| 1. |
- Antusheva, E., et al.
(författare)
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Outbreak of tuberculosis in a closed setting: views on transmission based on results from molecular and conventional methods
- 2016
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Ingår i: Journal of Hospital Infection. - : Elsevier BV. - 0195-6701. ; 93:2, s. 187-190
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Tidskriftsartikel (refereegranskat)abstract
- Background: This study describes an outbreak of tuberculosis (TB) in a nursing home for men with mental disorders where residency is lengthy or permanent. This type of setting can provide a model of transmission as contact with the rest of society is extremely limited. Aim: To determine if cases of TB, diagnosed around the same time and in the same place, are linked based on results using molecular and conventional methods. Methods: The strains of Mycobacterium tuberculosis were analysed by drug resistance testing and mycobacterial interspersed repetitive units-variable number tandem repeats (MIRU-VNTRV). Microbiological results were related to clinical history and time of diagnosis. Findings: Nine patients were diagnosed with TB, and strains were recovered from seven of these patients. Unexpectedly, the strains with the same genotype showed different patterns of resistance, and only two strains demonstrated identical patterns. MIRU-VNTR analysis demonstrated that one patient was infected with two different strains. Conclusion: Variation between the strains indicates that the outbreak may have arisen from several sources of infection. The variation in resistance indicates that rapid emergence of antimicrobial resistance is possible. As such, several questions are raised concerning source of infection, development of disease, resistance and mixed infections. (C) 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
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| 2. |
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| 3. |
- Jankute, M., et al.
(författare)
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The role of hydrophobicity in tuberculosis evolution and pathogenicity
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- The evolution of tubercle bacilli parallels a route from environmental Mycobacterium kansasii, through intermediate "Mycobacterium canettii", to the modern Mycobacterium tuberculosis complex. Cell envelope outer membrane lipids change systematically from hydrophilic lipooligosaccharides and phenolic glycolipids to hydrophobic phthiocerol dimycocerosates, di-and pentaacyl trehaloses and sulfoglycolipids. Such lipid changes point to a hydrophobic phenotype for M. tuberculosis sensu stricto. Using Congo Red staining and hexadecane-aqueous buffer partitioning, the hydrophobicity of rough morphology M. tuberculosis and Mycobacterium bovis strains was greater than smooth "M. canettii" and M. kansasii. Killed mycobacteria maintained differential hydrophobicity but defatted cells were similar, indicating that outer membrane lipids govern overall hydrophobicity. A rough M. tuberculosis H37Rv Delta papA1 sulfoglycolipid-deficient mutant had significantly diminished Congo Red uptake though hexadecane-aqueous buffer partitioning was similar to H37Rv. An M. kansasii, Delta MKAN27435 partially lipooligosaccharide-deficient mutant absorbed marginally more Congo Red dye than the parent strain but was comparable in partition experiments. In evolving from ancestral mycobacteria, related to "M. canettii" and M. kansasii, modern M. tuberculosis probably became more hydrophobic by increasing the proportion of less polar lipids in the outer membrane. Importantly, such a change would enhance the capability for aerosol transmission, affecting virulence and pathogenicity.
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| 4. |
- Jönsson, Bodil, 1959, et al.
(författare)
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Evaluation of the Cobas TaqMan MTB test for detection of Mycobacterium tuberculosis complex.
- 2015
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Ingår i: Infectious diseases (London, England). - : Informa UK Limited. - 2374-4243 .- 2374-4235. ; 47:4, s. 231-6
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Tidskriftsartikel (refereegranskat)abstract
- The Cobas TaqMan MTB assay is used for rapid detection of the Mycobacterium tuberculosis complex (MTC) in clinical samples. It is only validated for respiratory samples, but is often requested by physicians for non-respiratory specimens. The aim of this study was therefore to evaluate the performance of this assay in clinical praxis in a country with low prevalence of tuberculosis (TB).
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| 5. |
- Jönsson, Bodil, 1959, et al.
(författare)
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TB can be detected with PCR – but only in smearpositive respiratory samples : Tbc kan påvisas med PCR – men bara i direktpositiva luftvägsprov
- 2018
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Ingår i: Lakartidningen. - 0023-7205. ; 115:1-2
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Forskningsöversikt (refereegranskat)abstract
- Unnecessary and inappropriate clinical requests represent a great waste of time and money and may also result in false diagnoses. PCR techniques, such as Cobas TaqMan MTB, are used for rapid detection of tuberculosis (TB). These assays are only validated for respiratory specimens, but they are commonly requested also for non-respiratory specimens. These assays perform well in smear-positive respiratory samples, while the sensitivities are quite unsatisfactory for both respiratory and non-respiratory smearnegatives samples. The specificity is high and it is possible to rapidly distinguish between TB and infections caused by environmental mycobacteria. The analyses demonstrate, furthermore, that PCR assays cannot be used to evaluate treatment, detect relapses or exclude TB. Nor can these assays be used to evaluate contagiousness or to screen for TB. © 2017, Swedish Medical Association. All rights reserved.
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| 6. |
- Larsson, Lars-Olof, et al.
(författare)
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Nontuberculous Mycobacterial Diseases in Humans
- 2019
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Ingår i: Nontuberculous Mycobacteria (NTM) - Microbiolocical, Clinical and Geografical distribution) / Editors: Ali Akbar and Parissa Farnia. - : Academic Press. - 9780128146927 ; , s. 101-119
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Bokkapitel (refereegranskat)abstract
- The number of patients infected with nontuberculous mycobacteria (NTM) is increasing and presents severe health problems. NTM infections in children are not uncommon and differ in several aspects from NTM infections in adults. In children, lymph nodes are most often infected, while lung infections dominate among adults. Thus, this chapter on NTM infections will focus on infections in children and pulmonary infections in adults. The reason why NTM diseases have been more commonly recognized is partly due to increased awareness and improved diagnostic methods. In addition, the number of patients with impaired resistance to infections has increased and such conditions are important risk factors for developing NTM disease. However, many NTM patients, particularly children, have no known predisposing condition. In addition, spontaneous resolution is common among children. Diagnosis and treatment are challenging since many patients suffer from other diseases and many NTM are resistant to commonly used drugs. Therapy is, therefore, generally complex and prolonged and side effects are common.
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| 7. |
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| 8. |
- Petrini, Björn, et al.
(författare)
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Lungsjukdom med icke-tuberkulösa mykobakterier
- 2015
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Ingår i: Lungmedicin. Redaktörer: Thomas Sandström, Anders Eklund. - Lund : Studentlitteratur. - 9789144084190 ; , s. 303-310
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Bokkapitel (refereegranskat)
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| 9. |
- Ridell, Malin, 1942
(författare)
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New options in Tuberculosis Care: Visions for the future are crucial for controlling the disease.
- 2016
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Ingår i: International journal of mycobacteriology. - : Medknow. - 2212-554X .- 2212-5531. ; 5:Suppl 1
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Forskningsöversikt (refereegranskat)abstract
- The current strategies for controlling tuberculosis (TB) are not sufficient. Improved prophylactic and diagnostic tools are imperative, being crucial for decreasing TB incidence and mortality and for preventing outbreaks. Furthermore, new and better drugs are badly needed, particularly considering the increase in cases with multidrug-resistant strains. The current TB vaccine-the Bacillus Calmette-Guérin vaccine-has a preventive impact on disseminated TB in children, but little effect on the most common form of TB, that is, lung TB in adults and young adults. For many years extensive scientific efforts have been made in order to develop new vaccines against TB that are better and more effective than Bacillus Calmette-Guérin. No such vaccine exists, however, to date. During the last few years it has become increasingly clear that TB patients can be infected with more than one strain and that a previous TB infection increases rather than decreases the risk for getting a new one. Mycobacterium tuberculosis organisms are thus not capable of inducing protective immunity to such an extent that a new TB infection is prevented. This phenomenon highlights the problems of developing effective vaccines against TB. A new TB vaccine based on general immunological protection models would in all probability only have a limited capacity to hamper TB incidence and mortality. The question whether or not it is feasible to make a vaccine of sufficient efficacy must therefore be discussed. Prophylaxis is practically always far better than therapy and we all wish we had an effective TB vaccine. However, considering the problems with vaccines, scientific efforts could well focus on developing new therapies rather than new vaccines. New scientific approaches are highly necessary and we need ideas and visions. Some examples of recent projects will hereby be presented. One study concerns the mycobacterial cell envelope and its unique macromolecules as targets for new drugs. Another study concerns new ways of administrating the drugs which could enhance the effects of new as well as of already available drugs. In addition, what can be learnt from cancer therapy-is supporting the patient's own defense by immune modularly methods a possible approach? We also need to look back since ample knowledge on TB has been assembled during many years. Unfortunately some of this valuable knowledge is about to be forgotten, particularly, the experience from the time when TB was an incurable disease.
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