1. |
- Alaridah, Nader, et al.
(author)
-
Transmission dynamics study of tuberculosis isolates with whole genome sequencing in southern Sweden
- 2019
-
In: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 9
-
Journal article (peer-reviewed)abstract
- Epidemiological contact tracing complemented with genotyping of clinical Mycobacterium tuberculosis isolates is important for understanding disease transmission. In Sweden, tuberculosis (TB) is mostly reported in migrant and homeless where epidemiologic contact tracing could pose a problem. This study compared epidemiologic linking with genotyping in a low burden country. Mycobacterium tuberculosis isolates (n = 93) collected at Scania University Hospital in Southern Sweden were analysed with the standard genotyping method mycobacterial interspersed repetitive units-variable number tandem repeats (MIRU-VNTR) and the results were compared with whole genome sequencing (WGS). Using a maximum of twelve single nucleotide polymorphisms (SNPs) as the upper threshold of genomic relatedness noted among hosts, we identified 18 clusters with WGS comprising 52 patients with overall pairwise genetic maximum distances ranging from zero to nine SNPs. MIRU-VNTR and WGS clustered the same isolates, although the distribution differed depending on MIRU-VNTR limitations. Both genotyping techniques identified clusters where epidemiologic linking was insufficient, although WGS had higher correlation with epidemiologic data. To summarize, WGS provided better resolution of transmission than MIRU-VNTR in a setting with low TB incidence. WGS predicted epidemiologic links better which could consolidate and correct the epidemiologically linked cases, avoiding thus false clustering.
|
|
2. |
|
|
3. |
- Bryant, J. M., et al.
(author)
-
Emergence and spread of a human-transmissible multidrug-resistant nontuberculous mycobacterium
- 2016
-
In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 354:6313, s. 751-757
-
Journal article (peer-reviewed)abstract
- Lung infections with Mycobacterium abscessus, a species of multidrug-resistant nontuberculous mycobacteria, are emerging as an important global threat to individuals with cystic fibrosis (CF), in whom M. abscessus accelerates inflammatory lung damage, leading to increased morbidity and mortality. Previously, M. abscessus was thought to be independently acquired by susceptible individuals from the environment. However, using whole-genome analysis of a global collection of clinical isolates, we show that the majority of M. abscessus infections are acquired through transmission, potentially via fomites and aerosols, of recently emerged dominant circulating clones that have spread globally. We demonstrate that these clones are associated with worse clinical outcomes, show increased virulence in cell-based and mouse infection models, and thus represent an urgent international infection challenge.
|
|
4. |
- Jönsson, Bodil, 1959, et al.
(author)
-
Evaluation of the Cobas TaqMan MTB test for detection of Mycobacterium tuberculosis complex.
- 2015
-
In: Infectious diseases (London, England). - : Informa UK Limited. - 2374-4243 .- 2374-4235. ; 47:4, s. 231-6
-
Journal article (peer-reviewed)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).
|
|
5. |
- Jönsson, Bodil, 1959, et al.
(author)
-
TB can be detected with PCR – but only in smearpositive respiratory samples : Tbc kan påvisas med PCR – men bara i direktpositiva luftvägsprov
- 2018
-
In: Lakartidningen. - 0023-7205. ; 115:1-2
-
Research review (peer-reviewed)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.
|
|
6. |
- Larsson, Lars-Olof, et al.
(author)
-
Nontuberculous Mycobacterial Diseases in Humans
- 2019
-
In: Nontuberculous Mycobacteria (NTM) - Microbiolocical, Clinical and Geografical distribution) / Editors: Ali Akbar and Parissa Farnia. - : Academic Press. - 9780128146927 ; , s. 101-119
-
Book chapter (peer-reviewed)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.
|
|