International Journal of Mycobacteriology最新文献

Endophthalmitis is a severe intraocular infection that poses a substantial risk of permanent vision loss if not promptly diagnosed and treated. Among its diverse etiologies, infections caused by Mycobacterium species are notably rare yet clinically significant due to their slow-growing nature and atypical presentations, which complicate diagnosis and management. This systematic review examines the role of Mycobacterium species in cases of endophthalmitis, with a particular focus on their etiologies and diagnostic challenges. A comprehensive search of electronic databases yielded 14 studies published between 2014 and 2024, providing insights into the identification and characterization of these pathogens in intraocular infections. The findings highlight the importance of heightened clinical suspicion and the use of advanced microbiological techniques to detect Mycobacterium species, given their subtle clinical manifestations and prolonged culture requirements. Addressing these challenges is critical for timely intervention and optimizing patient outcomes. This review underscores the need for further research to establish standardized diagnostic protocols and effective treatment strategies for Mycobacterium-associated endophthalmitis. Such efforts will enhance understanding of these rare but impactful infections, ultimately contributing to improved clinical management and preservation of vision.

Tuberculosis (TB) is a significant global health issue with India accounting for about 25% of the global TB burden. While TB primarily impacts the lungs, extrapulmonary cases are also common, particularly female genital TB (GTB) among younger patients accounting for about 10%-15% of all TB infections. Isolated ovarian TB is a very rare form of extrapulmonary TB that usually presents with atypical symptoms. It presents a diagnostic challenge pertaining to its clinical presentation which is often misleading and mimics ovarian malignancy. Even though TB is curable and preventable, GTB poses a significant risk of infertility in women of reproductive age highlighting the need of screening in areas with a high prevalence of TB.

Disseminated tuberculosis (dTB) is usually rare in immunocompetent individuals. We report a case of dTB presented with constitutional symptoms and extensive lymphadenopathy with bilateral lung parenchymal airspace opacities. Histopathological and molecular methods confirmed the etiological agent - Mycobacterium tuberculosis. She was started on first-line antitubercular treatment and she had significant clinical recovery.

Background: Pulmonary tuberculosis (TB) is predominantly caused by Mycobacterium tuberculosis complex (MTBC) and can also involve nontuberculous mycobacteria (NTM). These pathogens pose significant global health challenges, particularly in developing countries. Differentiating between MTBC and NTM in clinical specimens is often difficult using conventional acid-fast staining methods, leading to an underestimation of NTM prevalence in TB-endemic regions. This study aims to identify mycobacterial species in sputum samples from patients suspected of having TB, utilizing polymerase chain reaction (PCR) assays and gene sequencing techniques.

Methods: We collected 111 sputum samples from patients at Dr. Wahidin Sudirohusodo Central General Hospital, Hasanuddin University Hospital, and Makassar Community Lung Health Center. The samples were analyzed at the Clinical Microbiology Laboratory of Hasanuddin University using standard microscopy and molecular detection techniques. Descriptive statistics were employed to summarize patient demographics, infection characteristics, and outcomes.

Results: We collected sputum from suspected TB patients with an average age of 50.86 years. We found 16.2% (n = 18) acid-fast bacteria in 111 patients with suspected pulmonary TB, and molecularly, we identified 17.1% (n = 19) Mycobacterium species by multiplex PCR. Three sputum samples tested positive for NTM. Phylogenetic analysis, based on 16S rRNA gene sequencing, revealed similarities between the samples and known mycobacterial species.

Conclusions: The study underscores the challenges in differentiating between MTBC and NTM, highlighting the necessity for molecular diagnostic approaches. Notably, we found NTM in sputum samples from patients previously treated for TB. These findings can serve as a reference for improving diagnostic accuracy and preventing misdiagnosis of mycobacterial infections.

Miliary tuberculosis (TB) is an uncommon yet severe condition that can pose substantial risks to pregnant women and their unborn child. This case study describes a 22-year-old pregnant female at 23 weeks of gestation presented with breathlessness, fever accompanied by chills, dry cough, and loss of appetite. With no significant comorbidities, her initial symptoms were inconclusive, leading to her initial diagnosis as a case of pyrexia of unknown origin. Despite receiving iron supplements for anemia and broad-spectrum antibiotics, her health continued to decline, prompting her transfer to a specialized medical center where advanced molecular testing ultimately confirmed a diagnosis of miliary TB. Upon admission, she was promptly started on anti-TB therapy and managed in the intensive care unit, where her clinical course included the development of acute respiratory distress syndrome (ARDS) requiring ventilatory support. Through meticulous monitoring and multidisciplinary intervention, the patient stabilized and ultimately delivered a healthy baby girl through normal vaginal delivery. Miliary TB, though rare, is challenging to diagnose during pregnancy due to overlapping symptoms with other conditions. This case underscores the critical importance of recognizing the atypical presentations of miliary TB in pregnant women, particularly in the context of previous exposure. It highlights the need for high clinical suspicion, timely diagnosis, and comprehensive management strategies to ensure favorable outcomes for both mother and child in the face of such challenging clinical scenarios.

This review examines the impact of F420 biosynthesis protein C (fbiC) mutations in Mycobacterium tuberculosis (Mtb) and their influence on the bacterium's dormancy mechanisms. The potential role of fbiC mutations and functional impairments in the persistence of Mtb is emphasized. Tuberculosis (TB) bacilli can enter a dormant state with minimal metabolic activity, allowing them to conserve resources and survive in low-nutrient, low-oxygen environments for extended periods. While the fbiC gene contributes to dormancy, Mtb can achieve this state through multiple genetic and metabolic pathways, suggesting that it may still undergo dormancy even with functional impairments in fbiC. In this review, we utilized several scientific databases, including PubMed, Web of Science, and Google Scholar, and set of key search terms including "fbiC gene," "F420 Biosynthesis," "Mycobacterium tuberculosis," "Dormancy," and "Drug Resistance" to highlight the significance of the fbiC gene in regulating dormancy and explore how Mtb compensates for fbiC dysfunction through various metabolic adaptations.

Background: Extrapulmonary tuberculosis (EP-TB) constitutes one-fifth of all tuberculosis (TB) cases. EP-TB mimics common infections which pose diagnostic dilemma, requires extensive diagnostics that culminate into therapeutic delay often resulting in irrational and empirical institution of antitubercular therapy (ATT) in challenging cases. This supplemented by poor treatment compliance resulted in emergence of Drug-resistant (DR) strains of EP-TB which further impedes the path to recovery. The aim of the present series is to study the rare and diverse presentations of EP-TB caused by drug-sensitive (DS) and DR mycobacterium that require a multi-modal diagnostic approach and appropriate treatment.

Methods: This observational retrospective series incorporated six rare EP-TB cases, excluding those with solitary lung affection and underwent comprehensive diagnostic tests aimed at microbial isolation from affected tissues with subsequent drug resistance testing. They were treated by integrative approach, standard (first/second/third line) ATT while few required emergent surgical interventions. Patient outcomes were evaluated based on clinicoradiological improvement and microbiological clearance determined in follow-up.

Results: Out of six cases (four males and two females; age range: 14-62 years), pleural linings, kidneys, brain and its lining, skin, and axial skeleton were directly affected, while superior mesenteric artery (SMA) syndrome was an indirect consequence of infection. Elective thoracic and urosurgical interventions supplemented medical management in two cases while urgent neurosurgical decompression improved outcomes in Pott's spine case that exhibited drug resistance. Notably of five DS EP-TB, one patient showed poor clinical response necessitating treatment escalation while nutritional rehabilitation was key in SMA syndrome.

Conclusions: EP-TB requires high clinical suspicion and a multidisciplinary approach for diagnosis and treatment. Addressing treatment adherence, with emphasis on good nutrition to tackle cachexia, is necessary for favorable outcomes.

Background: Tuberculosis (TB), caused by Mycobacterium tuberculosis (MTB), can enter a dormant phase within host tissues, complicating treatment and highlighting the need to investigate the genetic changes associated with dormancy.

Methods: This study examined clinical isolates of MTB, representing a range of susceptibility profiles and standard reference laboratory strains, i.e., H37Rv and Mycobacterium bovis bacillus Calmette-Guérin. Each strain was subcultured in a controlled laboratory environment to analyze two distinct phases: one maintained in vitro under a double-stress dormancy model using the Wayne model (characterized by the absence of oxygen and nutrients) for 12 months, and the other examined during its exponential growth phase. Whole-genome sequencing and protein structure analysis using bioinformatics tools were performed to characterize and compare mutations in isolates at each phase.

Results: Three distinct frameshift mutations were identified in the fbiC, PPE35, and ald genes, and one upstream mutation in whiB6 genes in all studied isolates under dormancy, irrespective of their susceptibility patterns (P < 0.01). Among drug-resistant strains, at the exponential phase isolated from patients with prolonged treatment, 5%-7% had PPE35, ald mutations, whereas 95% had the whiB6 mutation, suggesting that adaptive stress responses may be triggered under in vivo conditions.

Conclusions: The newly identified frameshift mutations (fbiC, PPE35, and ald genes), consistently found in both laboratory and clinical isolates, seem to play a critical role in the survival of MTB during dormancy. Based on these findings, designing a molecular test to differentiate between active and latent TB possibly enables timely prophylactic interventions.

Background: In Morocco, latent tuberculosis infection (LTBI) is a public health concern affected by the country's location as transit area between sub-Saharan Africa with high TB burden to Europe. This study aimed to assess the influence of exposure intensity to Mycobacterium tuberculosis (Mtb), age, and Bacille Calmette-Guérin (BCG) vaccination on LTBI prevalence in Morocco.

Methods: A cross-sectional study of 131 participants, including 98 non-exposed healthy volunteers (NEHV) and 33 healthcare workers exposed to active TB (exposed healthcare workers [EHCW]), was conducted. The Interferon-γ Release Assay (IGRA) was used to detect LTBI, and results were analyzed according to participants' age and BCG vaccination status.

Results: EHCW showed a higher prevalence of LTBI than NEHV (36.7% vs. 57.6%) and of EHCW were positive for LTBI. In both groups, the mean age of those with LTBI was higher than those without. Furthermore, we showed within both groups, that LTBI prevalence was positively associated with subjects less covered by BCG vaccination in comparison with subjects likely totally covered by this vaccination (adjusted odds ratio [aOR], 2.783; 95% confidence intervals [CI], 1.180-6.57; P = 0, 01), (aOR, 6.717; 95% CI, 1.254-35.977; P = 0.02).

Conclusion: Our results showed that in the Moroccan TB epidemic context, the prevalence of LTBI still lower among healthy adults general population than within EHCW. Furthermore, this LTBI showed to be positively impacted by age in the two condition of exposure. We also showed that BCG vaccination seems to affect the prevalence of LTBI within both high and low intensity of exposure to Mtb infection.

Background: Tuberculosis (TB) caused by Mycobacterium tuberculosis is an infectious disease affecting mainly the lungs and persists as the leading cause of death worldwide. With the emergence of coronavirus disease-19 (COVID-19) pandemic, the management and outcome of TB has been greatly affected because of the global shift in attention. This study aims to determine the effects of COVID-19 pandemic on the TB treatment uptake and outcomes in the Fako Division of Cameroon.

Methods: A hospital-based retrospective and cross-sectional study was carried out in 3 Health Districts of the Fako Division of Cameroon. Extraction forms and structured questionnaire were used to collect both quantitative and qualitative data from records and health personnel, respectively. Data on treatment uptake and outcomes before and during the pandemic were compared, as well as challenges faced in TB diagnosis and treatment during the pandemic.

Results: Of the 1557 reviewed files of TB patients, treatment uptake was lower (73.40%) during compared to before (82.30%) the pandemic (P < 0.0001). A larger proportion (83.30%) had a successful outcome before compared to (74.3%) during the pandemic (P < 0.0001). There was a significant drop in both good TB treatment uptake (8.9%) and successful outcomes (9%), respectively, during the pandemic. A number of significant challenges faced in TB diagnosis and treatment during the pandemic included shortage of drugs (63.6%) and diagnostic materials (54.5%), as well as decrease in the diagnosis rate of TB patients (90.9%) with the main reason being fear of being quarantined at the hospital (63.6%).

Conclusions: A decrease in TB treatment uptake and successful outcomes was observed during the COVID-19 period compared to prior the pandemic. This is indicative of poor usage of the TB services during the pandemic as a result of COVID-19 barrier measures and laxity in the TB control programs. TB programs require some intensification geared towards strengthening the patient-centered approach and a community-based active TB case finding, especially in the current potential resurgence of the pandemic.