Factors associated with false negative interferon-γ release assay results in patients with tuberculosis: A systematic review with meta-analysis

Plasma immune profiling combined with machine learning contributes to diagnosis and prognosis of active pulmonary tuberculosis

Tuberculosis (TB) remains one of the deadliest chronic infectious diseases globally. Early diagnosis not only prevents the spread of TB but also ensures effective treatment. However, the absence of non-sputum-based diagnostic tests often leads to delayed TB diagnoses. Inflammation is a hallmark of TB, we aimed to identify biomarkers associated with TB based on immune profiling. We collected 222 plasma samples from healthy controls (HCs), disease controls (non-TB pneumonia; PN), patients with TB (TB), and cured TB cases (RxTB). A high-throughput protein detection technology, multiplex proximity extension assays (PEA), was applied to measure the levels of 92 immune proteins. Based on differential analysis and the correlation with TB severity, we selected 9 biomarkers (CXCL9, PDL1, CDCP1, CCL28, CCL23, CCL19, MMP1, IFNγ and TRANCE) and explored their diagnostic capabilities through 7 machine learning methods. We identified combination of these 9 biomarkers that distinguish TB cases from controls with an area under the receiver operating characteristic curve (AUROC) of 0.89-0.99, with a sensitivity of 82-93% at a specificity of 88-92%. Moreover, the model excels in distinguishing severe TB cases, achieving AUROC exceeding 0.95, sensitivities and specificities exceeding 93.3%. In summary, utilizing targeted proteomics and machine learning, we identified a 9 plasma proteins signature that demonstrates significant potential for accurate TB diagnosis and clinical outcome prediction.

The role of chest X-rays when screening for latent tuberculosis infection in patients with inflammatory bowel disease before starting biologic treatment

BACKGROUND

Guidelines generally recommend a combination of immunological assays and chest X-ray imaging (CXR) when screening for latent tuberculosis infection (LTBI) prior to biologic treatment in inflammatory bowel disease (IBD).

OBJECTIVE

To investigate whether CXR identify patients with suspected LTBI/TB who were not identified with QuantiFERON tests (QFT) when screening for LTBI/TB before starting biologic treatment in IBD patients.

METHODS

Single-center, retrospective cohort study of patients with inflammatory bowel disease who had a QFT and a CXR prior to initiation of biologic treatment in a 5-year period (October 1st, 2017 to September 30th, 2022).

RESULTS

520 patients (56% female, mean age 40.1 years) were included. The majority had none or few risk factors for TB (as reflected by the demographic characteristics) but some risk factors for having false negative QFT results (concurrent glucocorticoid treatment and inflammatory activity). QFT results were positive in 8 patients (1.5%), inconclusive in 18 (3.5%) and negative in 494 (95.0%). Only 1 patient (0.19%) had CXR findings suspicious of LTBI. This patient also had a positive QFT and was subsequently diagnosed with active TB. All patients with negative or inconclusive QFT had CXR without any findings suggesting LTBI/TB. One patient developed active TB after having initiated biologic treatment in spite of having negative QFT and a normal CXR at screening.

CONCLUSION

In a population with low risk of TB, the benefits of supplementing the QFT with a CXR are limited and are unlikely to outweigh the cost in both patient test-burden, radioactive exposure, and economic resources.

Concomitant osimertinib and antituberculosis therapy in an elderly patient with EGFR-mutated lung cancer and pulmonary tuberculosis: A case report

The concurrent incidence of lung cancer and tuberculosis is expected to escalate due to the projected growth in the older population. Combination therapy with osimertinib and antituberculosis drugs has not been well-established. We report a case of successful treatment involving the concomitant administration of osimertinib and antituberculosis drugs in an older patient, an 89-year-old female, diagnosed with epidermal growth factor receptor (EGFR)-mutant lung cancer and pulmonary tuberculosis. Accumulating evidence is warranted to develop an optimal treatment strategy for patients with lung cancer and tuberculosis.

Toward a molecular microbial blood test for tuberculosis infection

The World Health Organization's aim to end the global tuberculosis (TB) epidemic by 2050 cannot be achieved without taking measures to identify people with asymptomatic Mycobacterium tuberculosis (Mtb) infection and offer them an intervention to reduce the risk of disease progression, such as preventive antimicrobial therapy. Implementation of this strategy is limited by the fact that existing tests for Mtb infection, which use immunosensitization to Mtb-specific antigens as a proxy for infection, have low positive predictive value for progression to TB. A blood test that detects Mtb deoxyribonucleic acid (DNA) could allow preventive therapy to be targeted at individuals with microbiological evidence of persistent infection. In this review, we summarize recent advances in the development of molecular microbial blood tests for Mtb infection and discuss potential explanations for discordance between their results and those of immunodiagnostic tests in adults with recent exposure to an infectious index case. We also present a roadmap for further development of molecular microbial blood tests for Mtb infection, and highlight the potential for research in this area to provide novel insights into the biology of Mtb infection and yield new tools to support efforts to control the global TB epidemic.

Antigen-specific chemokine profiles as biomarkers for detecting Mycobacterium tuberculosis infection

Background

Latent tuberculosis (TB) infection can progress to active TB, which perpetuates community transmission that undermines global TB control efforts. Clinically, interferon-γ release assays (IGRAs) are commonly used for active TB case detection. However, low IGRA sensitivity rates lead to false-negative results for a high proportion of active TB cases, thus highlighting IGRA ineffectiveness in differentiating MTB-infected individuals from healthy individuals.

Methods

Participants enrolled at Beijing Chest Hospital from May 2020-April 2022 were assigned to healthy control (HC), LTBI, IGRA-positive TB, and IGRA-negative TB groups. Screening cohort MTB antigen-specific blood plasma chemokine concentrations were measured using Luminex xMAP assays then were verified via testing of validation cohort samples.

Results

A total of 302 individuals meeting study inclusion criteria were assigned to screening and validation cohorts. Testing revealed significant differences in blood plasma levels of CXCL9, CXCL10, CXCL16, CXCL21, CCL1, CCL19, CCL27, TNF-α, and IL-4 between IGRA-negative TB and HC groups. Levels of CXCL9, CXCL10, IL-2, and CCL8 biomarkers were predictive for active TB, as reflected by AUC values of ≥0.9. CXCL9-based enzyme-linked immunosorbent assay sensitivity and specificity rates were 95.9% (95%CI: 91.7-98.3) and 100.0% (92.7-100.0), respectively. Statistically similar AUC values were obtained for CXCL9 and CXCL9-CXCL10 assays, thus demonstrating that combined analysis of CXCL10 and CXCL9 levels did not improve active TB diagnostic performance.

Conclusion

The MTB antigen stimulation-based CXCL9 assay may compensate for low IGRA diagnostic accuracy when used to diagnose IGRA-negative active TB cases and thus is an accurate and sensitive alternative to IGRAs for detecting MTB infection.

The changes and its significance of peripheral blood NK cells in patients with tuberculous meningitis

Objective

Tuberculous meningitis (TBM) is the most severe form of tuberculosis (TB). The purpose of this study was to explore the relationship between the number of natural killer (NK) cells and adaptive immune status, and disease severity in TBM patients.

Methods

We conducted a retrospective study on 244 TB patients and 146 healthy control subjects in the 8th Medical Center of the PLA General Hospital from March 2018 and August 2023.

Results

The absolute count of NK cells in the peripheral blood of TBM patients was significantly lower than that in normal controls (NC), latent tuberculosis infection (LTBI), and non-severe TB (NSTB) patients (p < 0.05). The proportion of TBM patients (48.7%) with a lower absolute count of NK cells than the normal reference value was significantly higher than that in NC (5.2%) and LTBI groups (4.0%) (p < 0.05), and slightly higher than that in NSTB group (36.0%) (p > 0.05). The absolute counts of lymphocyte subsets in TBM combined with other active TB group, etiology (+) group, IGRA (-) group, and antibody (+) group were lower than that in simple TBM group, etiology (-) group, IGRA (+) group, and antibody (-) group, respectively. The CD3+ T, NK, and B cells in BMRC-stage III TBM patients were significantly lower than those in stage I and stage II patients (p < 0.05). The counts of CD3+ T, CD4+ T, and B cells in the etiology (+) group were significantly lower than those in the etiology (-) group (p < 0.05).

Conclusion

The absolute counts of lymphocyte subsets in the peripheral blood of TBM patients were significantly decreased, especially in NK cells. The reduction of these immune cells was closely related to the disease severity and had a certain correlation with cellular and humoral immune responses. This study helps to better understand the immune mechanism of TBM and provides reliable indicators for evaluating the immune status of TBM patients in clinical practice.

Disseminated tuberculosis after anti-TNF alpha treatment: Do not blindly trust the IGRA test

INTRODUCTION

Interferon gamma release assay (IGRA) is used to detect latent tuberculosis prior to biological treatments in the context of suspected inflammatory rheumatism.

METHODS

We report the case of a 50-year-old woman with negative IGRA test before adalimumab introduction for presumed axial spondyloarthritis.

RESULTS

The worsening of symptoms under treatment led to further investigations and the diagnostic of disseminated tuberculosis (TB) was later established with miliary and multiple bone locations such as spondylitis and sacroilitis. The patient's history revealed past exposure to tuberculosis. This observation illustrates the limitations of IGRA in such situation due to its variable performance for active TB diagnosis.

CONCLUSION

Misdiagnosis is frequent in bone tuberculosis due to non-specific signs. We draw the attention to the importance of a global risk assessment prior to the introduction of biological treatment for suspected chronic inflammatory rheumatism and recall the risk factors for false-negative IGRA. An extended treatment course may be necessary after exposure to anti-TNF-alpha.

Integrating SARS-CoV-2-specific interferon-γ release assay testing in the evaluation of patients hospitalized with COVID-19

IMPORTANCE

The cellular immune response is essential in the protection against severe disease in patients with established SARS-CoV-2 infection. The novelty of this study lies in the evaluation of the overall performance of a standardized assay to measure cellular immune response, the SARS-CoV-2-specific interferon-γ release assay (IGRA), in hospitalized patients with severe COVID-19. The SARS-CoV-2 IGRA was shown to accurately classify patients based on disease severity and prognosis, and the study revealed that test performance was not affected by the SARS-CoV-2 variant or control tube results. We identified an assay cut-off point with a high negative predictive value against mortality. The SARS-CoV-2 IGRA in patients hospitalized for COVID-19 may be a useful tool to assess cellular immunity and adopt targeted therapeutic and preventive measures.

Resuming anti-TNF therapy after development of miliary tuberculosis in Behcet's disease-related uveitis: a case report

PURPOSE

There is no consensus concerning restarting anti-tumour necrosis factor (TNF)-α therapy for uveitis after treatment for active tuberculosis (TB). We report a case of Behcet disease (BD) in which treatment with TNF inhibitor was successfully resumed after treatment for miliary TB.

CASE REPORT

A 48-year-old Japanese male was treated for uveitis of unknown aetiology in the left eye at a general ophthalmology clinic. He was referred to Department of Ophthalmology, Tokyo Medical University Hospital because of macula oedema (ME) not responding to prednisolone (PSL) 20 mg. BD was diagnosed based on fluorescein angiographic findings of diffuse retinal vasculitis characteristic of BD, recurrent oral aphthous ulcer, erythema nodosum-like rash in his legs, and HLA-A26 positivity. After a screening test, adalimumab (ADA) was started as steroid-sparing therapy. Eight months after starting ADA, the patient was diagnosed with miliary TB. ADA and PSL were discontinued immediately due to TB. Anti-TB treatment was completed after 6 months based on clinical improvement, although T-SPOT.TB was still positive. Infliximab with isoniazid was started due to relapse of ME, worsened vitreous haze, and worsened visual acuity in his left eye. Subsequently, his ocular symptoms subsided and there was no relapse of TB.

CONCLUSION

This case suggests that in patients with BD who have discontinued anti-TNF therapy due to miliary TB, restarting anti-TNF therapy may be a therapeutic option after TB has been treated appropriately with careful monitoring for relapse.

Latent tuberculosis infection in myasthenia gravis patients on immunosuppressive therapy: high incidence yet moderate reactivation rate

BACKGROUND

Immunosuppressive therapies (ISTs) are mainstays for management of myasthenia gravis (MG). Meanwhile, latent tuberculosis infection (LTBI) is common in the setting of high-burden countries. However, the prevalence of LTBI among MG patients and whether receiving ISTs for MG would aggravate LTBI reactivation remain unknown.

METHODS

We retrospectively analyzed the frequency of LTBI via interferon-gamma release assay (IGRA) positivity among hospitalized MG patients from both rural and urban areas in a tertiary hospital, and those receiving ISTs were followed up to investigate the reactivation risk of LTBI.

RESULTS

A total of 300 MG patients with determinate IGRA results were enrolled, where the frequency of LTBI was 35.0%. Male (OR = 1.910, 95% CI: 1.181-3.089, p = .008) and elderly (OR = 1.044, 95% CI: 1.027-1.061, p < .001) patients were prone to LTBI. Of those with LTBI, 78 individuals on ISTs were successfully followed up for a median duration of 18.3 (8.5-24.0) months, of which 25 (32.1%) received anti-tuberculosis (TB) treatments. The rate of various degrees of adverse events was 82.1% over the course of the follow-up, but was not different between individuals with and without therapies against TB (χ2 < 0.001, p > .999). Only 1 patient eventually reported lymph node and intestinal TB, with the incidence rate of LTBI reactivation preliminarily estimated to be 0.81 per 100 person years.

CONCLUSION

The frequency of LTBI is high in our MG cohort, especially among those with advanced age and males. However, receiving immunosuppressives seems not to increase the risk of LTBI reactivation. LTBI screening is strongly recommended for all MG patients ready to receive ISTs, while preventive anti-TB chemotherapy should be prescribed after weighing potential benefits against the risk of side effects in those with LTBI. In-depth investigation is still entailed to further verify these findings due to the limitation of the retrospective single-center design of our study.

Understanding the Decline of Incident, Active Tuberculosis in People With Human Immunodeficiency Virus in Switzerland

BACKGROUND

People with human immunodeficiency virus type 1 (HIV-1) (PWH) are frequently coinfected with Mycobacterium tuberculosis (MTB) and at risk for progressing from asymptomatic latent TB infection (LTBI) to active tuberculosis (TB). LTBI testing and preventive treatment (TB specific prevention) are recommended, but its efficacy in low transmission settings is unclear.

METHODS

We included PWH enrolled from 1988 to 2022 in the Swiss HIV Cohort study (SHCS). The outcome, incident TB, was defined as TB ≥6 months after SHCS inclusion. We assessed its risk factors using a time-updated hazard regression, modeled the potential impact of modifiable factors on TB incidence, performed mediation analysis to assess underlying causes of time trends, and evaluated preventive measures.

RESULTS

In 21 528 PWH, LTBI prevalence declined from 15.1% in 2001% to 4.6% in 2021. Incident TB declined from 90.8 cases/1000 person-years in 1989 to 0.1 in 2021. A positive LTBI test showed a higher risk for incident TB (hazard ratio [HR] 9.8, 5.8-16.5) but only 10.5% of PWH with incident TB were tested positive. Preventive treatment reduced the risk in LTBI test positive PWH for active TB (relative risk reduction, 28.1%, absolute risk reduction 0.9%). On population level, the increase of CD4 T-cells and reduction of HIV viral load were the main driver of TB decrease.

CONCLUSIONS

TB specific prevention is effective in selected patient groups. On a population level, control of HIV-1 remains the most important factor for incident TB reduction. Accurate identification of PWH at highest risk for TB is an unmet clinical need.

Uniting for Ukraine Tuberculosis Screening Experience, San Francisco, California, USA

Ukraine surveillance data suggest high tuberculosis (TB) incidence, including multidrug resistance. Of 299 newcomers from Ukraine screened in San Francisco, California, USA, by using an interferon-γ-release-assay (IGRA) and chest radiograph, 7.4% were IGRA positive and 1 had laboratory-confirmed pansusceptible TB. Screening with IGRA and chest radiograph can help characterize TB risk.

Smoking is a Factor in Discordance Between QuantiFERONTB Gold Assay and Tuberculosis Etiology: Especially in Older Patients

Purpose

Exploring whether smoking is an influencing factor for the inconsistency between QuantiFERONTB Gold assay (QFT-GIT) and tuberculosis etiology.

Patients and Methods

The clinical data of patients who were confirmed positive for Mycobacterium tuberculosis (MTB) after undergoing QFT-GIT testing from September 2017 to August 2021 were retrospectively analyzed. Chi-square and rank-sum tests were used to compare the differences in characteristics between smokers and non-smokers. Logistic regression was used to adjust for confounding factors affecting smoking. Propensity score matching (PSM) was used to verify the above conclusions again.

Results

Positive results of tuberculosis etiology were adopted as the standard, the incidence of inconsistent results between QFT-GIT and tuberculosis etiology was 8.90% (108/1213), of which the false negative rate was 6.27% (76/1213) and the indeterminate rate was 2.64% (32/1213). In the overall population, the smokers had a lower level of basal IFN-γ (Z=-2.079, P=0.038). Among 382 elderly (≥65 years old) patients, the smokers had lower levels of antigen-stimulated IFN-γ (Z=-2.838, P=0.005). After performing BOX-COX transformation on all non-normally distributed data, logistic stepwise regression was used to adjust confounding factors. The results showed that smoking was an influencing factor for the inconsistency between QFT-GIT and tuberculosis etiology results (OR=1.69, P=0.020). Using PSM for 1:2 matching, the results showed that smoking was still an independent risk factor for the inconsistent results of QFT-GIT and tuberculosis etiology (OR= 1.95, P=0.019). Age-stratified analysis showed that smoking was an independent risk factor in discordance between QFT-GIT and tuberculosis etiology in patients aged ≥65 years (OR=2.40, P=0.005), but not in patients aged <65 years (P > 0.05).

Conclusion

Smoking can reduce the body's IFN-γ release ability, and smoking (especially the elderly) is an influencing factor for the inconsistency between QFT-GIT and tuberculosis etiological results.

An unusual case of pleural effusion

CASE PRESENTATION

A 63-year-old man presented with fever, thoracalgia, weight loss, diffuse lymphadenopathy, and a massive pleural effusion. Extensive laboratory and radiologic investigations for possible autoimmune, infectious, hematologic, and neoplastic conditions all resulted negative. A lymph node biopsy showed a granulomatous necrotizing lymphadenitis, suspicious for tuberculosis. Although mycobacterium tuberculosis (MT) was never isolated and tuberculin skin test resulted negative, diagnosis of extrapulmonary tuberculosis was made and anti-tubercular therapy was started. Despite the strict adherence to 5 months of treatment, he returned to the emergency ward complaining of fever, chest pain and pleural effusion; total-body CT and PET scans demonstrated a progression of new disseminated nodular consolidations.

DIAGNOSTIC WORK-UP

Microscopic and cultural search for MT and other micro-organisms resulted again negative on urine, stool, blood, pleural fluid, and spinal lesion biopsy. We therefore started considering alternative diagnosis for necrotizing granulomatosis, including multidrug-resistant tuberculosis, Wegener granulomatosis, Churg Strauss syndrome, necrobiotic nodules of rheumatoid arthritis, lymphomatoid granulomatosis and Necrotizing Sarcoid Granulomatosis (NSG). Having already rejected other autoimmune, hematological, and neoplastic disorders, NSG resulted the most consistent hypothesis. With an expert we thus re-examined histological specimens that were suggestive for an atypical presentation of sarcoidosis. Steroid therapy was initiated, achieving symptoms improvement.

DISCUSSION

Sarcoidosis is a rare condition that can be challenging to diagnose, due to its variability in clinical presentation, often mimicking alternative conditions like disseminated tuberculosis. A high degree of suspicion and an experienced lab in anatomical pathology are essential for final diagnosis.

Differential diagnosis of pulmonary sarcoidosis: a review

Diagnosing pulmonary sarcoidosis raises challenges due to both the absence of a specific diagnostic criterion and the varied presentations capable of mimicking many other conditions. The aim of this review is to help non-sarcoidosis experts establish optimal differential-diagnosis strategies tailored to each situation. Alternative granulomatous diseases that must be ruled out include infections (notably tuberculosis, nontuberculous mycobacterial infections, and histoplasmosis), chronic beryllium disease, hypersensitivity pneumonitis, granulomatous talcosis, drug-induced granulomatosis (notably due to TNF-a antagonists, immune checkpoint inhibitors, targeted therapies, and interferons), immune deficiencies, genetic disorders (Blau syndrome), Crohn's disease, granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and malignancy-associated granulomatosis. Ruling out lymphoproliferative disorders may also be very challenging before obtaining typical biopsy specimen. The first step is an assessment of epidemiological factors, notably the incidence of sarcoidosis and of alternative diagnoses; exposure to risk factors (e.g., infectious, occupational, and environmental agents); and exposure to drugs taken for therapeutic or recreational purposes. The clinical history, physical examination and, above all, chest computed tomography indicate which differential diagnoses are most likely, thereby guiding the choice of subsequent investigations (e.g., microbiological investigations, lymphocyte proliferation tests with metals, autoantibody assays, and genetic tests). The goal is to rule out all diagnoses other than sarcoidosis that are consistent with the clinical situation. Chest computed tomography findings, from common to rare and from typical to atypical, are described for sarcoidosis and the alternatives. The pathology of granulomas and associated lesions is discussed and diagnostically helpful stains specified. In some patients, the definite diagnosis may require the continuous gathering of information during follow-up. Diseases that often closely mimic sarcoidosis include chronic beryllium disease and drug-induced granulomatosis. Tuberculosis rarely resembles sarcoidosis but is a leading differential diagnosis in regions of high tuberculosis endemicity.

Challenges and the Way forward in Diagnosis and Treatment of Tuberculosis Infection

Globally, it is estimated that one-quarter of the world's population is latently infected with Mycobacterium tuberculosis (Mtb), also known as latent tuberculosis infection (LTBI). Recently, this condition has been referred to as tuberculosis infection (TBI), considering the dynamic spectrum of the infection, as 5-10% of the latently infected population will develop active TB (ATB). The chances of TBI development increase due to close contact with index TB patients. The emergence of multidrug-resistant TB (MDR-TB) and the risk of development of latent MDR-TB has further complicated the situation. Detection of TBI is challenging as the infected individual does not present symptoms. Currently, there is no gold standard for TBI diagnosis, and the only screening tests are tuberculin skin test (TST) and interferon gamma release assays (IGRAs). However, these tests have several limitations, including the inability to differentiate between ATB and TBI, false-positive results in BCG-vaccinated individuals (only for TST), false-negative results in children, elderly, and immunocompromised patients, and the inability to predict the progression to ATB, among others. Thus, new host markers and Mtb-specific antigens are being tested to develop new diagnostic methods. Besides screening, TBI therapy is a key intervention for TB control. However, the long-course treatment and associated side effects result in non-adherence to the treatment. Additionally, the latent MDR strains are not susceptible to the current TBI treatments, which add an additional challenge. This review discusses the current situation of TBI, as well as the challenges and efforts involved in its control.

Contextualizing and optimizing novel strategies to improve the latent TB continuum of care: Insights from people living with HIV and health care providers in Brazil

Tuberculosis (TB) causes 1 in 3 deaths among people living with HIV (PLHIV). Diagnosing and treating latent tuberculosis infection (LTBI) is critical to reducing TB incidence and mortality. Blood-based screening tests (e.g., QuantiFERON-TB Gold Plus (QFT+)) and shorter-course TB preventive therapy (TPT) regimens such as 3HP (3 months weekly isoniazid-rifapentine) hold significant promise to improve TB outcomes. We qualitatively explored barriers and solutions to optimizing QFT+ and 3HP among PLHIV in three cities in Brazil. We conducted 110 in-depth interviews with PLHIV, health care providers (HCP) and key informants (KI). Content analysis was conducted including the use of case summaries and comparison of themes across populations and contexts. LTBI screening and treatment practices were dependent on HCP's perceptions of whether they were critical to improving TB outcomes. Many HCP lacked a strong understanding of LTBI and perceived the current TPT regimen as complicated. HCP reported that LTBI screening and treatment were constrained by clinic staffing challenges. While PLHIV generally expressed willingness to consider any test or treatment that doctors recommended, they indicated HCP rarely discussed LTBI and TPT. TB testing and treatment requests were constrained by structural factors including financial and food insecurity, difficulties leaving work for appointments, stigma and family responsibilities. QFT+ and 3HP were viewed by all participants as tools that could significantly improve the LTBI cascade by avoiding complexities of TB skin tests and longer LTBI treatment courses. QFT+ and 3HP were perceived to have challenges, including the potential to increase workload on over-burdened health systems if not implemented alongside improved supply chains, staffing, and training, and follow-up initiatives. Multi-level interventions that increase understanding of the importance of LTBI and TPT among HCP, improve patient-provider communication, and streamline clinic-level operations related to QFT+ and 3HP are needed to optimize their impact among PLHIV and reduce TB mortality.

Clinical characteristics and diagnosis of intestinal tuberculosis in clinical practice at Thailand's largest national tertiary referral center: An 11-year retrospective review

BACKGROUND

Diagnosing intestinal tuberculosis (ITB) is challenging due to the low diagnostic sensitivity of current methods. This study aimed to assess the clinical characteristics and diagnosis of ITB at our tertiary referral center, and to explore improved methods of ITB diagnosis.

METHODS

This retrospective study included 177 patients diagnosed with ITB at Siriraj Hospital (Bangkok, Thailand) during 2009-2020.

RESULTS

The mean age was 49 years, 55.4% were male, and 42.9% were immunocompromised. Most diagnoses (108/177) were made via colonoscopy; 12 patients required more than one colonoscopy. Among those, the sensitivity of tissue acid-fast bacilli (AFB), presence of caseous necrosis, polymerase chain reaction (PCR), and culture was 40.7%, 13.9%, 25.7%, and 53.4%, respectively. Among patients with negative tissue histopathology, 4 (3.7%) and 13 (12.0%) were ITB positive on tissue PCR and culture, respectively. The overall sensitivity when all diagnostic methods were used was 63%. Seventy-six patients had stool tests for mycobacteria. The overall sensitivity of stool tests was 75.0%. However, when analyzing the 31 patients who underwent both endoscopy and stool testing, the sensitivity of stool testing when using tissue biopsy as a reference was 45.8%. Combining stool testing and tissue biopsy did not significantly increase the sensitivity compared to tissue biopsy alone (83.9% vs. 77.4%, respectively).

CONCLUSION

Despite the availability of PCR and culture for TB, the overall diagnostic sensitivity was found to be low. The sensitivity increased when the tests were used in combination. Repeated colonoscopy may be beneficial. Adding stool mycobacteria tests did not significantly increase the diagnostic yield if endoscopy was performed, but it could be beneficial if endoscopy is unfeasible.

Determinants of QuantiFERON Plus-diagnosed tuberculosis infection in adult Ugandan TB contacts: A cross-sectional study

BACKGROUND

The tuberculin skin test is commonly used to diagnose latent tuberculosis infection (LTBI) in resource-limited settings, but its specificity is limited by factors including cross-reactivity with BCG vaccine and environmental mycobacteria. Interferon-gamma release assays (IGRA) overcome this problem by detecting M. tuberculosis complex-specific responses, but studies to determine risk factors for IGRA-positivity in high TB burden settings are lacking.

METHODS

We conducted a cross-sectional study to determine factors associated with a positive IGRA by employing the QuantiFERON-TB® Gold-plus (QFT Plus) assay in a cohort of asymptomatic adult TB contacts in Kampala, Uganda. Multivariate logistic regression analysis with forward stepwise logit function was employed to identify independent correlates of QFT Plus-positivity.

RESULTS

Of the 202 participants enrolled, 129/202 (64%) were female, 173/202 (86%) had a BCG scar, and 67/202 (33%) were HIV-infected. Overall, 105/192 (54%, 95% CI 0.48-0.62) participants had a positive QFT Plus result. Increased risk of QFT-Plus positivity was independently associated with casual employment/unemployment vs. non-casual employment (adjusted odds ratio (aOR) 2.18, 95% CI 1.01-4.72), a family vs. non-family relation to the index patient (aOR 2.87, 95% CI 1.33-6.18), living in the same vs. a different house as the index (aOR 3.05, 95% CI 1.28-7.29), a higher body mass index (BMI) (aOR per additional kg/m2 1.09, 95% CI 1.00-1.18) and tobacco smoking vs. not (aOR 2.94, 95% CI 1.00-8.60). HIV infection was not associated with QFT-Plus positivity (aOR 0.91, 95% CI 0.42-1.96).

CONCLUSION

Interferon Gamma Release Assay positivity in this study population was lower than previously estimated. Tobacco smoking and BMI were determinants of IGRA positivity that were previously unappreciated.

Interferon-gamma release assays in tuberculous uveitis: a comprehensive review

Tuberculous uveitis (TBU) comprises a broad clinical spectrum of ocular manifestations, making its diagnosis challenging. Ophthalmologists usually require evidence from investigations to confirm or support a clinical diagnosis of TBU. Since direct isolation of the causative organism from ocular specimens has limitations owing to the small volume of the ocular specimens, resultant test positivities are low in yield. Immunodiagnostic tests, including the tuberculin skin test and interferon-gamma release assays (IGRAs), can help support a clinical diagnosis of TBU. Unlike the tuberculin skin test, IGRAs are in vitro tests that require a single visit and are not affected by prior Bacillus Calmette-Guerin vaccination. Currently, available IGRAs consist of different techniques and interpretation methods. Moreover, newer generations have been developed to improve the sensitivity and ability to detect active tuberculosis. This narrative review collates salient practice points as a reference for general ophthalmologists, such as evidence for the utilization of IGRAs in patients with suspected TBU, and summarizes basic knowledge and details of clinical applications of these tests in a clinical setting.

Significant difference in Th1/Th2 paradigm induced by tuberculosis-specific antigens between IGRA-positive and IGRA-negative patients

False negative interferon-γ release assay (IGRA) results constitute the major dilemma for the diagnosis of tuberculosis (TB) infections. Herein, we conducted a cohort study to compare the host immunological response to TB-specific antigens between active TB patients with positive and negative IGRA results and control groups. A total of 274 laboratory-confirmed TB patients were included in our analysis, consisting of 221 were IGRA positive and 53 were IGRA negative. Patients with the elderly were identified as an independent risk factor for negative IGRA results. In addition, the elevated level of IL-4 and the decreased levels of IFN-γ, IL-2, IL-6, IL-1β, and IL-12 in IGRA negative TB relative to IGRA positive TB group, demonstrating a significant difference in Th1/Th2 paradigm between two groups. The IFN-γ&IL-2 based assay could correctly identify 247 out of 307 MTB-infected individuals [271 TB patients and 36 individuals with latent TB infection (LTBI)], demonstrating a sensitivity of 80.5%. Then the IFN-γ and IL-4 were applied to distinguish healthy control and IGRA-negative group. When using the stepwise algorithm, the sensitivity for detecting Mycobacterium tuberculosis (MTB) infections was significantly increased from 80.5% to 89.6%. Additionally, patients with negative IGRA results had a conversion to culture-negative status longer than those with positive IGRA results. In conclusion, a stepwise algorithm outperforms IGRA assays to accurately identify MTB infections by the combination IFN-γ, IL-2, and IL-4. Further study is needed to evaluate the accuracy of our diagnostic algorithm in the LTBI population.

A narrative review of tuberculosis in the United States among persons aged 65 years and older

Tuberculosis (TB) is a preventable infectious disease that confers significant morbidity, mortality, and psychosocial challenges. As TB incidence in the United States (U.S.) decreased from 9.7/100,000 to 2.2/100,000 from 1993 to 2020, the proportion of cases occurring among adults aged 65 and older increased. We conducted a review of published literature in the U.S. and other similar low-TB-burden settings to characterize the epidemiology and unique diagnostic challenges of TB in older adults. This narrative review also provides an overview of treatment characteristics, outcomes, and research gaps in this patient population. Older adults had a 30% higher likelihood of delayed TB diagnosis, with contributing factors such as acid-fast bacilli sputum smear-negative disease (56%) and non-classical clinical presentation. At least 90% of TB cases among older adults resulted from reactivation of latent TB infection (LTBI), but guidance around when to screen and treat LTBI in these patients is lacking. In addition, routine TB testing methods such as interferon-gamma release assays were two times more likely to have false-negative results among older adults. Advanced age was also often accompanied by complex comorbidities and impaired drug metabolism, increasing the risk of treatment failure (23%) and death (19%). A greater understanding of the unique factors of TB among older adults will inform clinical and public health efforts to improve outcomes in this complex patient population and TB control in the U.S.

Correlation between tuberculosis-specific interferon-γ release assay and intrathoracic calcification: A cross-sectional study

Background

Although persistent tuberculosis (TB) infection is known to cause calcification in the lungs, the relationship between intrathoracic calcification and the results of the interferon-γ release assay (IGRA) has not been fully elucidated. This study aimed to assess the association between intrathoracic calcification and IGRA results.

Methods

We retrospectively included consecutive patients who concurrently underwent chest X-ray, chest computed tomography (CT), and an IGRA. Patients with a current diagnosis of active TB or treatment history of active TB or latent tuberculosis infection (LTBI) were excluded. The association between calcification according to the chest X-ray or CT and IGRA results were analyzed using binomial logistic regression.

Results

This study included 574 patients, and 38 (7%) patients had a positive IGRA result. Patients with a positive result were significantly older and had a higher proportion of comorbidities, and history of tuberculosis exposure compared to those with a negative result. Calcification of the lung field and mediastinal lymph nodes according to chest CT was more frequently observed in patients with a positive IGRA result, whereas no significant difference was observed concerning the proportion of lung field calcification on chest X-ray between patients with positive and negative IGRA results. In multivariate analysis, calcification of mediastinal lymph nodes alone (adjusted odds ratio [OR] = 3.82, 95% confidence interval [CI] = 1.76–8.26) and the combination of lung field and mediastinal lymph node calcification (adjusted OR = 4.12, 95% CI = 1.51–11.76) on chest CT was independently associated with positive IGRA results.

Conclusions

The finding of mediastinal lymph node calcification, with or without lung field calcification, on chest CT was associated with positive IGRA results independent of TB exposure history. Previous TB infection including eliminated TB infection and LTBI can be suspected when calcified lymph nodes in are observed the mediastinum on chest CT.

Pathogenesis of SARS-CoV-2 and Mycobacterium tuberculosis Coinfection

Coronavirus disease-2019 (COVID-19), caused by SARS-CoV-2, is an infectious disease that poses severe threats to global public health and significant economic losses. The COVID-19 global burden is rapidly increasing, with over 246.53 million COVID-19 cases and 49.97 million deaths reported in the WHO 2021 report. People with compromised immunity, such as tuberculosis (TB) patients, are highly exposed to severe COVID-19. Both COVID-19 and TB diseases spread primarily through respiratory droplets from an infected person to a healthy person, which may cause pneumonia and cytokine storms, leading to severe respiratory disorders. The COVID-19-TB coinfection could be fatal, exacerbating the current COVID-19 pandemic apart from cellular immune deficiency, coagulation activation, myocardial infarction, and other organ dysfunction. This study aimed to assess the pathogenesis of SARS-CoV-2-Mycobacterium tuberculosis coinfections. We provide a brief overview of COVID19-TB coinfection and discuss SARS-CoV-2 host cellular receptors and pathogenesis. In addition, we discuss M. tuberculosis host cellular receptors and pathogenesis. Moreover, we highlight the impact of SARS-CoV-2 on TB patients and the pathological pathways that connect SARS-CoV-2 and M. tuberculosis infection. Further, we discuss the impact of BCG vaccination on SARS-CoV-2 cases coinfected with M. tuberculosis, as well as the diagnostic challenges associated with the coinfection.

Diagnostic accuracy of interferon-gamma release assays for diagnosis of smear-negative pulmonary tuberculosis: a systematic review and meta-analysis

Introduction

The diagnosis of smear-negative pulmonary tuberculosis (SNPTB) is challenging. Interferon gamma-release assays (IGRAs) may be helpful in early diagnosis among these patients resulting in prompt treatment and favorable outcomes.

Methods

We performed a comprehensive search from each databases’ inception to April 5, 2021. The studies that provided sufficient data regarding the sensitivity and specificity of IGRAs included QuantiFERON-TB Gold In-Tube (QFT-GIT), T-SPOT.TB, or QuantiFERON-TB Gold Plus for diagnosis of SNPTB were included.

Results

Of 1,312 studies screened, 16 studies were included; 11 QFT-GIT, 2 T-SPOT.TB, and 3 QFT-GIT and T-SPOT.TB. For diagnosis of SNPTB, QFT-GIT had sensitivity of 0.77 (95% CI 0.71–0.82), specificity of 0.70 (95% CI 0.58–0.80), diagnostic odds ratio (DOR) of 8.03 (95% CI 4.51–14.31), positive likelihood ratio (LR) of 2.61 (95% CI 1.80–3.80), negative LR of 0.33 (95% CI 0.25–0.42), and area under receiver operating characteristic (AUROC) of 0.81 (95% CI 0.77–0.84). T-SPOT.TB had sensitivity of 0.74 (95% CI 0.71–0.78), specificity of 0.71 (95% CI 0.49–0.86), DOR of 6.96 (95% CI 2.31–20.98), positive LR of 2.53 (95% CI 1.26–5.07), negative LR of 0.36 (95% CI 0.24–0.55), and AUROC of 0.77 (95% CI 0.73–0.80). The specificity seemed lower in the subgroup analyses of studies from high tuberculosis burden counties compared to the studies from low tuberculosis burden.

Conclusion

IGRAs do have insufficient diagnostic performance for SNPTB. However, the tests are still helpful to exclude tuberculosis among patients with low pre-test probability.

Registry: PROSPERO: CRD42021274653.

Value of Fecal Calprotectin Measurement During the Initial Period of Therapeutic Anti-Tubercular Trial

Background/Aims

The diagnosis of intestinal tuberculosis (ITB) is often challenging. Therapeutic anti-tubercular trial (TATT) is sometimes used for the diagnosis of ITB. We aimed to evaluate the changing pattern of fecal calprotectin (FC) levels during TATT in patients with ITB.

Methods

A retrospective review was performed on the data of 39 patients who underwent TATT between September 2015 and November 2018 in five university hospitals in Daegu, South Korea. The analysis was performed for 33 patients with serial FC measurement reports.

Results

The mean age of the participants was 48.8 years. The final diagnosis of ITB was confirmed in 30 patients based on complete mucosal healing on follow-up colonoscopy performed after 2 months of TATT. Before starting TATT, the mean FC level of the ITB patients was 170.2 μg/g (range, 11.5-646.5). It dropped to 25.4 μg/g (range, 11.5-75.3) and then 23.3 μg/g (range, 11.5-172.2) after one and two months of TATT, respectively. The difference in mean FC before and one month after TATT was statistically significant (p<0.001), and FC levels decreased to below 100 μg/g in all patients after one month of TATT.

Conclusions

All ITB patients showed FC decline after only 1 month of TATT, and this finding correlated with complete mucosal healing in the follow-up colonoscopy after 2 months of TATT.

Clinical evaluation of QuantiFERON®-TB Gold Plus directly compared with QuantiFERON®-TB Gold In-Tube and T-Spot®.TB for active pulmonary tuberculosis in the elderly

BACKGROUND

Reduced sensitivity of tuberculosis (TB) interferon-γ release assays (IGRAs) among the elderly has been reported, which is presumably due to diminished immune function. We evaluated the clinical performance of QuantiFERON®-TB Gold plus (QFT-Plus) compared with QuantiFERON®-TB Gold In-Tube (QFT-GIT) and T-Spot®.TB (T-SPOT) in the elderly.

METHODS

Blood samples for all three IGRAs were drawn at the same time from all the participants. Both CD4 and CD8 T-cell counts in patients' peripheral blood were also measured.

RESULTS

A total of 142 active pulmonary TB patients (median age: 84, interquartile range; 76-89 years) were recruited. The sensitivities of the tested IGRAs (excluding invalid/indeterminate cases) were as follows: QFT-Plus, 93.6%; QFT-GIT, 91.4%; and T-SPOT 68.1%. QFT-Plus displayed significantly higher sensitivity than T-SPOT (p < 0.00001). All three IGRAs exhibited the same specificity (100%), as assessed using blood samples from healthy, low TB-risk individuals (n = 118; median age: 39, IQR; 32-47 years). Positivity in 43 active TB patients with CD4 T-cell counts <200/μL, 39 of whom were ≥80 years of age, was as follows: QFT-Plus, 83.7%; QFT-GIT, 74.4%; and T-SPOT, 58.1%. The difference between TB2-TB1 of the QFT-Plus assay was statistically correlated with CD8 but not CD4 T-cell counts in blood (r = 0.193, p = 0.0298).

CONCLUSIONS

QFT-Plus showed high performance in the detection of TB infection in patients irrespective of their advanced age (≥80 years) or lower CD4 counts. QFT-Plus can be useful for the diagnosis of TB infection in all patients, including those who are elderly and/or immunocompromised.

Increased Expression of IL-10 in Peripheral Blood Mononuclear Cells Correlates with Negative Interferon-γ Release Assay Results in Culture-Confirmed Tuberculosis Patients

Introduction

Interferon-γ release assays (IGRAs) can have high false-negative rates for active tuberculosis (TB) cases. Here we investigated factors, including potential anti-inflammatory mechanisms, that contributed to false-negative IGRA results.

Methods

We established two cohorts. In the first cohort, we reviewed IGRA results for confirmed TB cases diagnosed in our hospital in 2018. Cases with false-negative IGRA results were analysed to identify factors contributing to false-negative results. In the second cohort, we prospectively studied IL-10 expression levels in peripheral blood mononuclear cells (PBMCs) of IGRAs-positive and IGRAs-negative TB cases after antigenic stimulation to correlate IL-10 expression with IGRAs results.

Results

Of 1232 culture-confirmed TB cases, 1124 produced true-positive IGRA results and 108 had false-negative IGRA results. Multivariate logistic regression analysis identified glucocorticoid use and extrapulmonary TB as independent risk factors for false-negative IGRA results. Notably, IL-10 expression of the IGRA-negative group was significantly up-regulated as compared to that of the IGRA-positive group. The average cell supernatant IL-10 concentration of the IGRA-negative group was 4.77 pg/mL, a value that was statistically greater than the IGRA-positive group concentration (1.47 pg/mL, P = 0.007). After PBMCs pretreatment with BRD6989 (to enhance IL-10 secretion), average IFN-γ concentrations in cell supernatants from the IGRA-positive group significantly decreased from 59.73 pg/mL to 33.79 pg/mL (P = 0.011). By contrast, addition of AS101 (to inhibit IL-10 secretion) to false-negative group PBMCs led to an increase of average IFN-γ concentration in cell supernatants from 19.01 pg/mL to 45.10 pg/mL (P = 0.030), a result that was inversely correlated with IL-10 concentration.

Conclusion

Our data demonstrate that increased IL-10 secretion by PBMCs is inversely correlated with IGRA assay results in culture-confirmed TB patients. Glucocorticoids use and extrapulmonary TB are significantly associated with false-negative IGRA results. Combination testing to measure IL-10 secretion and IFN-γ release is recommended to improve IGRAs specificity.

Diagnostic accuracy of the interferon-gamma release assay (IGRA) for cases of feline mycobacteriosis

The aim of this study was to evaluate the sensitivity and specificity of the interferon-gamma release assay (IGRA) for diagnosing infections with members of the Mycobacterium (M.) tuberculosis-complex (MTBC) and non-tuberculous mycobacteria (NTM) in domestic cats, and to generate defined feline-specific cut-off values using receiver operating characteristic (ROC) curve analysis to improve test performance. Records of 594 cats that had been tested by IGRA were explored to identify individuals that had a culture and/or polymerase chain reaction (PCR)-confirmed case of mycobacterial disease, and those that had a final diagnosis of non-mycobacterial disease. A total of 117 cats - 80 with mycobacterial disease and 37 diagnosed with a condition other than mycobacteriosis - were identified for further detailed analysis. This population was used to estimate test sensitivity and specificity, as well as likelihood ratios for the IGRA to correctly identify a cat with or without mycobacterial disease. Agreement between IGRA results and culture/PCR using current and proposed new cut-off values was also determined. ROC analysis of defined confirmed infected and non-mycobacterial disease control cats allowed an adjustment of current test cut-offs that increased the overall test sensitivity for MTBC infections from 83.1 % (95 % confidence interval [CI]: 71.5-90.5 %) to 90.2 % (95 % CI: 80.2-95.4%), and M. bovis infection from 43 % (95 % CI: 28.2-60.7%) to 68 % (95 % CI: 51.4-82.1%) while maintaining high test specificity (100 % in both cases). Overall agreement between IGRA results and culture/PCR, while recognising that neither culture nor PCR tests have perfect sensitivity, improved from weak (κ = 0.57) to moderate (κ = 0.71) using new proposed IGRA test cut-off values. Application of these results, based upon the statistical analysis of accumulated test data, can improve the diagnostic performance of the feline IGRA, particularly for identifying infections with M. bovis, without compromising specificity.

Bilateral optic neuritis as a first presentation of lymph node tuberculosis

Tuberculosis (TB) may affect the nervous system in many ways. We describe an immunocompetent teenage girl with lymph node TB who had first presented with bilateral optic neuritis. Detailed history identified features inconsistent with immune-mediated optic neuritis. Several unusual features prompted further investigation, including transient visual obscurations without raised intracranial pressure, prominent disc swelling and absence of laboratory findings to support an immune-mediated cause. Whole body PET/MR imaging identified widespread mediastinal and supraclavicular lymphadenopathy. Despite no known TB contacts, a negative interferon gamma release assay and a normal chest X-ray, a targeted lymph node biopsy confirmed TB.

Readministration of Pembrolizumab after Treatment of Tuberculosis Activated by Initial Pembrolizumab Therapy

Increasing the T-cell immune response to Mycobacterium tuberculosis with an anti-programmed cell death 1 (anti-PD-1) antibody may ultimately have detrimental effects. We present the case of a patient with advanced non-small cell lung cancer who developed active tuberculosis (TB) after initial treatment with pembrolizumab, an anti-PD-1 antibody. Pembrolizumab was resumed after completing anti-TB treatment, and no relapse of TB was observed clinically or radiologically. Checkpoint inhibitor-related pneumonitis (CIP) is first suspected when a pulmonary shadow presents during treatment with an anti-PD-1 antibody. It is sometimes difficult to diagnose CIP using computed tomographic images alone. Careful testing, including bacterial examinations and bronchoscopic biopsy, should be performed.

Awareness and Mental Health of Male Drug Addicts With Tuberculosis During the COVID-19 Pandemic

Introduction: At present, the COVID-19 pandemic remains the most pressing global health issue. Given the significant amount of public awareness, the infection rate and rehabilitation efforts are governed not only by the compliance of transmission mitigation strategies but also by the understanding of coexisting diseases and COVID-19 in patients with chronic infectious diseases. The main goal of this study was to evaluate the differences in demographics, as well as awareness, risk perception, and emotional reactions, among imprisoned drug addicts with and without tuberculosis (TB) regarding their perceptions of and feelings toward the COVID-19 pandemic. The secondary goal of the study was also to measure how the psychological health and nutritional indices of the drug addicts with TB changed during their ongoing rehabilitation. Methods: A total of 265 male drug addicts, 45 of which were positive for TB and another 220 who were negative, were selected as subjects from a mandatory detoxification and rehabilitation center (MDRC). Data were collected through a combination of questionnaires (questions regarding COVID-19 awareness, emotional knowledge and responses, and SCL-90 tests), anthropometric examination, and laboratory blood tests, with which inferential and descriptive statistical analyses were performed. Results: During a period of 1 week in early 2021, the differences in the accuracy of the responses from the questions probing the awareness of COVID-19 symptoms, transmission, susceptible populations, what kind of mask should be worn, and preventive measures between TB addicts to non-TB addicts were 11.11 vs. 60.45%, 57.78 vs. 77.27%, 66.67 vs. 78.64%, 97.98 vs. 97.73%, and 93.33 vs. 65.91%, respectively. In the risk perception and emotional reaction sections of the questionnaire, there was a significant difference in the responses to "What you were more worried about was?" (p < 0.001) and "Alteration in your mood since the outbreak?" (p = 0.002) between the two cohorts. In the section assessing the 10 dimensions of the SCL-90 scale, there were significant differences between the TB addicts and the Chinese norm. In addition, the BMI (21.06 ± 2.65 kg/m²) and total serum protein (77.14 ± 6.12 g/L) levels of the TB addicts were normal, but the serum hemoglobin (117.02 ± 4.97 g/L) and albumin (42.08 ± 1.81 g/L) levels were significantly lower in the TB addicts compared to the norm (p < 0.001). Conclusion: The COVID-19 pandemic we are facing is both an epidemiologic and a psychological crisis. However, while the COVID-19 epidemic will eventually disappear (or become manageable, similar to the flu), the TB epidemic may still persist. To avoid the deleterious consequences of multiple simultaneous epidemics, complementary response measures to COVID-19 and TB can help curb the exacerbation of both situations and, therefore, save lives. Imprisoned drug addicts, especially those with TB, can master relevant knowledge on COVID-19.

Posterior mediastinal nodule diagnosed as a tuberculous granuloma infiltrating into the aorta

Although tuberculous infection rarely results in aortic aneurysm formation or rupture, its precursor lesion has never been identified in cases with tuberculosis. We incidentally encountered a case of a posterior mediastinal nodule with concomitant chest computed tomography (CT) findings of multiple pulmonary micronodular shadows. Since an enlargement of the mediastinal nodule was retrospectively apparent, we considered the lesion as malignant. Enhanced CT showed luminal irregularity in the descending aorta, located adjacent to the nodule, in addition to the disappearance of the fat plane between the lesion and the aorta. We successfully resected the nodule with the aorta under partial cardiopulmonary bypass. Based on the pathological and postoperative bacterial findings, the nodule was diagnosed as a tuberculous granuloma infiltrating into the medial layer of the aorta.

Tuberculosis and COVID-19: Lessons from the Past Viral Outbreaks and Possible Future Outcomes

Background

The threat of contagious infectious diseases is constantly evolving as demographic explosion, travel globalization, and changes in human lifestyle increase the risk of spreading pathogens, leading to accelerated changes in disease landscape. Of particular interest is the aftermath of superimposing viral epidemics (especially SARS-CoV-2) over long-standing diseases, such as tuberculosis (TB), which remains a significant disease for public health worldwide and especially in emerging economies.

Methods and Results

The PubMed electronic database was systematically searched for relevant articles linking TB, influenza, and SARS-CoV viruses and subsequently assessed eligibility according to inclusion criteria. Using a data mining approach, we also queried the COVID-19 Open Research Dataset (CORD-19). We aimed to answer the following questions: What can be learned from other coronavirus outbreaks (focusing on TB patients)? Is coinfection (TB and SARS-CoV-2) more severe? Is there a vaccine for SARS-CoV-2? How does the TB vaccine affect COVID-19? How does one diagnosis affect the other? Discussions. Few essential elements about TB and SARS-CoV coinfections were discussed. First, lessons from past outbreaks (other coronaviruses) and influenza pandemic/seasonal outbreaks have taught the importance of infection control to avoid the severe impact on TB patients. Second, although challenging due to data scarcity, investigating the pathological pathways linking TB and SARS-CoV-2 leads to the idea that their coexistence might yield a more severe clinical evolution. Finally, we addressed the issues of vaccination and diagnostic reliability in the context of coinfection.

Conclusions

Because viral respiratory infections and TB impede the host's immune responses, it can be assumed that their lethal synergism may contribute to more severe clinical evolution. Despite the rapidly growing number of cases, the data needed to predict the impact of the COVID-19 pandemic on patients with latent TB and TB sequelae still lies ahead. The trial is registered with NCT04327206, NCT01829490, and NCT04121494.

Comparison of biochemical parameters and chemokine levels in pleural fluid between patients with anergic and non-anergic tuberculous pleural effusion

Pleural fluid (PF) immune response in anergic tuberculous pleural effusion (TPE) patients is poorly understood. This study aimed to compare PF biochemical parameters and chemokine levels between anergic and non-anergic TPE patients. Chemokine arrays, cytokine measurements, and flow cytometry were performed in 58 patients (TPE [non-anergic (n = 32) and anergic (n = 10)] and malignant pleural effusion (MPE) [n = 16]). PF adenosine deaminase 2 (ADA2) levels were significantly lower in anergic TPE patients than in non-anergic TPE patients (p = 0.048). Among the 40 chemokines tested, PF CCL27 levels were significantly higher in anergic TPE patients than in non-anergic TPE and MPE patients (p < 0.001). The percentage of CD4⁺CCR10⁺T cells in PF was higher in anergic TPE patients than in non-anergic TPE and MPE patients (p = 0.001). We reported here that CCL27/CCR10 interactions might contribute to pathophysiology in anergic TPE. PF CCL27 and CD4⁺CCR10⁺T cells may help in diagnosing TPE in patients with moderate elevation of PF ADA levels.