International Journal of Mycobacteriology最新文献

Background: The overexpression of efflux pumps (Eps) was reported to contribute to multidrug resistant tuberculosis (MDR-TB). Increases in Eps that expel structurally unrelated drugs contribute to reduced susceptibility by decreasing the intracellular concentration of antibiotics. In the present study, an association of mycobacterial membrane protein (MmpS5-MmpL5) Ep and its gene regulator (Rv0678) was investigated in MDR-tuberculosis isolates.

Methods: MTB strains were isolated from patients at two different intervals, i.e., once when they had persistent symptoms despite 3-15 ≥ months of treatment and once when they had started new combination therapy ≥2-3 months. Sputum specimens were subjected to Xpert MTB/rifampicin test and then further susceptibility testing using proportional method and multiplex polymerase chain reaction (PCR) were performed on them. The isolates were characterized using both 16S-23S RNA and hsp65 genes spacer (PCR-restriction fragment length polymorphism). Whole-genome sequencing (WGS) was investigated on two isolates from culture-positive specimen per patient. The protein structure was simulated using the SWISS-MODEL. The input format used for this web server was FASTA (amino acid sequence). Protein structure was also analysis using Ramachandran plot.

Results: WGS documented deletion, insertion, and substitution in transmembrane transport protein MmpL5 (Rv0676) of Eps. Majority of the studied isolates (n = 12; 92.3%) showed a unique deletion mutation at three positions: (a) from amino acid number 771 (isoleucine) to 776 (valine), (b) from amino acid number 785 (valine) to 793 (histidine), and (c) from amino acid number 798 (leucine) to 806 (glycine)." One isolate (7.6%) had no deletion mutation. In all isolates (n = 13; 100%), a large insertion mutation consisting of 94 amino acid was observed "from amino acid number 846 (isoleucine) to amino acid number 939 (leucine)". Thirty-eight substitutions in Rv0676 were detected, of which 92.3% were identical in the studied isolates. WGS of mycobacterial membrane proteins (MmpS5; Rv0677) and its gene regulator (Rv0678) documented no deletion, insertion, and substitution. No differences were observed between MmpS5-MmpL5 and its gene regulator in isolates that were collected at different intervals.

Conclusions: Significant genetic mutation like insertion, deletion, and substitution within transmembrane transport protein MmpL5 (Rv0676) can change the functional balance of Eps and cause a reduction in drug susceptibility. This is the first report documenting a unique amino acid mutation (insertion and deletion ≥4-94) in Rv0676 among drug-resistant MTB. We suggest the changes in Mmpl5 (Rv0676) might occurred due to in-vivo sub-therapeutic drug stress within the host cell. Changes in MmpL5 are stable and detected through subsequent culture-positive specimens.

Background: Tuberculosis (TB) and coronavirus disease 2019 (COVID-19) are the top two killers of infectious disease. We aimed to determine the association of TB coinfection with the inhospital mortality of COVID-19 patients in Indonesia as a TB-endemic country.

Methods: We conducted a retrospective cohort study in a tertiary lung hospital in Indonesia. All TB-coinfected COVID-19 patients who were hospitalized between January 2020 and December 2021 were included in the study. COVID-19 patients without TB were randomly selected for the control group. Clinical characteristics and laboratory results were assessed. Survival analysis was performed to determine the estimated death rate and median survival time (MST). Multivariate Cox regression analysis was conducted to define the association of TB coinfection with the in-hospital mortality of COVID-19.

Results: We included 86 (8.3%) TB coinfections among 1034 confirmed COVID-19 patients. TB coinfection patients had younger age, malnutrition, and different symptoms compared to the COVID-19 group. TB-coinfected patients had a lower estimated death rate than the COVID-19 group (6.5 vs. 18.8 per 1000 population). MST in the COVID-19 group was 38 (interquartile range 16-47) days, whereas the same observation time failed to determine the MST in the TB coinfection group. TB coinfection had a crude hazard ratio of mortality 0.37 (95% confidence interval [CI] 0.15-0.94, P = 0. 004). The final model analysis including age, sex, and lymphocyte as confounding factors resulted in an adjusted HR of mortality 0.31 (95% CI 0.1-0.9).

Conclusion: This study showed TB coinfection was negatively associated with the in-hospital mortality of COVID-19.

Background: Tuberculosis (TB) remains a global public health issue, impacting millions of people worldwide. This study determined the outcomes of TB treatment managed within a 10 year period at the Bamenda Regional Hospital in Cameroon.

Methods: A retrospective study was carried out among 2428 patients diagnosed and treated for active TB infection from 2013 to 2022, at the Bamenda Regional Hospital. Data collection was done from March to April 2023 using a data extraction form. Bivariate and multivariate logistic regression models were used to identify factors associated with successful TB treatment outcomes. Data was analyzed using SPSS software version 26.

Results: Of the 2428 patients with TB, 1380 (56.8%) were cured, 739 (30.4%) completed treatment, treatment failures were recorded in 10 (0.4%) patients, and 200 (8.2%) died during or after receiving treatment. Treatment default was the outcome in 99 (4.1%). Successful treatment outcomes were reported in 2119 (87.3%). Patients within age groups 41-50 (P = 0.010), 51-60 (P = 0.041), and >60 years (P = 0.006), male (P = 0.004), and human immunodeficiency virus-positive patients (P < 0.001) had decreased odds of successful treatment outcomes.

Conclusion: The outcomes of treatment within a 10 year period showed that the treatment success was 2.7% below the World Health Organizations target. Prioritizing vulnerable patient groups in TB management and implementing public health interventions such as financial assistance and nutritional support will go a long way in improving treatment outcomes.

Background: The study aimed to report all cases of oral tuberculosis (TB), a rare manifestation of the fatal infectious disease primarily affecting the pulmonary system. The report also evaluated the clinicopathological characteristics of oral TB lesions.

Methods: A total of 25 patients who presented with oral lesions between August 2013 and August 2023 were diagnosed with TB through surgical biopsy despite having no prior history of the disease. Their clinical symptoms, auxiliary examinations, treatments, and outcomes were recorded and analyzed for further study.

Results: In a study of 25 patients with oral TB, all patients were found to have the disease, with 16 males and 9 females affected. The gender distribution was skewed toward males, with a 1.77 male-to-female ratio. Twelve cases of the affected sites were reported in the mandible, six cases in the buccal mucosa, four in the lips, two in the gingiva, and one in the tongue. The age range of affected patients was 0-70 years old, and all lesions were indicative of primary TB. The appearance of the affected mucosa varied, with ulceration and swelling being the most common manifestations.

Conclusion: Patients who present with oral ulcerations and swellings should be evaluated for the possibility of TB. To confirm and differentiate this condition from other diseases, obtaining a biopsy specimen for histological analysis and performing acid-fast stains and cultures is recommended. These tests will enable a precise diagnosis and guide appropriate treatment.

Background: The coinfection of Mycobacterium tuberculosis and SARS-CoV-2 is called tuberculosis and COVID-19 coinfection (TB-COVID-19). We aimed to share the clinical, radiological, and laboratory findings and treatment processes of our patients with TB-COVID-19 coinfection in our tertiary reference hospital.

Methods: Patients aged 18 years and over and hospitalized in the tuberculosis service between March 2020 and September 2022 were included. All coinfected patients whose COVID-19 polymerase chain reaction results were positive while receiving tuberculosis treatment or who were diagnosed with tuberculosis while receiving treatment for COVID-19 were included.

Results: The number of patients was 39; 61.6% of males; the mean age was 52 ± 17.1 years; 20% were foreign nationals; 92.5% were Asian; 69.5% had a bacteriological diagnosis; 84.6% had pulmonary tuberculosis; 10% had received antituberculosis treatment before; and 87.5% were sensitive to the first-line antituberculosis drugs. The most common comorbidities were diabetes and hypertension. 87.5% of the patients were diagnosed with tuberculosis and were superinfected with COVID-19 while receiving tuberculosis treatment. 49.5% of patients had received at least one dose of COVID-19 vaccine. The most common presenting symptom was cough and sputum; the prominent laboratory parameter was C-reactive protein increase, and thorax computed tomography finding was consolidation, tree-in-bud, and cavitation. While 45.9% of the patients were still under treatment, 1 (2.5%) patient also resulted in mortality.

Conclusion: In this study, attention was drawn to two infectious diseases seen with respiratory tract symptoms. The mortality rate was found to be low. Neither disease was found to be a factor aggravating the course of each other.

Abstract: Tuberculosis (TB) remains a significant global health concern and kills millions of people every year. While TB can affect any organ in the body, breast TB is relatively uncommon. This study presents a comprehensive review of literature spanning 23 years, with a focus on cases of breast TB in Iran. Among the 96 cases found, the majority (89.6%) fell within the age range of 20-60, with a striking prevalence among women (98.9%). Common symptoms included pain and palpable mass, each presenting in approximately 60.4% of cases. Notably, only a quarter of patients had a confirmed history of exposure to a known TB case. Left breast involvement was more prevalent (58.3%), with ipsilateral lymph node enlargement observed in 40.6% of cases. Given the clinical presentation of breast TB, which often leads to misdiagnosis, a significant proportion of cases (68.7%) were diagnosed through excisional biopsy. Following a standard 6-month regimen of anti-TB drugs, relapse occurred in only 4.2% of cases. This study highlights the need for heightened awareness and vigilance in diagnosing breast TB, especially in regions with a high burden. Although breast TB poses diagnostic challenges, with prompt identification and treatment, the prognosis is generally favorable, with a low incidence of relapse.

Background: Smear microscopy for acid-fast bacilli visualization is important to assess the infectivity rate in patients with pulmonary tuberculosis (PTB), but it has limited sensitivity; hence, it is important to find an alternative strategy. The aim of our study was to compare the fluorescence microscopy grading by Auramine O phenol staining technique of respiratory samples with the cyclic threshold (Ct) values of GeneXpert Ultra (Mycobacterium tuberculosis/rifampicin [MTB/RIF]) and assess the diagnostic efficacy of GeneXpert Ultra (MTB/RIF) compared to microscopy in suspected cases of PTB.

Methods: The study was conducted in the Mycobacteriology Laboratory, Department of Microbiology, in Kasturba Hospital, Manipal. The study was a prospective, single-centered, cross-sectional study. Four hundred and fifty-two respiratory samples were included in the study. An optimal Ct cutoff value for ruling smear-positivity and smear-negativity and the mean Ct cutoff value were calculated. Clinical and radiological data from the requisition forms were assessed. IBM SPSS statistics software version 22 was used. The correlation between GeneXpert Ultra (MTB/RIF) Ct values and smear status was calculated by polychoric correlation. The extended McNemar's test was used to find the association between the variables.

Results: GeneXpert Ultra (MTB/RIF) yielded a higher positivity rate of 22.2% compared to smear microscopy 17.2%. Ct value and smear grading yielded a positive correlation (P = 0.8681; P < 0.05). GeneXpert Ultra (MTB/RIF) yielded nontuberculous mycobacteria in five undetected cases and speciated as Mycobacterium abscessus complex.

Conclusions: Our study confirms the GeneXpert Ultra (MTB/RIF) Ct value levels as a predictor of smear positivity.

Tuberculosis (TB) is considered a common infection in developing countries and is caused by various strains of mycobacteria, usually Mycobacterium TB. TB remains to be one of the most important health threats. TB can have varied clinical presentations; Pulmonary TB affects the lungs and extrapulmonary TB (EPTB) can affect any part of the body. Cervical tuberculous lymphadenitis (CTL), cervical lymphadenitis, which is also referred to as scrofula is a case of EPTB that most frequently involves the cervical lymph nodes. In our report, a case of a young patient with CTL has been reported. This case's physical examination, evolution, diagnosis, and treatment have been discussed. Our case exemplifies the potential manifestations of an extrapulmonary tubercular lesion of the posterior pharyngeal wall, demonstrating that mycobacteria can infect practically any human organ. A high index of suspicion is critically required for the diagnosis of tuberculous lymphadenitis as mimics a number of pathological conditions.

Background: Tuberculous meningitis (TBM) is caused by the dissemination of Mycobacterium tuberculosis (MTB) from the primary site of infection to the central nervous system. However, the bacterial factors associated with the pathogenesis of TBM remain unclear. This study employed transcriptomic and proteomic methods to comprehensively analyze the changes in genes and proteins and their associated pathways in MTB strains isolated from cerebrospinal fluid (CSF) of TBM and sputum of pulmonary TB (PTB) cases.

Methodology: Five MTB strains were subjected to OMICs (transcriptomic and proteomic) analysis. Among five MTB strains, two were isolated from CSF and sputum samples of the same patient with PTB and TBM infections, one from the sputum of a different PTB patient, and a strain obtained from the CSF of another TBM patient. H37Rv was used as a reference strain. The reliability of transcriptomic results was validated by real time polymerase chain reaction with selected genes from 100 MTB isolates (CSF, 50 and sputum, 50).

Results: The transcriptomic study revealed that overlapping differentially expressed genes of MTB strains isolated from TBM patients showed featured enrichment in benzoate degradation, lysine degradation, tryptophan metabolism, fatty acid degradation, ATP binding cassette transporters, microbial metabolism in diverse environments, biosynthesis of antibiotics, and metabolic pathways. Eleven genes were upregulated, and four were downregulated in MTB strains isolated from TBM compared to PTB. From proteomic analysis, we identified three candidate proteins belonging to plasminogen binding proteins (PBP) (enolase, dnaK, and isocitrate lyase 1) that were significantly upregulated in MTB strains isolated from TBM.

Conclusion: Overall, the transcriptomic and proteomic analyses provided an important base for understanding the unique feature of TBM pathogenesis. To the best of our knowledge, this is the first report highlighting the importance of PBPs on TBM pathogenesis.

Background: Tuberculosis (TB) is one of the oldest and deadliest infectious diseases known to affect human health, which is gaining renewed importance today.

Methods: In our center, which is a tertiary research hospital, the data of patients hospitalized due to TB between 2011 and 2022 were retrospectively identified by searching the database.

Results: Six women (30.0%) and 14 men (70.0%) were included in the study. When analyzed by age grouping, four patients between the ages of 19 and 34 years (20.0%), five patients between the ages of 38 and 58 years (25.0%), five patients aged 61-69 years (25.0%), and six patients aged 70-81 years (30.0%). Radiographs showed cavitation in 9 (45.0%) patients, and 11 (55.0%) patients had no radiologic findings. The ARS results of the participants showed that there were 7 (35.0%) patients positive and 13 (65.0%) patients negative. When the TB culture variables of the participants were analyzed, it was found that there were 5 (25.0%) people with no growth and 15 (75.0%) people with growth. Concurrent diseases were noted in patients including 5 (25.0%) with organ transplantation, 3 (15.0%) with diabetes mellitus, 2 (%10) with cancer, and 2 (10%) with chronic renal failure according to the chart records. The distribution of cases was as follows: 19 (95.0%) pulmonary TB and 1 (5.0%) pleural TB. It was found that there were 5 (25.0%) people with a history of TBC and 15 people (75.0%) without a history of TBC. Moreover, drug susceptibility tests showed that 5 (25%) patients of the isolates were identified as multidrug resistant with first-line drug susceptibility testing.

Conclusion: The study was not financially supported by any individual/organization, and the authors have no vested interests.