Background: In Gabon, the epidemiology of tuberculosis has been considerably reshaped by the AIDS virus. It is in this context that the present study was conducted to assess the prevalence of pulmonary tuberculosis an...Background: In Gabon, the epidemiology of tuberculosis has been considerably reshaped by the AIDS virus. It is in this context that the present study was conducted to assess the prevalence of pulmonary tuberculosis and associated factors among patients at the Amissa Bongo Regional Hospital in Franceville, Gabon. Patients and Methods: This prospective, cross-sectional study was conducted in the biomedical analysis laboratory of the Amissa Bongo Regional University Hospital in Franceville from 19 June 2021 to 22 January 2022. After agreeing to take part in the study, participants were asked to fill in a questionnaire to collect their socio-demographic data and habits. Clinical signs were also observed. Sputum and gastric fluid samples were collected and examined using the Xpert MTB/RIF test and BAAR smear microscopy. Data were analysed using R software version 3.6.1. The results of the univariate and multivariate analyses were considered significant for p ≤ 0.05. Results: A total of 309 patients were included in this study, 50.81% (n = 157) men and 49.19% (n = 152) women. Of these, 98 had a positive diagnosis of pulmonary tuberculosis, giving an overall prevalence rate of 31.72%. There were 40 women or 40.82% (95% CI: [0.30 - 0.51]) and 58 men or 59.18% (95% CI: [0.48 - 0.69]). A univariate analysis of the prevalence of tuberculosis according to risk factors and clinical signs indicated a certain association between certain variables. However, an in-depth multivariate logistic regression analysis of this prevalence, according to the risk factors and clinical signs observed in the patients in the study, indicated that the age group 15 and 49 years (Adjusted OR = 47.77;95% CI: [4.4;519.7] p = 0.001*), fever (Adjusted OR = 4.83;95% CI: [1.16, 20.12] p = 0.031*), alcohol consumption (Adjusted OR = 12.2;95% CI: 12.2 [2.5;5.9] p = 0. 002*), smoking (Adjusted OR = 9.83;95% CI: [1.78;54.24] p = 0.037), HIV infection (Adjusted OR = 4.63;95% CI: [1.25;17.1] p = 0.022), cough (Adjusted OR = 4.31;95% CI: [1.21, 15.4] p = 0. 展开更多
Objective:To investigate the application of Ziehl-Neelsen(Z-N) and fluorescent microscopy in detection of acid fast bacilli(AFB).Methods:Duplicate smears were prepared from 260 sputum samples and stained with Z-N and ...Objective:To investigate the application of Ziehl-Neelsen(Z-N) and fluorescent microscopy in detection of acid fast bacilli(AFB).Methods:Duplicate smears were prepared from 260 sputum samples and stained with Z-N and fluorescent staining(FS) methods.The efficiency of both methods in primary diagnosis of tuberculosis were evaluated.Results:The smears were positive for AFB in 15(5.77%) samples by Z-N staining method and in 16(6.15%) samples by FS method.The sensitivity and specificity of Z-N staining method against FS method were 93.75% and 100%respectively.Conclusions:Though lesser cost-effective than Z-N,FS method is a more sensitive and better case finding tool in detection of AFB.展开更多
Background: Tuberculosis is a highly infectious disease and India has the highest burden with it. Diagnosis of tuberculosis in many countries is still dependent on microscopy. Although its sensitivity is low in compar...Background: Tuberculosis is a highly infectious disease and India has the highest burden with it. Diagnosis of tuberculosis in many countries is still dependent on microscopy. Although its sensitivity is low in comparison to culture and molecular methods, its sensitivity can still be improved by using fluorescence staining method and processing of samples by homogenization and concentration method. Material and methods: Samples were collected from all newly registered suspected cases of tuberculosis in tertiary care hospital from outward and indoor department during a period of one year. Smears were prepared for Ziehl Neelsen stain and fluorescence stain both before and after homogenization and concentration procedure by 4% NAOH-2.9% sodium citrate method and results of them were interpreted according to RNTCP criteria for grading of sputum samples. All the samples were cultured in liquid culture MGIT system (Mycobacterial Growth Indicator Tube) and results of microscopy were compared with liquid culture taken as gold standard. Data were analyzed by using SPSS software version 16. Result: 350 samples were collected during study period. Out of 350 samples, 48 samples were positive for M. tuberculosis by MGIT system. In comparison with MGIT system, sensitivity of Z N stain for detection of acid fast bacilli was 77% before decontamination procedure, which was increased up to 85.42% after decontamination and concentration process. Sensitivity of fluroscence stain was 85.42% before processing, which was increased up to 91.67% after processing of samples. Conclusion: Sensitivity of smear microscopy can be enhanced by use of fluroscence microscopy and concentration method.展开更多
Tuberculosis represents a main concern for public health worldwide. In poor countries, the most prevalent method for bacteriological confirmation re- mains Smear Sputum Microscopy (SSM). This study objective was to as...Tuberculosis represents a main concern for public health worldwide. In poor countries, the most prevalent method for bacteriological confirmation re- mains Smear Sputum Microscopy (SSM). This study objective was to assess clinical performances of Loop Mediated Isothermal Amplification for TB detection (Lamp-TB). Sputum of patients presenting symptoms consistent with tuberculosis were collected according to the National Tuberculosis Control Programme guidelines in Centre Antituberculeux de Yopougon. SSM after Ziehl-Neelsen staining and TB-Lamp were blindly performed with spot sputum specimen. Samples, transported at Institut Pasteur de Cote d’Ivoire were decontaminated according to N-acetyl-L-cystein (NALC) method. In Mycobacteria Growth Indicator Tube (MGIT), 500 μl of pellet were inoculated and incubated in MGIT 960 instrument. MPT64 antigen was detected on positive culture. Of 500 patients enrolled, 469 were included. Clinical isolates of M. tuberculosis Complex were detected for 157 (33.5%). Comparatively to culture, Sensitivity and Specificity of SSM were 86% (95% Confidence interval (CI): 81% - 91%) 96% (95%IC: 94% - 98%) respectively. TB-Lamp Sensitivity was 92% (95%CI: 88% - 96%), and Specificity 94% (95%CI: 91% - 97%). Positive Predictive Value of SSM and TB-Lamp was 91.8% and 88.8% respectively. Negative Predictive Value of TB-Lamp assay was 95.7% whereas this of SSM was 93.3%. Positive Likelihood Ratio was 15.3 for TB-Lamp and 21.5 for SSM 21.5 whereas negative Likelihood of TB-Lamp was lower than SSM. Active tuberculosis was detected in162/469 (34.5%) with TB-Lamp and 147 (31.3%) with SSM. TB-Lamp assay performances estimated from sputum samples may improve detection of active TB cases in routine.展开更多
This study was designed to evaluate the QBC ParaLensTM LED fluorescent microscope attachment and the QBC F.A.S.T.TM AFB staining system for the detection of Acid Fast Bacilli in pathological samples in Abidjan, Cote d...This study was designed to evaluate the QBC ParaLensTM LED fluorescent microscope attachment and the QBC F.A.S.T.TM AFB staining system for the detection of Acid Fast Bacilli in pathological samples in Abidjan, Cote d’Ivoire. A total of 50 patients were tested using direct smear specimens with both Ziehl-Neelsen (ZN) light microscopy and LED fluorescence microscopy with QBC F.A.S.T. AFB stain. The samples were also cultured and tested using an immunochromatograpic test for detection of antigen MPT 64 and the results were compared to direct examination. ZN light microscopy detected 20 positive cases and LED fluorescent microscopy with QBC F.A.S.T. AFB stain detected 21. The sensitivity and specificity of ZN light microscopy was determined to be 84.2% and 87.1% respectively. The sensitivity and specificity of LED fluorescent microscopy with QBC F.A.S.T. AFB stain was determined to be 94.7% and 90.3% respectively. Compared to ZN light microscopy, LED fluorescent microscopy with QBC F.A.S.T. AFB stain increased the sensitivity of direct examination without concentration by 10.5%.展开更多
Objective:To investigate granuloma associated mycobacteriosis in Pampus argenteus(P.argenteus)(silver pomfrets)and its seasonal prevalence in marine and coastal aquaculture systems of West Bengal,India.Methods:P.argen...Objective:To investigate granuloma associated mycobacteriosis in Pampus argenteus(P.argenteus)(silver pomfrets)and its seasonal prevalence in marine and coastal aquaculture systems of West Bengal,India.Methods:P.argenteus having granulomatous infection were sampled from coastal areas of East Midnapore District of West Bengal from January 2014 to December 2015,encompassing the various seasons.Tissue samples were collected for confirmation by biochemical studies and their prevalence and degree of infection and histopathology was conducted.Results:A total of 197 fishes having haemorrhage like infections in skin and viscera were confirmed for mycobacteria by biochemical analysis,with prevalence of 22.6%.Post-winter season showed higher prevalence(47.97%)followed by winter(35.25%),pre-winter(27.81%),summer(12.5%)and rainy season(2.57%)respectively.Histopathological assessment showed necrotic granuloma in skin,gills and some internal tissues.Ziehl-Neelsen staining of infected tissue samples showed the deposition of acid fast organisms causing swelling and haemorrhages in the tissues.Severity of infection was evaluated by mean cumulative granuloma score(7.89)score.Majority of the acid fast bacilli were recovered from skin,gills and other organs.Biochemical assessment of the acid fast rods confirmed the presence of Mycobacterium spp.Conclusions:The result suggests that the nontuberculous mycobacterial species are responsible for the granulomatous infection in P.argenteus.This infection seems to be influenced by environmental temperature,with the lower temperature favoring the pathogens.展开更多
Background： Direct ZN （Ziehl-Neelsen） sputum smear microscopy for diagnosis of TB （tuberculosis） has low sensitivity, especially in TB/HIV co-infected patients. Sputum concentration by bleach （NaOCI） with sedim...Background： Direct ZN （Ziehl-Neelsen） sputum smear microscopy for diagnosis of TB （tuberculosis） has low sensitivity, especially in TB/HIV co-infected patients. Sputum concentration by bleach （NaOCI） with sedimentation has been used to increase the sensitivity of sputum smear microscopy in many settings but with varying results. Objective： To determine whether bleach plus centrifugation significantly improves the detection of AFB （acid-fast bacilli） in ZN smear-negative sputum specimens. Methods： Three hundred and seventy sputum specimens were collected from new TB suspects attending a Nairobi referral district hospital and processed for direct microscopy using ZN technique and culture on Lowenstein Jensen Media. All smear-negative specimens were treated with 3.5% bleach and left to stand for 30 min before centrifugation. The bleach treated smears were processed and examined using ZN technique. Results： Of the 370 specimens, 200 （54%） were positive culture. The number of sputum samples that were smear-positive by direct ZN was 138 （37.2%）, with a sensitivity of 66%. After treatment of direct ZN smear-negative specimens with 3.5% bleach and centrifugation, the total number of AFB smear-positive samples increased to 171 with an increase in sensitivity of 66% to 81.1% （15.1%）. Conclusion： In this study, bleach with centrifugation significantly increased the yield of sputum smear microscopy. Further evaluation of these techniques in routine programmes is required especially in settings where the burden of TB/HIV is high.展开更多
文摘Background: In Gabon, the epidemiology of tuberculosis has been considerably reshaped by the AIDS virus. It is in this context that the present study was conducted to assess the prevalence of pulmonary tuberculosis and associated factors among patients at the Amissa Bongo Regional Hospital in Franceville, Gabon. Patients and Methods: This prospective, cross-sectional study was conducted in the biomedical analysis laboratory of the Amissa Bongo Regional University Hospital in Franceville from 19 June 2021 to 22 January 2022. After agreeing to take part in the study, participants were asked to fill in a questionnaire to collect their socio-demographic data and habits. Clinical signs were also observed. Sputum and gastric fluid samples were collected and examined using the Xpert MTB/RIF test and BAAR smear microscopy. Data were analysed using R software version 3.6.1. The results of the univariate and multivariate analyses were considered significant for p ≤ 0.05. Results: A total of 309 patients were included in this study, 50.81% (n = 157) men and 49.19% (n = 152) women. Of these, 98 had a positive diagnosis of pulmonary tuberculosis, giving an overall prevalence rate of 31.72%. There were 40 women or 40.82% (95% CI: [0.30 - 0.51]) and 58 men or 59.18% (95% CI: [0.48 - 0.69]). A univariate analysis of the prevalence of tuberculosis according to risk factors and clinical signs indicated a certain association between certain variables. However, an in-depth multivariate logistic regression analysis of this prevalence, according to the risk factors and clinical signs observed in the patients in the study, indicated that the age group 15 and 49 years (Adjusted OR = 47.77;95% CI: [4.4;519.7] p = 0.001*), fever (Adjusted OR = 4.83;95% CI: [1.16, 20.12] p = 0.031*), alcohol consumption (Adjusted OR = 12.2;95% CI: 12.2 [2.5;5.9] p = 0. 002*), smoking (Adjusted OR = 9.83;95% CI: [1.78;54.24] p = 0.037), HIV infection (Adjusted OR = 4.63;95% CI: [1.25;17.1] p = 0.022), cough (Adjusted OR = 4.31;95% CI: [1.21, 15.4] p = 0.
文摘Objective:To investigate the application of Ziehl-Neelsen(Z-N) and fluorescent microscopy in detection of acid fast bacilli(AFB).Methods:Duplicate smears were prepared from 260 sputum samples and stained with Z-N and fluorescent staining(FS) methods.The efficiency of both methods in primary diagnosis of tuberculosis were evaluated.Results:The smears were positive for AFB in 15(5.77%) samples by Z-N staining method and in 16(6.15%) samples by FS method.The sensitivity and specificity of Z-N staining method against FS method were 93.75% and 100%respectively.Conclusions:Though lesser cost-effective than Z-N,FS method is a more sensitive and better case finding tool in detection of AFB.
文摘Background: Tuberculosis is a highly infectious disease and India has the highest burden with it. Diagnosis of tuberculosis in many countries is still dependent on microscopy. Although its sensitivity is low in comparison to culture and molecular methods, its sensitivity can still be improved by using fluorescence staining method and processing of samples by homogenization and concentration method. Material and methods: Samples were collected from all newly registered suspected cases of tuberculosis in tertiary care hospital from outward and indoor department during a period of one year. Smears were prepared for Ziehl Neelsen stain and fluorescence stain both before and after homogenization and concentration procedure by 4% NAOH-2.9% sodium citrate method and results of them were interpreted according to RNTCP criteria for grading of sputum samples. All the samples were cultured in liquid culture MGIT system (Mycobacterial Growth Indicator Tube) and results of microscopy were compared with liquid culture taken as gold standard. Data were analyzed by using SPSS software version 16. Result: 350 samples were collected during study period. Out of 350 samples, 48 samples were positive for M. tuberculosis by MGIT system. In comparison with MGIT system, sensitivity of Z N stain for detection of acid fast bacilli was 77% before decontamination procedure, which was increased up to 85.42% after decontamination and concentration process. Sensitivity of fluroscence stain was 85.42% before processing, which was increased up to 91.67% after processing of samples. Conclusion: Sensitivity of smear microscopy can be enhanced by use of fluroscence microscopy and concentration method.
文摘Tuberculosis represents a main concern for public health worldwide. In poor countries, the most prevalent method for bacteriological confirmation re- mains Smear Sputum Microscopy (SSM). This study objective was to assess clinical performances of Loop Mediated Isothermal Amplification for TB detection (Lamp-TB). Sputum of patients presenting symptoms consistent with tuberculosis were collected according to the National Tuberculosis Control Programme guidelines in Centre Antituberculeux de Yopougon. SSM after Ziehl-Neelsen staining and TB-Lamp were blindly performed with spot sputum specimen. Samples, transported at Institut Pasteur de Cote d’Ivoire were decontaminated according to N-acetyl-L-cystein (NALC) method. In Mycobacteria Growth Indicator Tube (MGIT), 500 μl of pellet were inoculated and incubated in MGIT 960 instrument. MPT64 antigen was detected on positive culture. Of 500 patients enrolled, 469 were included. Clinical isolates of M. tuberculosis Complex were detected for 157 (33.5%). Comparatively to culture, Sensitivity and Specificity of SSM were 86% (95% Confidence interval (CI): 81% - 91%) 96% (95%IC: 94% - 98%) respectively. TB-Lamp Sensitivity was 92% (95%CI: 88% - 96%), and Specificity 94% (95%CI: 91% - 97%). Positive Predictive Value of SSM and TB-Lamp was 91.8% and 88.8% respectively. Negative Predictive Value of TB-Lamp assay was 95.7% whereas this of SSM was 93.3%. Positive Likelihood Ratio was 15.3 for TB-Lamp and 21.5 for SSM 21.5 whereas negative Likelihood of TB-Lamp was lower than SSM. Active tuberculosis was detected in162/469 (34.5%) with TB-Lamp and 147 (31.3%) with SSM. TB-Lamp assay performances estimated from sputum samples may improve detection of active TB cases in routine.
文摘This study was designed to evaluate the QBC ParaLensTM LED fluorescent microscope attachment and the QBC F.A.S.T.TM AFB staining system for the detection of Acid Fast Bacilli in pathological samples in Abidjan, Cote d’Ivoire. A total of 50 patients were tested using direct smear specimens with both Ziehl-Neelsen (ZN) light microscopy and LED fluorescence microscopy with QBC F.A.S.T. AFB stain. The samples were also cultured and tested using an immunochromatograpic test for detection of antigen MPT 64 and the results were compared to direct examination. ZN light microscopy detected 20 positive cases and LED fluorescent microscopy with QBC F.A.S.T. AFB stain detected 21. The sensitivity and specificity of ZN light microscopy was determined to be 84.2% and 87.1% respectively. The sensitivity and specificity of LED fluorescent microscopy with QBC F.A.S.T. AFB stain was determined to be 94.7% and 90.3% respectively. Compared to ZN light microscopy, LED fluorescent microscopy with QBC F.A.S.T. AFB stain increased the sensitivity of direct examination without concentration by 10.5%.
文摘Objective:To investigate granuloma associated mycobacteriosis in Pampus argenteus(P.argenteus)(silver pomfrets)and its seasonal prevalence in marine and coastal aquaculture systems of West Bengal,India.Methods:P.argenteus having granulomatous infection were sampled from coastal areas of East Midnapore District of West Bengal from January 2014 to December 2015,encompassing the various seasons.Tissue samples were collected for confirmation by biochemical studies and their prevalence and degree of infection and histopathology was conducted.Results:A total of 197 fishes having haemorrhage like infections in skin and viscera were confirmed for mycobacteria by biochemical analysis,with prevalence of 22.6%.Post-winter season showed higher prevalence(47.97%)followed by winter(35.25%),pre-winter(27.81%),summer(12.5%)and rainy season(2.57%)respectively.Histopathological assessment showed necrotic granuloma in skin,gills and some internal tissues.Ziehl-Neelsen staining of infected tissue samples showed the deposition of acid fast organisms causing swelling and haemorrhages in the tissues.Severity of infection was evaluated by mean cumulative granuloma score(7.89)score.Majority of the acid fast bacilli were recovered from skin,gills and other organs.Biochemical assessment of the acid fast rods confirmed the presence of Mycobacterium spp.Conclusions:The result suggests that the nontuberculous mycobacterial species are responsible for the granulomatous infection in P.argenteus.This infection seems to be influenced by environmental temperature,with the lower temperature favoring the pathogens.
文摘Background： Direct ZN （Ziehl-Neelsen） sputum smear microscopy for diagnosis of TB （tuberculosis） has low sensitivity, especially in TB/HIV co-infected patients. Sputum concentration by bleach （NaOCI） with sedimentation has been used to increase the sensitivity of sputum smear microscopy in many settings but with varying results. Objective： To determine whether bleach plus centrifugation significantly improves the detection of AFB （acid-fast bacilli） in ZN smear-negative sputum specimens. Methods： Three hundred and seventy sputum specimens were collected from new TB suspects attending a Nairobi referral district hospital and processed for direct microscopy using ZN technique and culture on Lowenstein Jensen Media. All smear-negative specimens were treated with 3.5% bleach and left to stand for 30 min before centrifugation. The bleach treated smears were processed and examined using ZN technique. Results： Of the 370 specimens, 200 （54%） were positive culture. The number of sputum samples that were smear-positive by direct ZN was 138 （37.2%）, with a sensitivity of 66%. After treatment of direct ZN smear-negative specimens with 3.5% bleach and centrifugation, the total number of AFB smear-positive samples increased to 171 with an increase in sensitivity of 66% to 81.1% （15.1%）. Conclusion： In this study, bleach with centrifugation significantly increased the yield of sputum smear microscopy. Further evaluation of these techniques in routine programmes is required especially in settings where the burden of TB/HIV is high.
