Imaging in tuberculosis

Pediatric Meningeal Diseases: What Radiologists Need to Know

Evaluating altered mental status and suspected meningeal disorders in children often begins with imaging, typically before a lumbar puncture. The challenge is that meningeal enhancement is a common finding across a range of pathologies, making diagnosis complex. This review proposes a categorization of meningeal diseases based on their predominant imaging characteristics. It includes a detailed description of the clinical and imaging features of various conditions that lead to leptomeningeal or pachymeningeal enhancement in children and adolescents. These conditions encompass infectious meningitis (viral, bacterial, tuberculous, algal, and fungal), autoimmune diseases (such as anti-MOG demyelination, neurosarcoidosis, Guillain-Barré syndrome, idiopathic hypertrophic pachymeningitis, and NMDA-related encephalitis), primary and secondary tumors (including diffuse glioneuronal tumor of childhood, primary CNS rhabdomyosarcoma, primary CNS tumoral metastasis, extracranial tumor metastasis, and lymphoma), tumor-like diseases (Langerhans cell histiocytosis and ALK-positive histiocytosis), vascular causes (such as pial angiomatosis, ANCA-related vasculitis, and Moyamoya disease), and other disorders like spontaneous intracranial hypotension and posterior reversible encephalopathy syndrome. Despite the nonspecific nature of imaging findings associated with meningeal lesions, narrowing down the differential diagnoses is crucial, as each condition requires a tailored and specific treatment approach.

Assessment of radiological capacity and disparities in TB diagnosis: a comparative study of Mozambique, South Africa and Spain

Background

Tuberculosis (TB) remains a significant global health challenge, particularly in children, where diagnosis is challenging. Radiological resources such as chest X-rays and CT scans play a crucial role in early screening and diagnosis, especially in the absence of microbiological confirmation of disease. However, radiological capacity and access vary widely across regions and countries.

Methods

This study retrospectively audited licensed X-ray and CT units in Mozambique, South Africa and Spain in 2022. Population data were used to calculate units per million people. The study used choropleth maps to visualise regional disparities and to explore potential interactions between radiological capacity, population density and TB notifications.

Results

Mozambique had the lowest radiological capacity, with 3.6 X-ray units and 0.4 CT units per million people, compared with South Africa's 34.2 X-ray units, 5.8 CT units and Spain's 811.5 X-ray units and 19.3 CT units. The private sector exhibited higher capacity than the public sector in all countries. Regional disparities were evident, particularly in Mozambique, highlighting urban-rural discrepancies and in-country inequalities.

Conclusion

This study underscores significant disparities in radiological capacity between low-income, middle-income and high-income countries, with economic factors playing a pivotal role. Addressing these disparities is crucial for improving TB and other disease diagnostic capabilities, particularly in resource-limited settings. Potential solutions include establishing dedicated national radio-diagnostic departments, developing national guidelines and integrating portable AI-powered X-ray or point-of-care ultrasonography technology. These findings provide valuable insights for policymakers and stakeholders to advocate for improved radiological resources and equitable healthcare access.

An Unexpected Turn: An Unusual Case of a Metastatic Ovarian Carcinoma Arising from a Colorectal Malignancy

Krukenberg tumors are very rare. Its origin is difficult to define especially if its gross features mimic a primary ovarian cancer. We present a case of a 24-year-old Filipino female patient with metastatic mucinous ovarian adenocarcinoma of colonic origin that mimicked primary ovarian cancer and genitourinary tuberculosis. Surgery was done and histopathology revealed that the cancer was a metastatic mucinous adenocarcinoma of colonic origin. This case highlights the importance of differentiating between benign and malignant ovarian lesions as well as distinction between primary and metastatic ovarian neoplasms. Radiological imaging has an evolving role in diagnosis of different cancers, which may be improved through better clinical correlation and developing meaningful differential diagnosis while advancing to a more strategized algorithm in the diagnostic approach.

Colliding Challenges: An Analysis of SARS-CoV-2 Infection in Patients with Pulmonary Tuberculosis versus SARS-CoV-2 Infection Alone

Background and Objectives: The concurrent occurrence of tuberculosis and COVID-19 coinfection poses significant clinical complexities, warranting a nuanced approach to diagnosis, management, and patient care. Materials and Methods: A retrospective, cross-sectional study was conducted on two groups: one comprising 32 patients with pulmonary TB (PTB) and COVID-19 co-infection, and one including 100 patients with COVID-19 alone. Data was collected from medical records, including patient history, clinical parameters, laboratory, imaging results, and patient outcome. Results: A lower BMI emerges as a significant marker suggesting underlying PTB in patients with SARS-CoV-2 co-infection. Type 2 diabetes mellitus increases the risk of death in PTB-SARS-CoV-2 co-infection. Co-infected patients show lymphocytopenia and higher neutrophil levels, CRP, transaminases, and D-dimer levels. Elevated CRP and ALT levels are linked to increased co-infection likelihood. Certain parameters like SpO2, CRP, ALT, AST, and D-dimer effectively differentiate between co-infected and COVID-19 patients. Platelet-to-lymphocyte ratio is notably higher in co-infected individuals. Lesion severity on imaging is significantly associated with co-infection, highlighting imaging's diagnostic importance. Longer hospital stays are linked to co-infection but not significantly to death risk. Conclusions: Certain clinical and biological factors may serve as potential indicators of PTB co-infection in patients with SARS-CoV-2.

Primary Rifampicin Mono-Resistant Tuberculosis of the Cervical, Mediastinal, and Axillary Lymphadenopathy in an Indian Male: A First-of-Its-Type Case

Tuberculosis is common in endemic countries. However, extrapulmonary tuberculosis is relatively rare, and primary extrapulmonary rifampicin mono-resistant tuberculosis of the cervical, mediastinal, and axillary lymph nodes simultaneously without pulmonary focus in an immunocompetent male has never been reported. Herein is a case of a 27-year-old Indian male with no previous history of tuberculosis who was diagnosed after an extensive clinical assessment with a radiometric and cartridge-based nucleic acid amplification assay of the swollen lymph nodes. He was put on antituberculous treatment per the all-oral longer regimen of the national program.

Comparison of 3 diagnostic methods for pulmonary tuberculosis in suspected patients with negative sputum smear or no sputum

STUDY DESIGN

To explore the diagnostic value of 3 methods for sputum smear-negative and non-sputum patients with suspected pulmonary tuberculosis (TB).

METHODS

This prospective study enrolled sputum smear-negative and non-sputum patients with suspected TB admitted to Jiangxi Chest Hospital between January 2020 and December 2022. The 3 methods were bronchoalveolar lavage fluid (BALF)-acid-fast bacillus (AFB) smear, GeneXpert MTB/RIF, and gene chip for Mycobacterium strain identification. The diagnostic performance of the 3 tests was evaluated with BALF Mycobacterium culture + BALF-AFB smear + GeneXpert MTB/RIF + Gene chip as the gold standard.

RESULTS

A total of 456 samples were collected from 114 patients with suspected TB. Twenty-four patients were diagnosed with TB. The combination of GeneXpert MTB/RIF and gene chip for Mycobacterium strain identification yielded the highest area under the receiver operating characteristics curve (AUC) of 0.953 and had sensitivity of 90.57%, specificity of 100%, positive predictive value (PPV) of 100%, negative predictive value (NPV) of 92.42%, accuracy of 95.61%. GeneXpert MTB/RIF achieved AUC of 0.906, sensitivity of 81.13%, specificity of 100%, PPV of 100%, NPV of 85.92%, accuracy of 91.23%. BALF-AFB smear had AUC of 0.519, sensitivity of 3.77%, specificity of 100%, PPV of 100%, NPV of 54.46%, and accuracy of 55.26%. The combination of GeneXpert MTB/RIF and gene chip for Mycobacterium strain identification yielded the highest κ of 0.911, while BALF-AFB smear had the lowest κ value of 0.040.

CONCLUSION

For TB in sputum smear-negative and non-sputum patients using BALF Mycobacterium culture + BALF-AFB smear + GeneXpert MTB/RIF + Gene chip as the gold standard, BALF-AFB smear showed low diagnostic performance, while, though GeneXpert MTB/RIF and gene chip had good diagnostic performance, combining GeneXpert MTB/RIF and gene chip improved the diagnostic value to a great extent.

Tuberculosis Presenting as Chronic Monoarthritis: A Case Study

Mycobacterium tuberculosis infection remains a common disease in developing countries with the potential to involve the osteoarticular system. The authors report a case of knee arthritis due to tuberculosis (TB) in a 34-year-old woman. The patient presented with pain and swelling of the right knee as major complaints, without a history of respiratory symptoms. Magnetic resonance imaging (MRI) demonstrated a marked joint effusion, involving synovial tissue with cartilaginous lesion compatible with pigmented villonodular synovitis (PVNS). After several physiotherapy courses without significant relief, total knee arthroplasty was proposed. Two months after surgery and rehabilitation, symptoms did not completely resolve, with limited active range of motion. Microbial bone biopsy culture at the time of the arthroplasty revealed a TB infection. Due to the rarity and clinical nonspecificity of TB bone manifestations, early diagnosis may be challenging. Yet, attempted diagnosis and prompt pharmacological intervention are paramount to improve outcomes.

Cerebral Tuberculosis in a Patient Following Treatment With Infliximab for Ankylosing Spondylitis: A Case Report

Ankylosing spondylitis (AS) mainly belongs to the group of axial spondylitis. It is a chronic inflammatory disease that primarily affects the spine, but can also affect peripheral joints. It is characterized by inflammatory lower back pain and morning stiffness. Tuberculosis is still a cause of morbidity and mortality in developing countries. Management of patients with AS consists of patient education, spinal mobility exercises, non-steroidal anti-inflammatory drugs (NSAIDs), corticotherapy, and anti-tumor necrosis factor alpha (TNF-α) biological agents. Anti-TNF-α biological agents have changed the prognosis of patients with AS. They contain anti-TNF-α monoclonal antibodies (golimumab, infliximab, adalimumab, certolizumab) and the soluble TNF-α receptor (etanercept). Hip and knee involvement is common in patients with AS, as evidenced in radiographs as bone erosion and joint space narrowing. The patient may have severe pain, stiffness, and loss of mobility, and the treatment involves surgery for joint arthroplasty. We present the case of a 63-year-old patient with axial spondyloarthritis who was treated with infliximab and developed cerebral tuberculosis after three years of biological therapy. The purpose of the study is to determine the possibility of resuming biological therapy at the time of AS reactivation, given the long-term treatment and adverse reactions of cortisone therapy (aseptic necrosis of the femoral head).

An Insight into Advances in Developing Nanotechnology Based Therapeutics, Drug Delivery, Diagnostics and Vaccines: Multidimensional Applications in Tuberculosis Disease Management

Tuberculosis (TB), one of the deadliest contagious diseases, is a major concern worldwide. Long-term treatment, a high pill burden, limited compliance, and strict administration schedules are all variables that contribute to the development of MDR and XDR tuberculosis patients. The rise of multidrug-resistant strains and a scarcity of anti-TB medications pose a threat to TB control in the future. As a result, a strong and effective system is required to overcome technological limitations and improve the efficacy of therapeutic medications, which is still a huge problem for pharmacological technology. Nanotechnology offers an interesting opportunity for accurate identification of mycobacterial strains and improved medication treatment possibilities for tuberculosis. Nano medicine in tuberculosis is an emerging research field that provides the possibility of efficient medication delivery using nanoparticles and a decrease in drug dosages and adverse effects to boost patient compliance with therapy and recovery. Due to their fascinating characteristics, this strategy is useful in overcoming the abnormalities associated with traditional therapy and leads to some optimization of the therapeutic impact. It also decreases the dosing frequency and eliminates the problem of low compliance. To develop modern diagnosis techniques, upgraded treatment, and possible prevention of tuberculosis, the nanoparticle-based tests have demonstrated considerable advances. The literature search was conducted using Scopus, PubMed, Google Scholar, and Elsevier databases only. This article examines the possibility of employing nanotechnology for TB diagnosis, nanotechnology-based medicine delivery systems, and prevention for the successful elimination of TB illnesses.

Expert review for clinical and translational imaging actionable imaging findings in the daily PET/CT scenario

Background and aim

The American College of Radiology (ACR) defines "actionable findings" the ones requiring a special communication between radiologists and referring clinicians, suggesting to organize their categorization in a three-degree scale on the basis of the risk for the patient to develop complications. These cases may fall in a grey-zone communication between different care figures with the risk of being underestimated or even not being considered at all. In this paper, our aim is to adapt the ACR categorization to the most frequent actionable findings encountered when reporting PET/CT images in a Nuclear Medicine Department, describing the most frequent and relevant imaging features and presenting the modalities of communication and the related clinical interventions that can be modulated by the prognostic severity of the clinical cases.

Materials and methods

We performed a descriptive, observational and critical analysis of the most relevant literature on the topic of "actionable findings", in particular, starting from the reports of the ACR Actionable Reporting Work Group, we categorised and described, in a narrative review, the most relevant "actionable findings" encountered in the Nuclear Medicine PET/CT daily practice.

Results

To the best of our knowledge, to date there are no clear indications on this selective PET/CT topic, considering that the current recommendations target mainly radiologists and assume a certain level of radiological expertise. We resumed and classified the main imaging conditions under the term of "actionable findings" according to the corresponding anatomical districts, and we described their most relevant imaging features (independently of PET avidity or not). Furthermore, a different communication timing and strategy was suggested on the basis of the findings' urgency.

Conclusion

A systematic categorization of the actionable imaging findings according to their prognostic severity may help the reporting physician to choose how and when to communicate with the referring clinician or to identify cases requiring a prompt clinical evaluation. Effective communication is a critical component of diagnostic imaging: timely receipt of the information is more important than the method of delivery.

Role of Magnetic Resonance Imaging in evaluation of tuberculous tubo ovarian mass

OBJECTIVE

Role of Magnetic Resonance Imaging (MRI) in diagnosis of tuberculous tubo-ovarian (TO) mass.

METHODS

MRI was performed on 33 patients of tuberculous TO mass of female genital tuberculosis (FGTB).

RESULTS

Mean age, BMI, and parity was 27.5 ± 4.2 years, 22.7 ± 3.6 kg/m², and 0.27 ± 0.13. All patients (100%) had infertility; primary infertility (72.72%) and secondary infertility (27.23%) with mean 5.8 years. Abdominal/pelvic pain 33 (100%) cases, abdominal lump 4 (12.12%), adnexal mass 33 (100%). MRI findings showed pelvic masses 33 (100%), bilateral TO masses 11 (33.33%), cystic lesion 4 (12.12%), solid cystic lesion 3 (9.09%) with bilateral pyosalpinx 1 (3.3%), homogeneous content with ascites 1 (3.03%), rim enhancing lesion abutting pelvic wall in 1 (3.03%). Right adnexal mass 11 (33.33%), right adnexal cyst 2 (6.06%), right adnexal cystic mass in 1 (3.03%), right sided complex TO mass 1 (3.03%), right sided hydrosalpinx in 1 (3.03%) case, right sided TO mass in 4 (12.12%) cases and right sided para-ovarian cyst in 2 (6.06%). Left sided adnexal mass was seen in 11 (33.33%), cystic lesion in 1 (3.03%), ovarian cyst in 3 (9.09%) cases, left sided hydrosalpinx in 2 (6.06%), left ovarian cyst 2 (6.06%) cases, left sided ovarian cyst with encysted ascites 1 (3.03%) case and with left sided paraovarian cyst 2 (6.06%) case. Miscellaneous finding were generalised ascites (6.06%), encysted ascites (3.03%), pelvic (1; 3.03%) and mesenteric lymphadenopathy 1 (3.03%). Incidental finding were fibroid 3 (9.09%) and adenomyosis 1 (3.03%) case.

CONCLUSION

MRI appears to be useful diagnostic modality for tuberculous TO masses where differential diagnosis is malignancy but molecular diagnosis remains the gold standard.

Unusual patterns of tuberculosis on cross-sectional imaging: a pictorial review

Background

Tuberculosis is routinely encountered on imaging throughout the world. Radiologists are usually familiar with the common patterns of tuberculosis on cross-sectional imaging. However, tuberculosis frequently presents with unfamiliar imaging patterns and/or uncommon anatomic sites which still pose a diagnostic challenge.

Discussion

Rapid improvements in the management of acquired immunodeficiency syndrome patients leading to increased survival as well as advances in chemotherapy and immunosuppressive medication have complicated the presentation of tuberculosis by increasing the probability of unconventional sites and patterns of involvement in tuberculosis leading to unfamiliar imaging appearances. In this review, we describe these unfamiliar imaging patterns of tuberculosis and provide a diagnostic protocol for arriving at the right diagnosis and differentiating these from other pathologies with similar imaging appearances. These are described through case-based illustrations of unusual patterns and anatomic locations of tuberculosis.

Conclusions

It is important for radiologists to be aware of such unusual imaging patterns of tuberculosis in order to facilitate early and accurate diagnosis for appropriate patient management in the face of changing patient demographics and pathological profile of tuberculosis in the current era of scientific advancements.

Utility of PET/Computed Tomography in Infection and Inflammation Imaging

The role of nuclear medicine for noninvasive assessment of infection and inflammation is well established. The role of nuclear medicine is limited to initial diagnosis, recurrence, and response assessment of infections and inflammations such as tuberculosis, sarcoidosis, vasculitis, osteomyelitis, immunoglobulin G4-related diseases, and coronavirus disease 2019, as the specificity is affected by false positivity due to physiologic fluorodeoxyglucose uptake in specific organ and nonspecific uptake in postoperative cases. PET with fludeoxyglucose F 18/CT is a well-established modality for diagnosis of fever of unknown origin helping in optimized management of the patient.

PET/CT features of a novel gallium-68 labelled hypoxia seeking agent in patients diagnosed with tuberculosis: a proof-of-concept study

INTRODUCTION

Positron emission tomography/computed tomography (PET/CT) in infection and inflammation has yielded promising results across a range of radiopharmaceuticals. In particular, PET/CT imaging of tuberculosis (TB) allows for a better understanding of this complex disease by providing insights into molecular processes within the TB microenvironment. TB lesions are hypoxic with research primarily focussed on cellular processes occurring under hypoxic stress. With the development of hypoxia seeking PET/CT radiopharmaceuticals, that can be labelled in-house using a germanium-68/gallium-68 (68Ge/68Ga) generator, a proof-of-concept for imaging hypoxia in TB is presented.

METHODS

Ten patients diagnosed with TB underwent whole-body PET/CT imaging, 60-90 min after intravenous administration of 74-185 MBq (2-5 mCi) 68Ga-nitroimidazole. No oral or intravenous contrast was administered. Images were visually and semiquantitatively assessed for abnormal 68Ga-uptake in the lungs.

RESULTS

A total of 28 lesions demonstrating hypoxic uptake were identified. Low- to moderate-uptake was seen in nodules, areas of consolidation and cavitation as well as effusions. The mean standard uptake value (SUVmean) of the lesions was 0.47 (IQR, 0.32-0.82) and SUVmax was 0.71 (IQR, 0.41-1.11). The lesion to muscle ratio (median, 1.70; IQR, 1.15-2.31) was higher than both the left ventricular and the aorta lesion to blood ratios.

CONCLUSION

Moving towards the development of unique host-directed therapies (HDT), modulation of oxygen levels may improve therapeutic outcome by reprogramming TB lesions to overcome hypoxia. This proof-of-concept study suggests that hypoxia in TB lesions can be imaged and quantified using 68Ga-nitroimidazole PET/CT. Subsequently, hypoxic load can be estimated to inform personalised treatment plans of patients diagnosed with TB.

Tuberculosis conundrum - current and future scenarios: A proposed comprehensive approach combining laboratory, imaging, and computing advances

Tuberculosis (TB) remains a global threat, with the rise of multiple and extensively drug resistant TB posing additional challenges. The International health community has set various 5-yearly targets for TB elimination: mathematical modelling suggests that a 2050 target is feasible with a strategy combining better diagnostics, drugs, and vaccines to detect and treat both latent and active infection. The availability of rapid and highly sensitive diagnostic tools (Gene-Xpert, TB-Quick) will vastly facilitate population-level identification of TB (including rifampicin resistance and through it, multi-drug-resistant TB). Basic-research advances have illuminated molecular mechanisms in TB, including the protective role of Vitamin D. Also, Mycobacterium tuberculosis impairs the host immune response through epigenetic mechanisms (histone-binding modulation). Imaging will continue to be key, both for initial diagnosis and follow-up. We discuss advances in multiple imaging modalities to evaluate TB tissue changes, such as molecular imaging techniques (including pathogen-specific positron emission tomography imaging agents), non-invasive temporal monitoring, and computing enhancements to improve data acquisition and reduce scan times. Big data analysis and Artificial Intelligence (AI) algorithms, notably in the AI sub-field called “Deep Learning”, can potentially increase the speed and accuracy of diagnosis. Additionally, Federated learning makes multi-institutional/multi-city AI-based collaborations possible without sharing identifiable patient data. More powerful hardware designs - e.g., Edge and Quantum Computing- will facilitate the role of computing applications in TB. However, “Artificial Intelligence needs real Intelligence to guide it!” To have maximal impact, AI must use a holistic approach that incorporates time tested human wisdom gained over decades from the full gamut of TB, i.e., key imaging and clinical parameters, including prognostic indicators, plus bacterial and epidemiologic data. We propose a similar holistic approach at the level of national/international policy formulation and implementation, to enable effective culmination of TB’s endgame, summarizing it with the acronym “TB - REVISITED”.

The Diagnostic Deceiver: Radiological Pictorial Review of Tuberculosis

Tuberculosis (TB) is a bacterial infection with Mycobacterium tuberculosis; it is a public health problem worldwide and one of the leading causes of mortality. Since December 2019, the COVID-19 pandemic has created unprecedented health challenges and disrupted the TB health services, especially in high-burden countries with ever-increasing prevalence. Extrapulmonary and even pulmonary TB are an important cause of nonspecific clinical and radiological manifestations and can masquerade as any benign or malignant medical case, thus causing disastrous conditions and diagnostic dilemmas. Clinical manifestations and routine laboratory tests have limitations in directing physicians to diagnose TB. Medical-imaging examinations play an essential role in detecting tissue abnormalities and early suspecting diagnosis of TB in different organs. Radiologists and physicians should be familiar with and aware of the radiological manifestations of TB to contribute to the early suspicion and diagnosis of TB. The purpose of this article is to illustrate the common radiologic patterns of pulmonary and extrapulmonary TB. This article will be beneficial for radiologists, medical students, chest physicians, and infectious-disease doctors who are interested in the diagnosis of TB.

The diagnostic challenge of atypical tuberculous meningitis in children from rural area

Tuberculous meningitis (TBM) is a severe form of Mycobacterium tuberculosis infection, while its diagnosis is still a challenge in children. Here, six children with atypical TBM were retrospectively reviewed and the main findings were displayed as follows. The enrolled cases exhibited non-specific symptoms on admission, mainly including fever ( n = 5), headache ( n = 3), vomiting ( n = 5), and drowsiness ( n = 3), but no typical symptoms of TB infection. Two of them exhibited progressive symptoms under routine treatment. Cerebrospinal fluid (CSF) examinations revealed increased white blood cells and proteins, as well as decreased glucose and chloride in all cases. Chest imaging identified the possibly of pulmonary tuberculous in 2 cases. Cranial CT and MRI revealed neuroimaging abnormality in 1 and 3 cases, respectively. In addition, next-generation sequencing directly supported the diagnosis of TBM in case 5. To sum up, TBM should be highly suspected in children with central nervous system infection, when there are no improvements under routine treatment and/or the presence of progressive symptoms. Timely rechecking of CSF combined with cranial imaging is feasible and valuable for the diagnosis of TBM.

COVID-19 and pulmonary tuberculosis - A diagnostic dilemma

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Meanwhile, pulmonary tuberculosis(TB) is one of the most common infective lung diseases in developing nations. The concurrence of pulmonary TB and COVID-19 can lead to poor prognosis, owing to the pre-existing lung damage caused by TB. Case presentation: We describe the imaging findings in 3 cases of COVID-19 pneumonia with co-existing pulmonary TB on HRCT thorax. The concurrence of COVID-19 and pulmonary TB can be a diagnostic dilemma. Correct diagnosis and prompt management is imperative to reduce mortality and morbidity. Hence it is pertinent for imaging departments to identify and report these distinct entities when presenting in conjunction.

Contrast-enhanced endoscopic ultrasound features of tubercular lymphadenopathy

There is lack of data on the contrast-enhanced endoscopic ultrasound features of tubercular lymph node; our retrospective analysis of 37 patients with enlarged mediastinal and abdominal lymph nodes showed heterogeneous enhancement in the great majority (70%).

The silent pandemic in South Africa: Extra-pulmonary tuberculosis from head to heel

Extra-pulmonary tuberculosis (EPTB), caused by Mycobacterium tuberculosis, is the leading cause of communicable disease-related deaths in people with human immunodeficiency virus (HIV) worldwide and in South Africa. Mycobacterium tuberculosis disseminates haematogenously from an active primary lung focus and may affect extra-pulmonary sites in up to 15% of patients. Extra-pulmonary TB may present with a normal chest radiograph, which often causes a significant diagnostic dilemma. This review describes the main sites of involvement in EPTB, which is illustrated by local imaging examples.

Application of transthoracic shear-wave ultrasound elastography in lung lesions

INTRODUCTION

Tissue stiffness information may help in the diagnosis of lung lesions. This study aimed to investigate and validate the application of transthoracic two-dimensional shear-wave ultrasound elastography in differentiating malignant from benign subpleural lung lesions.

METHODS

This study involved one retrospective observational derivation cohort from January 2016 to December 2017 and one prospective observational validation cohort from December 2017 to December 2019. The inclusion criterion was radiographic evidence of pulmonary lesions. The patients were categorised into air bronchogram and hypoechoic groups based on B-mode grayscale images. The elasticity of subpleural lung lesions with acceptable shear-wave propagation was measured. Diagnoses were made on the basis of pathology, microbiological studies or following up the clinical course for at least 6 months.

RESULTS

A total of 354 patients were included. Among the 121 patients in the derivation cohort, a receiver operating characteristic curve was constructed and the cut-off point to differentiate benign from malignant lesions was 65 kPa with a Youden index of 0.60 and an accuracy of 84.3%. Among the 233 patients in the validation cohort, the diagnostic performance was maintained, with a Youden index of 0.65 and an accuracy of 86.7%. Upon applying the cut-off point to the air bronchogram group, the Youden index was 0.70 and the accuracy was 85.0%.

CONCLUSIONS

This study validated the application of transthoracic shear-wave ultrasound elastography for assessing lung malignancy. A cut-off point of 65 kPa is suggested for predicting lung malignancy. Furthermore, for pulmonary air bronchogram lesions with high elasticity, tissue proofing should be considered because of the high possibility of malignancy.

Trends in diagnostic methods and treatment of latent tuberculosis infection in a tertiary care center from 2000 to 2017

Screening for latent tuberculosis infection (LTBI) is indicated before immunosuppressive therapies but is complicated by lack of a gold standard and limited by, e.g., immunosuppression. This study aimed to investigate a series of patients diagnosed with LTBI during screening before immunosuppressive therapy, describing how the use of diagnostic tests and treatment evolved over time. This retrospective cohort study included all individuals diagnosed with LTBI during screening before intended immunosuppressive therapy in a tertiary care hospital between January 2000 and December 2017. Evidence for LTBI, including history, tuberculin skin test (TST), QuantiFERON (QFT) result and suggestive lesions on chest radiography (CXR), and CT scan if available, was analyzed. The study included 295 individuals with LTBI, with median follow-up of 3.8 years (IQR 1.7–7.4 years). During screening, TST, QFT, and CXR were positive in 80.8%, 53.4%, and 22.7%, respectively. Chest CT revealed lesions associated with past tuberculosis infection in around 70%, significantly more frequent than CXR. In patients diagnosed with LTBI, we observed that the use of TST declined over time whereas the use of QFT increased, and that isoniazid was replaced with rifampicin as preferential treatment. Preventive treatment was started in 82.3%, of whom 88.6% completed treatment. During follow-up, no individuals developed active tuberculosis. The diagnosis of LTBI was based on history, TST, QFT, and/or CXR in nearly every possible combination, but mostly on TST and QFT. The most striking trends were the decreased use of TST, increased use of QFT, and the replacement of isoniazid with rifampicin for treatment.

Quantitative 18F-FDG PET-CT scan characteristics correlate with tuberculosis treatment response

BACKGROUND

There is a growing interest in the use of F-18 FDG PET-CT to monitor tuberculosis (TB) treatment response. Tuberculosis lung lesions are often complex and diffuse, with dynamic changes during treatment and persisting metabolic activity after apparent clinical cure. This poses a challenge in quantifying scan-based markers of burden of disease and disease activity. We used semi-automated, whole lung quantification of lung lesions to analyse serial FDG PET-CT scans from the Catalysis TB Treatment Response Cohort to identify characteristics that best correlated with clinical and microbiological outcomes.

RESULTS

Quantified scan metrics were already associated with clinical outcomes at diagnosis and 1 month after treatment, with further improved accuracy to differentiate clinical outcomes after standard treatment duration (month 6). A high cavity volume showed the strongest association with a risk of treatment failure (AUC 0.81 to predict failure at diagnosis), while a suboptimal reduction of the total glycolytic activity in lung lesions during treatment had the strongest association with recurrent disease (AUC 0.8 to predict pooled unfavourable outcomes). During the first year after TB treatment lesion burden reduced; but for many patients, there were continued dynamic changes of individual lesions.

CONCLUSIONS

Quantification of FDG PET-CT images better characterised TB treatment outcomes than qualitative scan patterns and robustly measured the burden of disease. In future, validated metrics may be used to stratify patients and help evaluate the effectiveness of TB treatment modalities.

Spectrum of imaging findings in pulmonary infections. Part 2: Fungal, mycobacterial, and parasitic

Chest radiography is generally the first imaging modality used for the evaluation of pneumonia. It can establish the presence of pneumonia, determine its extent and location, and assess the response to treatment. Computed tomography is not used for the initial evaluation of pneumonia, but it may be used when the response to treatment is unusually slow. It helps to identify complications, detect any underlying chronic pulmonary disease, and characterise complex pneumonias. Although not diagnostic, certain imaging findings may suggest a particular microbial cause over others. Knowledge of whether pneumonia is community-acquired or nosocomial, as well as the age and immune status of the patient, can help to narrow the differential diagnoses. The purpose of this article is to briefly review the various pulmonary imaging manifestations of pathogenic organisms. This knowledge, along with the clinical history and laboratory investigations of the patient, may help to guide the treatment of pneumonia.

Can we predict tuberculosis cure? What tools are available?

Antibiotic treatment of tuberculosis takes ≥6 months, putting a major burden on patients and health systems in large parts of the world. Treatment beyond 2 months is needed to prevent tuberculosis relapse by clearing remaining, drug-tolerant Mycobacterium tuberculosis bacilli. However, the majority of patients treated for only 2-3 months will cure without relapse and do not need prolonged treatment. Assays that can identify these patients at an early stage of treatment may significantly help reduce the treatment burden, while a test to identify those patients who will fail treatment may help target host-directed therapies.In this review we summarise the state of the art with regard to discovery of biomarkers that predict relapse-free cure for pulmonary tuberculosis. Positron emission tomography/computed tomography scanning to measure pulmonary inflammation enhances our understanding of "cure". Several microbiological and immunological markers seem promising; however, they still need a formal validation. In parallel, new research strategies are needed to generate reliable tests.

The potential of imaging tools as correlates of infection and disease for new TB vaccine development

The development of an improved vaccine to stimulate an effective response against Mycobacterium tuberculosis (MTB) infection and disease will be a major breakthrough in the fight against TB. A lack of tools to adequately track the progression or resolution of events in TB pathogenesis that occur at bacterial loads below the threshold for culture in human samples seriously hampers vaccine development and evaluation. In this review we discuss recent studies that use new imaging applications, modalities and analysis techniques to provide insight into the dynamic processes of MTB infection and disease that are challenging to monitor. These include early infection, the spectrum of latency and subclinical disease, the paucibacillary state induced by treatment, and events leading to recurrence, including relapse.

Monitoring Response to Therapy

Monitoring response to treatment is a key element in the management of infectious diseases, yet controversies still persist on reliable biomarkers for noninvasive response evaluation. Considering the limitations of invasiveness of most diagnostic procedures and the issue of expression heterogeneity of pathology, molecular imaging is better able to assay in vivo biologic processes noninvasively and quantitatively. The usefulness of ¹⁸F-FDG-PET/CT in assessing treatment response in infectious diseases is more promising than for conventional imaging. However, there are currently no clinical criteria or recommended imaging modalities to objectively evaluate the effectiveness of antimicrobial treatment. Therapeutic effectiveness is currently gauged by the patient's subjective clinical response. In this review, we present the current studies for monitoring treatment response, with a focus on Mycobacterium tuberculosis, as it remains a major worldwide cause of morbidity and mortality. The role of molecular imaging in monitoring other infections including spondylodiscitis, infected prosthetic vascular grafts, invasive fungal infections, and a parasitic disease is highlighted. The role of functional imaging in monitoring lipodystrophy associated with highly active antiretroviral therapy for human immunodeficiency virus is considered. We also discuss the key challenges and emerging data in optimizing noninvasive response evaluation.

Tuberculous Meningitis in Children and Adults: New Insights for an Ancient Foe

PURPOSE OF REVIEW

Tuberculous meningitis is the most devastating manifestation of infection with Mycobacterium tuberculosis and represents a medical emergency. Approximately one half of tuberculous meningitis patients die or suffer severe neurologic disability. The goal of this review will be to review the pathogenic, clinical, and radiologic features of tuberculous meningitis and to highlight recent advancements in translational and clinical science.

RECENT FINDINGS

Pharmacologic therapy includes combination anti-tuberculosis drug regimens and adjunctive corticosteroids. It is becoming clear that a successful treatment outcome depends on an immune response that is neither too weak nor overly robust, and genetic determinants of this immune response may identify which patients will benefit from adjunctive corticosteroids. Recent clinical trials of intensified anti-tuberculosis treatment regimens conducted in Indonesia and Vietnam, motivated by the pharmacologic challenges of treating M. tuberculosis infections of the central nervous system, have yielded conflicting results regarding the survival benefit of intensified treatment regimens. More consistent findings have been observed regarding the relationship between initial anti-tuberculosis drug resistance and mortality among tuberculous meningitis patients. Prompt initiation of anti-tuberculosis treatment for all suspected cases remains a key aspect of management. Priorities for research include the improvement of diagnostic testing strategies and the optimization of host-directed and anti-tuberculosis therapies.

Imaging in extrapulmonary tuberculosis

Tuberculosis (TB) remains a major global public health problem, with 1.5 million deaths annually worldwide. One in five cases of TB present as extrapulmonary TB (EPTB), posing major diagnostic and management challenges. Mycobacterium tuberculosis adapts to a quiescent physiological state and is notable for its complex interaction with the host, producing poorly understood disease states ranging from latent infection to active clinical disease. New tools in the diagnostic armamentarium are urgently required for the rapid diagnosis of TB and monitoring of TB treatments, and to gain new insights into pathogenesis. The typical and atypical imaging features of EPTB are reviewed herein, and the roles of several imaging modalities for the diagnosis and management of EPTB are discussed.