Frequency of abnormal findings on chest radiograph after positive PPD in children and adolescents in an urban setting in the United States.

BACKGROUND: Chest radiographs (CXR) for tuberculosis (TB) screening in children are valuable in high-burden settings. However, less certain in low prevalence contexts. In the United States, positive PPD is sufficient to treat for "latent" TB, or TB infection in asymptomatic patients. OBJECTIVE: We sought to determine frequency of abnormal CXR findings after a positive purified protein derivative (PPD) test at a tertiary pediatric center in the United States. METHOD: A retrospective evaluation was conducted of patients (0-18 years) with a CXR after a positive PPD (e.g., known exposure, employment, migratory requirements or before immunosuppression) between 2011 and 2021. Clinical information, demographics, and reason for PPD were recorded from health record. CXRs were evaluated using initial report and by a pediatric radiologist with special interest in TB and 8 years of experience. RESULT: Of 485 patients, median [interquartile range (IQR)] age 8.5[3.3-14.4], abnormal CXRs were described in 5 (1%). Most common reasons for PPD included: close contact with someone with TB or with high risk for TB. Most patients 373 (76.9%) received treatment for latent TB, and 111 (22.9%) no treatment. One patient (0.2%) received treatment for active disease. Radiographic findings included isolated lymphadenopathy (n = 2), consolidation (n = 1), pleural fluid/thickening (n = 1) and a patient with lymphadenopathy and a calcified nodule (n = 1). CONCLUSION: In our experience, prevalence of chest radiographs findings for patients with positive PPD was very low. Moreover, no cases of severe disease were seen and those with abnormal findings would not merit treatment change under current WHO guidelines.

Prevalencia de infección tuberculosa latente e incidencia de viraje tuberculínico en contactos escolares mayores de 5 años en la Ciudad Autónoma de Buenos Aires / Prevalence of latent tuberculosis infection and incidence of tuberculin conversion among school contacts older than 5 years in the City of Buenos Aires

Introducción. La tuberculosis continúa siendo un problema frecuente en contextos de vulnerabilidad socioeconómica. El objetivo principal fue establecer la prevalencia de infección latente y viraje tuberculínico en contactos escolares de casos de tuberculosis. Población y métodos. En un área programática del sur de la ciudad, se evaluó la prevalencia de infección y viraje tuberculínico de 691 niñas, niños y adolescentes utilizando la prueba cutánea de tuberculina. Se investigó la asociación entre pérdida de seguimiento por parte del equipo de salud y características demográficas, escolares y asistencia inicial, y se describió el grado de adherencia cuando la quimioprofilaxis con isoniacida fue indicada. Resultados. Según las definiciones consideradas, la prevalencia de infección latente fue entre el 3,4 % (IC95 %: 2,3-5,2) y el 11,6 % (IC95 %: 9,3-14,4) de los 610 contactos con al menos una prueba cutánea aplicada. La incidencia de viraje tuberculínico se encontró entre el 0,3 % y el 6,8 % de los 294 evaluados. La edad mayor de 18 años, la mayor prevalencia de necesidades básicas insatisfechas en la comuna escolar, la pertenencia al turno escolar vespertino, la negatividad en la baciloscopia del caso índice y la ausencia de aplicación de la prueba cutánea inicial se asociaron con pérdida de seguimiento del contacto. Conclusiones. La incidencia de viraje tuberculínico en contactos escolares fue baja. La adherencia a isoniacida continúa siendo limitada. Se identificaron factores asociados con la pérdida de seguimiento de contactos que podrían orientar estrategias necesarias para mejorar este proceso.

Introduction. Tuberculosis continues to be a common problem in settings of socioeconomic vulnerability. Our primary objective was to establish the prevalence of latent infection and tuberculin conversion among school contacts of tuberculosis cases. Population and methods. In a programmatic area in the south of the City of Buenos Aires, the prevalence of latent infection and tuberculin conversion was assessed in 691 children and adolescents using the tuberculin skin test. The association between loss to follow-up by the health care team and the demographic, school, and baseline care characteristics was studied, and the level of adherence when isoniazid chemoprophylaxis was indicated was described. Results. According to established definitions, the prevalence of latent infection was between 3.4% (95% confidence interval [CI]: 2.3­5.2) and 11.6% (95% CI: 9.3­14.4) in the 610 contacts with at least one skin test. The incidence of tuberculin conversion was between 0.3% and 6.8% in the 294 assessed participants. Age older than 18 years, a higher prevalence of unmet basic needs in the school district, attending the afternoon school shift, negative sputum smear results in the index case, and absence of baseline skin test were associated with contact lost to follow-up. Conclusions. The incidence of tuberculin conversion among school contacts was low. Adherence to isoniazid treatment remains limited. Factors associated with loss of contact tracing were identified, which may guide strategies necessary to improve this process.

Positive PPD Test and TB-Ab Misdiagnosed as Tuberculosis Finally Proved as Sarcoidosis by Thoracoscopy: a Case Report.

BACKGROUND: Tuberculosis (TB) is a common infectious disease in developing countries. Tuberculosis and sarcoidosis are difficult to differentiate. We report a case of a patient who was initially misdiagnosed as tuberculosis due to positive tuberculin test (PPD test) and tuberculosis antibody (TB-Ab), which was eventually proven as sarcoidosis by thoracoscopy. METHODS: Appropriate laboratory tests are carried out and a chest CT scan, bronchoscopy, thoracoscopic pathological biopsy were done. RESULTS: Serum sedimentation was increased and tuberculosis antibody was positive. The chest CT scan showed multiple pulmonary nodules in both lungs. The bronchoscopy demonstrated no abnormality. Thoracoscopic pathology showed noncaseating granulomas and acid-fast staining was negative. CONCLUSIONS: When a patient has multiple pulmonary nodules and lymphadenopathy without obvious tuberculosis poisoning symptoms, physicians should pay attention to tuberculosis, sarcoidosis, and lung cancer. Pathology is crucial for the ultimate diagnosis.

Real time endobronchial ultrasound transbronchial needle aspiration for the diagnosis of tuberculous intrathoracic lymphadenopathy: Saudi Arabian Western region experience.

OBJECTIVES: To assess the utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for presumptive tuberculosis (TB) patients with intrathoracic enlarged lymph nodes in a country with low to moderate TB incidence. METHODS: Thirty-one patients with clinical features of TB and intrathoracic lymphadenopathy, who had EBUS-TBNA sampling and final confirmation of intrathoracic TB lymphadenopathy, were retrospectively reviewed over an 8-year period. Routine clinical and laboratory evaluations including computerized tomography scans were performed before the EBUS-TBNA. Sociodemographic characteristics, clinical profile, pathological, and microbiological findings were collected. RESULTS: The EBUS-TBNA confirmed TB diagnosis in 26 (83.9%) subjects with a consistent pathological finding or positive culture of Mycobacterium tuberculosis. Pathological analysis had findings consistent with TB in 25 (80.6%) patients. Culture of the EBUS-TBNA sample was positive for Mycobacterium tuberculosis in 12 (38.7%) patients. Other supportive investigations like purified protein derivative (PPD) skin test was positive in 28 (90.3%) participants. Overall, the sensitivity of the EBUS-TBNA alone was 83.9%. No complications were recorded during the procedure. The EBUS-TBNA aspirate culture positivity was significantly related to having a larger size lymph node (p=0.048) only, while PPD positivity was significantly related to baseline and clinical features of the participants. CONCLUSION: The EBUS-TBNA demonstrated effective utility and safety in the evaluation and diagnosis of intrathoracic TB lymphadenopathy among individuals with compatible symptoms in a country with low-moderate TB-incidence.

The use of natural killer cell activity and PPD test in the prediction of results in intravesical BCG treatment of patients with nonmuscle-invasive bladder cancer.

PURPOSE: To predict the efficacy of intravesical BCG therapy in patients with nonmuscle-invasive bladder tumors (NIBC) by using components of the cellular immune response such as the tuberculin skin test (PPD) and natural killer (NK) activity measurement. METHODS: Ninety-nine patients who were started on intravesical BCG therapy for NIBC were evaluated prospectively. Patients who were included in the intermediate, high, and very high-risk groups according to the EAU NMIBC Scoring System and who had never received intravesical BCG therapy previously were included. The clinical and demographic characteristics of the patients (age, gender, EAU NMBIC risk group, EORTC progression and recurrence scores, CUETO progression and recurrence scores, presence and types of comorbidity) were recorded. NK activity was measured and the PPD test was applied 3 days before the start of intravesical BCG therapy. The results of PPD were measured in millimeters 72 h after the test. RESULTS: PPD values measured before BCG treatment, as an independent variable, were found to be significantly lower in patients with recurrence. A significant correlation was detected between NK activity results obtained before BCG treatment and recurrence after treatment, when the cutoff was 200-500 pg/dl. There was no significant relationship between the time to recurrence and PPD and NKA measurements. CONCLUSION: We conclude that the results of PPD test and NK activity measurement performed before starting intravesical BCG therapy in NIBC may be a marker that can be used to predict the risk of recurrence under treatment.

Dual latent tuberculosis screening with tuberculin skin tests and QuantiFERON-TB assays before TNF-α inhibitor initiation in children in Spain.

Tumor-necrosis-factor-α inhibitors (anti-TNF-α) are associated with an increased risk of tuberculosis (TB) disease, primarily due to reactivation of latent TB infection (LTBI). We assessed the performance of parallel LTBI screening with tuberculin skin test (TST) and QuantiFERON-TB Gold In-Tube assays (QFT-GIT) before anti-TNF-α treatment in children with immune-mediated inflammatory disorders in a low TB-burden setting. We conducted a multicenter cohort study involving 17 pediatric tertiary centers in Spain. LTBI was defined as the presence of a positive TST and/or QFT-GIT result without clinical or radiological signs of TB disease. A total of 270 patients (median age:11.0 years) were included, mainly with rheumatological (55.9%) or inflammatory bowel disease (34.8%). Twelve patients (4.4%) were diagnosed with TB infection at screening (LTBI, n = 11; TB disease, n = 1). Concordance between TST and QFT-GIT results was moderate (TST+/QFT-GIT+, n = 4; TST-/QFT-GIT+, n = 3; TST+/QFT-GIT-, n = 5; kappa coefficient: 0.48, 95% CI: 0.36-0.60). Indeterminate QFT-GIT results occurred in 10 patients (3.7%) and were associated with young age and elevated C-reactive protein concentrations. Eleven of 12 patients with TB infection uneventfully completed standard LTBI or TB treatment. During a median follow-up period of 6.4 years, only 2 patients developed TB disease (incidence density: 130 (95% CI: 20-440) per 100,000 person-years), both probable de novo infections. CONCLUSION: A substantial number of patients were diagnosed with LTBI during screening. The dual strategy identified more cases than either of the tests alone, and test agreement was only moderate. Our data show that in children in a low TB prevalence setting, a dual screening strategy with TST and IGRA before anti-TNF-α treatment is effective. WHAT IS KNOWN: • The optimal screening strategy for latent tuberculosis in children with immune-mediated inflammatory disorders remains uncertain. • Children receiving anti-TNF-α drugs are at increased risk of developing severe tuberculosis disease. WHAT IS NEW: • A dual screening strategy, using TST and an IGRA assay, identified more children with latent tuberculosis than either of the tests alone. • Identification and treatment of latent tuberculosis before initiation of anti-TNF-α therapy averted incident tuberculosis cases.

[Dynamic analysis of tuberculosis specific mononuclear cells in peripheral blood of HIV patients with tuberculosis].

Objective: To evaluate the response of peripheral blood mononuclear cells (PBMCs) in patients with human immunodeficiency virus (HIV) combined with active tuberculosis (TB) to TB-specific antigen stimulation. Methods: From January to December, 2018, individuals infected with both HIV and TB (HIV/TB group) were taken as the study subjects. Individuals infected with HIV alone (HIV group), individuals infected with TB alone (TB group) and healthy people (Health control group, HC group) were taken as the control groups. PBMCs were isolated and stimulated with purified protein derivative of bacillus calmette-guerin (BCG-PPD). The expression of surface molecules in T cells (CD3+, CD4+, CD8+) and monocytes (CD14+) and the percentages of Interferon (IFN)-γ and tumor necrosis factor (TNF)-α were detected by cell surface molecular staining, direct intracellular cytokine staining and flow cytometry (CD3- lymphocytes were mainly B lymphocytes and NK cells). Analysis of non-parametric data was used to compare the data between the two groups, and paired t-test was used to compare the data before and after PPD stimulation in each group. Results: Before PPD stimulation, the percentage of IFN-γ+ CD8+ cells in the peripheral blood of HIV/TB group(mean 0.52%) was significantly lower than that in TB group(mean 0.94%, P=0.010). The TNF-α+cell percentages in CD3+, CD4+, CD8+, or CD14+ cells in the HIV/TB group(mean 19.2%) were significantly lower than those in the HIV group(mean 31.9%, P=0.002). The percentage of TNF-α secreted by monocytes in the HIV group was significantly lower than that in the HC group. The percentages of IFN-γ+ CD8+ and IFN-γ+ CD3- cells in the peripheral blood of the TB group (mean 0.94%) were significantly higher than thoset in the HC group(mean 0.51%, P=0.020), while the percentages of TNF-α+ cells in each subsets of PBMCs were significantly lower than those in the HC group. After PPD stimulation, the percentage of IFN-γ+ CD8+ cells in the HIV/TB group was significantly lower than that in the TB group(P=0.008), and the change was more marked than that before stimulation. The percentage of IFN-γ+ CD8+ cells in the HIV group(mean 0.20%) was lower than that in the HC group (mean 0.52%, P=0.044). The percentage of IFN-γ+ CD3- in the TB group was significantly higher than in the HC group. There were no significant differences in TNF-α+ cell percentages in the 3 groups compared with the control group after PPD stimulation. The percentages of IFN-γ+ CD4+ cells in the HC and the TB groups were significantly increased after PPD stimulation in each group (P=0.002, P=0.001, respectively). However, there were no significant differences of IFN-γ+ CD4+ cell percentages in the HIV/TB group and the HIV group. The percentages of TNF-α production by monocytes were significantly increased after PPD stimulation in all groups. Conclusions: Chronic Mycobacterium tuberculosis (MTB) infection reduced the ability of PBMCs to produce TNF-α. For patients with TB infection, the production of TNF-α was reduced when combined with HIV infection. The capacity of CD8+ and CD3- lymphocytes to produce IFN-γ was increased in TB patients, while the capacity of CD8+ T cells to produce IFN-γ was decreased with co-infection of HIV. Infection of HIV weakened the immune response to MTB infection, which made the clinical diagnosis and treatment of TB more difficult.

Interleukin-18 serum level before and after intralesional immunotherapy with tuberculin purified protein derivative in patients with cutaneous and genital warts.

BACKGROUND: Several studies demonstrated the efficacy of intralesional purified protein derivative (PPD) immunotherapy in warts eradication. Nevertheless, the precise induced immune mechanisms are undetermined. Injected PPD is hypothesized to induce a delayed hypersensitivity reaction associated with cytokines release. Interleukin (IL)-18 has a major role in defense against viral infection via inducing interferon-γ release from T-helper 1 and natural killer (NK) cells. Moreover, IL-18 triggers Fas ligand expression on cytotoxic T cells and NK cells enhancing their cytotoxicity against virally infected cells. AIM: The aim of this study was to assess the role of IL-18 in the response to intralesional PPD injection in patients with warts. METHODS: The study included 25 patients with warts and 25 HCs. Patients underwent PPD skin test, and only patients with positive tests were included and received intralesional PPD injections starting 72 h after the test then every 2 weeks until wart clearance or a maximum of 3 sessions. Serum IL-18 level was measured via enzyme-linked immune-sorbent assay in patients (pre-treatment and 2 weeks after the last injection) and HCs. RESULTS: After 3 sessions of injection, six (24%) patients were designated responders, nine (36%) patients showed partial response, and 10 (40%) patients were designated non-responders. Serum IL-18 level, post-treatment, was significantly higher than pre-treatment level (p = 0.025) and level in HCs (p = 0.036). Furthermore, the post-treatment level was significantly higher in responders than non-responders (p = 0.025). CONCLUSION: IL-18 is probably implicated in the immune mechanisms induced by PPD injection that cause eradication of warts.

BCGΔBCG1419c increased memory CD8+ T cell-associated immunogenicity and mitigated pulmonary inflammation compared with BCG in a model of chronic tuberculosis.

Previously, we reported that a hygromycin resistant version of the BCGΔBCG1419c vaccine candidate reduced tuberculosis (TB) disease in BALB/c, C57BL/6, and B6D2F1 mice infected with Mycobacterium tuberculosis (Mtb) H37Rv. Here, the second-generation version of BCGΔBCG1419c (based on BCG Pasteur ATCC 35734, without antibiotic resistance markers, and a complete deletion of BCG1419c) was compared to its parental BCG for immunogenicity and protective efficacy against the Mtb clinical isolate M2 in C57BL/6 mice. Both BCG and BCGΔBCG1419c induced production of IFN-γ, TNF-α, and/or IL-2 by effector memory (CD44+CD62L-), PPD-specific, CD4+ T cells, and only BCGΔBCG1419c increased effector memory, PPD-specific CD8+ T cell responses in the lungs and spleens compared with unvaccinated mice before challenge. BCGΔBCG1419c increased levels of central memory (CD62L+CD44+) T CD4+ and CD8+ cells compared to those of BCG-vaccinated mice. Both BCG strains elicited Th1-biased antigen-specific polyfunctional effector memory CD4+/CD8+ T cell responses at 10 weeks post-infection, and both vaccines controlled Mtb M2 growth in the lung and spleen. Only BCGΔBCG1419c significantly ameliorated pulmonary inflammation and decreased neutrophil infiltration into the lung compared to BCG-vaccinated and unvaccinated mice. Both BCG strains reduced pulmonary TNF-α, IFN-γ, and IL-10 levels. Taken together, BCGΔBCG1419c increased memory CD8+T cell-associated immunogenicity and mitigated pulmonary inflammation compared with BCG.

Persistent expression of activation markers on Mycobacterium tuberculosis-specific CD4 T cells in smear negative TB patients.

BACKGROUND: T cell activation (HLA-DR, CD-38), proliferation (KI-67), and functional (IFN-γ, TNF-α) markers have recently been shown to be useful in predicting and monitoring anti-TB responses in smear positive TB, but previous research did not characterize the activation and proliferation profiles after therapy of smear negative TB. METHODOLOGY: In this study, we used polychromatic flow cytometry to assess selected PPD-specific T cell markers using fresh PBMC of smear negative and positive pulmonary tuberculosis (PTB) patients, recruited from health facilities in Addis Ababa. RESULT: Levels of activation (HLA-DR, CD38) and proliferation (Ki-67) among total unstimulated CD4 T cells decreased significantly after therapy, particularly at month 6. Similarly, levels of PPD-specific T cell activation markers (HLA-DR, CD-38) were significantly lower in smear positive PTB patients following treatment, whereas a consistent decline in these markers was less apparent among smear negative PTB patients at the sixth month. CONCLUSION: After six months of standard anti-TB therapy, persistent levels of activation of HLA-DR and CD-38 from PPD specific CD4+T cells in this study could indicate that those markers have little value in monitoring and predicting anti-TB treatment response in smear negative pulmonary TB patients in Ethiopian context.

Helminth species dependent effects on Th1 and Th17 cytokines in active tuberculosis patients and healthy community controls.

Despite that the impact of different helminth species is not well explored, the current dogma states that helminths affect the Th1/Th2 balance which in turn affects the risk of tuberculosis (TB) reactivation and severity of disease. We investigated the influence of helminth species on cytokine profiles including IL-17A in TB patients and healthy community controls (CCs). In total, 104 newly diagnosed pulmonary TB patients and 70 HIV negative and QuantiFERON negative CCs in Gondar, Ethiopia were included following helminth screening by stool microscopy. Plasma samples and ex vivo stimulation of peripheral blood mononuclear cells (PBMCs) with purified protein derivative (PPD) and Staphylococcus enterotoxin B (SEB) was used to determine cytokine profiles by cytometric bead array. In CCs, Ascaris lumbricoides or Schistosoma mansoni infections were associated with an impaired Th1-type response (IFN-gamma, IL-6 and TNF-alpha) in PBMCs mainly with SEB stimulations, whereas in TB patients only hookworm infection showed a similar pattern. Among CCs, the IL-17A response in PBMCs stimulated with SEB was higher only for S. mansoni, whereas in TB patients, the elevated systemic IL-17A plasma level was significantly suppressed in hookworm infected TB patients compared to patients without helminth coinfection. Following treatment of TB and helminth infection there was a general decrease in ex vivio IL-10 and TNF-alpha production in unstimulated, PPD or SEB stimulated PBMCs that was the most pronounced and significant in TB patients infected with S. mansoni, whereas the follow-up levels of IFN-gamma and IL-17A was significantly increased only in TB patients without helminth coinfection from PBMCs stimulated mainly with SEB. In summary, in addition to confirming helminth specific effects on the Th1/Th2 response before and after TB treatment, our novel finding is that IL-17A was impaired in helminth infected TB patients especially for hookworm, indicating a helminth species-specific immunoregulatory effect on IL-17A which needs to be further investigated.

Mycobacterium tuberculosis antigen-specific T-cell responses in smear-negative pulmonary tuberculosis patients.

Despite recent improvements in microbial detection, smear-negative TB remains a diagnostic challenge. In this study, we investigated the potential discriminatory role of polychromatic flow cytometry of M. tuberculosis antigen-specific T cells to discriminate smear-negative TB from health controls with or without latent TB infection, and non-TB respiratory illnesses in an endemic setting. A cross-sectional study was conducted on HIV negative, newly diagnosed smear-positive PTB (n = 34), smear-negative/GeneXpert negative PTB (n = 29) patients, non-TB patients with respiratory illness (n = 33) and apparently healthy latent TB infected (n = 30) or non-infected (n = 23) individuals. The expression of activation (HLA-DR, CD-38), proliferation (Ki-67), and functional (IFN-γ, TNF-α) T-cell markers using polychromatic flow cytometry was defined after stimulation with PPD antigens. Sputum samples were collected and processed from all patients for Mtb detection using a concentrated microscopy, LJ/MGIT culture, and RD9 typing by PCR. Our study showed CD4 T cells specific for PPD co-expressed activation/proliferation markers together with induced cytokines IFN-γ or TNF-α were present at substantially higher levels among patients with smear-positive and smear-negative pulmonary TB than among healthy controls and to a lesser extent among patients with non-TB illness. Our study conclude that smear-negative TB can be distinguished from non-TB respiratory illness and healthy controls with a flow cytometric assay for PPD-specific T cells co-expressing activation/proliferation markers and cytokines.

Dominant expansion of CD4+, CD8+ T and NK cells expressing Th1/Tc1/Type 1 cytokines in culture-positive lymph node tuberculosis.

Lymph node culture-positive tuberculosis (LNTB+) is associated with increased mycobacterial antigen-induced pro-inflammatory cytokine production compared to LN culture-negative tuberculosis (LNTB-). However, the frequencies of CD4+, CD8+ T cells and NK cells expressing Th1/Tc1/Type 1 (IFNγ, TNFα, IL-2), Th17/Tc17/Type 17 (IL-17A, IL-17F, IL-22) cytokines and cytotoxic (perforin [PFN], granzyme [GZE] B, CD107a) markers in LNTB+ and LNTB- individuals are not known. Thus, we have studied the unstimulated (UNS) and mycobacterial antigen-induced frequencies of CD4+, CD8+ T and NK cells expressing Th1, Th17 cytokines and cytotoxic markers using flow cytometry. The frequencies of CD4+, CD8+ T and NK cells expressing cytokines and cytotoxic markers were not significantly different between LNTB+ and LNTB- individuals in UNS condition. In contrast, upon Mtb antigen stimulation, LNTB+ individuals are associated with significantly increased frequencies of CD4+ T cells (PPD [IFNγ, TNFα], ESAT-6 PP [IFNγ, TNFα], CFP-10 PP [IFNγ, TNFα, IL-2]), CD8+ T cells (PPD [IFNγ], ESAT-6 PP [IFNγ], CFP-10 PP [TNFα]) and NK cells (PPD [IFNγ, TNFα], ESAT-6 PP [IFNγ, TNFα], CFP-10 PP [TNFα]) expressing Th1/Tc1/Type 1, but not Th17/Tc17/Type 17 cytokines and cytotoxic markers compared to LNTB- individuals. LNTB+ individuals did not show any significant alterations in the frequencies of CD4+, CD8+ T cells and NK cells expressing cytokines and cytotoxic markers compared to LNTB- individuals upon HIV Gag PP and P/I antigen stimulation. Increased frequencies of CD4+, CD8+ T and NK cells expressing Th1/Tc1/Type 1 cytokines among the LNTB+ group indicates that the presence of mycobacteria plays a dominant role in the activation of key correlates of immune protection or induces higher immunopathology.

Combined intralesional injection of tuberculin purified protein derivative plus cryotherapy versus each alone in the treatment of multiple common warts.

Different modalities are used for treatment of common warts, but none of them had been proved the best in achieving complete cure. We aim to compare the effect of cryotherapy, intralesional injection of tuberculin purified protein derivative (PPD) and cryotherapy combined with intralesional injection of tuberculin PPD in the treatment of multiple common warts. This study is a randomized clinical trial in which the patients were randomly divided into three groups; group (A) included 25 patients subjected to cryotherapy, group (B) included 25 patients subjected to intralesional injection of tuberculin PPD and group (C) included 25 patients subjected to cryotherapy plus intralesional injection of tuberculin PPD. All the three groups showed a significant clinical improvement (p < 0.001) with statistically significant difference between cryotherapy group (A) and intralesional injection of tuberculin PPD group (B) (p < 0.001) and between cryotherapy group (A) and cryotherapy plus intralesional injection of tuberculin PPD group (C) (p < 0.001). However, there was no statistically significant difference between both intralesional injection of tuberculin PPD group alone (B) and cryotherapy plus intralesional injection of tuberculin PPD group (C) (p = 0.213). In Conclusion the cryotherapy combined with intralesional injection of PPD and intralesional injection of PPD alone are better than cryotherapy alone in treatment of multiple common warts. However, better response could be reached in combination of both cryotherapy and intralesional PPD with less number of sessions.

Mycobacterium avium subsp. paratuberculosis antigens induce cellular immune responses in cattle without causing reactivity to tuberculin in the tuberculosis skin test.

Mycobacterium avium subspecies paratuberculosis (MAP) causes chronic progressive granulomatous enteritis leading to diarrhea, weight-loss, and eventual death in ruminants. Commercially available vaccine provides only partial protection against MAP infection and can interfere with the use of current diagnostic tests for bovine tuberculosis in cattle. Here, we characterized immune responses in calves to vaccines containing four truncated MAP antigens as a fusion (Ag85A202-347-SOD1-72-Ag85B173-330-74F1-148+669-786), either displayed on protein particles, or expressed as a soluble recombinant MAP (rMAP) fusion protein as well as to commercially available Silirum® vaccine. The rMAP fusion protein elicited the strongest antigen-specific antibody responses to both PPDA and recombinant antigen and strong and long-lasting T-cell immune responses to these antigens, as indicated by increased production of IFN-γ and IL-17A in antigen-stimulated whole blood cultures. The MAP fusion protein particle vaccine induced minimal antibody responses and weak IFN-γ responses but stimulated IL-17A responses to recombinant antigen. The immune response profile of Silirum® vaccine was characterized by weak antibodies and strong IFN-γ and IL-17A responses to PPDA. Transcription analysis on antigen-stimulated leukocytes from cattle vaccinated with rMAP fusion protein showed differential expression of several immune response genes and genes involved in costimulatory signaling, TLR4, TLR2, PTX3, PTGS2, PD-L1, IL1B, IL2, IL6, IL12B, IL17A, IL22, IFNG, CD40, and CD86. Moreover, the expression of several genes of immune pathways correlated with cellular immune responses in the rMAP fusion protein vaccinated group. These genes have key roles in pathways of mycobacterial immunity, including autophagy, manipulation of macrophage-mediated killing, Th17- and regulatory T cells- (Treg) mediated responses. Calves vaccinated with either the rMAP fusion protein or MAP fusion protein particle vaccine did not induce reactivity to PPDA and PPDB in a comparative cervical skin test, whereas Silirum® induced reactivity to these tuberculins in most of the vaccinated animals. Overall, our results suggest that a combination of recombinant MAP antigens in the form of a soluble fusion protein vaccine are capable of inducing strong antigen-specific humoral and a balanced Th1/Th17-cell immune response. These findings, together with the absence of reactivity to tuberculin, suggest this subunit vaccine could provide protective immunity against intracellular MAP infection in cattle without compromising the use of current bovine tuberculosis surveillance test.

The clinical utility of tuberculin skin tests: a single-center experience.

Background: Tuberculin skin test (TST) has played an essential in the diagnosis of latent tuberculosis infection (LTBI) for nearly a century. Objective: This study aimed to investigate the general characteristics of patients tested with TST in a tertiary hospital within two years. Methods: All patients who were evaluated to screen for tuberculosis and received a TST were included. The Mantoux method was used for TST administration. Results: A total of 661 patients, 345 (52.2%) men and 316 (47.8%) women, with a mean age of 43.0 ±15.9 years, were included in the study. Accordingly, TST was performed prior to anti-TNF biological agent therapy for 50% (331) of the participants, for LTBI screening before solid organ and/or hematological stem cell transplantation for 20.4% (135), for screening following contact with tuberculosis for 25.1% (166), for screening of healthcare professionals for 1.1% (7), and medical report for 3.3% (22). 2.7% of the patients who took TST were diagnosed with active tuberculosis (14 with pulmonary tuberculosis and 4 with extrapulmonary tuberculosis). QuantiFERON-TB Gold (QFT) test was performed in 332 (50.2%) patients with anergic TST results. According to TST and QFT test results, 28.3% (187) of the patients were started on tuberculosis prophylaxis. Conclusion: While TST is most performed for LTBI screening prior to biological agent therapy, almost one-fourth of patients taking TST require tuberculosis prophylaxis. On the other hand, about half of the patients require an additional QFT test.

Antecedentes: La prueba de la tuberculina ha jugado un papel fundamental en el diagnóstico de la infección latente por tuberculosis durante casi un siglo. Objetivo: Investigar las características generales de los pacientes a los que se les realizó la prueba de tuberculina en un hospital de tercer nivel. Métodos: Se incluyeron todos los pacientes que fueron incluidos en un tamizaje de tuberculosis mediante la prueba de tuberculina. Se utilizó el método de Mantoux para la administración de esta prueba. Resultados: Se incluyeron en el estudio un total de 661 pacientes, 345 (52.2%) hombres y 316 (47.8%) mujeres, con una edad media de 43.0 ±15.9 años. La prueba de tuberculina se realizó en el 50% (331) de los participantes, antes de la terapia con agentes biológicos anti-TNF; En el 20.4% (135) se hizo la prueba antes del trasplante de órganos sólidos y/o células madre hematológicas; para el 25.1% (166) se realizó tras contacto con la tuberculosis, el 1.1% (7) para tamizaje de los profesionales sanitarios y con informe médico para el 3.3% (22). El 2.7% de los pacientes que se realizaron la prueba de tuberculina fueron diagnosticados con tuberculosis activa (14 pulmonar y 4 extrapulmonar). La prueba QuantiFERON-TB Gold (QFT) se realizó en 332 (50.2 %) pacientes con resultados anérgicos para tuberculina. Según los resultados de las pruebas de tuberculina y QFT, el 28.3% (187) de los pacientes iniciaron profilaxis antituberculosa. Conclusión: Si bien la prueba de tuberculina se realiza comúnmente para la detección de tuberculosis latente antes de la terapia con agentes biológicos, casi una cuarta parte de los pacientes que se les hizo la prueba de tuberculina requieren profilaxis para tuberculosis. Por otro lado, aproximadamente la mitad de los pacientes requieren una prueba QFT adicional.

Diagnosis of goat tuberculosis using tuberculinization and molecular techniques

Tuberculosis is an infectious, chronic, and worldwide disease. It has been known since the beginning of humanity and still negatively influences public health and livestock, especially, in Brazil, in the northeast. Etiologic agents are the mycobacteria of the Mycobacterium tuberculosis complex, which is the most important in mammals' involvement. The state of Bahia has 68.7% of its territory located in the semiarid region and holds the largest goat herd in the country. Goat breeding is a social and economic activity that adds value to this region. Up to the present, data on goat tuberculosis is unknown in this state. Thus, this study seeks data on tuberculosis prevalence in goats in a semiarid region of Bahia by using the comparative tuberculin test and multiplex polymerase chain reaction (PCR). A total of 600 adult animals of both sexes were evaluated. A prevalence of 0.33% (2/600) and 33.33% (1/3) properties were found for positive animals. Each assessed property had a questionnaire to analyze the epidemiological data management and relevant aspects for the disease occurrence. To confirm the positive tuberculin test results, PCR was used to detect and identify the pathogenic mycobacteria involved in the infection. It is concluded that most of the properties performing goat breeding in the region show low technification levels and promote farming between different species. Low prevalence of the disease alerts preventive measures to avoid major proportion situations that could influence the goat breeding in the state.

Characterization of the Infant Immune System and the Influence and Immunogenicity of BCG Vaccination in Infant and Adult Rhesus Macaques.

In many countries where tuberculosis (TB) is endemic, the Bacillus Calmette-Guérin (BCG) vaccine is given as close to birth as possible to protect infants and children from severe forms of TB. However, BCG has variable efficacy and is not as effective against adult pulmonary TB. At present, most animal models used to study novel TB vaccine candidates rely on the use of adult animals. Human studies show that the infant immune system is different to that of an adult. Understanding how the phenotypic profile and functional ability of the immature host immune system compares to that of a mature adult, together with the subsequent BCG immune response, is critical to ensuring that new TB vaccines are tested in the most appropriate models. BCG-specific immune responses were detected in macaques vaccinated within a week of birth from six weeks after immunization indicating that neonatal macaques are able to generate a functional cellular response to the vaccine. However, the responses measured were significantly lower than those typically observed following BCG vaccination in adult rhesus macaques and infant profiles were skewed towards the activation and attraction of macrophages and monocytes and the synthesis in addition to release of pro-inflammatory cytokines such as IL-1, IL-6 and TNF-α. The frequency of specific immune cell populations changed significantly through the first three years of life as the infants developed into young adult macaques. Notably, the CD4:CD8 ratio significantly declined as the macaques aged due to a significant decrease in the proportion of CD4+ T-cells relative to a significant increase in CD8+ T-cells. Also, the frequency of both CD4+ and CD8+ T-cells expressing the memory marker CD95, and memory subset populations including effector memory, central memory and stem cell memory, increased significantly as animals matured. Infant macaques, vaccinated with BCG within a week of birth, possessed a significantly higher frequency of CD14+ classical monocytes and granulocytes which remained different throughout the first three years of life compared to unvaccinated age matched animals. These findings, along with the increase in monokines following vaccination in infants, may provide an insight into the mechanism by which vaccination with BCG is able to provide non-specific immunity against non-mycobacterial organisms.

Immune Responses Following BCG Immunization of Infants in Uganda and United Kingdom Are Similar for Purified Protein Derivative but Differ for Secretory Proteins of Mycobacterium tuberculosis.

Introduction: The immunogenicity of BCG vaccination in infants differs between populations. We hypothesized that prenatal exposure to mycobacterial antigens might explain the differences in immune responses to BCG seen in other studies of infants in Africa and the United Kingdom (UK) and we explored this in birth cohorts in Uganda and the UK. Materials and Methods: Blood samples were obtained from BCG-immunized infants of mothers with (n = 110) and without (n = 121) latent Mycobacterium tuberculosis infection (LTBI) in Uganda and BCG-immunized infants of mothers without LTBI (n = 25) in the UK at 10 and 52 weeks after birth. Cytokine and chemokine responses to PPD were measured to assess responses to BCG immunization, and to ESAT6/CFP10 to assess exposure to or infection with M. tuberculosis or non-tuberculous mycobacteria (NTM) in 6-day whole blood culture supernatants by a 17-plex Luminex assay. Median responses were compared between Ugandan infants (together, and separated by maternal LTBI status) and UK infants. Results: The IFN-γ response to BCG vaccination was similar between Ugandan and UK infants at 10 and 52 weeks. At week 52, TNF production was marginally higher in Ugandan infants, but after adjusting for multiple comparisons this difference was not significant. At weeks 10 and 52, stimulation of blood with ESAT6/CFP10 produced significantly higher IFN-γ, TNF, IL-12p40, IL-1α, IL-1ß, IL-1Ra, IP-10, MIP-1α, MIP-1ß, and GM-CSF in Ugandan compared to UK infants. Stimulation of blood with ESAT6/CFP10 produced significantly higher amounts of IL-8 (p = 0.0001), IL-10 (p = 0.0022), and IL-13 (p = 0.0020) in the UK than in Ugandan infants of mothers without LTBI at week 10, but not at week 52. Conclusions: Immune responses to mycobacterial antigens following BCG immunization are similar for PPD, but differ for ESAT6/CFP10, between infants in Uganda and the UK. Neither maternal LTBI nor infant exposure to or infection with mycobacteria impacts the response to BCG. The observed global differences in immune response to BCG immunization are likely to be due to other causes.

Frequency of anergy in a group of patients with rheumatoid arthritis on immunosuppressive therapy / Frecuencia de anergia en un grupo de pacientes con artritis reumatoide y terapia inmunosupresora

ABSTRACT Background: Tuberculin is the globally accepted delayed cutaneous hypersensitivity test for the diagnosis of latent tuberculosis. The alteration of cellular immunity induced by disease-modifying drugs used in rheumatoid arthritis may give a false negative result, also known as cutaneous anergy. There are no studies that determine the frequency of anergy in patients with rheumatoid arthritis and on immunosuppressive therapy. Objective: To determine the frequency and possible factors associated with cutaneous anergy in a group of patients with rheumatoid arthritis and on immunosuppressive therapy. Methods: Cross-sectional analytical observational study including 100 patients with rheumatoid arthritis on immunosuppressive therapy. They were tested for delayed cutaneous hypersensitivity with tuberculin, and a control test with tetanus toxoid. The non-reactivity of both tests was defined as anergy. Results: The overall frequency of cutaneous anergy was 9% (n = 11). It occurred in 33% of men versus 6% of women. The mean age was 57 years, and 89% were over 50 years-old. Being female behaved as a protective variable for the generation of anergy, OR 0.795 [95% CI, 0.658 - 0.959, P<.05]. All patients with anergy were being treated with corticosteroids, 44% with methotrexate, and 33% with biological therapy. Treatment with moderate to high dose prednisone and biological therapy were independently associated as risk factors for presenting with anergy, OR 1.044 [95% CI, 1.008-1.080 P<.05] and OR 1.096 [95% CI, 1.016-1.182, P<.05], respectively. The overall positivity for tuberculin was 13%. Symptoms associated with disease activation were present in 38% of these. All cases (n= 1) of confirmed active tuberculosis were excluded. Conclusions: The high prevalence of cutaneous anergy in patients with RA in the present study, and the evidence presented here, supports the recommendation of a second diagnostic test (tuberculin booster or Interferon-Gamma Release Assays) for the diagnosis of latent TB in patients with RA on immunosuppressive therapy.

RESUMEN Antecedentes: La tuberculina es la prueba de hipersensibilidad cutánea tardía mundialmente aceptada para el diagnóstico de tuberculosis latente. La alteración de la inmunidad celular inducida por los fármacos modificadores de la enfermedad utilizados en la artritis reumatoide puede dar un resultado falso negativo, también conocido como anergia cutánea. No hay estudios que determinen la frecuencia de anergia en pacientes con artritis reumatoide y terapia inmunosupresora. Objetivo: Determinar la frecuencia y los posibles factores asociados con la anergia cutánea en un grupo de pacientes con artritis reumatoide y terapia inmunosupresora. Métodos: Estudio observacional analítico transversal que incluyó a 100 pacientes con artritis reumatoide con terapia inmunosupresora. Se les realizó una prueba de hipersensibilidad cutánea tardía con tuberculina y una prueba de control con toxoide tetánico. La no reactividad de ambas pruebas se definió como anergia. Resultados: La frecuencia general de anergia cutánea fue del 9% (n = 11). Ocurrió en el 33% de los hombres versus el 6% de las mujeres, la edad promedio fue de 57 anos y el 89% tenía más de 50 anos. El sexo femenino se comportó como una variable protectora para la generación de anergia (OR 0,795; IC 95%: 0,658-0,959; p < 0,05). Todos los pacientes con anergia usaron corticosteroides, el 44% fue tratado con metotrexato y el 33% con terapia biológica. El tratamiento con dosis de moderadas a altas de prednisona y terapia biológica se asoció de manera independiente como factor de riesgo para la presentación de anergia: OR 1,044 (IC 95%: 1,008-1,080; p < 0,05) y OR 1,096 (IC 95%: 1,016-1,182; p < 0,05), respectivamente. La positividad general para la tuberculina fue del 13%. Los síntomas asociados con la activación de la enfermedad estaban presentes en el 38% de ellos. Se excluyeron todos los casos de tuberculosis activa confirmada (n = 1). Conclusiones: La alta prevalencia de anergia cutánea en pacientes con artritis reumatoide en el presente estudio y la evidencia presentada respaldan la recomendación de una segunda prueba de diagnóstico (refuerzo de tuberculina o IGRA) para el diagnóstico de tuberculosis latente en pacientes con artritis reumatoide y terapia inmunosupresora.