Mycobacterium Tuberculosis in Spinal Tuberculosis

Intercepting a Mycobacterial Biosynthetic Pathway with Covalent Labeling

The mycobacterial cell envelope plays both infectious and protective roles. Understanding its structure is crucial for unlocking the molecular basis underlying these functions. Studying glycans, the primary components of the cell envelope, is challenging due to their limited native functional handles for chemoselective modification. New labeling methods exploit biorthogonal chemistry, using small molecule mimics that intercept cellular metabolism or late-stage glycan biosynthesis. However, these strategies can have practical limitations, including probe delivery and effectiveness. An ideal small molecule probe should be easily deployed and exploit the critical enzyme-substrate relationships of natural substrates. To this end, we developed a "probegenic" strategy to label mycobacteria. Our approach eliminates the need for explicit substrate mimicry, as the relevant functionality is revealed by a target enzyme. Specifically, we synthesized an azide-substituted trans-β-lactone probe (AzLac), which adopts a substrate-like structure upon covalent enzyme labeling. This probe is incorporated by mycolyltransferases into a core mycobacterial cell envelope glycan, including in the pathogen Mycobacterium tuberculosis. Unlike other probes of the cell envelope, AzLac facilitates selective covalent labeling of the inner leaflet of the mycomembrane. Using Corynebacterium glutamicum mycolyltransferase deletion strains, we implicated Cmt2 as the primary mycolyltransferase target. We leveraged the ability to modify the cell envelope by demonstrating that AzLac could be used to attach a DNA barcode to mycobacteria, which would help track infection dynamics. Thus, we expect AzLac will be a valuable means of monitoring and tracking the mycobacterial cell envelope. Moreover, we anticipate masking and revealing recognition motifs in probes can be applied to diverse cellular targets.

Exploring the Chemical Space of Mycobacterial Oxidative Phosphorylation Inhibitors Using Molecular Modeling

Mycobacteria are opportunistic intracellular pathogens that have plagued humans and other animals throughout history and still are today. They manipulate and hijack phagocytic cells of immune systems, enabling them to occupy this peculiar infection niche. Mycobacteria exploit a plethora of mechanisms to resist antimicrobials (e. g., waxy cell walls, efflux pumps, target modification, biofilms, etc.) thereby evolving into superbugs, such as extensively drug-resistant tuberculosis (XDR TB) bacilli and the emerging pathogenic Mycobacterium abscessus complex. This review summarizes the mechanisms of action of some of the surging antimycobacterial strategies. Exploiting the fact that mycobacteria are obligate aerobes and the differences between their oxidative phosphorylation pathways versus their human counterpart opens a promising avenue for drug discovery. The polymorphism of respiratory complexes across mycobacterial pathogens imposes challenges on the repositioning of antimycobacterial agents to battle the rise in nontuberculous mycobacterial infections. In silico strategies exploiting mycobacterial respiratory machinery data to design novel therapeutic agents are touched upon. The potential druggability of mycobacterial respiratory elements is reviewed. Future research addressing the health challenges associated with mycobacterial pathogens is discussed.

The rabbit model for spinal tuberculosis: An overview

Mycobacterium tuberculosis infection has emerged as a global public health issue, predominantly manifesting as pulmonary tuberculosis. Bone and joint tuberculosis, with spinal tuberculosis accounting for approximately 50%, represents a significant form of extrapulmonary tuberculosis. Over the past years, there has been a rise in the incidence of spinal tuberculosis, and research concerning this area has gained significant attention. At present, animal models provide a means to investigate the pathogenesis, drug resistance, and novel treatment approaches for spinal tuberculosis. New Zealand rabbits, possessing a comparable anatomical structure to humans and capable of reproducing typical pathological features of human tuberculosis, are extensively employed in spinal tuberculosis research using animal models. This article comprehensively evaluates the strengths, considerations in strain selection, various modelling approaches, and practical applications of the rabbit model in studying spinal tuberculosis based on pertinent literature to guide fundamental research in this field by providing valuable insights into appropriate animal model selection.

Rapid and Ultrasensitive Approach for the Simultaneous Detection of Multilocus Mutations to Distinguish Rifampicin-Resistant Mycobacterium tuberculosis

The untested empirical medications exacerbated the development of multidrug-resistant Mycobacterium tuberculosis (MDR-TB). Here, we develop a rapid and specific method based on loop-mediated isothermal amplification and duplex-specific nuclease for distinguishing rifampicin-resistant M. tuberculosis. Three probes were designed for the codons 516, 526, and 531 on the RNA polymerase β-subunit (rpoB) gene. These three sites accounted for more than 90% of the total mutations of the ropB gene in the rifampicin-resistant strain. The approach can perform simultaneous and sensitive detection of three mutant sites with the actual detection limit as 10 aM of DNA and 62.5 cfu·mL^-1 of bacteria in 67 min under isothermal conditions. Moreover, the positive mode of the approach for MDR-TB can not only deal with the randomness and diversity of mutations but also provide an easier way for medical staff to read the results. Therefore, it is a particularly valuable method to handle major and urgent MDR-TB diagnostics.

Tuberculous Granuloma: Emerging Insights From Proteomics and Metabolomics

Mycobacterium tuberculosis infection, which claims hundreds of thousands of lives each year, is typically characterized by the formation of tuberculous granulomas — the histopathological hallmark of tuberculosis (TB). Our knowledge of granulomas, which comprise a biologically diverse body of pro- and anti-inflammatory cells from the host immune responses, is based mainly upon examination of lungs, in both human and animal studies, but little on their counterparts from other organs of the TB patient such as the brain. The biological heterogeneity of TB granulomas has led to their diverse, relatively uncoordinated, categorization, which is summarized here. However, there is a pressing need to elucidate more fully the phenotype of the granulomas from infected patients. Newly emerging studies at the protein (proteomics) and metabolite (metabolomics) levels have the potential to achieve this. In this review we summarize the diverse nature of TB granulomas based upon the literature, and amplify these accounts by reporting on the relatively few, emerging proteomics and metabolomics studies on TB granulomas. Metabolites (for example, trimethylamine-oxide) and proteins (such as the peptide PKAp) associated with TB granulomas, and knowledge of their localizations, help us to understand the resultant phenotype. Nevertheless, more multidisciplinary ‘omics studies, especially in human subjects, are required to contribute toward ushering in a new era of understanding of TB granulomas – both at the site of infection, and on a systemic level.

A Scoring System for Outpatient Orthopedist to Preliminarily Distinguish Spinal Metastasis from Spinal Tuberculosis: A Retrospective Analysis of 141 Patients

Objective

Spinal tuberculosis (TB) misdiagnosed of spinal metastasis was not rarely reported, especially in outpatients department. This study was aimed to establish an outpatient scoring system to preliminarily distinguish spinal metastasis from spinal TB.

Methods

We retrospectively reviewed consecutive 141 patients with a pathological diagnosis of spinal metastasis (82 cases) or spinal TB (59 cases) in our hospital from January 2017 to June 2018. The following clinical characteristics which can be obtained by outpatient orthopedist were recorded and analyzed: age, gender, malignant tumor history, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and imaging features including distribution characteristics of vertebral lesions, subligamentous spread, paravertebral or psoas abscess, involved vertebral element, intervertebral disc, and sequestra formation. The prevalence of clinical characteristics in spinal metastasis was evaluated, and the scoring system was established using logistic regression analysis. The performance of the scoring system was also prospectively validated.

Results

The outpatient scoring system was based on five clinical characteristics confirmed as significant predictors of spinal metastasis, namely, malignant tumor history, subligamentous spread, posterior element lesions, preserved discs, and no sequestra formation. Spinal metastasis showed a significant higher score than spinal TB (8.17 points vs. 1.97 points, t = 18.621, P < 0.001), and the optimal cut-off value for the scoring system was 5 points. The sensitivity and specificity of the scoring system for predicting spinal metastasis were 97.85% and 88.33%, respectively, in the validation set.

Conclusion

Spinal lesions with the score of 5 to 10 would be considered a diagnosis of spinal metastasis, while the score of 0 to 4 may be spinal TB. Because the scoring system is mainly based on the clinical characteristics that can be obtained by an outpatient orthopedist, it is suitable to be used as a diagnostic tool in the outpatient department.

Is spinal tuberculosis changing with changing time?

Introduction

Spinal tuberculosis is a chronic destructive disease with long-term morbidity. Patients are usually young especially from a poor socioeconomic background. Destruction of the intervertebral disk space and the adjacent vertebral bodies is the characteristic lesion. The dorsal spine is the most affected region with multi-level noncontiguous involvement being detected more frequently. Patients usually present with chronic back pain associated with spinal tenderness, paraplegia, spinal deformities, as well as with constitutional symptoms. Magnetic resonance imaging has proved to be more sensitive and specific for its diagnosis, but availability and affordability of this investigation remain a problem in developing countries. Anti-tuberculous drug therapy has revolutionized the treatment of this debilitating disease. Surgery is still required in selected cases especially with evolving neurological deficit, progressive deformity, intractable pain and lack of response to drug therapy. With early diagnosis and effective treatment, prognosis is generally good.

Materials/Methods: After getting permission from the clinical governance department, We collected the retrospective data of 305 patients with diagnosed spinal tuberculosis, who underwent surgical intervention.

Results

There was no significant difference in incidence among males and females. Housewives were the most affected. Lower dorsal spinal was the commonest site involved but our study didn't confirm the incidence of multi-level disease process. Anterior decompression along with Cage fixation was most frequently performed procedure.

Conclusion

Despite the availability of highly effective antituberculous drugs, advanced surgical procedure, the spinal tuberculosis still maintains its demographic profile. There has been no change in characteristics of spinal presentation of this chronic debilitating disease. Patients continue to suffer the same way as they were suffering decades ago.

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Spinal tuberculosis is a chronic destructive disease with long-term morbidity.

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The dorsal spine is the most affected region with multi-level involvement being detected.

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Analysis of data of 305 patients with diagnosed spinal tuberculosis, who underwent surgical intervention.

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Despite the availability of highly effective drugs, and surgical procedure, the spinal tuberculosis still maintains its demographic profile.

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There has been no change in characteristics of spinal presentation of this chronic debilitating disease.

Diagnostic values of peripheral blood T-cell spot of tuberculosis assay (T-SPOT.TB) and magnetic resonance imaging for osteoarticular tuberculosis: a case-control study

OBJECTIVE

Early diagnosis of osteoarticular tuberculosis helps improve patients' outcomes, but little is known about the accuracy of noninvasive diagnostic methods. This case-control study aimed to assess the diagnostic value of peripheral blood T-cell spot of tuberculosis assay (T-SPOT.TB) and magnetic resonance imaging (MRI).

METHODS

Patients suspected with osteoarticular tuberculosis were retrospectively included and diagnosed according to the composite reference standard. T-SPOT.TB was used to detect the number of cells secreting Interferon gamma. Diagnostic performance of T-SPOT.TB and MRI alone and combined were evaluated.

RESULTS

Among the suspected patients, 92 had osteoarticular tuberculosis and 137 non- osteoarticular tuberculosis. T-SPOT.TB assay alone had a higher sensitivity (0.73 vs. 0.60) but a lower specificity (0.69 vs. 0.91 P>0.05) in diagnosing osteoarticular tuberculosis. Combined serial test showed a sensitivity and specificity 0.47, 0.97, respectively, whereas combined parallel test showed a sensitivity and specificity of 0.86, 0.65, respectively. Specificity was higher in the combined serial test than in the T-SPOT.TB assay (P=0.007) or MRI alone (P < 0.001). Furthermore, sensitivity was higher in the combined parallel test than in the T-SPOT.TB assay (P < 0.001) or MRI alone (P < 0.001).

CONCLUSIONS

Combined blood T-cell spot of tuberculosis assay and osteoarticular MRI have higher sensitivity and specificity for noninvasive osteoarticular tuberculosis diagnosis, compared with either method alone.

Diagnosis of Osteoarticular Tuberculosis: Perceptions, Protocols, Practices, and Priorities in the Endemic and Non-Endemic Areas of the World-A WAIOT View

There has been a major resurgence of tuberculosis (TB) and drug-resistant tuberculosis in the last few decades. Although it has been brought under control in most Western countries, it is still a major cause of death in endemic regions like India. Osteoarticular tuberculosis (OA TB) forms a small proportion of the total cases of tuberculosis. Perceptions and practices of orthopedic surgeons are entirely different in endemic and non-endemic regions around the world, due to the vast difference in exposure. Literature from endemic areas puts stress on clinico-radiological diagnosis and empirical anti-tubercular treatment (ATT). Such practices, although non-invasive, simple to implement, and economical, carry a significant risk of missing TB mimics and developing drug resistance. However, OA TB is still perceived as a “diagnostic enigma” in non-endemic regions, leading to a delay in diagnosis. Hence, a high index of suspicion, especially in a high-risk population, is needed to improve the diagnosis. Evolving drug resistance continues to thwart efforts to control the disease globally. This review article discusses the perceptions and practices in different parts of the world, with India as an example of the endemic world, and lays down priorities for overcoming the challenges of diagnosing osteoarticular TB.

Characteristics and Management of Spinal Tuberculosis in Tuberculosis Endemic Area of Guizhou Province: A Retrospective Study of 597 Patients in a Teaching Hospital

Background

Tuberculosis (TB) is an endemic disease in Guizhou. Spinal TB accounts for approximately 50% cases of skeletal TB. The purpose of this study was to investigate the characteristics and management of patients treated for spinal TB in a certain hospital and to provide guidance for the prevention and treatment of spinal TB.

Methods

The clinic records of all patients diagnosed with spinal tuberculosis in a teaching hospital between January 2010 and December 2018 were collected. The epidemiology, clinical characteristics, imaging and laboratory findings, treatment methods, and prognosis were recorded and analyzed.

Results

During this nine-year period, 597 patients with spinal TB were identified. There were 313 males and 284 females with an average age of 43 years. The largest number of patients fell in the age group of 21–30 years; mean time from symptom onset to diagnosis in the hospital was 17 months. Back pain was the main clinical manifestation (89.34%). The most common imaging technique was computed tomography (CT, 96.80%), followed by magnetic resonance imaging (MRI, 84.01%). Majority of the lesions involved the lumbar spine (47.30%), followed by the thoracic spine (40.95%). 178 (29.82%) patients in this study had varying degrees of neurological impairment. 22.78% of the patients selected conservative treatment, and surgical treatment was performed in 483 patients (80.90%).

Conclusions

The incidence of spinal TB was generally on the rise throughout the study period. After diagnosed with spinal TB, all patients got appropriate treatment and achieved good efficacy, but most of the patients did not pay much attention to the disease and receive timely treatment. Thus, it is essential to strengthen the TB preventive strategies, improve the health awareness of residents and universal resident health examination.

Essential Basic Bacteriology in Managing Musculoarticuloskeletal Infection: Bacterial Anatomy, Their Behavior, Host Phagocytic Activity, Immune System, Nutrition, And Antibiotics

Surgery-related infections have not been irradicated until now. To solve this problem, it is important to know the relationship between bacterial anatomy and bacterial behavior in the tug-of-war between host and pathogen. In this article, bacterial anatomy and functional behavior, host phagocytic activity, immune system, nutrition and antibiotics are reviewed to win the war against the tiny invaders and leave the host unharmed. My suggestion is that scientists should direct their studies not only to developing potent new antibiotics that will never give rise to drug-resistant mutants, but also to developing a very competitive immune system that can suppress or control infection without the aid of antibiotics.

Correlation between MBL2/CD14/TNF-α gene polymorphisms and susceptibility to spinal tuberculosis in Chinese population

Objective: The present study investigated the clinical significance of mannose-binding lectin 2 (MBL2), cluster of differentiation 14 (CD14) and tumour necrosis factor-α (TNF-α) gene polymorphisms in patients with spinal tuberculosis (TB) in Chinese population. Methods: A total of 240 patients with spinal TB were enrolled in the present study from May 2013 to August 2016 at Hangzhou Red Cross Hospital. A total of 150 age- and sex-matched healthy subjects were enrolled as controls. The genomic DNA was extracted from the peripheral blood of all subjects, and the MBL2, CD14 and TNF-α gene polymorphisms were detected by direct DNA sequencing. Results: (1) Compared with controls, patients with spinal TB exhibited a significantly higher frequency of the XY genotype at the −221G>C polymorphism as well as the Q allele and PQ genotype or an association with the QQ genotype at the +4C>T polymorphism in the MBL2 gene. (2) Compared with controls, patients with spinal TB exhibited a significantly higher frequency of the T allele and TT genotype or an association with the CT genotype at the −159C>T polymorphism in the CD14 gene. (3) Compared with controls, patients with spinal TB exhibited a significantly higher frequency of the T allele and the CT genotype or an association with the TT genotype at the TNF-857 polymorphism in the TNF-α gene. Conclusion: The −221G>C polymorphism of MBL2, the −159C>T polymorphism of CD14 and the TNF-857 polymorphism of TNF-α are risk factors for spinal TB and may be involved in the development of spinal TB in the Chinese population. These factors are indicators of susceptibility to spinal TB and require clinical attention.

Pancreatic Tuberculosis with Vascular Involvement and Peritoneal Dissemination in a Young Man

Pancreatic tuberculosis (TB) is an extremely rare form of extrapulmonary tuberculosis even in endemic areas that masquerades as a mass or inflammation because of lack of typical clinical manifestations and radiologic features and therefore usually misdiagnosed as a pancreatic malignancy or pancreatitis. Here we present a 23-year-old young man with pancreatic tuberculosis mimicking pancreatic head carcinoma A man who suffered from upper abdominal pain and nausea for half a month was admitted to our hospital. Narrow band imaging (NBI) and gastroscopic imaging, together with endoscopic ultrasonography (EUS), revealed a duodenal bulb mucous prominences lesion. Computed tomography (CT) and magnetic resonance imaging (MRI) both suggested a pancreatic mass which resembled a pancreatic head tumor that had a higher risk of malignancy. The patient therefore accepted an exploratory laparotomy and pancreatoduodenectomy, Whipple operation. Biopsies of pancreas, duodenum, lymph nodes, omentum, and adipose tissues were all performed, revealing tuberculosis infection in pancreas, hepatic portal vein infiltration, and peritoneal dissemination. The patient was treated successfully after operation and recovered with standard anti-TB drugs for 6 months. Timely reporting of this rare case can help physicians improve their ability to identify several specific illnesses and diseases that share confusing signs or symptoms clinically and radiographically.