scholarly journals Use of amplified Mycobacterium tuberculosis direct test in respiratory samples from HIV-infected patients in Brazil

2014 ◽  
Vol 40 (2) ◽  
pp. 148-154 ◽  
Author(s):  
Leonardo Bruno Paz Ferreira Barreto ◽  
Maria Cristina da Silva Lourenço ◽  
Valéria Cavalcanti Rolla ◽  
Valdiléia Gonçalves Veloso ◽  
Gisele Huf
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Predictive Value ◽  
Laboratory Diagnosis ◽  
Test Results ◽  
Tuberculosis Complex ◽  
Indicator Tube ◽  
Lowenstein Jensen ◽  
The Mean ◽  
Sensitivity Specificity ◽  
The City

OBJECTIVE: To compare the accuracy of the amplified Mycobacterium tuberculosis direct (AMTD) test with reference methods for the laboratory diagnosis of tuberculosis in HIV-infected patients. METHODS: This was a study of diagnostic accuracy comparing AMTD test results with those obtained by culture on Löwenstein-Jensen (LJ) medium and by the BACTEC Mycobacteria Growth Indicator Tube 960 (BACTEC MGIT 960) system in respiratory samples analyzed at the Bioassay and Bacteriology Laboratory of the Oswaldo Cruz Foundation Evandro Chagas Clinical Research Institute in the city of Rio de Janeiro, Brazil. RESULTS: We analyzed respiratory samples collected from 118 patients, of whom 88 (74.4%) were male. The mean age was 36.6 ± 10.6 years. Using the AMTD test, the BACTEC MGIT 960 system, and LJ culture, we identified M. tuberculosis complex in 31.0%, 29.7%, and 27.1% of the samples, respectively. In comparison with LJ culture, the AMTD test had a sensitivity, specificity, positive predictive value, and negative predictive value of 87.5%, 89.4%, 75.7%, and 95.0%, respectively, for LJ culture, whereas, in comparison with the BACTEC MGIT 960 system, it showed values of 88.6%, 92.4%, 83.8%, and 94.8%, respectively. CONCLUSIONS: The AMTD test showed good sensitivity and specificity in the population studied, enabling the laboratory detection of M. tuberculosis complex in paucibacillary respiratory specimens.

scholarly journals XPERT MYCOBACTERIUM TUBERCULOSIS/RIFAMPICIN ASSAY: A BOON IN TUBERCULOSIS DIAGNOSTICS

2016 ◽  
Vol 9 (5) ◽  
pp. 225 ◽  
Author(s):  
Sevitha Bhat ◽  
Kavya Ramamurthy ◽  
Shalini Shenoy ◽  
Aseem Rangnekar
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Predictive Value ◽  
High Sensitivity ◽  
Mortality And Morbidity ◽  
Indicator Tube ◽  
Promising Tool ◽  
Causes Of Mortality ◽  
Conventional Microscopy ◽  
Tb Diagnostics ◽  
Sensitivity Specificity

ABSTRACTObjectives: Mycobacterium tuberculosis (MTB) remains one of the most significant causes of mortality and morbidity in developing countriesespecially India. India has the highest burden of TB, with an estimated incidence figure of 2.1 million cases out of the 9 million cases of TB globally.Diagnosis of TB relies on conventional microscopy and culture with drawbacks related to sensitivity, specificity, turn around time (TAT). The aim ofthis study was to evaluate the performance of Xpert MTB/rifampicin (RIF) assay (GX) for MTB detection in pulmonary and extrapulmonary clinicalsamples.Methods: A total of 209 clinical specimens (182: pulmonary and 27: extrapulmonary) were processed using auramine smear, culture by mycobacteriagrowth indicator tube and GenXpert.Results: The sensitivity of GenXpert was 62.63% for pulmonary and 55% for extrapulmonary samples. The sensitivity and specificity of GX were100% for the smear positive cases. The sensitivity, specificity, positive predictive value, and negative predictive value of the GX for smear negativecases were 67.8%, 97.5%, 90.4%, and 89.6%, respectively. RIF resistance was detected in 3.8% the samples.Conclusion: GenXpert, with short TAT, high sensitivity, specificity and less technical expertise required is a promising tool in TB diagnostics for thefuture.Keywords: GenXpert, Tuberculosis diagnosis, Molecular method, Rifampicin resistance.

scholarly journals Evaluation of the COBAS AMPLICOR MTB test for the detection of Mycobacterium tuberculosis complex

2004 ◽  
Vol 10 (3) ◽  
pp. 329-335
Author(s):  
K. K. Abu Amero ◽  
M. A. Halablab
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Mycobacterium Tuberculosis Complex ◽  
Tuberculosis Complex ◽  
False Negatives ◽  
Predictive Values ◽  
Lowenstein Jensen ◽  
Polymerase Chain ◽  
Sensitivity Specificity ◽  
Culture Positive ◽  
Positive Results

Wevaluated the COBAS AMPLICOR polymerase chain reaction [PCR] based test for the detection of Mycobacterium tuberculosis complex in 866 respiratory and non-respiratory samples. Acid-fast staining and culture on Lowenstein-Jensen medium were also performed on all samples. Of the 866 samples tested, 87 [10.0%] were PCR-positive compared to 94 [10.9%] culture positive. There were no false positive results but 7 PCR-negative, culture-positive samples were, considered false negatives after reviewing medical records of patients. A PCR inhibitory rate of 2.0% [17/866] was observed in respiratory samples only. Sensitivity, specificity, and positive and negative predictive values for this test were 92.5%, 100%, 100% and 99.1% respectively. This test is a valuable diagnostic tool for today’s mycobacteriology laboratory

scholarly journals Comparative Evaluation between Detection of Mycobacterium Tuberculosis Complex in Samples of Extra Pulmonary Tuberculosis using Gene Xpert MTB/RIF Assay and Ziehl-Neelsen Staining in a Tertiary Care Hospital

2020 ◽  
Vol 5 (6) ◽  
pp. 1139-1141
Author(s):  
Om Prakash Bharati ◽  
Manoj Kumar ◽  
Ashok Kumar Sharma
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Pulmonary Tuberculosis ◽  
Predictive Value ◽  
Mycobacterium Tuberculosis Complex ◽  
Care Hospital ◽  
Tuberculosis Complex ◽  
Extra Pulmonary Tuberculosis ◽  
Two Samples ◽  
Extra Pulmonary ◽  
Sensitivity Specificity

Tuberculosis is a global problem and incidence of extra pulmonary tuberculosis is increasing day by day. Diagnosis of extra pulmonary tuberculosis is a little bit difficult than pulmonary tuberculosis.Aim and Objective: The aim of this study is to correlate between isolates of mycobacterium in GeneXpert and ZiehlNeelsen (ZN) staining. It also detects the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of GeneXpert assay and ZN staining.This prospective study was carried out in the Department of Microbiology, RIMS, Ranchi, Jharkhand. Seventy two samples from suspected patients of Extra pulmonary tuberculosis were taken. These samples were processed for test in GeneXpert assay, ZN staining and MGIT culture. Mycobacterium tuberculosis complex isolated from culture was taken as gold standard and compared with result of GeneXpert and ZN staining. Result: Out of 72 samples, detection rate of GeneXpert, MGIT and ZN staining were 27.77%, 26.38% and 18%. The sensitivity, specificity, PPV and NPV of ZN staining and GeneXpert were 63.15%, 98.11%, 92.3%, 88.13% and 94.73%, 96.22%, 90%, 98% respectively. GeneXpert is a rapid and easy method for extra pulmonary tuberculosis diagnosis. It not only detect the bacilli but also diagnose rifampicin drug resistance. This method prompts in diagnosis and treatment.

scholarly journals Cord Formation in BACTEC Medium Is a Reliable, Rapid Method for Presumptive Identification of Mycobacterium tuberculosis Complex

1998 ◽  
Vol 36 (9) ◽  
pp. 2769-2771 ◽  
Author(s):  
Yvette S. McCarter ◽  
Irene N. Ratkiewicz ◽  
Ann Robinson
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Positive Predictive Value ◽  
Negative Predictive Value ◽  
Rapid Method ◽  
Predictive Value ◽  
Mycobacterium Tuberculosis Complex ◽  
Tuberculosis Complex ◽  
Presumptive Identification ◽  
Sensitivity Specificity

Serpentine cord formation in BACTEC 12B medium was evaluated as a rapid method for the presumptive identification of M. tuberculosis complex. Kinyoun acid-fast stained smears were prepared from 666 positive BACTEC 12B bottles and examined for the presence or absence of serpentine cording. Cord formation had a sensitivity, specificity, positive predictive value, and negative predictive value of 89.2, 99.2, 98.5, and 94.2%, respectively. The evaluation of the presence of cord formation in BACTEC 12B medium is reliable and permits the rapid presumptive reporting of M. tuberculosis.

A comparative study of Conventional methods and GeneXpert Mycobacterium tuberculosis Rifampicin (MTB/RIF) assay for diagnosis of childhood pulmonary tuberculosis

2019 ◽  
Author(s):  
Allah Rakhia ◽  
Taj Muhammad Laghari ◽  
Muhammad Ayaz Mustufa ◽  
Yahya Noori ◽  
Rahila Bhutto ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Predictive Value ◽  
Diagnostic Tests ◽  
Rapid Test ◽  
Clinical History ◽  
Smear Microscopy ◽  
Indicator Tube ◽  
Mdr Tb ◽  
Lowenstein Jensen ◽  
Early Case

Abstract Background Diagnosis of childhood TB (tuberculosis) is challenging because its symptoms resemble other diseases, very few (less than five) mycobacteria are capable of causing the disease and children do not or rarely expectorate. These peculiar attributes make childhood TB different from adult TB but it is still not being dealt differently from adult TB .Despite evidences from national, international data and WHO recommendation for use of Gene expert/TB/RIF assay, decision to start the treatment is based mostly on Chest X ray, tuberculin skin test, history of contact and clinical sign and symptoms .Therefore, we planned this study to find best available choices of diagnostic tests for early case detection of childhood TB particularly MDR TB Methods: This comparative analytical study of 15 months was done at PHRC, SRCCH, NICH and Provincial TB Lab Ojha Institute of chest diseases Karachi. Our study population comprised of 143 probable cases of pulmonary TB below the age of 15 years. After taking written consent from parent/guardian, a Performa was filled with contact no, address, clinical history, scoring chart and diagnostic tests suggested by attending clinician. ZN staining for smear microscopy GeneXpert Mycobacterium tuberculosis Rifampicin (Xpert MTB/RIF) assay, Culture on Lowenstein–Jensen (L.J) media and Mycobacterium Growth Indicator Tube (MGIT) was done for every sample according to standard operating procedures of WHO and results were entered and analyzed on SPSS statistical package for social sciences. Results Out of 143 samples 7 (5%) were positive for MTB via Xpert MTB/RIF assay while 3(2.09) were positive through AFB microscopy, LJ culture and MGIT. When compared with gold standard blood culture sensitivity and negative predictive value of Xpert MTB/RIF were 100% and 97.14% while specificity and positive predictive value were 97.14% and 43% respectively. Conclusion Xpert MTB/RIF is a rapid test that can aid in timely diagnosis of peds TB, facilitating the timely treatment. However, specificity and PPV need to be taken into account. Key words: AFB microscopy, LJ and MGIT, Xpert MTB/RIF, Peds TB.

Determination some Immunological Aspects in Pulmonary Tuberculosis Patients in Qadisiyah Province

2018 ◽  
Vol 9 (2) ◽  
Author(s):  
Syoof Khowman Alramahy ◽  
Akram Hadi Hamza
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Pulmonary Tuberculosis ◽  
Statistical Difference ◽  
Positive Culture ◽  
Control Group ◽  
Tuberculosis Patients ◽  
Significant Difference ◽  
Lowenstein Jensen ◽  
The Mean ◽  
Igg Level

This study was carried out to study of some immunological aspects among the pulmonary Tuberculosis patients infected with causative agent, Mycobacterium tuberculosis. A Total of 200 sputum samples were collected from patients attending the consultant Clinic for Chest and Respiratory disease center, Diwaniya. Control group (No=15) also included. According to acid fast stain of sputum, the patients were classified as positive (No=91,45.5%) and negative (No=109,54.5, Lowenstein Jensen medium used for the cultivation of samples, on which 70% of sputum samples where positive culture for this microorganism. The grown microorganism were identified as M. tuberculosis, based on positive A.F.B, Niacin producers ,negative for catlase at 68c. The mean IgG level was l184.053±76.684 mg/100 ml in tuberculosis group compared with 1016.533 ± 44.882 mg/100ml in control group, rendering the statistical difference significant. For IgA and IgM levels, they were at mean of 315.880±38.552 mg/100 ml and 119.527±8.464 mg/100 ml in control group compared with 396.358±38.776 mg/100 ml and 134.207±11.696 mg/100 ml in patients group respectively with significant difference

Comparison of Papanicolaou Test With Visual Detection Tests in Screening for Cervical Cancer and Developing the Optimal Strategy for Low Resource Settings

2010 ◽  
Vol 20 (5) ◽  
pp. 862-868 ◽  
Author(s):  
Pakhee Aggarwal ◽  
Swaraj Batra ◽  
Gauri Gandhi ◽  
Vijay Zutshi
Keyword(s):  
Cervical Cancer ◽  
Predictive Value ◽  
Visual Inspection ◽  
Visual Detection ◽  
Alternative Methods ◽  
Papanicolaou Test ◽  
Low Resource Settings ◽  
Low Resource ◽  
The Mean ◽  
Sensitivity Specificity

Objectives:To compare the sensitivity, specificity, positive and negative predictive values, and accuracy of Papanicolaou test with visual inspection with acetic acid (VIA)/VIA using magnification devices (VIAM) and develop the best strategy for screening in low resource settings.Materials and Methods:This is a prospective cross-sectional study on 408 symptomatic multiparous women in the reproductive age group, sequentially using the Papanicolaou test, the VIA, and the VIAM for screening. Women with a positive screening test underwent guided biopsy and endocervical curettage. The site of biopsy was recorded. Histopathological findings were taken as the "gold" standard in comparing the methods.Results:The mean (SD) age was 32.3 (6.8) years (range, 15-49 years), whereas the mean (SD) parity was 2.9 (1.2) (range, 1-9). Abnormal cytological findings were detected in 2.9% patients, whereas the remaining smears were negative for any intraepithelial lesion or malignancy. A total of 113 cases were screened positive by one/all methods. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the Papanicolaou test, the VIA, and the VIAM were 24, 98, 42, 96, and 94%; 95, 78, 19, 99, and 79%; and 95, 78, 19, 99, and 79%, respectively, for high-grade lesions.Conclusions:The Papanicolaou test had low sensitivity but high specificity, whereas visual detection methods had a high sensitivity in addition to being cheaper. Alternative methods of screening such as VIA/VIAM can be a valuable alternative to the Papanicolaou test for cervical cancer screening in low resource settings. Visual inspection using magnification devices may be of benefit over VIA in doubtful cases.

scholarly journals Tuberculous Meningitis: The Microbiological Laboratory Diagnosis and Its Drug Sensitivity Patterns

2019 ◽  
Vol 3 (2) ◽  
pp. 35
Author(s):  
Titiek Sulistyowati ◽  
Deby Kusumaningrum ◽  
Eko Budi Koendhori ◽  
Ni Made Mertaniasih
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Tuberculous Meningitis ◽  
Drug Sensitivity ◽  
Mycobacterium Tuberculosis Complex ◽  
Laboratory Diagnosis ◽  
Clinical Microbiology Laboratory ◽  
Tuberculosis Complex ◽  
First Line ◽  
Sensitivity Pattern ◽  
Microbiological Laboratory

Background: Tuberculosis continues one of the major challenges to global health. Mycobacterium tuberculosis complex can affect any organ other than the lung parenchyma, include central nervous system. The mortality rate of tuberculous meningitis (TBM) are high worldwide with up to half of survivors suffering irreversible sequelae. Diagnosis of TBM is difficult due to paucibacillary, various clinical manifestation, and invasive procedure to appropriate specimens. Objective: The objectiveis to study the positivity rate of microbiological laboratory diagnosis and its drug sensitivity patterns of TBM patients in Dr. Soetomo Hospital Surabaya during October 2015 until September 2016. Methods: Specimens were cerebrospinal fluids. Identification and drug anti TB sensitivity test were done by BACTEC MGIT 960 system in Clinical Microbiology Laboratory Dr. Soetomo Hospital Surabaya. Result: Most patients with TBM were women (54.29%). Based on age groups, most dominant was adult population (65.71%). Proportion percentage of positive M. tuberculosis complex among 180 specimens were 19.44%. First line anti TB drug sensitivity pattern of 35 isolates were 1 monoresistant, 1 poly-resistant, no multiple drug resistant (MDR), and 33 pan-susceptible. Conclusion: Positivity rate of Mycobacterium tuberculosis complex laboratory diagnosis from TBM suspect patients were low. There was no MDR TB in this study, but mono-resistant and poly-resistant. Microbiological diagnosis was important to give information of active disease and drug sensitivity pattern. Resistance to first line anti TB drugs is alarming to properly manage TBM patients.

scholarly journals Multicenter Evaluation of the BACTEC MGIT 960 System for Recovery of Mycobacteria

1999 ◽  
Vol 37 (3) ◽  
pp. 748-752 ◽  
Author(s):  
Bruce A. Hanna ◽  
Adeleh Ebrahimzadeh ◽  
L. Bruce Elliott ◽  
Margie A. Morgan ◽  
Susan M. Novak ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Liquid Medium ◽  
Mycobacterium Avium ◽  
Culture Systems ◽  
Solid Media ◽  
Lowenstein Jensen ◽  
The Mean

We evaluated the BACTEC MGIT 960 system, which is a fully automated, noninvasive system for the growth and detection of mycobacteria with a capacity to incubate and continuously monitor 960 7-ml culture tubes. We studied 3,330 specimens, 2,210 respiratory and 1,120 nonrespiratory specimens, collected from 2,346 patients treated at six sites. Processed specimens were inoculated into the BACTEC MGIT 960 and BACTEC 460 TB systems, as well as onto Lowenstein-Jensen slants and Middlebrook 7H11/7H11 selective plates. From all culture systems, a total of 362 isolates of mycobacteria were recovered; these were recovered from 353 specimens collected from 247 patients. The greatest number of isolates of mycobacteria (289, or 80% of the 362 isolates) was recovered with the BACTEC MGIT 960, followed by the BACTEC 460 TB (271, or 75%) and solid media (250, or 69%). From all culture systems a total of 132 isolates of Mycobacterium tuberculosiscomplex were recovered. The greatest number of isolates of M. tuberculosis complex was recovered when liquid medium was combined with conventional solid media; the number recovered with BACTEC 460 TB plus solid media was 128 (97%), that recovered with BACTEC MGIT 960 plus solid media was 121 (92%), that recovered with BACTEC 460 TB was 119 (90%) and that recovered with all solid media combined was 105 (79%). The recovery with BACTEC MGIT 960 alone was 102 (77%). The mean times to detection (TTD) for M. tuberculosis complex were 14.4 days for BACTEC MGIT, 15.2 days for BACTEC 460 TB, and 24.1 days for solid media. The numbers of isolates of Mycobacterium avium complex (MAC) recovered were 172 (100%) for all systems, 147 (85%) for BACTEC MGIT 960, 123 (72%) for BACTEC 460 TB, and 106 (62%) for all solid media combined. The TTD for MAC in each system were 10.0 days for BACTEC MGIT 960, 10.4 days for BACTEC 460 TB, and 25.9 days for solid media. Breakthrough contamination rates (percentages of isolates) for each of the systems were 8.1% for BACTEC MGIT 960, 4.9% for BACTEC 460 TB, and 21.1% for all solid media combined.

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