International Journal of Mycobacteriology最新文献

Introduction: Tuberculosis (TB) is a significant global health issue, with posttreatment fibrosis negatively affecting pulmonary function and patient quality of life. This research investigated the processes driving post-TB pulmonary fibrosis and its impact on patients.

Methods: This research involved a cohort of 38 pulmonary TB patients undergoing intensive treatment for 2 months. Transforming Growth Factor Beta (TGFβ) and Small Mothers Against Decapentaplegic 3 (SMAD3) levels were quantified pre- and posttreatment using the Enzyme Linked Immuno Sorbent Assay method. Fibrosis was evaluated via thoracic imaging, and lung function was assessed through spirometry.

Results: TGFβ and SMAD3 levels were decreased post-treatment (P = 0.03 and P = 0.01). A significant association existed between postintervention SMAD3 levels and the occurrence of fibrosis (P = 0.03) and diminished lung function (P = 0.01). Receiver operating characteristic analysis indicated that post-intervention SMAD3 exhibited an area under the curve of 0.8, with a sensitivity of 87% and specificity of 71%, suggesting its potential as a biomarker for fibrosis.

Conclusion: Levels of TGFβ and SMAD3 following pulmonary TB treatment are linked to fibrosis and reduced lung function. SMAD3 post-intervention may be a fibrosis biomarker in pulmonary TB patients.

Background: Nontuberculous mycobacteria (NTM) are ubiquitous organisms with varied clinical syndromes. We conducted this study to identify the clinical spectrum, microbiological diagnosis, outcomes, and predictors of outcome in patients with NTM bloodstream infections (NTM BSIs).

Methods: This is a retrospective study of patients diagnosed with NTM BSI from January 2005 to December 2024. Poor outcomes were defined as patients who either expired or were lost to follow-up after being discharged against medical advice, subsequent to a poor prognosis.

Results: A total of 40 patients with NTM BSI were included. The median age was 43 years with male predominance (n = 25, 62.5%). Associated risk factors included human immunodeficiency virus (HIV) infection (n = 18, 45%) with a median CD4 count of 18 cells/mm3, diabetes mellitus (n = 7, 31.8%), and immunosuppressive medication use (n = 6, 27.3%). The spectrum of infections among HIV-negative patients (n = 22) were disseminated infection (n = 6), coronary stent infection (n = 5), infective endocarditis (n = 4), catheter-related BSI (n = 4), pacemaker lead infection (n = 1), aortic stent infection (n = 1), thecoperitoneal shunt infection (n = 1), and infected bedsore (n = 1). All HIV-positive patients presented with disseminated NTM infection. Poor outcome for NTM BSI was seen in 64.9% of patients. Among the rapid growers, Mycobacterium abscessus complex had the worst prognosis with a poor outcome in 71.4% of patients.

Conclusion: The spectrum of diseases associated with NTM BSI was either disseminated disease in an immunosuppressed host or infection secondary to nosocomial contamination of a catheter, implant, or stent. NTM BSI is associated with poor prognosis. This underscores the need for early diagnosis, appropriate antibiotic therapy, and adequate source control to improve clinical outcomes.

Background: Tuberculosis (TB) caused by Mycobacterium tuberculosis (M. tb) complex remains a leading cause of morbidity and mortality worldwide. The zoonotic infectious condition represents a never-ending challenge for which drug discovery efforts are needed. The current study was designed to evaluate the in vitro antimycobacterial activity and phytochemical composition of hydroethanolic extracts from roots, stem bark, leaves, and unripe fruits derived from Solanum torvum, a shrub traditionally used against respiratory tract illnesses, including TB.

Methods: The phenotypic colorimetric microplate alamar blue assay was used to study the antimycobacterial activity of the hydroethanolic extracts against six mycobacterial strains. Each experiment was run in triplicate. Data generated were analyzed using descriptive statistics to obtain mean minimum inhibitory concentration (MIC) values.

Results: The roots, stem bark, leaves, and unripe fruits exhibited MIC values of 0.0195 mg/mL, 0.0781 mg/mL, 1.250 mg/mL, and 0.625 mg/mL against the pathogenic mycobacterial strain, M. tb H37Rv (ATCC 27294), respectively.

Conclusions: S. torvum stem bark has demonstrated significant activity against the pathogenic M. tb strain. This observation validates the ethno-pharmacological use of the plant species against TB. Further studies are required to isolate, elucidate the structure, and characterize the antimycobacterial compounds responsible for the observed activity. These will potentially contribute toward bioprospecting for a new class of ligands with activity against sensitive and drug-resistant strains of M. tb.

Background: Tuberculosis (TB) caused by Mycobacterium tuberculosis complex remains a leading cause of morbidity and mortality worldwide. The zoonotic infectious condition represents a never-ending challenge toward which drug discovery efforts are needed. The current study was designed to evaluate the in vitro antimycobacterial activity of hydroethanolic extracts from Allium sativum and Allium cepa bulbs and leaves, traditionally used against respiratory tract illnesses, including TB.

Methods: The phenotypic colorimetric microplate Alamar blue assay was used to study the antimycobacterial activity of the ethanolic extracts against six mycobacterial strains. Each experiment was run in triplicate. Data generated were analyzed using descriptive statistics to obtain mean minimum inhibitory concentration (MIC) values.

Results: The A. sativum bulbs, A. sativum leaves, A. cepa bulbs, and A. cepa leaves exhibited MIC values of 19.5 µg/mL, 78.1 µg/mL, 78.1 µg/mL, and 19.5 µg/mL against the pathogenic mycobacterial strain, M. tuberculosis H37Rv (ATCC 27294), respectively.

Conclusion: In conclusion, the tested A. sativum and A. cepa bulbs and leaves have demonstrated significant activity against the pathogenic M. tuberculosis strain. This observation validates the ethnopharmacological use of the Allium species against TB. Further studies are required to isolate, elucidate the structure, and characterize the antimycobacterial compounds responsible for the observed activity. These will potentially contribute toward bioprospecting for a new class of ligands with activity against sensitive and drug-resistant strains of M. tuberculosis.

Background: Diagnostic delay among tuberculosis (TB) patients leads to late anti-TB treatment initiation, which is associated with poor prognosis and increased TB transmission. Despite its recognized negative consequences, diagnostic delay among TB patients is common in developing countries, including Afghanistan, where evidence on its predictors is limited. We aimed to evaluate diagnostic delay and its predictors among newly diagnosed TB patients attending healthcare facilities in Kandahar, Afghanistan.

Methods: A multicenter, cross-sectional study was conducted in Kandahar between February and May 2025. Newly diagnosed TB patients aged 18 years or older were randomly recruited from the TB care centers of six healthcare facilities. Delays in TB diagnosis encompassed both patient and healthcare system delays. The predictors of diagnostic delay were identified using a multivariable logistic regression model.

Results: Patient and health system delays were noted in 44% and 59.4% of cases, respectively. Patients' low education level, extrapulmonary TB, longer distance to healthcare facility, and positive history of self-medication were significant predictors of diagnostic delays.

Conclusion: Despite the well-established benefits of early TB diagnosis, this study revealed that delay in TB diagnosis is still a public health challenge in Kandahar province. Late presentation for TB care was a result of factors that relate to the patient's education, TB type, distance to healthcare facility, and history of self-medication. Therefore, focusing extra attention on these factors could potentially reduce diagnostic delays among TB patients in Afghanistan.

Background: Tuberculosis (TB) remains a significant global health challenge, causing 1.3 million deaths in 2020. The COVID-19 pandemic has further exacerbated the TB burden, leading to an 11% rise in TB mortality in India from 2019 to 2020. The World Health Organization aims to reduce TB deaths by 90% by 2030 and 95% by 2035. Early identification and management of severely ill TB patients are crucial for achieving these targets. This study aimed to identify adult TB patients at high risk of severe illness (HRSI) using a programmatic screening tool, assess referral linkages, and evaluate care outcomes within the first 7 days post-diagnosis in Bengaluru, India.

Methods: A cross-sectional study was conducted over 18 months (August 2022 to July 2023) across five Tuberculosis Units in the Bruhat Bengaluru Mahanagara Palike district. Data were collected from National Tuberculosis Elimination Program records and patient interviews, including 263 adult drug-sensitive TB patients diagnosed at public health facilities. Patients were screened for HRSI within 7 days of diagnosis using a tool assessing body mass index (BMI), respiratory rate, and oxygen saturation. Descriptive statistics summarized patient characteristics and outcomes, and associations were analyzed using Chi-square and Fisher's exact tests.

Results: Of the 263 TB patients screened, 20.9% were identified as being at HRSI. Among these high-risk patients, 73.3% accessed inpatient care, with 51% seeking treatment at district hospitals and 20% at private hospitals. Inpatient mortality among high-risk patients was 19.4%, while no deaths were reported among those managed as outpatients. Key severity indicators included BMI ≤14 kg/m2 (12%), respiratory rate >24 breaths/min (3%), oxygen saturation <94% (7%), and inability to stand without support (8%). High-risk status was more prevalent among patients over 65 years of age, males, those with microbiologically confirmed or smear-positive pulmonary TB, HIV-reactive status, and diabetes mellitus.

Conclusion: Early identification and referral of TB patients at HRSI are essential to reduce mortality. The study highlights the effectiveness of a simple screening tool in routine programmatic settings and underscores the need for targeted interventions and improved healthcare access for high-risk TB patients in India.

Background: This study evaluates an enzyme-linked immunosorbent assay test for the detection of immunoglobulin G (IgG) antibody response using in-house prepared Mycobacterium tuberculosis H37Rv soluble extract (MTSE) antigen for rapid diagnosis of pulmonary tuberculosis (PTB).

Methods: A total of 758 PTB patients (652 acid-fast bacilli [AFB] positive and 106 AFB-negative), 276 healthy controls, and 43 pulmonary infectious disease controls other than TB were recruited. IgG antibody level against MTSE was measured in serum samples of all study groups. The level of IgG antibody responses was compared among groups by the Kruskal-Wallis test, and pairwise comparison was made by the Mann-Whitney test. A positive score was represented by optical density (OD) above the cutoff value, which was calculated from OD values of healthy controls by adding 2 standard deviations (SDs) to the mean OD value. The evaluation of diagnostic value was considered based on sensitivity and specificity.

Results: Significantly higher levels of IgG antibody response were observed in PTB patients compared to other groups (P < 0.0001). The percent positivity for the IgG antibody response was higher in AFB-positive 574/652 (88.04%) and 79/106 (74.53%) AFB-negative PTB patients as compared to healthy control 9/276 (3.26%) and non-TB other pulmonary infectious disease control 3/43 (6.97%). The sensitivity of the test in PTB patients (AFB-positive and AFB-negative) was 86.15% (95% confidence interval [CI]: 83.48-88.53), and the specificity was 96.74% (95% CI: 93.90-98.50).

Conclusion: This immunological test could be an efficient test in detecting IgG antibody response in PTB patients and could be useful for diagnosing AFB-negative presumptive TB cases.

Mycobacterium marinum is slow-growing mycobacteria, a common atypical mycobacteria that causes opportunistic infections in humans and is capable of causing disease in the skin and soft tissues. This cutaneous disorder has a wide clinical spectrum with cutaneous inflammation and granulomatous nodules that can spread along with the distribution of the lymphatic system. The infection predominantly affects the extremities. The accurate diagnosis is often challenging, requiring the presence of bacteria at the lesion. Conventional treatment usually requires a combination of antibiotics and long-term use. To report a case of M. marinum infection successfully treated with ethambutol and clarithromycin, we present a 71-year-old male patient who lives in the coastal area developed purulent hand inflammation and many subcutaneous nodular lesions. The diagnosis was based on the analysis of hand nodules using histopathology, Ziehl-Neelsen staining, and polymerase chain reaction. This positive outcome gives insight into a rare skin infection in Vietnam and strengthens suggested treatment guidelines.

We report a rare case of vertebral osteomyelitis due to Mycobacterium farcinogenes in a patient who had undergone left-sided percutaneous nephrolithotomy for renal stones. Following the procedure, he developed a wound site infection that progressed to vertebral osteomyelitis and a paravertebral abscess. Initial treatment with empirical anti-tubercular drugs was ineffective. A computed tomography-guided aspiration and biopsy identified acid-fast bacilli as M. farcinogenes using Matrix-assisted laser desorption ionization-time-of-flight. Treatment was then tailored based on the susceptibility results, leading to a positive response.

Caseum, the central necrotic material of tuberculous lesions, is a reservoir of drug-resistant persisting Mycobacterium tuberculosis (MTB). However, tubercle bacilli are not the only bacterial inhabitants of this necrosis. We discuss the available data on metagenomic and amplicon sequencing of 16S rRNA of caseous necrosis from surgically excised tuberculosis (TB) foci. This approach facilitated the characterization of the biodiversity and the potential biochemical pathways of these bacterial communities. We postulate that in terms of MTB content relative to satellite anaerobic lipophilic bacteria, caseum may present two distinct terminal states. "True" TB necrosis, containing 99.9% tubercle bacilli, and a polymicrobial community wherein anaerobic lipophilic bacteria predominate over MTB. Isolation from caseum and genomic characterization of several Corynebacterium and Staphylococcus species support this concept.