Search Results (33)

Background/Objectives: Patients with immune-mediated inflammatory diseases (IMIDs) treated with disease-modifying antirheumatic drugs (DMARDs) are at increased risk of latent tuberculosis infection (LTBI) reactivation, influenced by DMARD type. This study aimed to determine LTBI prevalence using interferon-gamma release assays (IGRAs) and identify associated risk factors in IMID patients in a middle-high TB burden setting in Mexico. Methods: A cross-sectional study was conducted from July 2024 to April 2025 at an IMID clinic. Patients aged ≥18 years, either receiving DMARDs or prior to initiating treatment, were included. LTBI was diagnosed using the QuantiFERON-TB Gold Plus assay. Bivariate analysis was performed using the chi-square test, and multivariate analysis was conducted. Results: LTBI prevalence was 34.2% (95% CI 29.1–39.7%) according to QFT-Plus and 35.6% (95% CI 29.7–42.0%) according to TSTs (n = 230). Prior TB exposure was the strongest risk factor (aOR 4.20, 95% CI 1.74–10.12, p = 0.001), while rheumatoid arthritis was associated with a lower LTBI likelihood (aOR 0.31, 95% CI 0.16–0.59, p < 0.001). Conclusions: A high prevalence of LTBI was observed in patients with IMIDs treated with DMARDs. Prior tuberculosis exposure was strongly associated with LTBI. These findings highlight the importance of LTBI screening in this population to prevent reactivation. Full article

Background/Objectives: Healthcare workers (HCWs) are globally recognized as a high-risk group for tuberculosis (TB) infection. However, limited data exist on the prevalence of latent TB infection (LTBI) and associated occupational risk factors in the Mexican context. Identifying the burden of LTBI is essential for effective prevention. This study aimed to estimate the prevalence of LTBI among HCWs in a tertiary care hospital in Mexico and to explore associated risk factors. Methods: An analytical cross-sectional study was conducted among 300 HCWs (including physicians, nurses, and stretcher-bearers) at a tertiary-level hospital in Mexico. Sociodemographic and occupational data were collected through a structured questionnaire. LTBI screening was performed using the tuberculin skin test (TST), with positive results confirmed via the QuantiFERON-TB Gold assay. Associations between relevant variables and LTBI were assessed using logistic regression models, adjusted for potential confounders. Results: The prevalence of LTBI was 16.7%. After adjusting for confounders, male HCWs had significantly higher odds of LTBI compared to females (adjusted odds ratio [aOR] = 2.02; 95% confidence interval [CI]: 1.06–3.80). Although elevated odds of LTBI were also observed among physicians, stretcher-bearers, and those with direct contact with TB patients, these associations were not statistically significant. Conclusion: LTBI represents a relevant occupational health issue among HCWs, with nearly one in six workers affected. Early detection and prevention of TB in healthcare settings are critical to protecting individual workers and public health. These findings highlight the need to strengthen occupational TB surveillance and prevention strategies in similar healthcare environments. Full article

Healthcare workers (HCWs) face an increased risk of tuberculosis (TB) due to occupational exposure. This study aimed to estimate the point prevalence of TB infection (TBI) from the initial test performed, while the reversion and conversion were done by subsequent testing at one year among HCWs in Puducherry, India. A prospective cohort study was conducted among a sample of proportionately chosen HCWs based on their occupational strata of a tertiary hospital in 2022. TBI was assessed using IGRA (4th generation QuantiFeron—TB gold plus kits) after TB symptom screening. The IGRA test was repeated at the end of one year. Reversion was defined as a positive IGRA test at the baseline and had values < 0.2 IU/L in TB1 or TB2 tubes during follow-up. Conversion was defined as a negative IGRA result at the baseline and had values of >0.7 IU/L in TB1 or TB2 tubes during follow-up. Of the 400 HCWs included, the mean (SD) age was 37 (7) years. Median (IQR) work experience was 15.7 (10–21) years. TBI was seen in 150 HCWs (37.7%, 95% CI: 33.0–42.7), and one had active TB. A total of 128/150 HCWs with TBI at baseline were followed up, and 15 had TBI reversion (11.7 per 100 person-years; 95% CI: 6.7–18.5). Thirteen HCWs (5.6 per 100 person-years; 95% CI: 3.3–9.8) had TBI conversion. Full article

Background/Objectives: Classic Hodgkin lymphoma (cHL) is a predominantly curable B-cell malignancy. However, primary refractory and relapsed (R/R) cHL remain therapeutic challenges, especially in regions with high tuberculosis (TB) prevalence, where clinical and radiologic features overlap and can obscure the correct diagnosis. This article, presenting a case of R/R cHL mimicking disseminated TB, reviews the evolving paradigm in R/R cHL management. Methods: A 30-year-old Middle Eastern male with advanced nodular sclerosis cHL initially achieved a complete remission (CR) with escalated BEACOPP chemotherapy. Shortly afterward, he developed respiratory symptoms and diffuse miliary pulmonary nodules, highly suggestive of disseminated TB. Despite extensive negative TB workup, including QuantiFERON-TB Gold testing, sputum acid-fast bacilli (AFB) staining, and PCR, his imaging raised concern for recurrent cHL. Due to the small size and diffuse distribution of nodules, biopsy was unfeasible, prompting empiric salvage therapy with DEHAP-Carbo, brentuximab vedotin (BV), and nivolumab. Results: The rapid and robust metabolic response on PET/CT supported lymphoma relapse rather than TB. Following four cycles of this combined regimen, he proceeded to autologous stem cell transplantation and achieved a second CR. Conclusions: This case highlights the diagnostic difficulties in differentiating cHL relapse from TB in endemic regions, emphasizes the critical role of PET/CT in guiding therapy when histopathological confirmation is impractical, and illustrates the impact of novel immunotherapies in improving outcomes. By underscoring the importance of early diagnostic suspicion and multimodal assessment, this article also reviews the evolving paradigm in R/R cHL management, where personalized approaches and targeted agents increasingly complement or replace traditional chemotherapy regimens. Full article

Latent tuberculosis infection (LTBI) remains a significant global health concern, particularly in regions with high tuberculosis (TB) prevalence, such as South Africa. This pilot study aimed to evaluate the prevalence of LTBI and assess patient knowledge about the condition in a primary healthcare clinic in rural Eastern Cape, South Africa. A cross-sectional design was used, and convenience sampling recruited outpatients aged 18 years and older with no prior history of TB. Blood samples were analyzed using the QuantiFERON-TB Gold assay to determine LTBI status, and a survey assessed patient knowledge of LTBI. Strong positive correlations were observed between what patients understand by the term LTBI and how LTBI differs from TB (0.70), what patients understand by the term LTBI and the risk factors for developing LTBI (0.70), how LTBI differs from TB and the risk factors for developing LTBI (0.78), and how LTBI differs from TB and the recommended treatments for LTBI (0.79), indicating overlap in understanding. In contrast, there were negative correlations between if patients had ever heard of latent LTBI before and their understanding of the term LTBI (−0.25), the risk factors for developing LTBI (−0.22), LTBI progressing to active TB (−0.27), and the recommended treatments for LTBI (−0.27). This divergence points to different dimensions of patient knowledge and awareness. Age, gender, occupation, comorbidities, and HIV status showed varying LTBI positivity trends. Among younger patients aged 20–29, 15.4% tested positive, while the 30–39 group showed a nearly equal split between positive (48.1%) and negative cases. A higher positivity rate was seen in females (39.1%) compared to males (31.6%). Unemployed individuals had higher positivity rates, suggesting socioeconomic factors’ influence. Comorbidities, especially hypertension, diabetes, and asthma, correlated with higher LTBI positivity among females, but this was less evident in males. HIV-positive patients had a higher LTBI-negative rate compared to HIV-negative patients. A logistic regression model (accuracy 70%) identified demographic and health factors predicting LTBI outcomes, with comorbidities, particularly hypertension and diabetes, significantly increasing the likelihood of LTBI positivity. These findings suggest that demographic and health factors, including age, gender, occupation, comorbidities, and HIV status, may predict LTBI positivity. Full article

Human T-cell leukemia virus type 1 (HTLV-1) is associated with an increased risk of tuberculosis (TB). This study aimed to evaluate the performance of the QuantiFERON-TB Gold (QFT) test for the diagnosis of Mycobacterium tuberculosis (MTB) infection in HTLV-1-infected individuals. HTLV-1-infected participants were divided into four groups: HTLV-1-infected individuals with a history of tuberculosis (HTLV/TB), individuals with positive HTLV and tuberculin skin tests (HTLV/TST+) or negative TST (HTLV/TST−), and HTLV-1-negative individuals with positive TST results (HN/TST+). We compared the diagnostic performance of the QFT assay with that of the TST as a reference and evaluated test sensitivity, specificity, accuracy, likelihood ratio, and diagnostic odds ratio. The results showed a higher frequency of positive TST results and induration diameter ≥10 mm in HTLV-1-infected individuals than in the controls. The QFT test was more frequently positive in the HTLV/TB group than in the other groups, while a combined analysis of HTLV/TB and HTLV/TST+ indicated a QFT sensitivity of 57.5%. No significant differences were found in the other diagnostic performance measures, as QFT test results were in agreement with TST results, particularly in TST-negative individuals. Given the low sensitivity of QFT for LTBI in individuals infected with HTLV-1, the TST may be preferable in regions where both infections are endemic. Full article

Actinomycosis, an uncommon granulomatous infection caused by the Actinomyces species, rarely targets as primary involvement the limb and is often linked to traumatic incidents. In this report, we present the case of a 44-year-old female who developed multiple small nodules on her left foot over approximately 12 months. Some nodules exhibited firmness and a violet hue, while others discharged a yellowish fluid. The patient had no significant comorbidities. Despite thorough blood paraclinical assessments, including complete blood count, serological HIV testing, and QuantiFERON-TB Gold testing, no abnormalities were detected. Bacteriological examinations and cultures of the discharge yielded negative results. Dermatoscopic examination revealed ovoid yellowish structures, with confocal microscopy highlighting granulomas. A subsequent skin biopsy confirmed characteristic changes indicative of actinomycosis. Although systemic antibiotic therapy with penicillin derivatives was initially considered, the patient’s documented allergic history to this medication class, verified through allergological testing, prompted the initiation of doxycycline treatment. Notably, significant improvement was observed at the 3-month follow-up. This case underscores the importance of reporting rare instances of actinomycosis due to its diagnostic complexity and management challenges. Full article

Background: The coexistence of HIV infection and latent tuberculosis infection (LTBI) presents a significant public health concern due to the increased risk of tuberculosis (TB) reactivation and progression to active disease. The multicenter observational cohort study, TUBHIVIT, conducted in Italy from 2017 to 2023, aimed to assess the prevalence of LTBI among people living with HIV (PLHIV) and their outcomes following LTBI screening and therapy initiation. Methods: We performed a prospective study in five referral centers for HIV care in Italy. PLHIV who consented Tto participate underwent QuantiFERON-TB Gold Plus and clinical, microbiological, and radiological assessments to exclude subclinical tuberculosis, as opportune. PLHIV diagnosed with LTBI who started chemoprophylaxis were followed until the end of therapy. Results: A total of 1105 PLHIV were screened for LTBI using the QuantiFERON-TB Gold Plus test, revealing a prevalence of 3.4% of positive results (38/1105). Non-Italy-born individuals exhibited a significantly higher likelihood of testing positive. Thirty-one were diagnosed with LTBI, 1 showed active subclinical TB, and 6 were lost to follow-up before discriminating between latent and active TB. Among the PLHIV diagnosed with LTBI, 83.9% (26/31) started chemoprophylaxis. Most individuals received 6–9 months of isoniazid-based therapy. Of the 26 PLHIV commencing chemoprophylaxis, 18 (69.2%) completed the therapy, while 3 discontinued it and 5 were still on treatment at the time of the analysis. Adverse events were observed in two cases, while in one case the patient refused to continue the treatment. Full article

The National TB Elimination Programme (NTEP) of India is implementing tuberculosis preventive treatment (TPT) for all household contacts (HHCs) of pulmonary tuberculosis patients (index patients) aged <5 years and those HHCs aged >5 years with TB infection (TBI). We conducted an explanatory mixed-methods study among index patients registered in the Kolar district, Karnataka during April-December 2022, to assess the TPT cascade and explore the early implementation challenges for TPT provision. Of the 301 index patients, contact tracing home visits were made in 247 (82.1%) instances; a major challenge was index patients’ resistance to home visits fearing stigma, especially among those receiving care from the private sector. Of the 838 HHCs, 765 (91.3%) were screened for TB; the challenges included a lack of clarity on HHC definition and the non-availability of HHCs during house visits. Only 400 (57.8%) of the 692 eligible HHCs underwent an IGRA test for TBI; the challenges included a shortage of IGRA testing logistics and the perceived low risk among HHCs. As HHCs were unaware of their IGRA results, a number of HHCs actually eligible for TPT could not be determined. Among the 83 HHCs advised of the TPT, 81 (98%) initiated treatment, of whom 63 (77%) completed treatment. Though TPT initiation and completion rates are appreciable, the NTEP needs to urgently address the challenges in contact identification and IGRA testing. Full article

Tuberculosis (TB) is one of the leading causes of death by an infectious disease. It remains a major health burden worldwide, in part due to misdiagnosis. Therefore, improved diagnostic tests allowing the faster and more reliable diagnosis of patients with active TB are urgently needed. This prospective study examined the performance of the new molecular whole-blood test T-Track^® TB, which relies on the combined evaluation of IFNG and CXCL10 mRNA levels, and compared it to that of the QuantiFERON^®-TB Gold Plus (QFT-Plus) enzyme-linked immunosorbent assay (ELISA). Diagnostic accuracy and agreement analyses were conducted on the whole blood of 181 active TB patients and 163 non-TB controls. T-Track^® TB presented sensitivity of 94.9% and specificity of 93.8% for the detection of active TB vs. non-TB controls. In comparison, the QFT-Plus ELISA showed sensitivity of 84.3%. The sensitivity of T-Track^® TB was significantly higher (p < 0.001) than that of QFT-Plus. The overall agreement of T-Track^® TB with QFT-Plus to diagnose active TB was 87.9%. Out of 21 samples with discordant results, 19 were correctly classified by T-Track^® TB while misclassified by QFT-Plus (T-Track^® TB-positive/QFT-Plus-negative), and two samples were misclassified by T-Track^® TB while correctly classified by QFT-Plus (T-Track^® TB-negative/QFT-Plus-positive). Our results demonstrate the excellent performance of the T-Track^® TB molecular assay and its suitability to accurately detect TB infection and discriminate active TB patients from non-infected controls. Full article

The present study aimed to clinically evaluate the effect of T-cell dysfunction in hemodialysis (HD) patients with latent tuberculosis (TB) infection (LTBI) who were false-negatives in the QuantiFERON-TB Gold In-Tube (QFT-GIT) test. Whole blood samples from a total of 20 active TB patients, 83 HD patients, and 52 healthy individuals were collected, and the QFT-GIT test was used for measuring Mycobacterium tuberculosis (MTB)-specific interferon gamma (IFN-γ) level. The positive rate of the IFN-γ release assays (IGRAs) in HD patients was lower than the negative rate. The mean value of MTB-specific IFN-γ level, which determines the positive rate of the IGRA test, was highest in active TB, followed by HD patients and healthy individuals. Among HD patients, phytohemagglutinin A (PHA)-stimulated IFN-γ levels of approximately 40% were 10.00 IU/mL or less. However, there was no low level of PHA-stimulated IFN-γ in the healthy individuals. This reveals that T-cell function in HD patients was reduced compared to healthy individuals, which leads to the possibility that QFT-GIT results in HD patients are false-negative. The clinical manifestations of TB in patients on HD are quite non-specific, making timely diagnosis difficult and delaying the initiation of curative treatment, delay being a major determinant of outcome. Full article

Objectives The value of QuantiFERON-TB Gold In-Tube (QFT-GIT) in the diagnosis of TB varies by population, comorbidities, and other factors. In this study, we aimed to investigate factors that influence false-negative results of QFT-GIT test in the diagnosis of TB as well as the impact of different cutoffs on the diagnostic value. Methods A total of 3562 patients who underwent QFT-GIT tests at Shanghai Pulmonary Hospital were enrolled retrospectively between May 2016 and May 2017. False-negative and false-positive results were analyzed using different clinical stratifications. The optimal cutoff values were established under different clinical conditions. Results Positive QFT-GIT results greatly shortened the time taken to diagnose smear-negative TB. The factors of age, smear and culture results, site of TB, comorbidity with tumors, white blood cell count, neutrophil count, and CD4/CD8 ratio were significantly correlated with false-negative QFT-GIT results (p < 0.05). Personalized cutoff values were established according to different influencing factors. The results showed high consistency between the smear-negative and total populations. Conclusion QFT-GIT can facilitate the early diagnosis of smear-negative TB. The diagnostic performance of the QFT-GIT test in the diagnosis of active TB was shown to be affected by many clinical factors. Personalized cutoff values may have superior value in the identification of active tuberculosis under different conditions. Full article

Mycobacterium bovis (M. bovis) infection in wildlife, including lions (Panthera leo), has implications for individual and population health. Tools for the detection of infected lions are needed for diagnosis and disease surveillance. This study aimed to evaluate the Mabtech Cat interferon gamma (IFN-γ) ELISA^Basic kit for detection of native lion IFN-γ in whole blood samples stimulated using the QuantiFERON^® TB Gold Plus (QFT) platform as a potential diagnostic assay. The ELISA was able to detect lion IFN-γ in mitogen-stimulated samples, with good parallelism, linearity, and a working range of 15.6–500 pg/mL. Minimal matrix interference was observed in the recovery of domestic cat rIFN-γ in lion plasma. Both intra- and inter-assay reproducibility had a coefficient of variation less than 10%, while the limit of detection and quantification were 7.8 pg/mL and 31.2 pg/mL, respectively. The diagnostic performance of the QFT Mabtech Cat interferon gamma release assay (IGRA) was determined using mycobacterial antigen-stimulated samples from M. bovis culture-confirmed infected (n = 8) and uninfected (n = 4) lions. A lion-specific cut-off value (33 pg/mL) was calculated, and the sensitivity and specificity were determined to be 87.5% and 100%, respectively. Although additional samples should be tested, the QFT Mabtech Cat IGRA could identify M. bovis-infected African lions. Full article

It is important to identify cases of latent tuberculosis infection (LTBI) who are at risk for tuberculosis (TB) reactivation. We aimed to evaluate the performance of interferon (IFN)-gamma-inducible protein 10 (IP-10) as a marker to detect LTBI in patients with inflammatory rheumatic diseases (IRD). This study comprised 76 consecutive subjects with IRD. Patients with a history of TB or having active TB were excluded. In all patients, IP-10 level was measured and tuberculin skin test (TST) and QuantiFERON-TB Gold In-Tube test (QFT-GIT) were performed. Seventy patients with complete test results were analyzed. Twenty-one (30%) QFT-GIT-positive patients were defined as having LTBI. IP-10 yielded 2197 pg/mL cut-off point. At this cut-off point, IP-10 showed 89% specificity with a sensitivity of 91% (AUC: 0.950, 95% CI 0.906–0.994). TST, QFT-GIT, and IP-10 were positive in 77.1%, 30%, and 44.3% of the patients, respectively. Concordance among the results of TST, QFT-GIT, and IP-10 tests was evaluated. Agreement was poor between IP-10 and TST (58.6%, κ = 0.19), whereas it was good between QFT-GIT and IP-10 (84.3%, κ = 0.65). The results of the present study demonstrated that sensitivity and specificity of released IP-10 were as high as those of QFT-GIT in indicating LTBI in IRD patient group. Full article

Background/Aims: Controversy exists regarding 3- or 4 drug antituberculosis therapy (conventional ATT) in uveitis patients having latent tuberculosis (LTB), especially while initiating therapy with corticosteroids and/or other immunosuppressants. Methods: We performed a monocentral retrospective analysis of posterior uveitis patients with latent TB. Latent TB was diagnosed, in case of a positive QuantiFERON^®-TB-Gold test and normal chest imaging, after ruling out other causes of infectious and noninfectious uveitis. Patients with active TB were excluded. From 2016 to 2020 we included 17 patients. Ophthalmological evaluation consisted of Best corrected visual acuity (BCVA), slit lamp examination, fundoscopy, OCT, and fluorescein- and indocyaningreen- angiography before and at months 3, 6, 12, 24, and the last follow-up after treatment. Results: Initially, all patients had active posterior uveitis with occlusive (n = 5 patients) and nonocclusive retinal vasculitis (n = 12 patients). Mean follow up was 28 ± 15 months. Therapy was started with systemic corticosteroids (mean prednisolone equivalent 71.3 mg/d) and already after 3 months it could be tapered to a mean maintenance dosage of 8.63 mg/d. Additional immunosuppressive treatment with cs- or bDMARDs was initiated in 14 patients (82%) due to recurrences of uveitis while tapering the corticosteroids <10 mg per/day or because of severe inflammation at the initial visit. While being on immunosuppression, best corrected visual acuity increased from 0.56 logMAR to 0.32 logMAR during follow-up and only three patients had one uveitis relapse, which was followed by switch of immunosuppressive treatment. As recommended, TB prophylaxis with 300 mg/d isoniazid was administered in 11 patients for at least 9 months while being on TNF-alpha-blocking agents. No patient developed active tuberculosis during immunosuppressive therapy. Conclusion: Mainly conventional ATT is strongly recommended—as monotherapy or in combination with immunosuppressives—for effective treatment in patients with uveitis due to latent TB. Although in our patient group no conventional ATT was initiated, immunosuppression alone occurred as an efficient treatment. Nevertheless, due to possible activation of TB, isoniazid prophylaxis is mandatory in latent TB patients while being on TNF-alpha blocking agents. Full article