Positive GeneXpert Research Articles

The Concordance between GeneXpert MTB/RIF and Isothermal Amplification Assay for Detecting Mycobacterium tuberculosis

Tuberculosis (TB) is an infectious disease and one of the biggest causes of death worldwide. The main problem today is the lack of accurate and rapid tests to detect Mycobacterium tuberculosis (MTB). Several molecular methods have been developed to detect MTB. GeneXpert MTB/RIF® can detect MTB and rifampicin resistance simultaneously in <2 hours. Cross Priming Amplification (CPA) is one of the isothermal amplification assay methods that can detect MTB. Both of these methods are molecular rapid tests so they can detect MTB faster. This study aims to evaluate the concordance of GeneXpert MTB/RIF® results with CPA to detect MTB at Hasan Sadikin General Hospital, Bandung. This is an observational cross-sectional study. The subjects were patients with suspected pulmonary TB and examined with GeneXpert MTB/RIF® then CPA (Ustar EasyNAT MTC™) was also examined. This study used total sampling with 50 subjects and analyzed with Cohen's Kappa test. The results of GeneXpert MTB/RIF® and Ustar EasyNAT MTC™ in detecting MTB obtained Kappa of 0.662 (good agreement) with p-value <0.001. Of the 11 low positive samples on GeneXpert MTB/RIF® as many as 6 subjects (54.55%) had positive results, and 5 subjects (45.45%) had negative results on UStar EasyNAT MTC™. Meanwhile, of the 4 very low positive samples, there was only 1 sample with positive results on UStar EasyNAT MTC™. There is a match results between high and medium positive GeneXpert MTB/RIF® and UStar EasyNAT MTC™. However, there is a difference between low and very low positive results on GeneXpert MTB/RIF® and UStar EasyNAT MTC™.

Diagnostic Value of Targeted Next-generation Sequencing in Pulmonary Mycobacterial Infections.

This study aimed to explore the diagnostic value of novel technique-targeted next-generation sequencing (tNGS) of bronchoalveolar lavage fluid (BALF) in pulmonary mycobacterial infections. This retrospective study was conducted on patients who underwent bronchoscopy and tNGS, smear microscopy, and mycobacterial culture of BALF. Patients with positive Mycobacterium tuberculosis (MTB) culture or GeneXpert results were classified into the tuberculosis case group. Those diagnosed with nontuberculous mycobacteria (NTM)-pulmonary disease (NTM-PD) composed the case group of NTM-PD patients. The control group comprised patients without tuberculosis or NTM-PD. Sensitivity, specificity, and receiver operating characteristic (ROC) curves were used to evaluate the diagnostic performance. For tuberculosis patients with positive mycobacterial culture results, the areas under the ROC curves (AUCs) for tNGS, GeneXpert, and smear microscopy were 0.975 (95% CI: 0.935, 1.000), 0.925 (95% CI: 0.859, 0.991), and 0.675 (95% CI: 0.563, 0.787), respectively. For tuberculosis patients with positive GeneXpert results, the AUCs of tNGS, culture, and smear microscopy were 0.970 (95% CI: 0.931, 1.000), 0.850 (95% CI: 0.770, 0.930), and 0.680 (95% CI: 0.579, 0.781), respectively. For NTM-PD, the AUCs of tNGS, culture, and smear-positive but GeneXpert-negative results were 0.987 (95% CI: 0.967, 1.000), 0.750 (95% CI: 0.622, 0.878), and 0.615 (95% CI: 0.479, 0.752), respectively. The sensitivity and specificity of tNGS in NTM-PD patients were 100% and 97.5%, respectively. tNGS demonstrated superior diagnostic efficacy in mycobacterial infection, indicating its potential for clinical application.

Successful Management of Miliary Tuberculosis with Concomitant Anemia: A Case Report

Background: Miliary tuberculosis (TB) is a disseminated and potentially fatal form of TB characterized by the hematogenous spread of Mycobacterium tuberculosis, often complicated by anemia of chronic disease. The diagnosis and management of miliary TB, particularly in conjunction with anemia, can be challenging, especially in resource-limited settings. Case presentation: We report the case of a 20-year-old male from a remote region in Eastern Halmahera, Indonesia, who presented with progressive shortness of breath, productive cough, night sweats, unintentional weight loss, and generalized weakness. Clinical examination revealed signs of anemia and respiratory distress. Laboratory investigations confirmed microcytic hypochromic anemia and a positive GeneXpert MTB/RIF test. Chest radiography demonstrated diffuse miliary nodules, consolidation, and cavitation, establishing the diagnosis of miliary TB with concomitant anemia. The patient received a standard six-month anti-tuberculosis therapy regimen, along with supportive care and targeted treatment for anemia and associated symptoms. The patient demonstrated significant clinical and hematological improvement, leading to discharge after 11 days of hospitalization. Follow-up assessments confirmed continued progress and the absence of complications. Conclusion: This case underscores the critical importance of maintaining a high index of suspicion for miliary TB in patients presenting with respiratory and constitutional symptoms, even in the absence of traditional risk factors. The presence of anemia can further complicate the clinical picture. Prompt diagnosis through a combination of clinical assessment, laboratory investigations, and imaging studies, followed by the immediate initiation of appropriate treatment, including the management of anemia, is paramount for achieving favorable outcomes in patients with miliary TB. The case also emphasizes the necessity for comprehensive care and follow-up to ensure sustained recovery and prevent relapse.

Etiological Spectrum of Lymphadenopathy Among Children on Lymph Node Biopsy.

Background Pediatric peripheral lymphadenopathy is commonly a benign condition and most cases resolve spontaneously; however, it can be a manifestation of a serious underlying disease. This study aimed to determine the etiological spectrum of persistent pediatric lymphadenopathy on excisional biopsy in a tertiary care children's hospital in a low-middle-income country and to make recommendations regarding evaluation, diagnostic testing, and surgical interventions best suited to the population. Methodology A prospective cross-sectionalstudy was conducted on 243 pediatric patients between the ages of one to 12 years undergoing excisional biopsy for persistent lymphadenopathy (more than four weeks duration) from April 1, 2021, to March 31, 2024. Patient demographic data along with signs, symptoms, and results of investigations including histopathological diagnosis were documented on a structured proforma. Results Patients' age range was two to 12 years (mean = 7.29 ± 2.30 years). The male-to-female ratio was 1:53. The Mean duration of lymphadenopathy was 35.89 ± 6.95 days (range = 25 to 57 days). The average size of lymph nodes ranged from 1 cm to a complex nodal mass of 7 cm. Histopathology showed reactive hyperplasia (40.32%, n = 98), tuberculosis (TB) (33.7%, n = 82), lymphoma (10.3%, n = 25), atypical mycobacterial adenitis (6.99%, n = 17), chronic granulomatous inflammation-histiocytosis (6.2%, n = 15), and Langerhans cell histiocytosis (2.5%, n = 6). The most common site was cervical. Sputum GeneXpert for TB had a true-positive rate of 78.84% while PPD was positive in only 13 TB patients. Atypical mycobacterial adenitis was successfully treated with excision and antibiotics. Supraclavicular nodes were strongly associated with lymphoma (p = 0.008). Conclusions Persistent pediatric lymphadenopathy is most commonly caused by TB followed by lymphoma. Positive sputum GeneXpert for TB with a suggestive clinical picture in endemic regions may be sufficient to start empiric therapy without the need for excisional biopsy in mycobacterial TB adenitis with negative PPD results and normal chest X-ray. In all other cases, excisional biopsy remains the gold standard for diagnosis. However, further studies should be conducted to formulate less invasive management algorithms.

Thyroid tuberculosis mimicking multinodular goiter: a case report

BackgroundMycobacterium tuberculosis is the second most common infectious cause of death in adults worldwide. The ability of this organism to efficiently establish latent infection has enabled it to spread to nearly one-third of individuals worldwide. Approximately 8 million new cases of active tuberculosis disease occur each year, leading to about 1.7 million deaths. The disease incidence is magnified by the concurrent epidemic of human immunodeficiency virus infection. A total of 1.3 million people died from tuberculosis in 2022. In 2022, an estimated 10.6 million people fell ill with tuberculosis worldwide, including 5.8 million men, 3.5 million women, and 1.3 million children. We report a case of thyroid tuberculosis presenting as multinodular goiter. Neck ultrasound was done and revealed abscess collection on the background of multinodular colloid goiter. The diagnosis of thyroid tuberculosis was confirmed by a positive GeneXpert of the pus sample and the presence of extensive caseous necrosis on cytopathology examination. Furthermore, anterior neck swelling may provide a diagnostic challenge by clinically mimicking multinodular goiter or thyroid neoplasms. Owing to its rarity and its tendency to pose a clinical diagnostic challenge, we decided to report it.Case presentationA 60-year-old retired female Ethiopian high-school teacher presented to University of Gondar Hospital, Gondar, Ethiopia with firm, nontender multinodular anterior neck swelling measuring at largest 2 × 3 cm that moves with swallowing. GeneXpert of the pus sample and cytopathology examination confirmed the diagnosis of thyroid tuberculosis, and the patient was started on 2 rifampicin−ethambutol−isoniazid−pyrazinamide/4 rifampicin−isoniazid 3 tablets by mouth/day, which is defined as the preferred first-line anti-tuberculosis regimen in Ethiopia, and pyridoxine 50 mg by mouth per day for 6 months. Since then, she has been followed with regular liver function tests. The patient has shown a smooth course with no significant adverse effects encountered. Currently, the patient has completed her anti-tuberculosis treatment and is doing well.ConclusionIn the clinical evaluation of a patient with anterior neck swelling, tuberculosis must be considered as a differential diagnosis in subjects from endemic areas for early diagnostic workup and management.

Challenges and knowledge gaps in the management of non-tuberculous mycobacterial pulmonary disease in sub-Saharan African countries with a high tuberculosis burden: a scoping review

IntroductionIn sub-Saharan African (SSA) countries endemic for tuberculosis (TB), previous TB is a significant risk factor for non-tuberculous mycobacterial pulmonary disease (NTM-PD). The deployment of GeneXpert MTB/RIF in pulmonary TB...

Paradoxical reaction in peripheral lymph node tuberculosis: a review for its prevalence, clinical characteristics, and possible treatment.

The paradoxical reaction (PR) is a transient worsening following tuberculosis treatment and it is not uncommon in lymph node tuberculosis (LNTB). PR in LNTB maybe wrongly considered as treatment failure or relapse. This review was undertaken to address various aspects of PR associated with lymph node tuberculosis prevalence, underlying mechanism, clinical pattern, predictors, and possible treatment in an immunocompetent individual. A literature review was performed using various databases (PubMed, Scopus, Science Direct, and Google Scholar) to identify relevant articles for review. The prevalence of paradoxical reactions associated with LNTB varies from as low as 13.3% to as high as 35.3% PR may occur during antitubercular treatment or be reported even after completion of treatment called post-therapy PR. An onset of PR may occur within a month of therapy to even 12 months from the initiation of an anti-tubercular drug. Delayed hypersensitivity reaction and reduction in immune suppression is believed to be possible mechanism leading to a paradoxical reaction. PR in LNTB is characterized by either progression of pre-existing nodal enlargement or formation of abscess, sinus formation, or appearance of new nodal enlargement or rarely extra-nodal involvement. PR is a diagnosis of exclusion and may show granuloma, positive AFB smear, or positive GeneXpert but AFB culture is always negative. Younger age, lymph node size of equal to or more than 3 cm, female gender, unilateral lymphadenopathy, and those with positive AFB on initial examination are predictors for PR in peripheral LNTB. The majority of PR in LNTB have a mild course and are generally self-limited.

Role of GeneXpert in Diagnosis of Smear Negative Pulmonary Tuberculosis

Abstract Background Pulmonary TB considered as a global health problem with specific concern in developing countries that need rapid methods in diagnosis with accurate results. Objective To evaluate the diagnostic yield of GeneXpert assay in diagnosis of TB infection in patients with negative sputum smear. Methods A total 346 cases with suspect clinical and radiological finding for TB infection was subjected to direct sputum analysis under microscope to find acid fast bacilli (AFB); the negative smear then subjected to GeneXpet assay analysis and sputum culture on LJ media. Results All cases with negative GeneXpert results, had negative culture, while 45 cases of 50 that had positive GeneXpert assay finding showed positive culture. The diagnostic yield of test was excellent (94.7%). The sensitivity, specificity, PPV and NPV were 100, 89.8, 90 and 100 respectively. Conclusion The performance of GeneXpert assay in diagnosing TB among smear negative patients was reasonable, and may fast the decision of treatment.

Gene Xpert MTB/RIF assay in patients with clinical suspicion of tuberculous meningitis

Early diagnosis and treatment of tubercular meningitis (TBM) is one of the best predictors of survival. The smear testing of the cerebrospinal fluid (CSF) has a low sensitivity and cultures, though having higher sensitivity, take a long time in TBM diagnosis. The present study was done to evaluate the proportion of positive Gene Xpert test, a rapid nucleic acid amplification test, in clinically suspected patients with TBM. The results of Gene Xpert tests were then compared with the culture results. One hundred and fifty prospective patients with a clinical suspicion of TBM were classified as probable or possible TBM and underwent CSF examination for culture and Gene Xpert assay. Out of 124 patients available for statistical evaluation, 52 were in the probable and 72 in possible TBM group. The proportion of patients with Gene Xpert positivity were significantly more in probable compared to possible TBM (63.15% vs 36.85%, p<0.001). Twenty-eight patients had a positive culture result. The sensitivity of Gene Xpert relative to culture testing was 68.42%, specificity of 97.61%, a positive predictive value of 92.85% and a negative predictive value of 87.23%. Gene Xpert testing provided a rapid diagnosis in patients suspected with TBM. The high sensitivity and specificity of this test relative to culture testing is a strong indication that it should be included as one of the gold standard tests in patients with suspected TBM.

Head-to-head comparison of diagnostic accuracy of four Ebola virus disease rapid diagnostic tests versus GeneXpert® in eastern Democratic Republic of the Congo outbreaks: a prospective observational study

Ebola virus disease (EVD) outbreaks have emerged in Central and West Africa. EVD diagnosis relies principally on RT-PCR testing with GeneXpert®, which has logistical and cost restrictions at the peripheral level of the health system. Rapid diagnostic tests (RDTs) would offer a valuable alternative at the point-of-care to reduce the turn-around time, if they show good performance characteristics. We evaluated the performance of four EVD RDTs against the reference standard GeneXpert® on stored EVD positive and negative blood samples collected between 2018 and 2021 from outbreaks in eastern Democratic Republic of the Congo (DRC). We conducted a prospective and observational study in the laboratory on QuickNavi-Ebola™, OraQuick® Ebola Rapid Antigen, Coris® EBOLA Ag K-SeT, and Standard® Q Ebola Zaïre Ag RDTs using left-over archived frozen EDTA whole blood samples. We randomly selected 450 positive and 450 negative samples from the EVD biorepositories in DRC, across a range of GeneXpert® cycle threshold values (Ct-values). RDT results were read by three persons and we considered an RDT result as "positive", when it was flagged as positive by at least two out of the three readers. We estimated the sensitivity and specificity through two independent generalized (logistic) linear mixed models (GLMM). 476 (53%) of 900 samples had a positive GeneXpert Ebola result when retested. The QuickNavi-Ebola™ showed a sensitivity of 56.8% (95% CI 53.6-60.0) and a specificity of 97.5% (95% CI 96.2-98.4), the OraQuick® Ebola Rapid Antigen test displayed 61.6% (95% CI 57.0-65.9) sensitivity and 98.1% (95% CI 96.2-99.1) specificity, the Coris® EBOLA Ag K-SeT showed 25.0% (95% CI 22.3-27.9) sensitivity and 95.9% (95% CI 94.2-97.1) specificity, and the Standard® Q Ebola Zaïre Ag displayed 21.6% (95% CI 18.1-25.7) sensitivity and 99.1% (95% CI 97.4-99.7) specificity. None of the RDTs evaluated approached the "desired or acceptable levels" for sensitivity set out in the WHO target product profile, while all of the tests met the "desired level" for specificity. Nevertheless, the QuickNavi-Ebola™ and OraQuick® Ebola Rapid Antigen Test demonstrated the most favorable profiles, and may be used as frontline tests for triage of suspected-cases while waiting for RT-qPCR confirmatory testing. Institute of Tropical Medicine Antwerp/EDCTP PEAU-EBOV-RDC project.

Disseminated tuberculosis presenting as a crescentic glomerulonephritis

A 48-year-old male patient presented with dialysis dependent renal failure with biopsy showing crescentic glomerulonephritis and Positron emission tomography–computed tomography (PET-CT scan) revealing features of pericardial, pulmonary tuberculosis with positive urinary GeneXpert test for tuberculosis bacilli. Clinicians should keep in mind the atypical presentations of tuberculosis while managing rapidly progressive renal failure especially in tropical countries with high prevalence of tuberculosis.

Surgical Intervention for Endobronchial Tuberculosis with Total Bronchial Occlusion: A Case Report

Introduction. Endobronchial Tuberculosis (EBTB) is a specific TB form affecting the tracheobronchial tree with microbial and histopathological evidence. Early diagnosis is essential to provide timely treatment and prevent complications but also proves difficult due to the low positive rate of acid–fast bacilli (AFB) staining of sputum smears and non–specific clinical and radiological findings. Case Illustration. We reported a 19–year–old man with a productive cough suspected of pulmonary tuberculosis, with a positive GeneXpert test and negative AFB smear. He received anti–tuberculosis drugs for six months. Although the symptoms initially seemed to improve, the patient complained of dyspnea during moderate activities in the sixth month. Chest x–ray showed complete atelectasis of the left lung. Further investigation with thorax computed tomography and confirmation with bronchoscopy revealed total occlusion of the left main bronchus. Left pneumonectomy was successfully conducted. Conclusion. Endobronchial tuberculosis may progress to an advanced stage despite adequate anti–tuberculosis drugs. Therefore, early diagnostic strategies are required to prevent the progression of the disease, particularly due to the insidious nature of its pathophysiological process

P258 Incidence of Histoplasmosis, Cryptococcosis, and TB Among People Living with HIV in Paraguay-Preliminary Report

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PMObjectivesEndemic fungal infections such as Histoplasmosis and Cryptococcosis as well as tuberculosis (TB) are important causes of mortality among people living with HIV (PLHIV) in Latin America. Rapid diagnostic assays (RDAs) could decrease the time to diagnosis and treatment of these infections, resulting in a reduction in mortality. The objectives of this study were to determine the incidence of Histoplasmosis, Cryptococcosis, and TB using RDAs in PLHIV with advanced HIV disease (AHD) and calculate 30-day mortality.MethodsPLHIV 18 years and older, treated at the Institute of Tropical Medicine hospital in Asuncion, Paraguay, not receiving ART and presenting CD4 count ≤ 200 cells/μL or clinical symptoms suggestive of WHO stage 3 or 4 diseases were enrolled and followed for 30 days. Detection of Histoplasma Ag (HisAg) in urine was performed by enzyme immunoassay (EIA), Cryptococcus Ag (CrAg) detection in serum and cerebrospinal fluid specimens by lateral flow assay (LFA), and liparabinomannan (LAM) detection in urine by LFA (TB LAM) (limited to those patients with CD4 counts ≤ 100 cells/μL) and by GeneXpert (limited to patients with respiratory symptoms).ResultsFrom August 2021 to 25 March 2022, a total of 335 PLHIV were enrolled. Patient median age was 37 years [Interquartile Range (IQR) 16 years], median CD4 count at enrollment was 91 cells/μL (IQR 147 cell/μL). A total of 80% (n = 269) of patients were symptomatic for one or more of the three diseases being screened for. Ag positivity rate was 20% (40/196) for TB-LAM, 10% (32/314) for HisAg, and 11% (35/329) for CrAg (15 diagnosed with cryptococcal meningitis). GeneXpert testing showed a positivity of 14% (15/108), and six of these patients with positive GeneXpert also tested positive for TB-LAM.In total, 100/335 (30%) of patients tested had a positive result and coinfections were observed among 14/335 (4.2%) patients (Table 1). Histoplasmosis + TB was the most frequent co-infection observed 12/335 (3.6%).Mortality among those who completed 30-day follow-up was 12.6% (32/254) and 11% among those with an OI (11/102)Conclusions: Preliminary results show that TB and fungal opportunistic infections, including co-infection were common in people with advanced HIV. Longitudinal follow-up will help to evaluate the feasibility and cost of implementing RDAs for the early detection of opportunistic infections in PLHIV with AHD in Paraguay. Early diagnosis could impact mortality reduction.

Yield of gene Xpert in diagnosing patients with pleural tuberculosis presenting to a tertiary care hospital

BACKGROUND & OBJECTIVE: Pleural tuberculosis is a common type of extrapulmonary tuberculosis and remains a common problem for pulmonologists. Early detection of tuberculosis is a global priority for TB control. Gene Xpert is a real-time PCR, which can reveal Mycobacterium tuberculosis within 2 hours. This study will bridge the gap and help the pulmonologist for deciding on the use of Gene Xpert as diagnostic tool for pleural tuberculosis. Our objective is to find the frequency of positive Gene Xpert among patients of pleural tuberculosis presenting to tertiary care hospital.
 METHODOLOGY: A Cross-sectional study was conducted in the Department of Pulmonology, Aziz Fatima Hospital, Faisalabad from 26 February 2022 to 25 March 2022. Total 187 patients ages between 15-80 years having pleural tuberculosis diagnosed during last 6 months were included in the study. Patients already taking anti-tuberculosis therapy were excluded. Pleural fluid was processed in Aziz Fatima Hospital, Faisalabad laboratory for Gene Xpert immediately. Reports were collected next day and noted in the proforma. Positive Gene Xpert as per operational definition. Data was stratified for variables like age, gender, comorbidities (like diabetes mellitus, HIV and smoking status). Chi-square test was applied taking p-value ≤ 0.05 as significant.
 RESULTS: Out of 187 patients, mean age was 43.71±14.93 years. 95(50.8%) patients were male and 92(49.2%) patients were females. Positive Gene Xpert was found in 49(26.2%) patients. Positive Gene Xpert is more common in patients of HIV positive 27 (38.6%) than the 22 (18.8%) patients of HIV negative shows significant association (p-value = 0.001). Out of 72 diabetic patients, 23(31.9%) patients had positive Gene Xpert and out of 115 non-diabetic patients, 26(22.6%) patients had positive Gene Xpert with p-value = 0.158. Out of 82 smoker patients, 27(32.9%) patients had positive Gene Xpert and out of 105 non-smoker patients, 22(21%) patients had positive Gene Xpert with p-value=0.065. Out of 57 HIV positive patients, 27(47.4%) patients had positive Gene Xpert and out of 130 HIV negative patients, 22(16.9%) patients had positive Gene Xpert with p-value =0.001.
 CONCLUSION: Gene Xpert can be used as a reliable investigation for detection of pleural tuberculosis and timely initiation of treatment.

An evaluation of Composite Reference Standard (CRS) for diagnosis of Female Genital Tuberculosis

BackgroundFemale genital tuberculosis (FGTB) is a common cause of infertility in developing countries. Its diagnosis is difficult due to its paucibacillary nature, with no single test having high sensitivity and specificity. This study is to share the experience of using Composite Reference Standard (CRS) for the diagnosis of FGTB. MethodsThis is a prospective study conducted between September 2017 to June 2019, over 100 infertile females found to have FGTB on composite reference standard which consisted of acid-fast bacilli on microscopy or culture, histopathological evidence of epithelioid granuloma, positive gene Xpert on endometrial sample or definite or probable finding of FGTB on laparoscopy. ResultsA total of 100 infertile women (78% primary, 22% secondary) found to have FGTB on CRS were enrolled in this study. Mean age, body mass index, parity and duration of infertility were 28.2 years, 23.17 kg/m2, 0.24 ± 0.12 and 2.41 years respectively. Various symptoms were scanty menses (16%), irregular cycle (7%), dysmenorrhea (11%), pelvic pain (11%). Various signs were vaginal discharge (65%), adnexal mass (6%), tubo-ovarian mass on ultrasound (15%), abnormal hysterosalpingography findings (57.14%), positive polymerase chain reaction test (65%) and abnormal hysteroscopy (82.2%). The positive findings on CRS were positive AFB on microscopy or culture (3%), positive gene Xpert (28%) (done in some cases), epithelioid granuloma on histopathology (13%), definite findings on laparoscopy like tubercles, caseous nodules and beaded tubes in (57.19%) patients while probable findings of FGTB like straw colored fluid in POD, extensive dense pelvic, peri-tubal, peri-ovarian adhesions; hydrosalpinx; tubo-ovarian mass; thick fibrosed tubes; mid tubal block; peri hepatic adhesions (Fitz Hugh Curtis Syndrome); hyperemia of tubes/blue uterus on chromotubation were seen in (48.8%) patients. All patients found to be positive on CRS were given 6 months of anti-tubercular therapy. ConclusionThis study demonstrates the high reliability of use of composite reference standard for diagnosis of FGTB.

Suppurative complications following BCG vaccine in 2 Nepalese children

BackgroundThe Bacillus Calmette–Guérin (BCG) vaccine is one of the most common vaccines administered worldwide and awareness regarding its usual and adverse reactions is important. Local and systemic complications require accurate identification for timely therapy. We hereby report two patients with rare suppurative local complications of BCG. Case presentationCase 1: A nine-month-old boy presented with swelling over the right deltoid for one month with low-grade fever and purulent discharge for two days. The active discharge occurred from the same site of previous BCG inoculation, the regression of which was achieved conservatively. Case 2: The second case was a 14-month-old boy who presented with a swelling over the lower part of the right axilla for one year, later diagnosed as a tuberculous lymph nodal abscess. Needle aspiration was done and anti-tubercular therapy was started based on positive Gene Xpert reports. Both the cases resolved completely without complications. ConclusionPharmacovigilance surveillance of BCG scar reactions and occurrence of suppurative complications should be known by clinicians for correct identification and management.

Field performance of three Ebola rapid diagnostic tests used during the 2018–20 outbreak in the eastern Democratic Republic of the Congo: a retrospective, multicentre observational study

The Democratic Republic of the Congo has confronted 13 outbreaks of Ebola virus disease since 1976. Rapid diagnostic tests (RDTs) detecting viral antigens have been developed to circumvent difficulties encountered with RT-PCR for diagnosis in remote low-resource settings, but there is still uncertainty about their performance characteristics and usability during outbreaks. We aimed to assess the field performance of three antigen detection RDTs compared with the gold-standard Cepheid GeneXpert Ebola assay results. We conducted a retrospective, multicentre observational study using complete and de-identified databases of five mobile laboratories (managed by the Institut National de Recherche Biomédicale) to assess the performance of three Ebola virus disease RDTs (QuickNavi-Ebola, OraQuick Ebola Rapid Antigen Test, and Coris EBOLA Ag K-SeT rapid test) run on blood samples of patients with suspected Ebola virus disease in direct comparison with the Cepheid GeneXpert Ebola assay reference test during the 2018-20 outbreak in the eastern Democratic Republic of the Congo. We estimated the sensitivity and specificity of each test through generalised linear mixed models against the GeneXpert Ebola assay reference test and corrected for cycle threshold value and random site effects. 719 (7·9%) of 9157 samples had a positive GeneXpert Ebola assay result. The QuickNavi-Ebola RDT had a sensitivity of 87·4% (95% CI 63·6-96·8) around the mean cycle threshold value and a specificity of 99·6% (99·3-99·8). The OraQuick Ebola Rapid Antigen Test had a sensitivity of 57·4% (95% CI 38·8-75·8) and specificity of 98·3% (97·5-99·0), and the Coris EBOLA Ag K-SeT rapid test had a sensitivity of 38·9% (23·0-63·6) against the GeneXpert Ebola assay reference and specificity of 97·4% (85·3-99·6). The QuickNavi-Ebola RDT showed a robust performance with good sensitivity, particularly with increasing viral loads (ie, low cycle threshold values), and specificity. The three RDTs evaluated did not achieve the desired sensitivity and specificity of the WHO target product profile. Although the RDTs cannot triage and rule out Ebola virus infection among clinical suspects, they can still help to sort people with suspected Ebola virus disease into high-risk and low-risk groups while waiting for GeneXpert Ebola assay reference testing. None. For the French translation of the abstract see Supplementary Materials section.

Hysterosalpingography Observations in Female Genital Tuberculosis with Infertility.

Hysterosalpingography (HSG) is radiographic evaluation of uterine cavity and tubal patency. The aim of this study was to evaluate the safety and utilisation of HSG in female genital tuberculosis (FGTB) with infertility. The study was conducted in a tertiary referral centre of North India. It was a prospective study on 87 cases of FGTB with infertility. Diagnosis of FGTB was made by composite reference standard using the presence of acid-fast bacilli on microscopy/culture or positive GeneXpert, positive polymerase chain reaction or epithelioid granuloma on endometrial biopsy or definitive or probable findings on laparoscopy or hysteroscopy. Suitable statistical methods were used with STATA software version 12.0. HSG findings were normal in 49 (56.32%) cases. There were filling defects in 14 (16.09%), short and shrunken cavity in 4 (4.49%), intrauterine synechiae in 14 (16.09%), T-shaped cavity in 3 (3.44%) and deformed uterine cavity in 5 (5.74%) cases. Fallopian tube findings were hydrosalpinx in 12 (13.79%) and 11 (12.64%) cases, beading of tube in 4 (4.59%) and 2 (2.29%) cases, pipestem appearance in 2 (2.29%) cases each and Maltese cross appearance in 3 (3.44%) and 2 (2.29%) cases, respectively. Tubal blockage was seen in 69 (79.31%) and 67 (77.01%) cases being cornual block in 28 (32.18%) and 26 (29.88%) cases, mid-tubal block in 16 (18.39%) and 15 (17.24%) cases, multiple blocks in 10 (11.49%) and 12 (13.79%) cases and fimbrial block in 15 (17.24%) and 14 (16.09%) cases. None of the cases had flare-up of the disease after HSG in the current study. HSG is a useful modality in FGTB with infertility.

Agreement test between Ziehl Neelsen staining and GenXpert in adult pulmonary tuberculosis diagnosis

Background: Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (MTB). Most of healthcare facilities in Indonesia still use Ziehl Neelsen (ZN) staining to diagnose pulmonary tuberculosis (TB) rather than GeneXpert MTB/RIF. However, the agreement between both methods is not well established.Objective: This study aims to observe levels of agreement between ZN staining and GeneXpert MTB/RIF in diagnosing adult pulmonary TB at Dr. Mohammad Hoesin General Hospital (RSMH) Palembang.Methods: This study was a retrospective comparative analytical study using an agreement test. Its samples were patient specimens for a period of January 2016 - March 2017 which were examined by ZN staining and GeneXpert MTB/RIF to diagnose pulmonary TB at the Clinical Pathology and Microbiology Installation of RSMH Palembang. Its data were obtained from laboratory results of ZN staining and GeneXpert MTB/RIF. Then, Cohen’s Kappa was used to measure the levels of agreement between both the assays.Results: Of 150 specimens, 69.3% were from male patients and 30.7% were from female patients with mean age of 46.71±14.57. Both ZN staining and GeneXpert positivity were 57.3%. 0.05% of positive GeneXpert MTB/RIF were negative ZN smear, while 0.06% of negative GeneXpert were positive ZN smear. The Cohen’s Kappa coefficient was 0.893 indicating a very good agreement.Conclusion: This study found that there was a very good agreement between ZN staining and GeneXpert MTB/RIF in diagnosing adult pulmonary TB at the RSMH Palembang.

798. Incomplete Contact Investigation and Risk of Developing Tuberculosis Among Healthcare Professionals After Tuberculosis Exposure

BackgroundTuberculosis (TB) contact investigation is recommended for healthcare professionals (HCPs) after TB exposure. However, association between no participation in or incomplete contact investigation and subsequent TB development has not been well-described. This study aims to determine TB incidences and factors associated with TB development among HCPs requiring contact investigations.MethodsWe conducted a prospective cohort study among Thai HCPs with TB exposure from January 2013 to December 2017. Contact investigations, including baseline TB and latent tuberculosis infection (LTBI) screening and follow-up at 3 months after TB exposure, were recommended to all HCPs. The two-step tuberculin skin test (TST) was used for LTBI testing. All HCPs were followed for 2 years for TB development.ResultsOf the 342 HCPs with TB exposure included in the study, 311 (91%) participated in the contact investigations and 252 (74%) completed baseline TB and LTBI screening. Among the 210 HCPs with negative baseline TST, 45 (21%) completed the follow-up tests. The overall incidence of TB was 2.92/100 person-years. HCPs who did not complete follow-up TST had significantly higher TB incidence than those completed baseline and follow-up TST (3.55 vs. 0/100 person-years; P=0.01). No participation in the contact investigation and no chest radiograph performed at baseline were the independent factors associated with TB development among the HCPs [adjusted odds ratio (aOR) 6.69; P< 0.001 and aOR 8.85; P=0.01, respectively]. Contact with an index patient with concomitant TB at extrapulmonary sites (aOR 49.76, 10.03-246.99; P< 0.001) and with negative sputum AFB but positive sputum GeneXpert MTB/RIF (aOR 3.18, 1.35-7.50; P=0.008) were independently associated with no participation in the contact investigation.ConclusionThe findings indicate the risk of TB development among the HCPs who did not undergo or complete contact investigations and underscore the need for interventions to improve contact investigation participation and completeness.Disclosures All Authors: No reported disclosures