%) with evidence of both MTC and NTM. Strains of MTC identified were Latin American Mediterranean (LAM) genotype (n=12),M. africanum(n=1), and the genotype family T (n=1). FourM. avium-intracellulare-M. scrofulaceum complexes, oneM. chelonae complex, oneM. abscessus, and oneM. intracellularewere identified. Our findings underscore the need to incorporate molecular techniques for more precise diagnosis of TB at DOTS centers to improve clinical outcomes and safe guard public health, particularly in TB endemic countries.

Fluorescein diacetate and rapid molecular testing for the early identification of rifampicin resistance in Mali

2020 ◽  
Vol 24 (8) ◽  
pp. 763-769
Author(s):  
B. Diarra ◽  
T. Decroo ◽  
A. Somboro ◽  
G. Coulibaly ◽  
M. Tolofoudie ◽  
...  
Keyword(s):  
Predictive Value ◽  
Early Identification ◽  
Fluorescein Diacetate ◽  
Rifampicin Resistance ◽  
Smear Microscopy ◽  
Molecular Testing ◽  
Full Spectrum ◽  
Pulmonary Tb ◽  
Resistant Tuberculosis ◽  
Baseline Screening

BACKGROUND: Non-conversion on auramine smear microscopy indicates a lack of treatment response, possibly associated with initial rifampicin-resistant tuberculosis (RR-TB). However, dead bacteria still stain positive and may be detected. Fluorescein diacetate smear microscopy (FDA) shows live mycobacteria only. Therefore, we studied the potential of 2-month (2M) FDA for the identification of initial RR-TB.METHODS: Between 2015 and 2018, we enrolled new smear-positive pulmonary TB patients from five local centres in Bamako, Mali. After baseline screening, sputum samples were collected at 1M, 2M, 5M and 18M. We used rpoB sequencing to identify initial RR-TB.RESULTS: Of 1359 patients enrolled, 1019 (75%) had rpoB sequencing results. Twenty-six (2.6%, 95%CI: 1.7–3.7) had mutations conferring rifampicin resistance. Most frequent rpoB mutations were located at the codons Asp435Val (42.4%) and Ser450Leu (34.7%). Among patients with initial RR-TB, 72.2% were FDA-negative at 2M (P = 0.2). The positive and negative predictive value of 5M FDA for culture-based failure was respectively 20.0% and 94.7%.CONCLUSION: FDA did not identify the majority of patients with initial RR-TB or culture-based failure. As the full spectrum of mutations identified on sequencing was identified using Xpert, our data support its rapid universal implementation in Mali.

scholarly journals Diagnostic Performance of Xpert MTB/RIF Assay Versus Ziehl-Neelsen Method for the Diagnosis of Pulmonary Tuberculosis in Addis Ababa, Ethiopia

2018 ◽  
Vol 12 (1) ◽  
pp. 390-396
Author(s):  
Boja D. Taddese ◽  
Daniel M. Desalegn ◽  
Abay S. Misganaw ◽  
Kumera T. Kitila ◽  
Tinsae Kidanemariam Hailu ◽  
...  
Keyword(s):  
Pulmonary Tuberculosis ◽  
Predictive Value ◽  
Gold Standard ◽  
Addis Ababa ◽  
Public Health Problem ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Sputum Smear Microscopy ◽  
Cross Sectional ◽  
Sensitivity Specificity

Background: Worldwide Tuberculosis (TB) is the ninth leading cause of death from a single infectious agent, positioning on top of Human Immuno Deficiency Virus (HIV) and it is still an eminently serious public health problem. In developing countries, Ziehl-Neelsen (ZN)-stained sputum smear microscopy is the most widely used diagnostic method in diagnosing Pulmonary Tuberculosis (PTB). This study was aimed to compare the diagnostic performances of ZN-method with Xpert MTB/RIF assay for the diagnosis of PTB in Addis Ababa, Ethiopia. Methods: Facility-based cross-sectional study design was conducted from September 2016 to June 2017 on a total of 244 sputum samples collected from presumptive TB patients. The L-J sputum culture was used as a gold standard to compare the diagnostic performances of Xpert MTB/RIF assay and ZN-methods. Kappa values were analyzed by using statistical package for Social Science (SPSS) version 20 software at 95% Confidence Interval (CI). The Sensitivity, Specificity, Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of ZN-stained sputum smear microscopy and Xpert MTB/RIF assay were calculated against the gold standard. Results: The Sensitivity, Specificity, PPV and NPV of ZN-stained sputum smear microscopy were 68.38%, 95.28%, 93.02% and 76.58% respectively, while for Xpert MTB/ RIF assay were 88.89%, 81.89%, 81.89% and 88.89% respectively. The results of the two diagnostic approaches were concordant with the gold standard with a kappa value of ZN 0.650 and 0.743 for Xpert MTB/RIF assay. Conclusion: This study concludes that the sensitivity of Xpert MTB/RIF assay was better than ZN-stained direct sputum smear microscopy for the diagnosis of pulmonary tuberculosis.

scholarly journals Study the usefulness of cartridge based nuclear acid amplification test in bronchoalveolar lavage samples in the diagnosis of smear-negative/non sputum producing patients with suspected tuberculosis

2019 ◽  
Vol 7 (3) ◽  
pp. 886
Author(s):  
K. Raj Kumar ◽  
Sony Reddy ◽  
Raghu Vamsi
Keyword(s):  
Bronchoalveolar Lavage ◽  
Diagnostic Yield ◽  
High Sensitivity ◽  
Diagnostic Value ◽  
Nucleic Acid Amplification ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Pulmonary Medicine ◽  
Additional Advantage ◽  
Smear Negative

Background: The aim of study is to evaluate the diagnostic value of the CBNAAT in BAL samples of smear negative for AFB or who could not produce an expectorated sputum sample.Methods: A prospective and observational study of in patient and out patient department in Department of Pulmonary Medicine of Chalmeda Anand Rao Institute of Medical Sciences, Karimnagar during the period November 2017 to November 2018.Results: Bronchoalveolar lavage cartridge based nucleic acid amplification test in bronchoalveolar lavage was done for 60 samples of patients who were having history and chest x-ray suggestive of pulmonary tuberculosis with sputum AFB negative. Out of these sputum negative samples 25 were BAL CBNAAT positive and rest were negative.Conclusions: CBNAAT adds significantly to the diagnostic yield of PTB in comparison to sputum smear microscopy. It has additional advantage of identifying rifampicin resistance with high sensitivity and specificity.

scholarly journals Smear Microscopy for Diagnosis of Pulmonary Tuberculosis in Eastern Sudan

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Yassir A. Shuaib ◽  
Eltahir A. G. Khalil ◽  
Ulrich E. Schaible ◽  
Lothar H. Wieler ◽  
Mohammed A. M. Bakheit ◽  
...  
Keyword(s):  
Pulmonary Tuberculosis ◽  
Positive Predictive Value ◽  
Predictive Value ◽  
Clinical Symptoms ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Reference Laboratory ◽  
Middle Income ◽  
Culture Positive ◽  
Eastern Sudan

Background. In Sudan, tuberculosis diagnosis largely relies on clinical symptoms and smear microscopy as in many other low- and middle-income countries. The aim of this study was to investigate the positive predictive value of a positive sputum smear in patients investigated for pulmonary tuberculosis in Eastern Sudan. Methods. Two sputum samples from patients presenting with symptoms suggestive of tuberculosis were investigated using direct Ziehl-Neelsen (ZN) staining and light microscopy between June to October 2014 and January to July 2016. If one of the samples was smear positive, both samples were pooled, stored at −20°C, and sent to the National Reference Laboratory (NRL), Germany. Following decontamination, samples underwent repeat microscopy and culture. Culture negative/contaminated samples were investigated using polymerase chain reaction (PCR). Results. A total of 383 samples were investigated. Repeat microscopy categorized 123 (32.1%) as negative, among which 31 were culture positive. This increased to 80 when PCR and culture results were considered together. A total of 196 samples were culture positive, of which 171 (87.3%), 14 (7.1%), and 11 (5.6%) were M. tuberculosis, M. intracellulare, and mixed species. Overall, 15.6% (57/365) of the samples had no evidence of M. tuberculosis, resulting in a positive predictive value of 84.4%. Conclusions. There was a discordance between the results of smear microscopy performed at local laboratories in the Sudan and at the NRL, Germany; besides, a considerable number of samples had no evidence of M. tuberculosis. Improved quality control for smear microscopy and more specific diagnostics are crucial to avoid possible overtreatment.

scholarly journals Diagnosing sputum smear negative pulmonary tuberculosis patients by transbronchial biopsy and bronchoalveolar lavage smear.

2020 ◽  
Vol 27 (03) ◽  
pp. 499-505
Author(s):  
Mahwish Niaz ◽  
Mumtaz Ahmad ◽  
Kanwal Fatima ◽  
Faiza Kazi ◽  
Hassan Salim ◽  
...  
Keyword(s):  
Pulmonary Tuberculosis ◽  
Diagnostic Accuracy ◽  
Bronchoalveolar Lavage ◽  
Disease Transmission ◽  
Predictive Value ◽  
Transbronchial Biopsy ◽  
Sputum Smear ◽  
Cross Sectional ◽  
Tuberculosis Patients ◽  
Smear Negative

Pulmonary tuberculosis is one of the leading causes of infectious disease related mortality. Transbonchial biopsy and bronchoalveolar lavage smear obtained by bronchoscopy provides greater quantity of material for analysis, thus increases the chances of diagnosing the disease. Objectives: To diagnose sputum smear negative pulmonary tuberculosis patients by Transbronchial Biopsy and Bronchoalveolar smear keeping bronchoalvelar lavage culture as gold standard. To calculate and compare the diagnostic accuracy of transbronchial biopsy and bronchoalveolar lavage smear in sputum negative patients. Study Design: Cross-sectional validation study. Setting: Department of histopathology, Foundation University Medical College, Islamabad and Department of Pulmonology and Microbiology, Fauji Foundation Hospital, Rawalpindi. Period: From May 2016 to May 2017. Materials & Methods: It comprised 96 patients who underwent bronchoscopy. Transbronchial biopsy, bronchoalveolar lavage smear preparation and bronchoalveolar lavage culture was performed on specimens of all patients. Results: Out of 96 patients 22 (22.91%) patients were actually having tuberculosis whereas 74 (77%) had only clinical and radiological suspicion of tuberculosis. The mean age of patients was 43 years with a standard deviation of ±19.1 .The age range was 12-80 years. The sensitivity, specificity, positive predictive value, negative predictive value and true positives of transbronchial biopsy were 68.1%, 77%, 46.8%, 89% and15.62% while the values for bronchoalveolar lavage were 50%, 97.29%, 84.6%, 86.7% and 11.45% respectively. Thus, the diagnostic accuracy calculated for transbronchial biopsy and bronchoalveolar lavage was 75% and 13.54% respectively. Conclusions: Bronchoscopy should be done in all sputum negative tuberculosis patients having strong clinical and radiological suspicion to obtain transbronchial biopsy and bronchoalveolar lavage for timely diagnosis, treatment and prevention of disease transmission as well as to avoid empirical treatment and its side effects in patients having no tuberculosis. The diagnostic accuracy of transbronchial biopsy is almost 5 times more compared to bronchoalveolar lavage smear.

Sign in / Sign up

Export Citation Format

Share Document