Segmentation of touching mycobacterium tuberculosis from Ziehl-Neelsen stained sputum smear images

2015 ◽  
Author(s):  
Chao Xu ◽  
Dongxiang Zhou ◽  
Yunhui Liu
2021 ◽  
Vol 10 (15) ◽  
pp. 3249
Author(s):  
Annelies W. Mesman ◽  
Seung-Hun Baek ◽  
Chuan-Chin Huang ◽  
Young-Mi Kim ◽  
Sang-Nae Cho ◽  
...  

An estimated 15–20% of patients who are treated for pulmonary tuberculosis (TB) are culture-negative at the time of diagnosis. Recent work has focused on the existence of differentially detectable Mycobacterium tuberculosis (Mtb) bacilli that do not grow under routine solid culture conditions without the addition of supplementary stimuli. We identified a cohort of TB patients in Lima, Peru, in whom acid-fast bacilli could be detected by sputum smear microscopy, but from whom Mtb could not be grown in standard solid culture media. When we attempted to re-grow Mtb from the frozen sputum samples of these patients, we found that 10 out of 15 could be grown in a glycerol-poor/lipid-rich medium. These fell into the following two groups: a subset that could be regrown in glycerol after “lipid-resuscitation”, and a group that displayed a heritable glycerol-sensitive phenotype that were unable to grow in the presence of this carbon source. Notably, all of the glycerol-sensitive strains were found to be multidrug resistant. Although whole-genome sequencing of the lipid-resuscitated strains identified 20 unique mutations compared to closely related strains, no single genetic lesion could be associated with this phenotype. In summary, we found that lipid-based media effectively fostered the growth of Mtb from a series of sputum smear-positive samples that were not culturable in glycerol-based Lowenstein–Jensen or 7H9 media, which is consistent with Mtb’s known preference for non-glycolytic sources during infection. Analysis of the recovered strains demonstrated that both genetic and non-genetic mechanisms contribute to the observed differential capturability, and suggested that this phenotype may be associated with drug resistance.


Author(s):  
Sevket Ozkaya ◽  
Salih Bilgin ◽  
Serhat Findik ◽  
Hayriye Çete Kök ◽  
Canan Yuksel ◽  
...  

Background: Endobronchial tuberculosis (EBTB) is defined as a tuberculous infection of the tracheobronchial tree with microbial and histopathological evidence, with or without parenchymal involvement. Bronchoscopic appearances of EBTB have been divided into seven subtypes: actively caseating, edematous-hyperemic, fibrostenotic, tumorous, granular, ulcerative, and nonspecific bronchitic. However, information for establishing a definite microbiological diagnosis in each of these categories is lacking. We aimed to present bronchoscopic appearances and percentages for the EBTB subtypes and to compare bronchoscopic appearances with microbiological positivity in bronchial lavage fluid. Methods: From 2003 to 2009, 23 biopsy-proven EBTB patients were enrolled in the study. Diagnosis of EBTB was histopathologically confirmed in all patients. Results: The commonest subtype was the edematous-hyperemic type (34.7%); other subtypes in order of occurrence were: tumorous (21.7%), granular (17.3%), actively caseating (17.3%), fibrostenotic (4.3%), and nonspecific bronchitic (4.3%). Although all patients were sputum-smear-negative for acid-fast bacilli (AFB), 26% of patients were smear-positive for AFB in the bronchial lavage fluid. The bronchial lavage fluid grew Mycobacterium tuberculosis in 39.1% of all patients. The bronchial lavage smear positivity for AFB in the bronchial lavage fluid was 75%, 25%, 20%, 12.5%, 0%, and 0% for the granular, actively caseating, tumorous, edematous-hyperemic, fibrostenotic, and nonspecific bronchitic subtypes of EBTB, respectively. Culture positivity for Mycobacterium tuberculosis in bronchial lavage fluid was 75%, 50%, 40%, 25%, 0%, and 0%, respectively. Conclusion: The commonest subtype of EBTB was the edematous-hyperemic subtype. The granular type had the highest smear positivity and culture positivity for Mycobacterium tuberculosis in bronchial lavage fluid. Bronchoscopy should be performed in all patients suspected to have EBTB.


2018 ◽  
Vol 146 (12) ◽  
pp. 1503-1510 ◽  
Author(s):  
P. Fernandes ◽  
Y. Ma ◽  
M. Gaeddert ◽  
T. Tsacogianis ◽  
P. Marques-Rodrigues ◽  
...  

AbstractGlobally, the prevalence of tuberculosis (TB) disease is higher in males. This study examined the effect of sex and age onMycobacterium tuberculosis(Mtb) infection. Demographic and exposure data were collected on household contacts of sputum smear-positive pulmonary TB patients in Brazil. Contacts with tuberculin skin test induration ⩾10 mm at baseline or 12 weeks were considered Mtb infected. The study enrolled 917 household contacts from 160 households; 508 (55.4%) were female, median age was 21.0 years (range 0.30–87.0) and 609 (66.4%) had Mtb infection. The proportion infected increased with age from 63.3% in girls <5 years to 75.4% in women ⩾40 years and from 44.9% in boys <5 years to 73.6% in men ⩾40 years. Multivariable modelling showed the odds of infection increased between age 5 and 14 years among female contacts (OR 1.5 per 5-year age increase; 95% CI 1.1–2.2;P= 0.02) and between ages 0–4 and 15–39 years among male contacts (OR 2.7, 95% CI 0.83–8.9 and 1.1, 95% CI 0.99–1.3 per 5-year age increase;P= 0.10, 0.07, respectively). The study suggests that the age at which Mtb infection increases most is different in females compared with males. Studies are needed to explore whether these findings are due to differences in host susceptibility, exposure outside the household or other factors.


2011 ◽  
Vol 90-93 ◽  
pp. 2460-2465 ◽  
Author(s):  
Md Rajuna Bin Ahmad Shakri ◽  
Rozana Binti Zakaria ◽  
Badrul Hisham Bin Abd Samad

Healthy indoor air environment quality is needed for healthy building hospital. Mycobacterium tuberculosis (MTB) is a microbial infectious agent which causes tuberculosis (TB) disease in human. Hence, health care workers (HCWs) are belonged to a highly potential risk group to be infected by MTB. This research aims to investigate the source and factor(s) of TB transmission in sustainable indoor air environment at the Hospital Sultanah Aminah Johor Bahru (HSAJB), Malaysia. The view taken in this paper is that the transmission dynamic of MTB from an active pulmonary TB (PTB) patient to another person via indoor air environment in the health care setting is generated as a result of an interaction between architect, building planner and owner, design and facility engineer, construction engineer, occupational health and safety professionals, hospital and HCWs, epidemiologist and public health officer. The findings were obtained by combining questionnaire and interview approaches using five ordinal measures of agreement using Likert Scale measurement. Analysis of qualitative data found that the source of MTB transmission was coming from active PTB patients especially those with sputum smear positive (SS+). The studied ambient parameters and factors affecting indoor air environment sustainability were thermal comfort, humidity, air pressure, temperature, duration exposure, area and volume, direction of air flow, lighting, air circulation exchange and MTB density in the air.


2006 ◽  
Vol 13 (6) ◽  
pp. 702-703 ◽  
Author(s):  
Eric Kassa-Kelembho ◽  
Edith Kassa ◽  
Germain Zandanga ◽  
Yves-Brillant Service ◽  
Albert Ignaleamoko ◽  
...  

ABSTRACT We assessed the performance of a serological test for tuberculosis (SDHO Laboratories Inc., Canada) in our setting. Among 68 of 99 suspected pulmonary tuberculosis patients who were scored as having tuberculosis on the basis of Mycobacterium tuberculosis-positive culture, the sensitivity of the serological test was lower than that of sputum smear microscopic examination (20.6% versus 80.9%, respectively; P < 0.000001).


Author(s):  
Retno Martini Widhyasih ◽  
Annisa Husnun Hanifah ◽  
Chairlan Chairlan ◽  
Dewi Inderiati

Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis. The diagnosis of pulmonary TB in general still relies on microscopic examination with a sputum smear for Acid Fast Basil (AFB). Microscopic examination to detect M. tuberculosis has high specificity, but the sensitivity is 35-70%. The sputum culture method is the gold standard for the diagnosis of pulmonary TB but requires a long time, which is 6-8 weeks. In recent years ICT (Immuno Chromatography Test) has been introduced to identify potential and useful TB antigens to help diagnose pulmonary TB. Antigens detected were ESAT-6, CFP-10, CFP-21, and MPT-64. This study aims to compare the results of the examination of specimens of suspect TB sputum with the ICT method and AFB. This study based on observational with analytic design cross-sectional on 56 samples of Stored Biological Material suspects TB that were examined by the AFB method and the ICT method (Cocktail Antigen). Statistical test results Fisher Exact (α = 0.05) showed no difference between microscopic examination of smear sputum and ICT (Cocktail Antigen) TB (p = 1,000). Nevertheless, the use of ICT reagents for the diagnosis of pulmonary TB still needs to be further investigated, especially to find out the exact causes of false positive and false negative reactions.


2019 ◽  
Author(s):  
Atiqa Ambreen ◽  
Muhammad Jamil ◽  
Muhammad Aqeelur Rahman ◽  
Tehmina Mustafa

Abstract Background Pulmonary tuberculosis (TB) with detectable Mycobacterium tuberculosis in the sputum is a major source of transmission. In resource limited TB endemic settings, cure is declared by sputum smear examination for acid fast bacilli without performing culture. This may lead to erroneous treatment outcomes as viable bacteria may be missed by low sensitivity of direct smear method of acid fast staining. The aim of this study was to investigate if sterilizing cure is achieved among the new pulmonary TB cases declared cured by sputum smear conversion and the impact of addition of ethambutol in the continuation phase in achieving sterilizing cure. Methods New sputum smear positive pulmonary TB patients registered at a tertiary care hospital in Pakistan were followed under standard Directly Observed Treatment Short Course strategy for six months. Half of these patients received ethambutol in addition to isoniazid and rifampicin in continuation phase. Sputum specimens were examined on microscopy at 2 months and end of treatment. Sputa of patients with negative direct smear examination at the end of treatment were cultured on solid medium. Results Total of 533 newly diagnosed sputum smear positive pulmonary TB patients were registered from November 2013 to March 2014. Among these 504 converted sputum negative at 2 months and 348 converted at the end of six months of treatment and declared cured. Sputa of 204/348 patients were cultured, and 12/204 (6%) were culture positive. Culture positivity at 6 month was not associated with bacterial load, smoking, diabetes, presence of cavities, history of contact with TB, age, gender, socioeconomic status, or addition of ethambutol in the continuation phase of treatment. Conclusion Six month treatment does not provide sterilizing cure in all pulmonary TB leading to risk for relapse. Direct smear examination is not enough to declare cure in TB patients. Addition of ethambutol in the continuation phase did not result in better sterilizing cure. These findings emphasize the importance of performing culture and follow-up of patients to monitor relapse in routine TB care. More studies are needed to find the optimal duration of treatment for individual or carefully selected groups of patients.


2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Pavithra S. Madamarandawala ◽  
Srinath Satyanarayana ◽  
Collins Timire ◽  
Aashifa Yaqoob ◽  
Dushantha Madegedara ◽  
...  

Mycobacterium tuberculosis belonging to Beijing sublineage (BL) is associated with high tuberculosis (TB) transmission, multidrug resistance, and adverse treatment outcomes. Sri Lanka experiences an increase in the number of travellers/workers to and from high TB-burden countries, and there is risk of getting BL strains imported into the country. In this context, a cohort study was conducted to assess the prevalence of BL strains among pulmonary tuberculosis (PTB) patients in the Kandy district of Sri Lanka (a popular tourist destination) and its association with patients’ sociodemographic and clinical characteristics. The study population included sputum smear-positive PTB patients diagnosed from February 2018–July 2019. Fresh sputum samples were collected for culturing and conducted polymerase chain reaction using BL-specific primers. Among the 101 patients recruited, presence of BL strains could be ascertained in 94 patients of which 24 (26%; 95% CI: 18%–35%) had BL strains. Prevalence of BL strains was higher among those with high sputum smear grades (2+ and 3+) (P<0.05) and those who had travelled abroad (P<0.05). The prevalence was also higher among young people (aged <35 years). Treatment success rates were similar in patients with (83%) and without BL strains (83% vs. 81%; P value = 0.8375). The prevalence of BL strains in Kandy, Sri Lanka, was high compared to previously reported figures in Sri Lanka, and the percentage drives closer to the countries in South East Asia. International travel raises itself as an emerging issue in BL transmission urging the need of policies and practices in immigration/emigration strategies. The study findings have the potential to alter the TB epidemiology in the country and might represent the situation in other underexplored countries as well. Therefore, it is important to monitor the trends and factors related to the prevalence of Beijing strains globally and make decisions as a whole.


2017 ◽  
Vol 1 ◽  
pp. 11 ◽  
Author(s):  
Benjamin Patterson ◽  
Carl Morrow ◽  
Vinayak Singh ◽  
Atica Moosa ◽  
Melitta Gqada ◽  
...  

Background: Tuberculosis (TB) is predominantly an airborne disease. However, quantitative and qualitative analysis of bio-aerosols containing the aetiological agent, Mycobacterium tuberculosis (Mtb), has proven very challenging. Our objective is to sample bio-aerosols from newly diagnosed TB patients for detection and enumeration of Mtb bacilli. Methods: We monitored each of 35 newly diagnosed, GeneXpert sputum-positive, TB patients during 1 hour confinement in a custom-built Respiratory Aerosol Sampling Chamber (RASC). The RASC (a small clean-room of 1.4m3) incorporates aerodynamic particle size detection, viable and non-viable sampling devices, real-time CO2 monitoring, and cough sound-recording. Microbiological culture and droplet digital polymerase chain reaction (ddPCR) were used to detect Mtb in each of the bio-aerosol collection devices. Results: Mtb was detected in 27/35 (77.1%) of aerosol samples; 15/35 (42.8%) samples were positive by mycobacterial culture and 25/27 (92.96%) were positive by ddPCR. Culturability of collected bacilli was not predicted by radiographic evidence of pulmonary cavitation, sputum smear positivity, or cough rate. Mtb was detected on all viable cascade impactor stages with a peak at aerosol sizes 2.0-3.5μm. This suggests a median of 0.09 CFU/litre of exhaled air (IQR: 0.07 to 0.3 CFU/l) for the aerosol culture positives and an estimated median concentration of 4.5x107 CFU/ml (IQR: 2.9x107-5.6x107) of exhaled particulate bio-aerosol. Conclusions: Mtb was identified in bio-aerosols exhaled by the majority of untreated TB patients using the RASC. Molecular detection was more sensitive than mycobacterial culture on solid media, suggesting that further studies are required to determine whether this reflects a significant proportion of differentially detectable bacilli in these samples.


Sign in / Sign up

Export Citation Format

Share Document