QuantiFERON TB Research Articles

Tuberculosis and other causes of uveitis in Indonesia.

PurposeThe purpose of this study is to assess the causes of uveitis in Indonesia and determine the importance of tuberculosis (TB) as a cause of uveitis.Patients and methodsProspective cohort study examining 146 consecutive new human immunodeficiency virus-negative patients with active uveitis between June 2014 and May 2015. We assessed the anatomic locations and specific causes of uveitis, as well as associations with infectious and non-infectious systemic diseases. We determined the prevalence of positive QuantiFERON Tb Gold test (QFT) results in Indonesian patients with uveitis and calculated the number of patients with active systemic TB.ResultsPosterior and panuveitis were the most common anatomic entities (38% each). Infections represented the most frequent cause of uveitis (33%); the most prevalent were toxoplasmosis (19%) and active systemic TB (8%). The majority of patients were QFT positive (61%). A specific diagnosis could not be established in 45% of the patients. At first presentation to the ophthalmologist, the majority of patients (66%) had a visual acuity of less than finger counting at 3 m and already exhibited various complications of uveitis. When classifying the QFT-positive patients with unexplained uveitis into a TB-related group, the percentage of 'TB-associated' uveitis cases increased from 8-48%. Highly elevated QFT levels were observed in patients with uveitis of unknown cause and no signs of active systemic TB.ConclusionsIn Indonesia, infectious uveitis was the most common type of uveitis and the leading causes consisted of toxoplasmosis and TB. The association observed between highly elevated QFT results and uveitis of otherwise unexplained origins indicates that a link exists between the latent TB infection and the development of uveitis.

Choroidal neovascular membranes secondary to intraocular tuberculosis misdiagnosed as neovascular age-related macular degeneration.

Intraocular tuberculosis (IOTB) can be complicated by choroidal neovascularization (CNV). However, when the CNV development is not accompanied by clear signs of inflammation, the etiology can be missed, especially in countries nonendemic for tuberculosis. We describe the clinical and imaging features of CNVs presenting as the first sign of IOTB initially misdiagnosed as exudative age-related macular degeneration (AMD). A retrospective review of clinical and imaging data of patients initially misdiagnosed with neovascular AMD later diagnosed with inflammatory CNV secondary to IOTB at tertiary referral centers was conducted. Features of fundus photography, fluorescein angiography, indocyanine green angiography, and enhanced depth imaging optical coherence tomography were analyzed. Distinguishing features between neovascular AMD and IOTB-associated CNV were evaluated. Five patients over 55 years of age, erroneously diagnosed with exudative AMD, were included in the study. Multimodal imaging analysis allowed identification of peculiar choroidal alterations such as choroidal granulomas or choroiditis suggestive for posterior uveitis. Systemic workup for granulomatous uveitis including immunologic investigations such as tuberculin skin test or QuantiFERON TB Gold® and radiologic investigations revealed tubercular etiology in all the cases, allowing correct diagnosis and management of the uveitis and related CNV. Choroidal neovascularization represents a rare and unusual presenting sign of IOTB that can be misleading especially when it occurs in the elderly living in countries with low prevalence of the disease. Multimodal imaging can be helpful and should be employed, especially in atypical cases of CNV, in order to avoid misdiagnosis and/or diagnostic delays.

Orofacial Granulomatosis: Food for Thought!

Orofacial granulomatosis is a relatively recent term coined by Weinsfeld et al in 1995 to describe the presence of oral granulomatous lesions without intestinal involvement. It could manifest either as a triad involving facial nerve, lip swelling, fissured or furrowed tongue referred to as Melkerson Rosenthal Syndrome (MRS) or its monosymptomatic or oligosymptomatic forms referred to as Granulomatous Cheilitis (GC). 31-year-old Caucasian male with complaints of painful swelling of the lips with recurrent oral ulcers and difficulty eating for 3 years. Exam was significant for painful, right-sided lip, tongue, and facial swelling with an 8 mm shallow intraoral ulcer. ESR, quantiferon tb, celiac panel, ACE levels, heavy metal and food allergen test were negative ASCA antibodies were positive but EGD, CT- enterography and colonoscopy which showed no evidence of intestinal involvement. Biopsy of oral lesion revealed multiple non-caseating granulomas with multinucleated giant cells consistent with granulomatous cheilitis. Patient did not respond to dapsone, oral and intralesional corticosteroids, so infliximab 10 mg/kg induction dose followed by 10 mg/kg every 4 weeks was started with resolution of the swelling and ulcers. Granulomatous cheilitis is a persistent, relapsing remitting, idiopathic, non-tender swelling of one or both lips. The etiology is unknown, however relationship to crohn's disease, sarcoidosis and various infectious and allergens has been reported but none has been validated. There is a distinct clinical entity backed by genetic studies which have suggested that OFG may have a different HLA profile than Crohns disease. Topical, systemic and intralesional corticosteroids have been used with variable outcomes. Infliximab was first reported for the treatment of orofacial Crohns in 2001.There have been 5 other case reports that have described the use of Infliximab or adalimumab for the treatment of OFG. The dose of Infliximab used in most of those studies was 3-5 mg/kg and the duration of treatment varied from 3 weeks to 21 month. Our patient had resolution of lesions with 10 mg/kg of infliximab and has had sustained response for the past 8 months. In conclusion, we believe that OFG is a distinict entity seperate from Crohns disease and high dose Infliximab should be considered an alternative treatment options in patients who do not respond to other treatment regimens.

Scleritis as a Presenting Sign of Stage IV Lung Adenocarcinoma

SESSION TITLE: Non-Small Cell Lung Cancer SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: Scleritis is attributed to an underlying systemic disease in up to 50% of cases, with infections recognized as the cause in another 7% of cases. Non infectious scleritis occurs in the setting of rheumatologic disorders, surgery, and rarely malignancies. While infectious and noninfectious scleritis are often indistinguishable, the treatments are anything but uniform. Our case emphasizes the importance of early clinical suspicion for malignancy as a cause of treatment resistant scleritis. CASE PRESENTATION: A 56 year old West African male with HIV on antiretroviral therapy (CD4 694) presented from a community ophthalmology clinic with progressive vision loss of the left eye (OS), increased lacrimation, and pain for one month despite topical steroid therapy. While he endorsed a 20lb weight loss he denied any headaches, trauma, fevers, chills, night sweats, cough, hemoptysis, rashes or similar prior episodes. Exam revealed decreased visual acuity limited to hand motion and 3+ injection OS. Right eye exam was benign. He was diagnosed with anterior and posterior scleritis, a serous retinal detachment and a sub-retinal mass OS. Workup was notable for ESR 55mm/hr, and CRP 93mg/L but normal ACE, ANCA, ANA, RPR, Lyme Ab, Quantiferon Tb gold, RF, and HLA-B27. Chest X-ray revealed a right upper lobe (RUL) mass with a small right effusion. CT chest showed a 7cm RUL mass, adenopathy, and a right chest wall mass. Further imaging showed metastatic disease involving the adrenals, kidney, diaphragm, and spine. MRI of the brain and orbits revealed multiple brain metastases and a retinal detachment OS. Biopsy confirmed a diagnosis of metastatic lung adenocarcinoma. DISCUSSION: While the eye is a rare site of malignancy in adults, metastatic spread from primary breast, lung, or gastrointestinal cancers constitute the majority of cases. In fact, ocular metastases most often occur in patients with a prior known malignancy diagnosis. Lung cancer, in contrast, often metastasizes early to the uveal tract, with ocular metastasis representing the first sign of disease. While serous retinal detachments due to choroidal metastasis are well documented, malignancy-associated scleritis is rare and reported in only a few case reports. Our case demonstrates two potential vision compromising complications of choroidal metastasis as the presenting signs of underlying lung cancer, specifically serous retinal detachments and scleritis. CONCLUSIONS: Scleritis as an initial presentation of metastatic cancer may be rare, however, it has been described in the literature. As in this case, there are times when scleritis is the first and only sign of deeper underlying pathology. It is thus prudent to investigate each case of scleritis in depth. If routine treatments do not promptly lead to resolution of symptoms, then the differential should expand to include systemic diseases such as malignancies. Reference #1: Cohen VML. Eye. 2013;27(2):137-141 Reference #2: Diaz JD. et al. Surv Ophthalmol. 2016;61(6):702-717 DISCLOSURE: The following authors have nothing to disclose: Matthew Wieder, Ana Velazquez, Margarita Chernovolenko, Veevek Anand Agrawal No Product/Research Disclosure Information

GAMMA İNTERFERON SALINIM TESTİ İLE LATENT TÜBERKÜLOZ İNFEKSİYONUNUN ARAŞTIRILMASI

Objective: The initial infection of tuberculosis is usually confidential and limited by body defense mechanisms. If there is weakening of the body resistance, this infection may become active. Latent infection can not be recognized as radiological and bacteriologically. Early detection of infection is necessary before immunosuppressive therapies are used in many diseases today. It is also important to demonstrated to transmission of tuberculosis from family members and presence of infections in small children. Methods: A total of 76 people were included in the study between 20.02.2016-15.03.2017 with patients with tuberculosis suspicion at Duzce University Faculty of Medicine Hospital's intensive care unit and outpatient clinics, health personel and tuberculosis dispensary personel. Gamma interferon release assay "Quantiferon-Tb Gold ELISA test (QIAGEN, Germany)" was used to demonstrate latent infection. Results: A total of 19 (25%) subjects had a positive test. Of the 19 patients who were positive, 8 (42%) had a pulmonary tuberculosis pre-diagnosis, 4 (21%) of them had an extrapulmonary tuberculosis pre-diagnosis and 7 (37%) had contact with tuberculosis patients. Two of the patients (10.5%) were positive for lung tuberculosis, one (5.2%) were tuberculous lymphadenitis and one (5.2%) were tuberculous meningitis. All health personel who were taken to the TB dispensary were found to be positive. Finally, only one of the 19 patients have been working at microbiology laboratory of our hospital who determinate positive test results, and he had a family story of tuberculosis. Conclusion: The Quantiferon Tb gold ELISA test was thought to be a method that could be applied to all healthcare workers, especially healthcare workers who are constantly in contact with patients with tuberculosis. It is also considered appropriate to use of the patient with suspected active tuberculosis infection until culture end.

Latent Tuberculosis Infection Screening Acceptability among Migrant Farmworkers

AbstractLatent tuberculosis (TB) infection is routinely diagnosed using the tuberculin skin test (TST). New methods of detection more specific than TST such as QuantiFERON TB Gold In‐Tube (QFT‐GIT) have been developed but evidence remains limited on their acceptability among migrant farmworkers. This article examined the acceptability of screening tests among migrant farmworkers working on the Arizona‐Mexico border. We conducted a cross‐sectional survey of migrant farmworkers via questionnaire. Of 83 participants interviewed, 53 (63.9%) believed that TB was a serious disease that could result in death and 59 (71.1%) considered TB a health concern in their community. Sixty‐four participants (77.1%) rated QFT‐GIT test as performing better than TST. Our study demonstrates preference for QFT‐GIT results over TST, and highlights migrant farmworkers’ considering themselves at risk of TB and TB as a health concern. Policies that create easy access and culturally appropriate, affordable healthcare for this vulnerable population should be encouraged.

Impact of diabetes mellitus on indeterminate results of the QuantiFERON TB Gold In-Tube test: A propensity score matching analysis.

BackgroundThe sensitivity of interferon-gamma release assays (IGRAs) in the detection of Mycobacterium tuberculosis infection could be affected by conditions of immune dysregulation. For this reason, diabetes mellitus (DM) may increase the frequency of indeterminate results of IGRAs. However, there have been inconsistent reports of role of DM on indeterminate IGRA results.MethodsWe retrospectively reviewed all patients who underwent QuantiFERON-TB Gold In-Tube testing (QFT-GIT) at Chonnam National University Hospital. We collected the clinical and laboratory data of these patients.ResultsOf all 3,391 subjects, 1,265 (37.3%) had a positive QFT-GIT result, 266 (7.8%) had an indeterminate result, and 1,860 (54.9%) had a negative result. The mean age was 54.8 ± 18.1 years and 55.0% of the patients were male. There were 512 (15.1%) patients with DM. Multivariable analysis revealed that systemic corticosteroid use, tuberculosis, lymphocytopenia, low serum albumin, and high serum C-reactive protein (CRP) levels were significantly associated with indeterminate QFT-GIT results. However, DM was not associated with indeterminate QFT-GIT results (adjusted odds ratio, 0.98; 95% confidence interval, 0.69–1.41; P = 0.939). After propensity score matching, DM was not associated with indeterminate results of QFT-GIT.ConclusionIn this large cohort study, DM does not affect the incidence of indeterminate results of QFT-GIT.

Management of long-term therapy with biological drugs in psoriatic patients with latent tuberculosis infection in real life setting.

Psoriatic patients with latent tuberculosis infection (LTBI) need a prophylaxis before starting a treatment with biological drugs. The aim of this study is to investigate the safety and efficacy of prophylaxis of LTBI in psoriatic patients receiving long-term biological drugs. The study included 56 patients (42 male and 14 female) affected by moderate-to-severe psoriasis (mean PASI: 12.8 ± 6.9 SD) treated with anti-TNF-α and/or anti IL 12, 23 and/or anti-CD11 drugs with a diagnosis of LTBI. LTBI diagnosis was based on tuberculin skin test and/or QuantiFERON TB Gold test positivity and chest X-ray suggestive, without clinical, or microbiological evidence of active disease. All patients received prophylactic therapy for 9 months with isoniazid (INH) 300 mg/day, starting 3 weeks before the beginning of biological treatment. Fifty-four patients completed prophylaxis with INH without any adverse events or intolerance; they continue the biological treatment without appearance of active tuberculosis. One patient developed tuberculosis pleurisy in course of treatment with etanercept. The infection has been treated and after a stable remission, treatment was restarted without tuberculosis reactivation. In this retrospective analysis, the prophylaxis of LTBI whit INH was effective and safe in longer follow-up period.

Comparison of the Quantiferon tb gold assay and tuberculin skin test to detect tuberculosis infection among tuberculosis patient contact

Introduction: Tuberculosis is a communicable disease and therefore TB patient contacts are at higher risk of developing TB infection. So screening and diagnosis of latent TB is done by QFT Gold assay and Tuberculin skin test (TST). Methodology: A total of 100 TB patient contacts were taken for study, blood was drawn and processed by using the QFT G assay followed by immediate administration of TST solution in subjects forearm. Data were analyzed and results were compared. Results: QFT G assay detect LTBI with sensitivity of 88.88% and specificity of 90%. TST Sensitivity 68%, Specificity 16%. Conclusions: QFT G Assay have higher detection rate among TB contact patient. Keywords: QFT G quantiferon TB Gold, LTBI- Latent tuberculosis infection, TST – Tuberculin skin test

Prevalence of Latent Mycobacterium Tuberculosis Infection (LTBI) in Saudi Arabia; Population based survey

BackgroundThe annual risk of tuberculosis infection (ARTI) data in Saudi Arabia has not been updated since 1993. ObjectivesTo estimate the prevalence of latent TB infection (LTBI) and ARTI in a population-based sample in Saudi Arabia using Tuberculin skin test (TST) and QuantiFERON TB Gold in tube (QFT-GIT) test. MethodsA population-based cross sectional study was conducted between July 2010 and March 2013. Participants were randomly selected from the population served by the primary healthcare centers of the Ministry of National Guard Health Affairs in Riyadh, Jeddah, Alhassa and Dammam, Saudi Arabia. ResultsA total of 1369 participants were included. The overall prevalence of LTBI was similar using TST and QFT-GIT (9.3% and 9.1% respectively, p=0.872) but stratified prevalence rates were variable in all sociodemographic groups except marital status. Additionally, the prevalence rates of LTBI using either test alone showed significant differences by several sociodemographic and behavioral characteristics. The overall ARTI was 0.36% using TST and 0.35% using QFT-GIT. ConclusionsWe are reporting much lower estimates for the prevalence of LTBI and the ARTI in a population-based sample in Saudi Arabia relative to the data that have been used for more than two decades.

Erratum to: The conversion rate of tuberculosis screening tests during biological therapies in patients with rheumatoid arthritis.

Screening for active tuberculosis (TB) and latent TB infection (LTBI) is mandatory to the initiation of biological therapy in patients with rheumatic diseases. To determine the prevalence of LTBI in patients with rheumatoid arthritis before treatment with biological therapy (anti-TNF, abatacept, and tocilizumab) and the rate of TB conversion during treatment in rheumatoid arthritis (RA) patients, we evaluated the file of 275 patients with RA treated with biological agents. We considered patients with negative baseline TB screening (tuberculin skin test (TST); quantiferon TB gold in tube (QFT-GIT); chest x-ray) and with rescreening for a TB assay every year. Twenty-six patients (10.6%) resulted positive to TB screening at baseline. Two hundred and forty-nine patients (mean age 55.3 ± 11.9; median 55.8 years, range 16–81.9; 210 female) with TB screening negative at baseline were enrolled. One hundred and sixty-eight (67.5%) patients were treated with anti-TNF, 37 (14.9%) patients with abatacept, and 44 (17.7%) patients with tocilizumab. After a period of 12–120 months (median 24), 34 (13.6%) patients displayed conversion of at least one screening assay. Out of the 34 patients with conversion, 6 (16.2%) were treated with abatacept, 7 (15.9%) with tocilizumab, and 21 (12.5%) with anti-TNF. During the follow-up period, no patients developed active TB. Our study shows that a proportion of patients (13.6%) converts at least one TB screening assay during biological therapy. This study underscores the American College of Rheumatology advice for annual screening in some or all biologically treated patients.

High rates of latent TB infection in contacts and the wider community in South India.

We aimed to compare TB transmission rates between case and community households in Vellore, South India. 359 household contacts (HHC) and 363 community contacts (CC) were assessed with tuberculin skin test (TST) and QuantiFERON TB Gold In-Tube test (QFT) between August 2010 and September 2011. Concordance test and multivariate risk factor assessment were conducted using logistic regression adjusted for clustering. Latent TB infection (LTBI) positivity was similar between the two groups using both tests, with only moderate concordance observed between QFT and TST. Children of HHC (<15 years) were at a higher risk for LTBI (odds of 2.37 [1.15-4.89] and 3.02 [1.22-7.45] for TST and QFT respectively). Among adults, both age in decades (odds of 1.33 [1.14-1.15] and 1.16 [1.02-1.32] for TST and QFT, respectively) and the interaction of male gender, smoking and alcohol consumption (odds of 4.06 [1.38-11.93] and 2.59 [1.19-5.64] for TST and QFT, respectively), were associated with increased risk of LTBI. This study provides estimates of TB infection rates accounting for both community and household exposure that contribute to understanding of TB transmission in this setting. We suggest that assessment of risk factors for infection need increased examination as prophylactic treatment of LTBI are being considered.

Role of high-resolution computerized tomography chest in identifying tubercular etiology in patients diagnosed as Eales\u2019 disease

BackgroundThe high resolution computerized tomography of chest is an important diagnostic imaging tool to identify any pulmonary tubercular lesion. It's role in Eales' disease to identify any possible association with pulomonary tuberculosis has not been studied earlier. So, this study was conducted to assess the role of high resolution computerized tomography (HRCT) chest in identifying tuberculous etiology in Eales' disease.ResultsIt was a retrospective study conducted at a tertiary care eye hospital in South India between January 2009 and October 2014 were included. A total of 29 diagnosed cases of Eales' (24 male and 5 female) were included in the study. These patients were followed up for a mean period of 739.75 days. Out of them, 13 (44.8%) had bilateral and 16 (55.2%) had unilateral ocular involvement. Eight cases (34.5%) patients had vitreous inflammation. Mantoux test was positive in 12 (41.4%) cases and chest x-ray suggestive of TB was present in four cases (13.8%). QuantiFERON TB gold was positive in 15 (51.7%) and HRCT chest suggestive of TB was positive in 15 (51.7%) case. Out of 15 Eales' cases with positive HRCT scan suggestive of TB, the commonly noted lesions were calcified nodules 34.5%, mediastinal hilar lymphadenopathy 13.8%, parenchymal soft tissue lesions in 3.4%.Five (17.2%) cases underwent pars plana vitrectomy for non resolving vitreous hemorrhage and one case underwent retinal attachment surgery with encirclage. Six patients were started on 9 months regimen of ATT by the chest physician. Final visual outcome improved in 17(40.5%) eyes, maintained in 21(50%) eyes but vision deterioration in 7(16.7%) eyes.ConclusionsHRCT chest is an important diagnostic tool to rule out pulmonary tuberculosis in Eales’ disease.

Utility of QuantiFERON tuberculosis gold-in-tube test for detecting latent tuberculosis infection among close household contacts of confirmed tuberculosis patients in Accra, Ghana.

Introduction of the interferon gamma (IFN-γ) release assays with their higher sensitivity and specificity over the traditional tuberculin skin test has improved testing for latent tuberculosis infection (LTBI). None of the IFN-γ release assays has ever been used to screen for LTBI in Ghana. This study set out to determine the utility of the QuantiFERON TB Gold-in-Tube (QFT-GIT) test for the diagnosis of LTBI among close household contacts of newly diagnosed sputum smear-positive tuberculosis (TB) patents in Accra, Ghana, and the associated risk factors for a positive QFT-GIT test. Close household contacts of newly diagnosed sputum smear-positive patients receiving anti-TB therapy from three hospitals in Accra were recruited, after providing written informed consent, between April 2012 and December 2014. In addition to demographic details, 2 mL of blood was collected from all participants for the QFT-GIT test for LTBI diagnosis. Out of 112 eligible consenting participants, the QFT-GIT test was performed for 100 participants. The prevalence of LTBI (QFT-GIT positive) was 65%, with 32% being QFT-GIT negative and 3% indeterminate results. Contacts aged >15 years were more likely to be QFT-GIT positive than those aged >15 years, regardless of their Bacillus Calmette-Guerin status. There was significantly higher QFT-GIT test positivity in adult contacts who were parents, siblings, or spouses to index cases than in child contacts (P = 0.0016, P = 0.04, and P = 0.0003, respectively). The QFT-GIT test will be a useful tool for screening of TB contacts for LTBI in Ghana.

Quantiferon conversions and reversions among HIV patients on antiretroviral therapy

BackgroundTuberculosis (TB) remains a major global public health problem. Recent guidelines recommend screening of high-risk patients for latent TB infection, with the preferential use of interferon gamma release assays (IGRA) over PPD. However, there are several reports of reversions and conversion of quantiferon TB tests (QTF).MethodsThe primary aim of this retrospective review among HIV positive patients, >18 years of age, performed from January 2011 to April 2017, was to measure the occurrence of QTF conversions (negative to positive) and reversions (positive to negative) during routine clinical care. Continuous variables will be presented as mean, standard deviation. Categorical variables will be presented as the number and percentage of subjects in each category.ResultsThere were a total of 381 cases, with an average age of 52.8 (±12) years of age. From those 249 patients had at least one QTF performed during the study period and 98 patients had 2 or more tests. 196 had a PPD test performed.From the patients that were initially QTF negative (N = 100), 7 converted to positive.There were a total of 10 patients who’s QTF was positive and were retested, and from those 7 reversed to negative (see Table 1). Most cases that reversed were considered to be low positives (5/6 of those where initial values available).There were 21 patients had a history of positive PPD and 16 of those had negative QTF.ConclusionReversions were common among HIV positive patients with high CD counts. Most reversions occurred with initial low positive QTF results. Providers should consider confirmatory testing among patients with QTF conversion and no history of TB exposure in low-risk settings. Future studies must be done to confirm these findings.AgeCD4 at (+) QTFVL with (+) QTFQTF TB Ag minus Nil value:CD4 at time QTF reversionVL at the QTF reversionAntiretroviral therapy/Latent TB infection treatment56113121.9(+): 2.95 (-): 0.1687742.1Yes/Yes66502<20(+): 1.63 (-): <0.00565<20Yes/Yes70Not done<20(+): 1.04 (-): 0.02Not done<20Yes/Yes61424<20(+): NA (-): 0.07364<20Yes/Yes76766<20(+): 0.37 (-): 0.04Not done<20Yes/No56249<20(+): 0.87 (-): 0.00207<20Yes/No4476338.3(+): 0.72 (-): 0.00664<20Yes/No*TB antigen minus Nil value between 0.35 and 2.0 is a low positive result.Disclosures All authors: No reported disclosures.

Immunodiagnostic Potential of an In-Vitro Interferon-Gamma Release Assay for Latent Tuberculosis Infection Among Apparently Healthy Individuals in Okada Community, Nigeria

A major challenge in the global Tuberculosis (TB) control is the diagnosis and treatment of Latent Tuberculosis Infection (LTBI). In the absence of any reference standard test for the diagnosis of LTBI, this study set out to compare the performance of the two current immune-based tests, Tuberculin Skin Test (TST) and Quantiferon–TB Gold In–Tube (QFT-GIT) ELISA in the diagnosis of LTBI. Two sets of diagnostic results for 196 apparently healthy volunteers from a cross-section of Okada Community, Edo State, Nigeria were compared in terms of age, occupation, BCG-vaccination status, prior TST and cigarette smoking history. Overall, 56 (28.6%) and 81 (41.3%) of the subjects were diagnosed with LTBI by the QFT-GIT test and TST respectively. The LTBI prevalence as assessed by the QFT-GIT test was significantly higher among the non-BCG-vaccinated, compared to the BCG-vaccinees (X²=18.79, df=1, p=0.0001). The highest concordance (QFT-GIT+ve/TST+ve) was found in the occupation categories (Ʀ=-0.009, p=0.747) and the highest discordance(QFT-GIT –ve/TST +ve) was with respect to the BCG-vaccination status (Ʀ=-0.194, p=0.046).The disparity in the performance of the two tests is attributable to the high false – positive TST results, which is a direct reflection of high (90.8%) BCG vaccination level among the study population. It is advocated that the two-step testing approach, using the QFT-GIT assay as a confirmatory test for LTBI after initial positive screening by the TST, be introduced into the TB control strategy in TB – laden communities with high BCG vaccination coverage.

Unusual Causes of Adenopathy in a Tropical Environment: About 3 Observations

Introduction: The discovery of peripheral lymphadenopathy is a frequent reason for consultation and hospitalization in Internal Medicine. The aim of this article is to review through three cases the etiologies of chronic lymphadenopathy rarely reported in a tropical environment. Observations: The first patient is a 62-year-old man who has been infected with HIV-1 for 14 years and who had a multicenter form of Castleman disease. The diagnosis was confirmed after 3 histological lymph nodes. The progression was favorable under Etoposide-based chemotherapy. The second observation is about a 38-year-old woman with a 2-month chronic febrile adenopathy without improvement after anti-tuberculosis treatment. The diagnosis of Kikuchi Fujimoto disease, in its necrotizing form, was confirmed in histology. The evolution was made favorable by the corticosteroid therapy. The third observation is about a 63-year-old woman with an enlargement of groups of lymph nodes, liver, and spleen. This tumoral syndrome was associated to an exudative ascites and a Systemic Inflammatory Response Syndrome (SIRS). The initial diagnosis was a multifocal tuberculosis based on a set of evidence (exudative lymphocytic ascites, epidemiological context and a positive Quantiferon TB test). The first ganglionic histology was not contributory. It was the second ganglionic histology that indicated the diagnosis of lymph node plasmocytoma revealing a myeloma. The patient died of septic shock. Conclusion: In tropical environment, the etiologies of chronic lymphadenopathy are not limited to tuberculosis and malignant haemopathies. Carrying out ganglionic histology is an absolute necessity.

The conversion rate of tuberculosis screening tests during biological therapies in patients with rheumatoid arthritis.

Screening for active tuberculosis (TB) and latent TB infection (LTBI) is mandatory to the initiation of biological therapy in patients with rheumatic diseases. To determine the prevalence of LTBI in patients with rheumatoid arthritis before treatment with biological therapy (anti-TNF, abatacept, and tocilizumab) and the rate of TB conversion during treatment in rheumatoid arthritis (RA) patients, we evaluated the file of 275 patients with RA treated with biological agents. We considered patients with negative baseline TB screening (tuberculin skin test (TST); quantiferon TB gold in tube (QFT-GIT); chest x-ray) and with rescreening for a TB assay every year. Twenty-six patients (10.6%) resulted positive to TB screening at baseline. Two hundred and forty-nine patients (mean age 55.3±11.9; median 55.8years, range 16-81.9; 210 female) with TB screening negative at baseline were enrolled. One hundred and sixty-eight (67.5%) patients were treated with anti-TNF, 37 (14.9%) patients with abatacept, and 44 (17.7%) patients with tocilizumab. After a period of 12-120months (median 24), 34 (13.6%) patients displayed conversion of at least one screening assay. Out of the 34 patients with conversion, 6 (16.2%) were treated with abatacept, 7 (15.9%) with tocilizumab, and 21 (12.5%) with anti-TNF. During the follow-up period, no patients developed active TB. Our study shows that a proportion of patients (13.6%) converts at least one TB screening assay during biological therapy. This study underscores the American College of Rheumatology advice for annual screening in some or all biologically treated patients.

Predictors of low prevalence of latent tuberculosis infection among Egyptian health care workers at intensive care and bronchoscopy units.

Aim: Latent tuberculosis infections (LTBI) contain a significant reservoir for future epidemics. Screening of health care workers (HCWs) in a high-risk tuberculosis (TB) environment is an important strategy in TB control. The study aimed to assess the prevalence of LTBI among high risk Egyptian HCWs and to assess infection associated risk factors.Methods: Fifty-two HCWs who work at intensive care unit (ICU), bronchoscopy unit, and chest diseases department were tested for LTBI using both tuberculin skin test (TST) and Quantiferon TB Gold in-tube test (QFT). Risk factors for infection, knowledge of HCWs towards different aspects of TB infection and agreement between TST and QFT were also evaluated.Results: Prevalence of LTBI in this study was 13.5% by QFT and TST. It was 13.6% by TST alone and 10.3% by QFT alone. There was good concordance between both tests (Kappa=0.713). There was a statistically significant association between prevalence of LTBI and age of staff ≥30 yr (p=0.002), period of working experience (p=0.006) and working at the Bronchoscopy Unit (p=0.001). The total knowledge of HCWs towards different aspects of TB infection was generally good. Conclusion: Although the participants in the current study were among high risk HCWs, the prevalence of LTBI was low. Bacille Calmette-Guerin (BCG) vaccination, young age, short employment duration, good knowledge and a good infection control were the predictors of low risk of contracting TB at our hospitals. The risk of TB infection in resource-limited countries can be reduced with simple continuous educational and administrative infection control programmes.

Tuberculosis: Is the landscape changing?

Robert Heinrich Herman Koch, a German physician and microbiologist, received Nobel Prize in 1905 for identifying the specific causative agent of tuberculosis (TB). During his time it was believed that TB was an inherited disease. However he was convinced that the disease was caused by a bacterium and was infectious, tested his postulates using guinea pigs, and found the causative agent to be slow growing mycobacterium tuberculosis. TB is the second most common cause of death from infectious diseases after HIV/AIDS. Drug-resistant TB poses serious challenge to effective management of TB worldwide. Multidrug-resistant TB accounted for about half a million new cases and over 200,000 deaths in 2013. Whole-genome sequencing (first done in 1998) technologies have provided new insight into the mechanism of drug resistance. For the first time in 50 y, new anti TB drugs have been developed. The World Health Organization (WHO) has recently revised their treatment guidelines based on 32 studies. In United States, latent TB affects between 10 and 15 million people, 10% of whom may develop active TB disease. QuantiFERON TB Gold and T-SPOT.TB test are used for diagnosis. Further research will look into the importance of newly discovered gene mutations in causing drug resistance.