Endogenous reactivation cases identified by whole genome sequencing of : Exploration of possible causes in Latvian tuberculosis patients.

Background: The recurrence of tuberculosis (TB) continues to place a significant burden on patients and TB programs worldwide. Repeated TB episodes can develop either due to endogenous reactivation of previously treated TB or exogenous reinfection with a distinct strain of (Mtb). Determining the precise cause of the recurrent TB episodes and identifying reasons for endogenous reactivation of previously successfully treated patients is crucial for introducing effective TB control measures.

Discordance Between Phenotypic and WGS-Based Drug Susceptibility Testing Results for Some Anti-Tuberculosis Drugs: A Snapshot Study of Paired Isolates with Small Genetic Distance.

Background: Current tuberculosis treatment regimens primarily rely on phenotypic drug susceptibility testing and rapid molecular assays. Although whole-genome sequencing (WGS) offers a promising alternative, disagreements between phenotypic and molecular testing methods remain. In this retrospective study, we compared the phenotypic and WGS-predicted drug resistance profiles of paired isolates with small genetic distances (≤10 single nucleotide variants) obtained from patients with longitudinal single-episode or recurrent tuberculosis.

Unraveling tuberculosis patient cluster transmission chains: integrating WGS-based network with clinical and epidemiological insights.

Background: Tuberculosis remains a global health threat, and the World Health Organization reports a limited reduction in disease incidence rates, including both new and relapse cases. Therefore, studies targeting tuberculosis transmission chains and recurrent episodes are crucial for developing the most effective control measures. Herein, multiple tuberculosis clusters were retrospectively investigated by integrating patients' epidemiological and clinical information with median-joining networks recreated based on whole genome sequencing (WGS) data of isolates.

Effect of NAT2, GSTM1 and CYP2E1 genetic polymorphisms on plasma concentration of isoniazid and its metabolites in patients with tuberculosis, and the assessment of exposure-response relationships.

Isoniazid is a key drug in the chemotherapy of tuberculosis (TB), however, interindividual variability in pharmacokinetic parameters and drug plasma levels may affect drug responses including drug induced hepatotoxicity. The current study investigated the relationships between isoniazid exposure and isoniazid metabolism-related genetic factors in the context of occurrence of drug induced hepatotoxicity and TB treatment outcomes. Demographic characteristics and clinical information were collected in a prospective TB cohort study in Latvia ( = 34).

Tuberculosis Disease in Immunocompromised Children and Adolescents: A Pediatric Tuberculosis Network European Trials Group Multicenter Case-control Study.

Background: In high-resource settings, the survival of children with immunocompromise (IC) has increased and immunosuppressive therapies are increasingly being used. This study aimed to determine the clinical characteristics, performance of diagnostic tools, and outcome of IC children with tuberculosis (TB) in Europe.

Methods: Multicenter, matched case-control study within the Pediatric Tuberculosis Network European Trials Group, capturing TB cases <18 years diagnosed 2000-2020.

Exploring Variability in Rifampicin Plasma Exposure and Development of Anti-Tuberculosis Drug-Induced Liver Injury among Patients with Pulmonary Tuberculosis from the Pharmacogenetic Perspective.

Genetic polymorphisms can exert a considerable impact on drug pharmacokinetics (PK) and the development of adverse drug reactions (ADR). However, the effect of genetic polymorphisms on the anti-tuberculosis (anti-TB) drug, and particularly rifampicin (RIF), exposure or anti-TB drug-induced liver injury (DILI) remains uncertain. Here, we evaluated the relationship between single nucleotide polymorphisms (SNPs) detected in the RIF pharmacogenes (, , , , and ) and RIF PK parameters, as well as anti-TB treatment-associated DILI.

Genotypic and phenotypic comparison of drug resistance profiles of clinical multidrug-resistant Mycobacterium tuberculosis isolates using whole genome sequencing in Latvia.

Background: Multidrug-resistant tuberculosis (MDR-TB) remains a major public health problem in many high tuberculosis (TB) burden countries. Phenotypic drug susceptibility testing (DST) take several weeks or months to result, but line probe assays and Xpert/Rif Ultra assay detect a limited number of resistance conferring gene mutations. Whole genome sequencing (WGS) is an advanced molecular testing method which theoretically can predict the resistance of M.

Advantages of analysing both pairwise SNV-distance and differing SNVs between isolates for recurrent tuberculosis cause determination.

Endogenous reactivation and exogenous reinfection are two possible causes of recurrent tuberculosis (TB). However, in some cases, precise cause determination can be challenging. In this study, we used whole genome sequencing to determine pairwise SNV distances and detect differing SNVs in initial and subsequent isolates for recurrent TB cases when the first and second episodes were caused by () strains with an identical spoligotype pattern.

Performance of QuantiFERON-TB Gold Plus assays in paediatric tuberculosis: a multicentre PTBNET study.

Rationale: In 2016, a new interferon-gamma release assay (IGRA) was introduced, QuantiFERON-TB Gold Plus (QFT-Plus), claimed to have improved sensitivity in active tuberculosis (TB).

Objectives: This study aimed to determine the performance of QFT-Plus, compared with previous generation IGRAs and the tuberculin skin test (TST), in children with TB in Europe.

Methods: Multicentre, ambispective cohort study within the Paediatric Tuberculosis Network European Trials Group (ptbnet), a dedicated paediatric TB research network comprising >300 members, capturing TB cases <18 years-of-age diagnosed between January 2009 and December 2019.

Application of whole-genome sequencing in a case study of renal tuberculosis in a child.

Background: Urogenital tuberculosis (TB) is rare in children and usually develops due to reactivation of the foci in the genitourinary tract after the latency period following initial infection. Urogenital TB in children has no pathognomonic clinical features that can result in overlooking or misdiagnosing this clinical entity. Here, we report important findings regarding the pathogenesis and transmission of TB by using genotyping and whole-genome sequencing (WGS) in a study of renal TB case in a child.

Tuberculosis Disease in Children and Adolescents on Therapy With Antitumor Necrosis Factor-ɑ Agents: A Collaborative, Multicenter Paediatric Tuberculosis Network European Trials Group (ptbnet) Study.

Background: In adults, anti-tumor necrosis factor-α (TNF-α) therapy is associated with progression of latent tuberculosis (TB) infection (LTBI) to TB disease, but pediatric data are limited.

Methods: Retrospective multicenter study within the Paediatric Tuberculosis Network European Trials Group, capturing patients <18 years who developed TB disease during anti-TNF-α therapy.

Results: Sixty-six tertiary healthcare institutions providing care for children with TB participated.

Analysis of Mycobacterium tuberculosis genetic lineages circulating in Riga and Riga region, Latvia, isolated between 2008 and 2012.

Although the number of new tuberculosis (TB) cases registered per year has decreased by 3-fold between 2001 and 2017 in Latvia, the TB incidence and rates of multidrug resistant TB in this Baltic country remain substantially higher than in most other European countries. Molecular typing methods of Mycobacterium tuberculosis (MTB) play an important role both in clinical studies of the disease and the epidemiological investigations, allowing to describe and characterize the pathogen's population structure and spread of particular genotypes. Aim of this study was to examine the prevalence of MTB lineages in Riga and Riga region of Latvia within a five-year period (2008-2012), and to evaluate the discriminatory power (DP) of spoligotyping, standard 24-locus MIRU-VNTR and IS6110-RFLP methods in this setting.

Treatment Outcomes in Global Systematic Review and Patient Meta-Analysis of Children with Extensively Drug-Resistant Tuberculosis.

Extensively drug-resistant tuberculosis (XDR TB) has extremely poor treatment outcomes in adults. Limited data are available for children. We report on clinical manifestations, treatment, and outcomes for 37 children (<15 years of age) with bacteriologically confirmed XDR TB in 11 countries.

Treatment and outcomes in children with multidrug-resistant tuberculosis: A systematic review and individual patient data meta-analysis.

Background: An estimated 32,000 children develop multidrug-resistant tuberculosis (MDR-TB; Mycobacterium tuberculosis resistant to isoniazid and rifampin) each year. Little is known about the optimal treatment for these children.

Methods And Findings: To inform the pediatric aspects of the revised World Health Organization (WHO) MDR-TB treatment guidelines, we performed a systematic review and individual patient data (IPD) meta-analysis, describing treatment outcomes in children treated for MDR-TB.

Acquires Limited Genetic Diversity in Prolonged Infections, Reactivations and Transmissions Involving Multiple Hosts.

(MTB) has limited ability to acquire variability. Analysis of its microevolution might help us to evaluate the pathways followed to acquire greater infective success. Whole-genome sequencing (WGS) in the analysis of the transmission of MTB has elucidated the magnitude of variability in MTB.

Genotypic and phenotypic characteristics of aminoglycoside-resistant Mycobacterium tuberculosis isolates in Latvia.

Mutations causing resistance to aminoglycosides, such as kanamycin (KAN), amikacin (AMK), and streptomycin, are not completely understood. In this study, polymorphisms of aminoglycoside resistance influencing genes such as rrs, eis, rpsL, and gidB in 41 drug-resistant and 17 pan-sensitive Mycobacterium tuberculosis clinical isolates in Latvia were analyzed. Mutation A1400G in rrs gene was detected in 92% isolates with high resistance level to KAN and diverse MIC level to AMK.