Tuberculin skin test repetition after TNF-α inhibitors in patients with chronic inflammatory arthritis: a long-term retrospective cohort in endemic area.

OBJECTIVES: To evaluate the tuberculin skin test (TST) conversion in chronic inflammatory arthropathies (CIA) patients on TNFα inhibitors (TNFi) and without previous latent tuberculosis infection (LTBI) treatment. METHODS: Patients with rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) with negative LTBI were retrospectively evaluated for TST conversion and active tuberculosis (TB) after six months of exposition to TNFi. Two groups were compared: patients who repeated TST (TST-repetition) during the follow-up and patients who did not (non-TST-repetition). RESULTS: A total of 355 CIA patients on TNFi were screened and 138 (38.9%) did not fulfill the inclusion criteria. Of the remaining 217 CIA patients, 81 (37.3%) repeated TST during TNFi treatment. TST conversion rate was observed in 18 (22.2%) patients without significant differences among CIA (p = 0.578). The number of TB cases was low (n = 10; 4.6%) and was similar in TST-repetition and non-TST-repetition groups [2 (2.5%) vs. 8 (5.9%), p = 0.328]. Of note, 30% of active TB occurred early (6-12 months of TNFi exposure) and the median (full range) time to incident TB was 1.3 (0.6-10.6) years, whereas the median (full range) time to TST repetition was later [3.3 (0.5-13.4) years]. The incidence of active TB was lower among RA patients than AS patients [342 (95% CI 41 - 1446) vs. 1.454 (95% CI 594-2993)/100,000 patient-years, p = 0.049]. CONCLUSION: These results indicate that TST repetition is associated with a high conversion rate, suggesting the need for recommended treatment. The delayed repetition of TST and low number of active TB cases hampered the evaluation of this strategy effectiveness to prevent active infection. Larger studies with systematic repetition patterns are necessary. In addition, the study highlights the need for a greater surveillance for TB in AS patients.

Limited usefulness of the IS6110 touchdown-PCR in blood for tuberculin skin test false-negative cattle with serological response to Mycobacterium bovis.

Ante-mortem diagnosis of bovine tuberculosis (bTB) is based mainly on the tuberculin skin test (TST) and the ɣ-IFN release assay (IGRA). Some infected animals escape screening tests, thus, limit herd sanitation. Previous reports have suggested a predominant pattern of multi-organ lesions attributable to Mycobacterium bovis (the causative agent of bTB) bacteraemia. A case-control study was conducted to investigate blood PCR as an alternative tool for improving ante-mortem detection of TST false-negative bovines. Cases comprised 70 TST false-negative bovines (cases), which were serology positive, and controls included 81 TST positive bovines; all of them confirmed as infected with M. bovis. Detection of the IS6110 target through touchdown blood-PCR (IS6110 TD-PCR) was performed. The positivity of the blood-PCR was 27.2% in the control group. This performance was similar to the 15% obtained among cases (p = 0.134). Most cases identified by the IS6110 TD-PCR exhibited focalized lesions (p = 0.002). Results demonstrated that blood-PCR could detect TST false-negative cattle, even if they are negative for IGRA. Considering that cases exhibited humoral response to M. bovis, further studies conducted in a pre-serological stage could provide evidence about the real contribution of the technique in herds.

US Postarrival Evaluation of Immigrant and Refugee Children with Latent Tuberculosis Infection Diagnosed Overseas, 2007-2019.

OBJECTIVE: To assess outcomes from the US postarrival evaluation of newly arrived immigrant and refugee children aged 2-14 years who were diagnosed with latent tuberculosis infection (LTBI) during a required overseas medical examination. STUDY DESIGN: We compared overseas and US interferon-γ release assay (IGRA)/tuberculin skin test (TST) results and LTBI diagnosis; assessed postarrival LTBI treatment initiation and completion; and evaluated the impact of switching from TST to IGRA to detect Mycobacterium tuberculosis infection overseas. RESULTS: In total, 73 014 children were diagnosed with LTBI overseas and arrived in the US during 2007-2019. In the US, 45 939 (62.9%) completed, and 1985 (2.7%) initiated but did not complete a postarrival evaluation. Among these 47 924 children, 30 360 (63.4%) were retested for M tuberculosis infection. For 17 996 children with a positive overseas TST, 73.8% were negative when retested by IGRA. For 1051 children with a positive overseas IGRA, 58.0% were negative when retested by IGRA. Overall, among children who completed a postarrival evaluation, 18 544 (40.4%) were evaluated as having no evidence of TB infection, and 25 919 (56.4%) had their overseas LTBI diagnosis confirmed. Among the latter, 17 229 (66.5%) initiated and 9185 (35.4%) completed LTBI treatment. CONCLUSIONS: Requiring IGRA testing overseas could more effectively identify children who will benefit from LTBI treatment. However, IGRA reversions may occur, highlighting the need for individualized assessment for risk of infection, progression, and poor outcome when making diagnostic and treatment decisions. Strategies are needed to increase the proportions receiving a postarrival evaluation and completing LTBI treatment.

Prevalence of latent tuberculosis in patients with hematological neoplasms in a cancer referral hospital in Mexico City.

OBJECTIVE: To determine the prevalence of Latent Tuberculosis in patients with hematological neoplasms at the Instituto Nacional de Cancerología in Mexico City using the Tuberculin skin test (TST). METHODS: This retrospective study included all patients with a recent diagnosis of hematological neoplasms who were admitted for treatment from 2017 to 2018 and who were screened for latent tuberculosis with the TST. The prevalence of latent tuberculosis in this group, tolerance and therapeutic adherence in treated patients are described. RESULTS: The files of 446 patients with hematological malignancy who had a TST were reviewed. The prevalence of latent tuberculosis was 31.2% (n = 139). Ninety-three patients received isoniazid, 15.1% had some adverse reactions, but only 4 (4.3%) had to discontinue treatment. Two patients with latent tuberculosis under treatment with Isoniazid reactivated tuberculosis infection. CONCLUSIONS: The prevalence in our study was within the range of other similar Mexican populations. Isoniazid treatment had an adequate tolerance and adherence. Longer follow-up could offer more information on the risk of reactivation in both groups.

Interferon-Gamma Release Assays Differentiate between Mycobacterium avium Complex and Tuberculous Lymphadenitis in Children.

OBJECTIVES: To assess the performance of interferon-gamma release assays (IGRAs) in the differential diagnosis between Mycobacterium avium complex (MAC) and tuberculosis (TB) in children affected with subacute/chronic submandibular/cervical lymphadenitis. STUDY DESIGN: Multicenter observational study comparing children with microbiologically confirmed MAC lymphadenitis from the European NontuberculouS MycoBacterial Lymphadenitis in childrEn study with children with TB lymphadenitis from the Spanish Network for the Study of Pediatric TB database. RESULTS: Overall, 78 patients with MAC and 34 with TB lymphadenitis were included. Among MAC cases, 44 out of 74 (59.5%) had positive tuberculin skin test (TST) results at the 5-mm cut-off, compared with 32 out of 33 (97%) TB cases (P < .001); at the 10-mm cut-off TST results were positive in 23 out of 74 (31.1%) vs 26 out of 31 (83.9%), respectively (P < .001). IGRA results were positive in only 1 out of 32 (3.1%) patients with MAC who had undergone IGRA testing, compared with 21 out of 23 (91.3%) TB cases (P < .001). Agreement between TST and IGRA results was poor in MAC (23.3%; κ = 0.017), but good in TB cases (95.6%; κ = 0.646). IGRAs had a specificity of 96.9% (95% CI 84.3%-99.8%), positive predictive value of 95.4% (95% CI 78.2%-99.8%), and negative predictive value of 93.9% (95% CI 80.4%-98.9%) for TB lymphadenitis. CONCLUSIONS: In contrast to TST, IGRAs have high specificity, negative predictive value, and positive predictive value for TB lymphadenitis in children with subacute/chronic lymphadenopathy, and consequently can help to discriminate between TB and MAC disease. Therefore, IGRAs are useful tools in the diagnostic work-up of children with lymphadenopathy, particularly when culture and polymerase chain reaction results are negative.

Tuberculosis Skin Test Screening in the National Tuberculosis Program of Trinidad and Tobago.

Globally, a quarter of the population is infected with tuberculosis (TB), caused by Mycobacterium tuberculosis. About 5-10% of latent TB infections (LTBI) progress to active disease during the lifetime. Prevention of TB and treating LTBI is a critical component of the World Health Organization's (WHO) End TB Strategy. This study aims to examine the screening practices for prevention and treatment employed by the National Tuberculosis Program of Trinidad and Tobago in comparison to the WHO's standard guidelines. A cross-sectional retrospective study was conducted from the TB registers (2018-2019) for persons aged 18 years and above with recorded tuberculin skin test reactions (TST). Bivariate comparisons for categorical variables were made using Chi-square or Fisher's exact test. Binary logistic regression was used for exploring predictors of TST positivity with adjustment for demographic confounders in multivariable models. Of the total 1972 eligible entries studied, 384 (19.4%) individuals were tested positive with TST. TB contact screening (aOR 2.49; 95% CI 1.65, 3.75) and Bacillus Calmette-Guerin (BCG) vaccination status (aOR 1.66; 95% CI, 1.24 to 2.22) were associated with a positive TST reaction, whereas, preplacement screening failed to show such association when compared to those screened as suspect cases. The findings suggest that TB contact screening and positive BCG vaccination status are associated with TST positivity independent of age and gender.

Current Practices in Ocular Tuberculosis: A Survey of Brazilian Specialists.

Purpose: To describe the approach of Brazilian specialists in the diagnosis and treatment of tuberculosis-associated uveitis (TBU).Methods: Members of the Brazilian Uveitis Society received an electronic invitation to participate in an online questionnaire.Results: Of the 169 invited specialists, 78 answered the questionnaire. Specialists evaluated 5.6 patients with TBU annually. Tuberculin skin test (TST, 81%) was primarily used for diagnosis. Patients with presumed TBU should always be tested for syphilis and HIV according to 51 (88%) and 47 (81%) of respondents, respectively. Chest computed tomography (CT, 72%) was preferable to chest radiography (CXR) for diagnosis. A positive TST (81%) and CXR (60%) were the main indicators of anti-tuberculous therapy, with 34%, 39%, and 14% of specialists treating for 6, 9, and 12 months, respectively.Conclusions: TST remains the preferred method for TBU diagnosis and prompt treatment by Brazilian specialists, though there is no consensus regarding disease treatment and management.

Polymorphisms in interferon pathway genes and risk of Mycobacterium tuberculosis infection in contacts of tuberculosis cases in Brazil.

BACKGROUND: Host genetic polymorphisms may be important in determining susceptibility to Mycobacterium tuberculosis (Mtb) infection, but their role is not fully understood. Detection of microbial DNA and activation of type I interferon (IFN) pathways regulate macrophage responses to Mtb infection. METHODS: We examined whether seven candidate gene SNPs were associated with tuberculin skin test (TST) positivity in close contacts of microbiologically confirmed pulmonary TB patients in Brazil. Independent associations with TST positivity were tested using multivariable logistic regression (using genotypes and clinical variables) and genetic models. RESULTS: Among 482 contacts of 145 TB index cases, 296 contacts were TST positive. Multivariable regression analysis adjusted for population admixture, age, family relatedness, sex and clinical variables related to increased TB risk demonstrated that SNPs in PYHIN1-IFI16-AIM2 rs1101998 (adjusted OR [aOR]: 3.72; 95%CI=1.15-12.0; p=0.028) and in PYHIN1-IFI16-AIM2 rs1633256 (aOR=24.84; 95%CI=2.26-272.95; p=0.009) were associated with TST positivity in a recessive model. Furthermore, an IRF7 polymorphism (rs11246213) was associated with reduced odds of TST positivity in a dominant model (aOR: 0.50, 95%CI: 0.26-0.93; p=0.029). CONCLUSIONS: Polymorphisms in PYHIN1-IFI16-AIM2 rs1633256, rs1101998 and in IRF7 rs11246213 were associated with altered susceptibility to Mtb infection in this Brazilian cohort.

Ankylosing spondylitis and psoriatic arthritis: revisiting screening of latent tuberculosis infection and its follow-up during anti-tumor necrosis factor therapy in an endemic area

OBJECTIVES: To retrospectively evaluate the performance and distinctive pattern of latent tuberculosis (TB) infection (LTBI) screening and treatment in patients with ankylosing spondylitis (AS) and psoriatic arthritis (PsA) under anti-tumor necrosis factor (TNF) therapy and determine the relevance of re-exposure and other risk factors for TB development. METHODS: A total of 135 and 83 patients with AS and PsA, respectively, were evaluated for LTBI treatment before receiving anti-TNF drugs via the tuberculin skin test (TST), chest radiography, and TB exposure history assessment. All subjects were evaluated for TB infection at 3-month intervals. RESULTS: The patients with AS were more often treated for LTBI than were those with PsA (42% versus 30%, p=0.043). The former also presented a higher frequency of TST positivity (93% versus 64%, p=0.002), although they had a lower frequency of exposure history (18% versus 52%, p=0.027) and previous TB (0.7% versus 6%, p=0.03). During follow-up [median, 5.8 years; interquartile range (1QR), 2.2-9.0 years], 11/218 (5%) patients developed active TB (AS, n=7; PsA, n=4). TB re-exposure was the main cause in seven patients (64%) after 12 months of therapy (median, 21.9 months; IQR, 14.2-42.8 months) and five LTBI-negative patients. TB was identified within the first year in four patients (36.3%) (median, 5.3 months; IQR, 1.2-8.8 months), two of whom were LTBI-positive. There was no difference in the TB-free survival according to the anti-TNF drug type/class; neither synthetic drug nor prednisone use was related to TB occurrence (p>0.05). CONCLUSION: Known re-exposure is the most critical factor for incident TB cases in spondyloarthritis. There are also some distinct features in AS and PsA LTBI screening, considering the higher frequency of LTBI and TST positivities in patients with AS. Annual risk reassessment taking into consideration these peculiar features and including the TST should be recommended for patients in endemic countries.

Incidence of tuberculosis infection in spondyloarthritis patients treated with biological and conventional disease-modifying anti-rheumatic drugs in an endemic area

Introduction: Registries of spondyloarthritis (SpA) patients' follow-up provided evidence that tumor necrosis factor inhibitors (TNFi) increase the incidence of active tuberculosis infection (TB). However, most of these registries are from low burden TB areas. Few studies evaluated the safety of biologic agents in TB endemic areas. This study compares the TB incidence rate (TB IR) in anti-TNF-naïve and anti-TNF-experienced subjects with SpA in a high TB incidence setting.Methods: In this retrospective cohort study, medical records from patients attending a SpA clinic during 13 years (2004 to 2016) in a university hospital were reviewed. The TB IR was calculated and expressed as number of events per 105 patients/year; the incidence rate ratio (IRR) associated with the use of TNFi was calculated.Results: A total of 277 patients, 173 anti-TNF-naïve and 104 anti-TNF-experienced subjects, were evaluated; 35.7% (N = 35) of patients who were prescribed an anti-TNF drug were diagnosed with latent tuberculosis infection (LTBI). Total follow-up time (person-years) was 1667.8 for anti-TNF-naïve and 394.9 for anti-TNF-experienced patients. TB IR (95% CI) was 299.8 (37.4-562.2) for anti-TNF naïve and 1012.9 (25.3-2000.5) for anti-TNF experienced subjects. The IRR associated with the use of TNFi was 10.4 (2.3- 47.9).Conclusions: In this high TB incidence setting, SpA patients exposed to anti-TNF therapy had a higher incidence of TB compared to anti-TNF-naïve subjects, although the TB incidence in the control group was significant.(AU)

Superiority of Interferon Gamma Assay Over Tuberculin Skin Test for Latent Tuberculosis in Inflammatory Bowel Disease Patients in Brazil.

BACKGROUND AND AIMS: To compare tuberculin skin test (TST) and interferon gamma release assay (IGRA) in the screening of LTBI among patients with inflammatory bowel disease (IBD) in an endemic area for tuberculosis, to evaluate the need for repeating tests during anti-TNFα, therapy, and to check whether the results may be affected by immunosuppression. METHODS: A cross-sectional study of 110 IBD patients and 64 controls was conducted in Rio de Janeiro, Brazil. The TST was administered after the Quantiferon(®)-TB Gold In-tube test was performed. RESULTS: TST and IGRA agreement was poor regarding diagnosis (kappa: control = 0.318; UC = 0.202; and CD = - 0.093), anti-TNFα therapy (kappa: with anti-TNFα = 0.150; w/o anti-TNFα = - 0.123), and immunosuppressive therapy (IST) (kappa: with IS = - 0.088; w/o IS = 0.146). Indeterminate IGRA was reported in four CD patients on IST. Follow-up tests after anti-TNFα identified conversion in 8.62% using TST and 20.0% using IGRA. Considering IGRA as a criterion standard, TST showed low sensitivity (19.05%) and positive predictive value (PPV) (21.05%). LTBI detection remarkably improved when IGRA was added to TST (sensitivity of 80.95% and PPV of 53.13%). Results were particularly relevant among CD patients where rates started from zero to reach sensitivity and PPV of more than 60%. CONCLUSION: IGRA alone was more effective to detect LTBI than TST alone and had an overall remarkable added value as an add-on sequential test, particularly in CD patients. While cost-effectiveness of these strategies remains to be evaluated, IGRA appears to be justified in CD prior to and during anti-TNFα therapy, where tuberculosis is endemic.

Polymorphisms in TLR4 and TNFA and Risk of Mycobacterium tuberculosis Infection and Development of Active Disease in Contacts of Tuberculosis Cases in Brazil: A Prospective Cohort Study.

BACKGROUND: The role of genetic polymorphisms in latent tuberculosis (TB) infection and progression to active TB is not fully understood. METHODS: We tested the single-nucleotide polymorphisms (SNPs) rs5743708 (TLR2), rs4986791 (TLR4), rs361525 (TNFA), rs2430561 (IFNG) rs1143627 (IL1B) as risk factors for tuberculin skin test (TST) conversion or development of active TB in contacts of active TB cases. Contacts of microbiologically confirmed pulmonary TB cases were initially screened for longitudinal evaluation up to 24 months, with clinical examination and serial TST, between 1998 and 2004 at a referral center in Brazil. Data and biospecimens were collected from 526 individuals who were contacts of 177 active TB index cases. TST conversion was defined as induration ≥5 mm after a negative TST result (0 mm) at baseline or month 4 visit. Independent associations were tested using logistic regression models. RESULTS: Among the 526 contacts, 60 had TST conversion and 44 developed active TB during follow-up. Multivariable regression analysis demonstrated that male sex (odds ratio [OR]: 2.3, 95% confidence interval [CI]: 1.1-4.6), as well as SNPs in TLR4 genes (OR: 62.8, 95% CI: 7.5-525.3) and TNFA (OR: 4.2, 95% CI: 1.9-9.5) were independently associated with TST conversion. Moreover, a positive TST at baseline (OR: 4.7, 95% CI: 2.3-9.7) and SNPs in TLR4 (OR: 6.5, 95% CI: 1.1-36.7) and TNFA (OR: 12.4, 95% CI:5.1-30.1) were independently associated with incident TB. CONCLUSIONS: SNPs in TLR4 and TNFA predicted both TST conversion and active TB among contacts of TB cases in Brazil.

Latent tuberculosis infection in patients with rheumatic diseases / Infecção latente por tuberculose em pacientes com doenças reumatológicas

ABSTRACT Most people infected by Mycobacterium tuberculosis (Mtb) do not have any signs or disease symptoms, a condition known as latent tuberculosis infection (LTBI). The introduction of biological agents, mainly tumor necrosis factor (TNF) inhibitors, for the treatment of immune-mediated diseases such as Rheumatoid Arthritis (RA) and other rheumatic diseases, increased the risk of reactivation of LTBI, leading to development of active TB. Thus, this review will approach the aspects related to LTBI in patients with rheumatologic diseases, especially those using iTNF drugs. For this purpose it will be considered the definition and prevalence of LTBI, mechanisms associated with diseases and medications in use, criteria for screening, diagnosis and treatment. Considering that reactivation of LTBI accounts for a large proportion of the incidence of active TB, adequate diagnosis and treatment are crucial, especially in high-risk groups such as patients with rheumatologic diseases.

RESUMO A maioria das pessoas infectadas por Mycobacterium tuberculosis (Mtb) não possui sinais ou sintomas da doença, quadro conhecido como infecção latente por tuberculose (ILTB). A introdução de agentes biológicos, sobretudo inibidores do fator de necrose tumoral (iTNF), para o tratamento de doenças imunomediadas, como artrite reumatoide (AR) e outras doenças reumatológicas, aumentou o risco de reativação de ILTB, levando ao desenvolvimento de tuberculose (TB) ativa. Assim, esta revisão abordará os aspectos relacionados à ILTB em pacientes com doenças reumatológicas, especialmente naqueles em uso de medicamentos iTNF. Para tanto, serão considerados a definição e a prevalência de ILTB, os mecanismos associados às doenças e às medicações em uso, bem como os critérios para rastreamento, diagnóstico e tratamento da ILTB. Como a reativação da ILTB é responsável pela grande proporção de casos de TB ativa, o diagnóstico e o tratamento adequados são cruciais, principalmente em grupos de alto risco, como os pacientes com doenças reumatológicas.

Diagnostics of tuberculosis and differentiation of nonspecific tuberculin reactions in animals

Tuberculosis is a serious disease of humans and animals, caused by bacteria of the Mycobacterium genus. This leads to complications in the life of the sick person, and subsequently to death. The cattle, who have been diagnosed with this bacterium, are usually sent to the slaughter, with the result that their livestock is reduced. Mycobacteriosis is also a disease, after determining which cattle are most often sent to slaughter. Such a reduction in livestock numbers has a negative effect on the economy. Of the 300 samples from the animals, 25 cultures of atypical bacteria responding to tuberculin were isolated. A series of tests - intravenous tuberculin test, ophthalmic test, palpebral test, "ZhAT" test, showed that most of the tuberculosis changes in cattle were found in regional lymph nodes more often than in internal organs. In healthy for tuberculosis cows, at the age of 4-9 years, seasonal nonspecific sensitivity to tuberculin is observed. Implementation of the developed express method of glutaraldehyde test on farms in healthy tuberculosis will speed up the diagnosis of tuberculosis and mycobacteriosis in animals that reacted to tuberculin and will exclude short-term nonspecific sensitization of their organism to tuberculin. The introduction of this methodology can be used to diagnose and clearly differentiate the diagnoses of "tuberculosis" and "mycobacteriosis" in cattle. This will cure part of the livestock and reduce the amount of slaughter.(AU)

Diagnostics of tuberculosis and differentiation of nonspecific tuberculin reactions in animals

Abstract Tuberculosis is a serious disease of humans and animals, caused by bacteria of the Mycobacterium genus. This leads to complications in the life of the sick person, and subsequently to death. The cattle, who have been diagnosed with this bacterium, are usually sent to the slaughter, with the result that their livestock is reduced. Mycobacteriosis is also a disease, after determining which cattle are most often sent to slaughter. Such a reduction in livestock numbers has a negative effect on the economy. Of the 300 samples from the animals, 25 cultures of atypical bacteria responding to tuberculin were isolated. A series of tests - intravenous tuberculin test, ophthalmic test, palpebral test, "ZhAT" test, showed that most of the tuberculosis changes in cattle were found in regional lymph nodes more often than in internal organs. In healthy for tuberculosis cows, at the age of 4-9 years, seasonal nonspecific sensitivity to tuberculin is observed. Implementation of the developed express method of glutaraldehyde test on farms in healthy tuberculosis will speed up the diagnosis of tuberculosis and mycobacteriosis in animals that reacted to tuberculin and will exclude short-term nonspecific sensitization of their organism to tuberculin. The introduction of this methodology can be used to diagnose and clearly differentiate the diagnoses of "tuberculosis" and "mycobacteriosis" in cattle. This will cure part of the livestock and reduce the amount of slaughter.

Diagnostics of tuberculosis and differentiation of nonspecific tuberculin reactions in animals.

Tuberculosis is a serious disease of humans and animals, caused by bacteria of the Mycobacterium genus. This leads to complications in the life of the sick person, and subsequently to death. The cattle, who have been diagnosed with this bacterium, are usually sent to the slaughter, with the result that their livestock is reduced. Mycobacteriosis is also a disease, after determining which cattle are most often sent to slaughter. Such a reduction in livestock numbers has a negative effect on the economy. Of the 300 samples from the animals, 25 cultures of atypical bacteria responding to tuberculin were isolated. A series of tests - intravenous tuberculin test, ophthalmic test, palpebral test, "ZhAT" test, showed that most of the tuberculosis changes in cattle were found in regional lymph nodes more often than in internal organs. In healthy for tuberculosis cows, at the age of 4-9 years, seasonal nonspecific sensitivity to tuberculin is observed. Implementation of the developed express method of glutaraldehyde test on farms in healthy tuberculosis will speed up the diagnosis of tuberculosis and mycobacteriosis in animals that reacted to tuberculin and will exclude short-term nonspecific sensitization of their organism to tuberculin. The introduction of this methodology can be used to diagnose and clearly differentiate the diagnoses of "tuberculosis" and "mycobacteriosis" in cattle. This will cure part of the livestock and reduce the amount of slaughter.

Diagnostics of tuberculosis and differentiation of nonspecific tuberculin reactions in animals

Abstract Tuberculosis is a serious disease of humans and animals, caused by bacteria of the Mycobacterium genus. This leads to complications in the life of the sick person, and subsequently to death. The cattle, who have been diagnosed with this bacterium, are usually sent to the slaughter, with the result that their livestock is reduced. Mycobacteriosis is also a disease, after determining which cattle are most often sent to slaughter. Such a reduction in livestock numbers has a negative effect on the economy. Of the 300 samples from the animals, 25 cultures of atypical bacteria responding to tuberculin were isolated. A series of tests - intravenous tuberculin test, ophthalmic test, palpebral test, "ZhAT" test, showed that most of the tuberculosis changes in cattle were found in regional lymph nodes more often than in internal organs. In healthy for tuberculosis cows, at the age of 4-9 years, seasonal nonspecific sensitivity to tuberculin is observed. Implementation of the developed express method of glutaraldehyde test on farms in healthy tuberculosis will speed up the diagnosis of tuberculosis and mycobacteriosis in animals that reacted to tuberculin and will exclude short-term nonspecific sensitization of their organism to tuberculin. The introduction of this methodology can be used to diagnose and clearly differentiate the diagnoses of "tuberculosis" and "mycobacteriosis" in cattle. This will cure part of the livestock and reduce the amount of slaughter.

Latent tuberculosis infection and tuberculosis in patients with rheumatic diseases treated with anti-tumor necrosis factor agents.

The introduction of biological agents, especially the tumor necrosis factor inhibitors (anti-TNF), for the treatment of rheumatic diseases increased the risk of developing tuberculosis (TB). Screening for latent TB infection (LTBI) is strongly recommended before starting therapy with anti-TNF agents. The objective of this study was to identify the prevalence of LTBI and TB among patients with rheumatic diseases on anti-TNF agents. This is a cross-sectional study. The electronic medical records of all adult patients (≥18 years old) undergoing anti-TNF treatment were reviewed. Every patient underwent tuberculin skin test (TST) before starting anti-TNF treatment. In total, 176 patients were included; the mean age was 51.9 ± 12.4 years, 34.7% were males, and 90.9% were white. The underlying diseases were rheumatoid arthritis (RA) in 50.6% (N = 89), ankylosing spondylitis (AS) in 27.8% (N = 49), and psoriatic arthritis (PsA) in 17.6% (N = 31). The prevalence of positive TST was 29.5%. Household contact with TB was significantly associated with a positive TST (p = 0.020). RA patients had lower TST reactions than AS patients (p = 0.022). There were six cases of TB (3.4%) diagnosed during anti-TNF therapy. We demonstrated a high prevalence of positive TST (29.5%) among patients with rheumatic diseases in a region with high TB prevalence. Our data corroborates the ACR's recommendation that patients who live in high TB incidence settings should be tested annually for LTBI.

Detection of latent tuberculosis infection among migrant farmworkers along the US-Mexico border.

BACKGROUND: Migrant farmworkers are among the highest-risk populations for latent TB infection (LTBI) in the United States with numerous barriers to healthcare access and increased vulnerability to infectious diseases. LTBI is usually diagnosed on the border using the tuberculin skin test (TST). QuantiFERON-TB Gold In-Tube (QFT-GIT) also measures immune response against specific Mycobacterium tuberculosis antigens. The objective of this study is to assess the comparability of TST and QFT-GIT to detect LTBI among migrant farmworkers on the border, as well as to examine the effects of various demographic and clinical factors on test positivity. METHODS: Participants were recruited using mobile clinics on the San Luis US-Mexico border and tested with QFT-GIT and TST. Demographic profiles and clinical histories were collected. Kappa coefficients assessed agreement between TST and QFT-GIT using various assay cutoffs. Logistic regression examined factors associated with positive TST or QFT-GIT results. RESULTS: Of 109 participants, 59 of 108 (55 %) were either TST (24/71, 34 %) or QFT-GIT (52/106, 50 %) positive. Concordance between TST and QFT-GIT was fair (71 % agreement, ĸ = 0.38, 95 % CI: 0.15, 0.61). Factors associated with LTBI positivity included smoking (OR = 1.26, 95 % CI-1.01-1.58) and diabetes/high blood sugar (OR = 0.70, 95 % CI = 0.51-0.98). DISCUSSION: Test concordance between the two tests was fair, with numerous discordant results observed. Greater proportion of positives detected using QFT-GIT may help avoid LTBI under-diagnosis. Assessment of LTBI status on the border provides evidence whether QFT-GIT should replace the TST in routine practice, as well as identifies risk factors for LTBI among migrant populations.