scholarly journals Performance of LED Fluorescence Microscopy for the Diagnosis of Pulmonary Tuberculosis in HIV Positive Individuals in Addis Ababa, Ethiopia

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Konjit Getachew ◽  
Tamrat Abebe ◽  
Abebaw Kebede ◽  
Adane Mihret ◽  
Getachew Melkamu

Background. Despite its lower sensitivity, smear microscopy remains the main diagnostic method for pulmonary tuberculosis (PTB) in resource-limited countries as TB culturing methods like LJ (Lowenstein-Jensen) are expensive to use as a routine base. This study aimed to evaluate the performance of LED-FM for the diagnosis of PTB in HIV positive individuals.Methods. Cross-sectional study was conducted in Zewditu Memorial Hospital and Teklehaimanot Health Center HIV/ART clinics in Addis Ababa, Ethiopia. Each sample was stained with ZN and Auramine O staining and examined with bright-field microscope and LED-FM microscope, respectively. LJ culture was used as a reference.Results. Out of 178 study participants, twenty-four (13.5%) patients were confirmed as positive for MTB with LJ culture. The yield of ZN microscopy and LED-FM in direct and concentrated sample was 3.9%, 8.4%, 6.2%, and 8.4%, respectively. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of direct ZN microscopy were 29.2%, 100%, 100%, and 90.1%, respectively, and of LED-FM microscopy in direct sputum sample were 62.5%, 100%, 100%, and 94.5%, respectively.Conclusion. LED-FM has better sensitivity for the diagnosis of PTB in HIV positive individuals as compared to conventional ZN microscopy. LED-FM can be used as an alternative to conventional ZN microscopy.

2018 ◽  
Vol 12 (1) ◽  
pp. 390-396
Author(s):  
Boja D. Taddese ◽  
Daniel M. Desalegn ◽  
Abay S. Misganaw ◽  
Kumera T. Kitila ◽  
Tinsae Kidanemariam Hailu ◽  
...  

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.


2017 ◽  
Vol 13 (1) ◽  
pp. 16-22
Author(s):  
Ashok Thapa ◽  
P Gurung ◽  
G R Ghimire

Introduction: Tuberculosis (TB) is one of the most deadly and common major infectious diseases in developing countries. Rapid and accurate diagnosis of tuberculosis is indispensable to adequately manage the disease and control its transmission. The objective of this study was to evaluate Gene Xpert MTB/RIF Assay for detection of M. tuberculosis in sputum of patients suspected of pulmonary tuberculosis and its comparison with traditional conventional methods.Methodology: A total of 138 patients sputum samples were collected and processed. Gene Xpert MTB/ RIF Assay, culture method and smear microscopy were performed under standard guideline inside biosafety cabinet class II. Data were reported, structured and analyzed using SPSS version 16.00. Study was carried out from June to November 2014.Results: Assay detected M. tuberculosis in 37 (26.81%) samples out of total 138. Of these 37, 10 and 3 were resistance and indeterminate to rifampicin respectively. Culture, Ziehl-Neelsen staining and Auramine staining were positive in 43 (31.16%), 18 (13.04%) and 24 (17.39%) samples respectively. Sensitivity, specificity, Positive predictive value and Negative predictive value of Assay were 76.74%, 95.79%, 89.19% and 90.09% respectively with reference to gold standard culture method.Conclusions: Assay was found rapid in direct detec tion of Mycobacterium tuberculosis in sputum sample and was also found more sensitive than both Ziehl-Neelsen staining and Auramine staining and especially showed good promise in diagnosis of smear negative specimens.SAARC J TUBER LUNG DIS HIV/AIDS, 2016; XIII(1), page: 16-22


2020 ◽  
Vol 9 (3) ◽  
pp. 190-194
Author(s):  
Naureen Saeed ◽  
Fatima-tuz-zuhra ◽  
Nadeem Ikram ◽  
Farhana Shaukat ◽  
Fareeha Sardar

Background: Pakistan faces an immense burden of pulmonary tuberculosis (TB) due to large number of cases and limited resources. Despite the recent advancement in the diagnostic techniques for pulmonary TB, smear microscopy is still a useful technique for the diagnosis of this disease. This study was conducted in order to compare the diagnostic value of Auramine stain with the conventional Ziehl-Neelsen (ZN) stain on the sputum smear for the diagnosis of pulmonary TB, keeping GeneXpert MTB/RIF as the gold standard. Method: This cross-sectional study was conducted on 356 suspected patients of pulmonary TB referred to the Pathology laboratory from TB ward and OPD of District Head Quarter (DHQ) teaching hospital Rawalpindi, Pakistan. Sputum specimen were collected and two smears were prepared from each sputum sample on which Auramine phenol and Ziehl-Neelsen staining were carried out as per WHO recommendations. All these samples were further tested using Gene Xpert MTB/RIF technique. The sensitivity, specificity, Positive predictive value (PPV) and Negative predictive values (NPV) of ZN and Auramine stain were calculated and compared with GeneXpert MTB/RIF technique. Results: Out of the total 356 samples, 64(18%) were positive and 291(82%) were negative by GeneXpert which was taken as the gold standard. On comparison with GeneXpert, percentage of true positive was greater in case of Auramine than ZN stained samples (16.29% versus 12.92%), while the percentage of false positive was same for both staining techniques (0.28%). There were lesser false negative cases observed in samples stained by Auramine as compared to the ones stained by ZN (1.68% versus 5.05%). The sensitivity, specificity, positive predictive value and negative predictive values were 97.87%, 94.17%, 71.88 and 99.66%, respectively for the ZN staining and 98.31%, 97.98%, 90.63% and 99.66% respectively, for the Auramine phenol staining. Conclusion: Smear microscopy using Auramine phenol stain is a useful technique for the diagnosis of pulmonary TB. The Auramine phenol staining with fluorescent microscopy is found to be superior to ZN staining because of higher sensitivity and specificity. Keywords: Auramine phenol, Fluorescence microscopy, GeneXpert, Mycobacterium tuberculosis, Ziehl-Neelsen


2016 ◽  
Vol 4 (1) ◽  
pp. 26-32
Author(s):  
Roshan Kurmi ◽  
Ramanuj Rauniyar ◽  
Krishna Das Manandhar ◽  
Birendra Prasad Gupta

Tuberculosis diagnosis and monitoring rely in Sputum microscopy of National Tuberculosis Programme, Nepal because of its low cost and easier to perform. Direct sputum microscopy is popular worldwide. Currently, there are 533 microscopy centres catering for sputum microscopy examination throughout the country. Most of the microscopy centres are established within government jurisdiction and remaining are established as non-governmental organization as well as private sectors.A cross-sectional study was conducted from July 2013 to January 2015. A total of 2091 patients were enrolled in the study who were attending the DOTS Centre in Parsa District of Public Health Office, Nepal. Smears stained with ZN stain methods were examined microscopically followed by the GeneXpert MTB/RIF assay.Out of 2091 suspected pulmonary TB patients enrolled for sputum microscopy and GeneXpert MTB/RIF for the confirmation of TB, the 1301(62.21%) were male and 790 (37.78%) were female. The maximum TB cases were from Parsa district (555, 26.5%). The comparative study of different diagnostic tools reveals the sensitivity of MTB/RIF was 95.50% (91.87, 97.82) and significantly higher than smear microscopy performed on the same fluid, which had a sensitivity of 61.97% (55.41, 68.21). Five of 127 smear-negative cases had MTB/RIF-positive un-centrifuged sputum, resulting in a specificity of 81.23% (75.95, 85.78), which was similar to smear microscopy 98.29 % (97.34, 98.97; p=0.121). The positive predictive value (PPV) and negative predictive value (NPV) of MTB/RIF were 96.85% (93.61, 98.72) and 94.95 % (93.52, 96.14), respectively. HIV co-infection did not impact sensitivity, specificity or liquid culture time to positivity (TTP). When MTB/RIF accuracy was evaluated using composite reference standard culture positivity from sputum, the sensitivity and specificity were similar to those obtained in the primary analysis using either definite TB versus possible and non-TB combined; definite and possible TB combined versus non-TB.


2019 ◽  
Author(s):  
Aynye Negesse ◽  
Mulugeta Belay ◽  
Girmay Medhin ◽  
Sosina Ayalew ◽  
Adane Mihret ◽  
...  

AbstractBackgroundThe current practice in Ethiopia to diagnose tuberculosis is screening patients with cough for at least two weeks. A health facility based study was conducted to estimate the prevalence of smear and culture positive pulmonary TB among patients presenting with cough ≥2 weeks and <2 weeks in Addis Ababa, Ethiopia.MethodsA cross-sectional study design was used to recruit patients with cough of any duration from four selected health centers in Addis Ababa, between August and December 2016. Sputum samples were collected from patients reporting productive cough of any duration and screened for Pulmonary Tuberculosis (PTB) using smear microscopy and culture methods. Mycobacterium tuberculosis isolates obtained from culture positive samples were characterized using RD9 deletion typing.ResultsMajority (39.7%) of the 725 study participants was in the age range of 20-30 years, and 5.0% were smear positive using smear microscopy. The prevalence of smear positive PTB among patients presented with cough duration of ≥2 weeks was significantly higher compared to those patients presented with cough duration of <2 weeks (10.9% versus 0.7%; χ2=38.98; p=0.001). Using culture method, a total of 86 (11.9%) participants were positive for mycobacteria, and the prevalence (14.6%) of PTB among patients presented with cough duration of ≥2 weeks was not significantly higher compared to prevalence (9.9%) in those patients presented with cough duration of <2 weeks (χ2=3.63; p=0.057). Molecular characterization of 86 culture positive mycobacterial isolates showed that 41 were infected with Mtb; 19(46.3%) from those who had cough duration of <2 weeks and 22(53.7%) from those who had cough duration of ≥2 weeks.ConclusionScreening of PTB using smear microscopy alone and cough duration of at least two weeks would negatively affect early diagnosis and treatment initiation in a considerable number of PTB patients who reports cough duration of <2 weeks with the potential of contributing to the spread of TB. Therefore, screening of patients with cough of any duration using both smear microscopy and culture methods is likely to contribute to the success of any effort towards the control of TB.


2014 ◽  
Vol 39 (2) ◽  
pp. 80-85
Author(s):  
MS Showkat ◽  
S Nabi ◽  
L Khondker ◽  
B Bhowmik ◽  
SN Tushar ◽  
...  

Transvagival sonography is superior to transabdominal sonography in most cases of pelvic pathology. Objective of this study is to evaluate the clinical usefulness of transvaginal ultrasonography (TVS) in pre, peri and post menopausal women suspected to have endometrial carcinoma. This cross sectional study was done with 40 patients who are clinically suspected having thickened endometrium. The study was carried out January 2007 to November 2008 for a period of two years. The patients having endometrial carcinoma diagnosed by TVS was correlated with histopathological diagnosis following collection of the report from the respective cases. Of total 40 cases, 2(5.0%) cases were endometrial carcinoma and 38(95.0%) were negative for endometrial carcinoma respectively in TVS findings. On the other hand 3(7.5%) cases were endometrial carcinoma and 37 (92.5%) cases were negative for endometrial carcinoma in histopathological findings. The validity of TVS in diagnosis of endometrial carcinoma were studied by calculating sensitivity, specificity, accuracy, positive predictive value and negative predictive value, which were 67 percent, 100 percent, 98 percent, 100 percent and 97 percent respectively. As the TVS findings of the present study correlated well with the histopathology findings and the validity test values were higher than observed by others, it can be concluded that TVS is sensitive and accurate modality in the evaluation of endometrial carcinoma. DOI: http://dx.doi.org/10.3329/bmrcb.v39i2.19647 Bangladesh Med Res Counc Bull 2013; 39: 80-85


2012 ◽  
Vol 20 (01) ◽  
pp. 132-138
Author(s):  
MUHAMMAD ATIF ◽  
MUHAMMAD ABDULLAH ◽  
MUHAMMAD JAVAD YOUSAF ◽  
Khalid Buland

Objective: To compare the accuracy of Upper lip bite test with modified Mallampati classification for predicting the difficultlaryngoscopic intubation. Study Design: Cross sectional Study. Place and duration of study: The study was carried out at Department ofAnaesthesiology, Intensive Care and Pain management, Combined Military hospital, Rawalpindi from September 2008 to August 2009.Patients and Methods: Four hundred patients undergoing elective surgery meeting the inclusion/exclusion criteria were enrolled afterwritten informed consent. The airways of the patients were evaluated by using the modified Mallampati classification (MMP) and theUpper lip bite test (ULBT). MMP class 3 or 4 and ULBT class 3 were considered as indicators of difficult intubation. The laryngeal view wasgraded by Cormack and Lehane classification (Gold standard). Grade 1 or 2 was considered to represent easy intubation and grade 3 or 4to represent difficult intubation. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy werecalculated for both the tests separately by using the 2×2 table. Results: ULBT had a higher accuracy of 94%, specificity of 99.2% andpositive predictive value 70% compared to MMP accuracy of 82.7%, specificity of 84.4% and positive predictive value of 22.7%.Conclusions: The diagnostic accuracy of the Upper lip bite test was more than the modified Mallampati classification. We suggest that itbe compared with the other prevailing tests as well which are often used to assess difficult intubations.


2020 ◽  
Author(s):  
Letebrhan Weldemhret

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.


2019 ◽  
Vol 6 ◽  
pp. 127-132
Author(s):  
Sanam Thapa Magar ◽  
Gokarna Ghimire ◽  
Pradeep Kumar Shah

Objectives: The objective of this study was to evaluate Gene Xpert MTB/RIF Assay and anid fast staining (AFB) for rapid detection of Mycobacterium tuberculosis in specimen of patients suspected of pulmonary tuberculosis (PTB) and extra pulmonary tuberculosis (EPTB). Methods: A comparative cross-sectional study of 400 samples (PTB-365 and EPTB-35) of patients visiting National Tuberculosis Centre (NTC) was conducted from July 2018 to December 2018. Gene Xpert MTB/ RIF Assay, smear microscopy were performed under standard guideline inside biosafety cabinet class II. The result obtained from both the tests were analyzed using SPSS 20.0 software and Excel 2019. Results: Of the total samples, 18% (72/400) and 39% (156/400) were positive by AFB smear microscopy and Xpert MTB/RIF assay respectively. Prevalence of MTB positive was highest in the age group 35-44 years, 33 cases (17.74%) were detected in total, with a male to female ratio of 2.3:1. Pleural fluid, pus, and CSF fluid also yielded positive results with the Gene Xpert MTB/RIF assay accounting 1.28%, 0.64% and 1.28% of MTB positive case respectively. Rifampicin resistance was observed in 1.28% of the cases. Conclusion: The key findings of this study suggest that Gene Xpert test should be implemented as primary diagnostic test for PTB and EPTB.


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