Risk of Tuberculosis and Hepatitis B Reactivation in Patients With Crohn's Disease on Ustekinumab: A Nationwide Real-World Study

BACKGROUND

Ustekinumab (UST) was approved in China for moderate-to-severe Crohn's disease (CD) in 2020. The prevalence rates of tuberculosis and hepatitis B virus (HBV) infection are high in China, and no guideline clearly states that tuberculosis chemoprophylaxis or prophylactic anti-HBV therapy should be prescribed before UST administration. This study aimed to assess the risk of tuberculosis and HBV reactivation in CD patients with latent tuberculosis infection (LTBI) and previous HBV infection receiving UST.

METHODS

A multicenter retrospective cohort study was carried out at 68 hospitals in China to assess 721 adult CD cases administered UST between May 1, 2020, and December 31, 2021. CD and concurrent LTBI or HBV carrier were included. Hepatitis B serology, T-SPOT.TB, and tuberculin skin tests were performed at baseline. The primary outcome was tuberculosis or HBV reactivation.

RESULTS

Patients with CD-concomitant LTBI or who were HBV carriers receiving UST therapy were retrospectively enrolled from 15 hospitals in China. A total of 53 CD with LTBI patients and 17 CD with HBV carrier patients receiving UST were included. Treatment and follow-up durations were 50 ± 20 weeks and 50 ± 15 weeks in the LTBI and HBV carrier groups, respectively. A total of 25 CD patients with LTBI underwent chemoprophylaxis and 28 did not. A total of 11 HBV carriers had antiviral prophylaxis and 6 did not. No patient experienced tuberculosis or HBV reactivation or liver dysfunction during follow-up.

CONCLUSIONS

UST was safe for treatment of CD because no patient developed tuberculosis, persistent hepatitis, or acute liver failure during therapy, whether with a prophylactic regimen or not, based on our sample size and limited follow-up time.

Genetic models of latent tuberculosis in mice reveal differential influence of adaptive immunity

Studying latent Mycobacterium tuberculosis (Mtb) infection has been limited by the lack of a suitable mouse model. We discovered that transient depletion of biotin protein ligase (BPL) and thioredoxin reductase (TrxB2) results in latent infections during which Mtb cannot be detected but that relapse in a subset of mice. The immune requirements for Mtb control during latency, and the frequency of relapse, were strikingly different depending on how latency was established. TrxB2 depletion resulted in a latent infection that required adaptive immunity for control and reactivated with high frequency, whereas latent infection after BPL depletion was independent of adaptive immunity and rarely reactivated. We identified immune signatures of T cells indicative of relapse and demonstrated that BCG vaccination failed to protect mice from TB relapse. These reproducible genetic latency models allow investigation of the host immunological determinants that control the latent state and offer opportunities to evaluate therapeutic strategies in settings that mimic aspects of latency and TB relapse in humans.

Predictors of delayed sputum smear conversion among pulmonary tuberculosis patients in Kota Kinabalu, Malaysia: A retrospective cohort study

ABSTRACT

Smear-positive pulmonary tuberculosis (SPPTB) is the major contributor to the spread of tuberculosis (TB) infection, and it creates high morbidity and mortality worldwide. The objective of this study was to determine the predictors of delayed sputum smear conversion at the end of the intensive phase of TB treatment in Kota Kinabalu, Malaysia.This retrospective study was conducted utilising data of SPPTB patients treated in 5 TB treatment centres located in Kota Kinabalu, Malaysia from 2013 to 2018. Pulmonary TB (PTB) patients included in the study were those who had at least completed the intensive phase of anti-TB treatment with sputum smear results at the end of the 2nd month of treatment. The factors associated with delayed sputum smear conversion were analyzed using multiple logistic regression analysis. Predictors of sputum smear conversion at the end of intensive phase were evaluated.A total of 2641 patients from the 2013 to 2018 periods were included in this study. One hundred eighty nine (7.2%) patients were identified as having delayed sputum smear conversion at the end of the intensive phase treatment. Factors of moderate (advanced odd ratio [aOR]: 1.7) and advanced (aOR: 2.7) chest X-ray findings at diagnosis, age range of >60 (aOR: 2.1), year of enrolment 2016 (aOR: 2.8), 2017 (aOR: 3.9), and 2018 (aOR: 2.8), smokers (aOR: 1.5), no directly observed treatment short-course (DOTS) supervisor (aOR: 6.9), non-Malaysian citizens (aOR: 1.5), and suburban home locations (aOR: 1.6) were associated with delayed sputum smear conversion at the end of the intensive phase of the treatment.To improve sputum smear conversion success rate, the early detection of PTB cases has to be fine-tuned so as to reduce late or severe case presentation during diagnosis. Efforts must also be in place to encourage PTB patients to quit smoking. The percentage of patients assigned with DOTS supervisors should be increased while at the same time ensuring that vulnerable groups such as those residing in suburban localities, the elderly and migrant TB patients are provided with proper follow-up treatment and management.

High Prevalence of and Risk Factors for Latent Tuberculosis Infection among Prisoners, Tianjin, China

The high incidence of tuberculosis (TB) among prisoners calls for interventions to identify latent tuberculosis infection (LTBI) before disease onset. To identify LTBI prevalence among prisoners and factors associated with it, we conducted a cross-sectional study in Tianjin. We randomly sampled 959 HIV-negative adult prisoners by ward clusters in 5 prisons and determined LTBI by seropositivity using an interferon-γ release assay. The overall rate of LTBI was 52.0% (499/959) in the 5 facilities and ranged from 41.9% (72/172) to 60.9% (106/174). Age (adjusted odds ratio [aOR] 1.7, 95% CI 1.4–2.0 per 10 years), duration of imprisonment (aOR 1.2, 95 CI% 1.1–1.2 per year), previous incarceration (aOR 2.0, 95% CI 1.5–2.7), and facility-specific TB incidence (aOR 1.9, 95% CI 1.3–2.8) were risk factors for LTBI. These findings indicate possible TB transmission within prisons and suggest the necessity for early TB case detection, as well as prophylaxis.

Tuberculin skin test positivity among HIV-infected alcohol drinkers on antiretrovirals in south-western Uganda

BACKGROUND

Tuberculosis (TB) is the leading cause of death among people living with HIV (PLWH), and current evidence suggests that heavy alcohol users have an increased risk of developing TB disease compared to non-drinkers. Not known is whether the increased risk for TB disease among alcohol users may reflect higher rates of latent TB infection (LTBI) among this population. We assessed the latent TB infection prevalence based on tuberculin skin testing (TST) and examined association with current alcohol use among HIV-infected persons on antiretroviral therapy (ART) in south-western Uganda.

METHODS

We included PLWH at the Mbarara Regional Hospital HIV clinic, who were either current alcohol consumers (prior 3 months) or past year abstainers (2:1 enrolment ratio). Participants were recruited for a study of isoniazid preventive therapy for LTBI. TST was performed using 5 tuberculin units of purified protein derivative. The primary outcome was a positive TST reading (≥5mm induration), reflecting LTBI. We used logistic regression analyses to assess the cross-sectional association between self-reported current alcohol use and a positive TST.

RESULTS

Of the 295 of 312 (95%) who returned for TST reading, 63% were females and 63% were current alcohol drinkers. The TST positive prevalence was 27.5% (95% confidence interval [CI]: 22.6% - 32.9%). The odds of a positive TST for current alcohol users compared to abstainers was 0.76 (95% CI: 0.41, 1.41), controlling for gender, age, body mass index, history of smoking, and prior unhealthy alcohol use.

CONCLUSIONS

The prevalence of LTBI among PLWH on ART in south-western Uganda was moderate and LTBI poses a risk for future infectious TB. Although alcohol use is common, we did not detect an association between current drinking or prior unhealthy alcohol use and LTBI. Further studies to evaluate the association between LTBI and different levels of current drinking (heavy versus not) are needed.

Nutritional Adequacy and Latent Tuberculosis Infection in End-Stage Renal Disease Patients

Background: Latent tuberculosis infection (LTBI) is prevalent in end-stage renal disease (ESRD) patients. The risk of tuberculosis activation is also high. The appropriate LTBI screening and treatment is required in this population. Meanwhile, whether hemodialysis adequacy is associated with LTBI in the ESRD population is unclear. In this study, we aimed to investigate the association between hemodialysis adequacy and LTBI in ESRD patients. Methods: In the present cross-sectional study, we reviewed all outpatient-based ESRD patients in our artificial kidney room. Interferon gamma release assay (IGRA) was used for the diagnosis of LTBI. Clinical variables including nutritional adequacy (i.e., normalized protein catabolic rate, nPCR) and dialysis adequacy (i.e., Kt/V) were compared between IGRA-positive and IGRA-negative patients. Results: A total of 90 patients were enrolled, of which 20 (22.2%) had positive IGRA results using the QuantiFERON-TB method. Old fibrotic changes and nPCR (g/kg/day) were significantly different between IGRA-positive and IGRA-negative patients (both p < 0.005), while serum albumin and Kt/V were comparable (p = 0.429 and p = 0.590, respectively). Normalized PCR remained to be significant in a multivariate logistic regression analysis (adjusted hazard ratio, 0.911 (0.861–0.963); p = 0.001). The cutoff nPCR value less than 0.87 g/kg/day had an adjusted hazard ratio of 7.74 (1.77–33.74) for predicting LTBI. Patients with nPCR value less than 0.87 g/kg/day were older and had lower serum hemoglobin, albumin, calcium concentration, and Kt/V levels than those with nPCR value greater than 0.87 g/kg/day. Conclusions: Nutritional adequacy, especially when assessing nPCR value, was associated with LTBI, while dialysis adequacy was not associated with LTBI.

Latent tuberculosis infection in patients with rheumatic diseases

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.

Tuberculosis in immunosuppressed patients

Tuberculosis (TB) is one of the most significant infections in immunosuppressed patients due to its high frequency and high morbidity and mortality. TB is the leading cause of death among HIV-infected patients. The diagnosis and early treatment of latent tuberculosis infection is vital to preventing it progression to disease. Similarly, the early diagnosis of TB is key to improving the prognosis of patients and preventing its transmission. The clinical expression of TB in immunosuppressed patients is conditioned by the patient's degree of immunosuppression. It is important to keep this peculiarity in mind so as not to delay the diagnosis of suspected TB. TB treatment is basically the same in immunosuppressed patients as in the general population and any differences mainly derive from pharmacological interactions. We examined the diagnosis and treatment of TB and latent tuberculosis infection in immunosuppressed patients.

Serial QuantiFERON-TB Gold testing in patients with psoriasis treated with ustekinumab

BACKGROUND

There is increasing concern about the risk of latent tuberculosis infection (LTBI) reactivation during the use of biologics for psoriasis. Although ustekinumab had been documented with low risk of tuberculosis, the long-term follow-up of LTBI as determined by QuantiFERON-TB Gold (QFT-G) testing in patients treated with ustekinumab is limited.

OBJECTIVES

This study aims to use serial QFT-G testing as a screening method for detecting LTBI in patients with psoriasis from an intermediate tuberculosis burden country.

METHODS

This retrospective review investigated 134 psoriatic patients in whom ustekinumab was prescribed for at least one year between 2010 and 2016 in National Taiwan University Hospital. All patients underwent annular QFT-G testing during ustekinumab therapy.

RESULTS

Among the 134 enrolled patients, baseline LTBI rate was 13.4% (18/134). Indeterminate QFT-G result was noted in 5.2% (7/134) of patients and 71.4% (5/7) of them turn to be QFT-G negative during the next testing. 81.3% (109/134) of patients had a negative QFT-G at baseline and the seroconversion rate was 7.3% (8/109) in the serial QFT-G. All the patients in the conversion group were referred to a pulmonologist for evaluation and 81.5% (22/27) of them underwent chemoprophylactic therapy while on ustekinumab. No active TB infection was noted during further follow-up with or without chemoprophylaxis.

CONCLUSIONS

This study revealed that psoriatic patients receiving long-term ustekinumab therapy had a low QFT-G conversion rate (7.3%). The clinical significance of QFT-G conversion remains controversial and needs larger scale trials to investigate.

Risk factors for latent tuberculosis infection (LTBI) in health profession's students of the University of Parma

BACKGROUND AND AIM OF THE WORK

Nowadays Tuberculosis (TB) is one of the major Public Health problems for several professional categories. According to Italian law, University students are compared to workers: the main risk for them is represented by biological risk, in particular by blood-transmitted or by air-transmitted agents. As for TB, many scientific studies demonstrated that prevalence of latent tuberculosis infection (LTBI) in Medicine and Surgery students was lower than those in health workers and in general population. The main aim of this study is the evaluation both of reliability and predictive value of a specific anamnestic questionnaire for previous exposure to Mycobacterium tuberculosis, in order to identify individuals at risk for TB. The Mantoux Tuberculin Skin Test (TST) would be executed to compare results of questionnaire.

METHODS

The study included Health Profession's Degrees who were examinated during health surveillance in the period between June 2014 and March 2016. A questionnaire including 10 closed questions was presented to every student. The questionnaire was considerated positive with at least one positive answer.

RESULTS

The questionnaire was presented to 580 students, 500 of which completed TST; 466 students were Italian (93.2%). Questionnaire resulted positive in 89 students (17.8%); 15 of them presented positive TST: 14 of them was strangers (93.3%). Sensibility and specificity of questionnaire resulted 100% and 84% respectively.

CONCLUSIONS

Our data suggested that anamnestic questionnaire could be considerated an efficient mean for identifying candidates for tuberculin screening in a TB- low prevalence population.

Prevalence and predictors of latent tuberculosis infection among Italian State Policemen engaged in assistance to migrants: a national cross-sectional study

OBJECTIVES

Better knowledge about tuberculosis (TB) and latent TB infection (LTBI) epidemiology is a crucial step for the development of effective strategies towards the control and elimination of this deadliest and persistent health threat. No study has investigated LTBI epidemiology in policemen who act as an interface with cross-border migrants.

METHODS

A survey to measure the LTBI prevalence and assess the demographic, professional and clinical features potentially associated with tuberculin skin test (TST) positivity was performed in Italian State Police (ISP) employees engaged, even occasionally, in relief activities, hospitality, photographical identification, escorting and accompanying of migrants, regardless of contact with active TB cases. Variables potentially associated with TST positivity were evaluated with univariate and multivariate analysis.

RESULTS

From September to December 2014, 4225 ISP workers underwent TST screening and completed the questionnaire for data collection, according to study procedures. The TST was positive in 9.9% of individuals: no active TB cases were registered among the entire study population. Age, previous BCG vaccination and work category resulted independently associated with TST positivity.

CONCLUSIONS

This is the first study providing updated data about LTBI epidemiology among ISP employees engaged in assistance to migrants and furnish preliminary evidence of possible associations between TST positivity and different conditions that need to be deeply investigated with prospective studies.

Incidence of active mycobacterial infections in Brazilian patients with chronic inflammatory arthritis and negative evaluation for latent tuberculosis infection at baseline--a longitudinal analysis after using TNFa blockers

Several studies point to the increased risk of reactivation of latent tuberculosis infection (LTBI) in patients with chronic inflammatory arthritis (CIAs) after using tumour necrosis factor (TNF)a blockers. To study the incidence of active mycobacterial infections (aMI) in patients starting TNFa blockers, 262 patients were included in this study: 109 with rheumatoid arthritis (RA), 93 with ankylosing spondylitis (AS), 44 with juvenile idiopathic arthritis (JIA) and 16 with psoriatic arthritis (PsA). All patients had indication for anti-TNFa therapy. Epidemiologic and clinical data were evaluated and a simple X-ray and tuberculin skin test (TST) were performed. The control group included 215 healthy individuals. The follow-up was 48 months to identify cases of aMI. TST positivity was higher in patients with AS (37.6%) than in RA (12.8%), PsA (18.8%) and JIA (6.8%) (p < 0.001). In the control group, TST positivity was 32.7%. Nine (3.43%) patients were diagnosed with aMI. The overall incidence rate of aMI was 86.93/100,000 person-years [95% confidence interval (CI) 23.6-217.9] for patients and 35.79/100,000 person-years (95% CI 12.4-69.6) for control group (p < 0.001). All patients who developed aMI had no evidence of LTBI at the baseline evaluation. Patients with CIA starting TNFa blockers and no evidence of LTBI at baseline, particularly with nonreactive TST, may have higher risk of aMI.

[INCREASE IN THE NUMBER OF INFANTS WITH KOCH PHENOMENON AFTER BCG VACCINATION]

PURPOSE

To investigate the trends in the number of infants diagnosed with Koch phenomenon after BCG vaccination following the change in the timing of the vaccination.

METHOD

We extracted and analyzed data from infants aged ≤ 1 year diagnosed with latent tuberculosis infection (LTBI) or active tuberculosis, registered in the Japanese tuberculosis surveillance system, from May 2012 to the end of the year, and from May 2013 to the end of the year.

RESULT

There was no increase in active tuberculosis cases between the two periods (5 patients each). However, the number of infants with LTBI doubled (45 to 90), presumably because Koch phenomenon developed after BCG vaccination.

CONCLUSION

After changing the timing of vaccination, the number of infants experiencing Koch phenomenon appears to have increased. However, more in-depth analysis of this finding is required.

Active and latent tuberculosis in Brazilian correctional facilities: a cross-sectional study

BACKGROUND

Tuberculosis (TB) rates among prisoners are more than 20 times that of the general population in Brazil, yet there are limited data available to facilitate the development of effective interventions in this high-transmission setting. We aimed to assess risk factors for TB infection and evaluate the yield of mass screening for active disease among inmates.

METHODS

We administered a questionnaire and tuberculin skin test (TST) to a population-based sample of inmates from 12 prisons in Central-West Brazil and collected sera for HIV testing and two sputum samples for smear microscopy and culture from participants reporting a cough of any duration. Hierarchical Poisson regression models were used to evaluate factors associated with latent tuberculosis infection (LTBI).

RESULTS

We recruited 3,380 inmates, of which 2,861 (84.6%) were males from 8 prisons, and 519 (15.4%) were females from 4 prisons. Among the 1,020 (30%) subjects who reported a cough, we obtained sputum from 691 (68%) and identified 31 cases of active TB for a point prevalence of 917 (95% CI, 623-1302) per 100,000 prisoners. Evaluation of the two sputum smear samples failed to identify 74% of the TB cases, and 29% of the cases reported less than 2 weeks of symptoms. Obtaining a second culture identified an additional 7 (24%) cases. The prevalences of LTBI were 22.5% and 11.7% for male and female prisoners, respectively and duration of incarceration (in years) was associated with LTBI in male and female in the multivariable model (1.04, 95% CI, 1.01-1.07 and 1.34, 95% CI, 1.06-1.70, respectively). The prevalence of LTBI is 8.6% among newly incarcerated inmates, among whom LTBI prevalence significantly increased by 5% with each year of incarceration.

CONCLUSIONS

Although the overall LTBI prevalence among inmates in Central-West Brazil is low, tuberculosis incidence is high (>1,800/100,00), likely due to the high force of infection among a largely susceptible inmate population. Efforts to reduce transmission in prisons may require mass screening for active TB, utilizing sputum culture in case-detection protocols.

[A positive test QuantiFERON-TB Gold In-Tube in a patient treated with continuous ambulatory peritoneal dialysis]

Patients undergoing renal replacement therapy have a higher risk of developing tuberculosis (TBC) in comparison with normal renal function population. The anergy to the tuberculin skin test, the lack of characteristic clinical symptoms of TBC and typical radiographic signs, and high prevalence of extrapulmonary TBC make the diagnosis in dialysis patients difficult and often delay the treatment. In contrast to the active TBC, latent TBC infection (LTBI) is asymptomatic and is not a direct epidemiological problem. However, in patients with end-stage renal disease prepared for renal transplantation, it is an obstacle to qualifying for immunosuppressive therapy. Treatment of LTBI patients with antimycobacterial medication decreases about 90% risk of developing active TB. Therefore, the possibility of a fast and easy identification of LTBI in this group of patients is extremely important. Test QuantiFERON-TB Gold In-Tube (QFT-G) is a new, simple and rapid diagnostic tool in LTBI and active tuberculosis infection (in conjunction with previously used clinical and microbiological methods). This test has been approved and is used in many European countries and in the USA. In a 65-year old patient, treated for 5 years with continuous ambulatory peritoneal dialysis, positive QFT-G results were shownin the course of diagnosis before reporting to the transplant program. After conducting an extensive diagnosis for tuberculosis infection (epidemiological interview, clinical examination, imaging studies, cultures by MB/BacT and the conventional method, consultations with a pulmonologist), latent form of tuberculosis was diagnosed with unspecified location. Due to the positive QFT-G and the need for future immunosuppressive treatment after kidney transplantation, a three-month prophylactic treatment with Rifamazyd 450 mg per day was included. After treatment, the patient entered the waiting list for a kidney transplant. Test QFT-G, in conjunction with other conventional methods is a good and rapid diagnostic tool in the identification of LTBI.

Tuberculosis reactivation risk in dermatology

The treatment of some dermatological diseases, especially psoriasis, has been revolutionized by the advent of biologic therapies that target various immune cells or cytokines. However, biologic therapies may affect the risk of active tuberculosis (TB). We review the published safety data about TB risk reactivation for biologic agents used in dermatology. According to recent findings, psoriasis itself could represent an independent risk factor for TB; a high prevalence of TB was found in patients with psoriasis (18.0%), even after adjusting for age, work, and other characteristics. Latent TB infection was more common in patients with psoriasis (50%) than in those with inflammatory bowel disease (24.2%). Risk of TB reactivation was also influenced by the type of agent used. Several structural and functional differences among biologic drugs could account for differences in risk of granulomatous infection. Different kinetics of currently available tumor necrosis factor (TNF) antagonists, leading to different TNF bioavailability in granulomatous tissue, may explain differences in TB reactivation among patients treated with biologics. One could argue that etanercept should be the first choice of anti-TNF agent in populations at high risk of TB. Risk of TB reactivation during treatment with other biologics is not yet well defined.

Diagnosis of latent tuberculosis and prevention of reactivation in rheumatic patients receiving biologic therapy: international recommendations

OBJECTIVE

To review the official international recommendations on the management of latent tuberculosis infection (LTBI) in patients with rheumatic diseases undergoing biologic therapy.

METHODS

A systematic search of all clinical practice recommendations on the diagnosis and treatment of LTBI in rheumatic patients eligible for starting biologic drugs published between January 2002 and March 2013.

RESULTS

For the diagnosis of LTBI, based on positivity of tuberculin skin test (TST), interferon-γ release assay (IGRA) is also available. Most recommendations advise using both TST and IGRA, especially in case of Bacillus Calmette-Guérin vaccination, to screen patients before commencing biologic drugs. There is a general consensus that evaluation of the global risk of TB infection is a crucial point and that patients with LTBI must receive chemoprophylaxis prior to biologic therapy. However, recommendations on the need for rescreening for activation of LTBI or new TB infection while patients are being treated are inadequate. Nevertheless, the main concern is poor compliance with TB recommendations of rheumatologists in clinical practice, which seems to be the main cause of the occurrence of active TB in rheumatic patients receiving biologic therapy.

CONCLUSION

Notwithstanding some differences, mainly related to regional TB incidence, international recommendations strongly suggest careful screening for LTBI before starting biologic therapy. However, the critical point is implementing dissemination and awareness of the recommendations among rheumatologists to improve adherence in real life.

Safety, tolerability, and immunogenicity of the novel antituberculous vaccine RUTI: randomized, placebo-controlled phase II clinical trial in patients with latent tuberculosis infection

Objectives

To evaluate the safety, tolerability and immunogenicity of three different doses (5, 25 and 50 µg) of the novel antituberculous vaccine RUTI compared to placebo in subjects with latent tuberculosis infection.

Methods and Findings

Double-blind, randomized, placebo-controlled Phase II Clinical Trial (95 patients randomized). Three different RUTI doses and placebo were tested, randomized both in HIV-positive (n = 47) and HIV-negative subjects (n = 48), after completion of one month isoniazid (INH) pre-vaccination. Each subject received two vaccine administrations, 28 Days apart. Five patients withdrew and 90 patients completed the study. Assessment of safety showed no deaths during study. Two subjects had serious adverse events one had a retinal detachment while taking INH and was not randomized and the other had a severe local injection site abscess on each arm and was hospitalized; causality was assessed as very likely and by the end of the study the outcome had resolved. All the patients except 5 (21%) patients of the placebo group (3 HIV+ and 2 HIV−) reported at least one adverse event (AE) during the study. The most frequently occurring AEs among RUTI recipients were (% in HIV+/−): injection site reactions [erythema (91/92), induration (94/92), local nodules (46/25), local pain (66/75), sterile abscess (6/6), swelling (74/83), ulcer (20/11), headache (17/22) and nasopharyngitis (20/5)]. These events were mostly mild and well tolerated. Overall, a polyantigenic response was observed, which differed by HIV− status. The best polyantigenic response was obtained when administrating 25 µg RUTI, especially in HIV-positive subjects which was not increased after the second inoculation.

Conclusion

This Phase II clinical trial demonstrates reasonable tolerability of RUTI. The immunogenicity profile of RUTI vaccine in LTBI subjects, even being variable among groups, allows us considering one single injection of one of the highest doses in future trials, preceded by an extended safety clinical phase.

Trial Registration

ClinicalTrials.gov NCT01136161

Frequent detection of latent tuberculosis infection among aged underground hard coal miners in the absence of recent tuberculosis exposure

Background

Miners are at particular risk for tuberculosis (TB) infection due to exposure to silica dust and silicosis. The objectives of the present observational cohort study were to determine the prevalence of latent TB infection (LTBI) among aged German underground hard coal miners with silicosis or chronic obstructive pulmonary disease (COPD) using two commercial interferon-gamma release assays (IGRAs) and to compare their performance with respect to predictors of test positivity.

Methods

Between October 2008 and June 2010, miners were consecutively recruited when routinely attending pneumoconiosis clinics for an expert opinion. Both IGRAs, the QuantiFERON®-TB Gold In-Tube (QFT) and the T-SPOT®.TB (T-SPOT), were performed at baseline. A standardized clinical interview was conducted at baseline and at follow-up. The cohort was prospectively followed regarding the development of active TB for at least two years after inclusion of the last study subject. Independent predictors of IGRA positivity were calculated using logistic regression.

Results

Among 118 subjects (mean age 75 years), none reported recent exposure to TB. Overall, the QFT and the T-SPOT yielded similarly high rates of positive results (QFT: 46.6%; 95% confidence interval 37.6–55.6%; T-SPOT: 61.0%; 95% confidence interval 52.2–69.8%). Positive results were independently predicted by age ≥80 years and foreign country of birth for both IGRAs. In addition, radiological evidence of prior healed TB increased the chance of a positive QFT result fivefold. While 28 subjects were lost to follow-up, no cases of active TB occurred among 90 subjects during an average follow-up of >2 years.

Conclusions

Considering the high prevalence of LTBI, the absence of recent TB exposure, and the currently low TB incidence in Germany, our study provides evidence for the persistence of specific interferon-gamma responses even decades after putative exposure. However, the clinical value of current IGRAs among our study population, although probably limited, remains uncertain.

A prospective longitudinal study evaluating a T-cell-based assay for latent tuberculosis infection in health-care workers in a general hospital in Beijing

BACKGROUND

The health-care workers (HCWs) are at high risk of acquiring infection with Mycobacterium tuberculosis. The objectives of this study were to compare the performance of the T-SPOT.TB and tuberculin skin test (TST) for latent tuberculosis infection (LTBI), evaluate diagnostic concordance and risk factors for LTBI, and observe the progression to active tuberculosis (TB) disease among HCWs in a general hospital in Beijing.

METHODS

The prospective cohort study enrolled HCWs in a tertiary general hospital in Beijing, China, to evaluate LTBI with T-SPOT.TB and TST. The subjects were evaluated every 12 months during the 60-month follow-up.

RESULTS

Of 101 participating HCWs, 96 and 101 had valid TST and T-SPOT.TB results, respectively. Twenty-nine (28.7%, 95% confidence interval (CI), 19.9% - 37.5%) were defined as positive by T-SPOT.TB and 53 (55.2%, 95%CI, 45.2% - 64.9%) were defined as positive by TST (using a ≥ 10 mm cutoff). An agreement between the two tests was poor (57.3%, κ = 0.18, 95%CI, 0.01% - 0.52%). In multivariate analysis, direct exposure to sputum smear-positive TB patients was a significant risk factor for a positive T-SPOT.TB (OR 5.76; 95%CI 1.38 - 24.00). Pooled frequency of antigen-specific IFN-γ secreting T-cells for subjects who reported direct contact with sputum smear-positive TB patients was significantly higher than that for participants without direct contact (P = 0.045). One of 20 participants with positive result of T-SPOT.TB and TST developed active TB at 24-month follow-up.

CONCLUSION

T-SPOT.TB is a more accurate, targeted method of diagnosing LTBI than TST.

Tuberculosis in solid organ transplant patients

Tuberculosis is an opportunistic infection with high morbidity and mortality in solid organ transplant patients. The reasons for this high morbidity and mortality lie mostly in diagnostic difficulties, which cause delays in starting treatment, and associated pharmaceutical toxicity. There are still major issues and difficulties in managing tuberculosis in solid organ transplant patients. These include problems due to interactions between antituberculosis and immunosuppressant drugs, the high risk of toxicity of antituberculosis drugs (particularly in liver transplant patients) and the absence of clear indications for the treatment of latent tuberculous infection. This article updates current understanding of tuberculosis in solid organ transplant patients.

Latent M. tuberculosis infection--pathogenesis, diagnosis, treatment and prevention strategies

One third of the earths population is infected with Mycobacterium tuberculosis (Mtb), but only 5-10% of the infected individuals develop active tuberculosis (TB) over their lifetime. The remaining 90-95% stay healthy and are called latently infected individuals. They are the biggest reservoir of the tubercle bacilli and identifying the cases of latent TB is a part of the global plan of TB control. From the clinical point of view detection of latent TB infections (LTBI) in individuals with the highest active TB risk including cases of HIV infection, autoimmune inflammatory diseases or cancer, is a priority. This review summarizes the recent findings in the pathogenesis of latent TB, its diagnosis, treatment and prevention.