Clinical and epidemiological profiles of individuals with drug-resistant tuberculosis

Plasma host protein signatures correlating with Mycobacterium tuberculosis activity prior to and during antituberculosis treatment

There is a need for rapid non-sputum-based tests to identify and treat patients infected with Mycobacterium tuberculosis (Mtb). The overall objective of this study was to measure and compare the expression of a selected panel of human plasma proteins in patients with active pulmonary tuberculosis (ATB) throughout anti-TB treatment (from baseline to the end of treatment), in Mtb-infected individuals (TBI) and healthy donors (HD) to identify a putative host-protein signature useful for both TB diagnosis and treatment monitoring. A panel of seven human host proteins CLEC3B, SELL, IGFBP3, IP10, CD14, ECM1 and C1Q were measured in the plasma isolated from an HIV-negative prospective cohort of 37 ATB, 24 TBI and 23 HD. The protein signatures were assessed using a Luminex xMAP® to quantify the plasmatic levels in unstimulated blood of the different clinical group as well as the protein levels at baseline and at three timepoints during the 6-months ATB treatment, to compare the plasma protein levels between culture slow and fast converters that may contribute to monitor the TB treatment outcome. Protein signatures were defined using the CombiROC algorithm and multivariate models. The studied plasma host proteins showed different levels between the clinical groups and during the TB treatment. Six of the plasma proteins (CLEC3B, SELL, IGFBP3, IP10, CD14 and C1Q) showed significant differences in normalised median fluorescence intensities when comparing ATB vs HD or TBI groups while ECM1 revealed a significant difference between fast and slow sputum culture converters after 2 months following treatment (p = 0.006). The expression of a four-host protein markers (CLEC3B-ECM1-IP10-SELL) was significantly different between ATB from HD or TBI groups (respectively, p < 0.05). The expression of the same signature was significantly different between the slow vs the fast sputum culture converters after 2 months of treatment (p < 0.05). The results suggest a promising 4 host-plasma marker signature that would be associated with both TB diagnostic and treatment monitoring.

Relevance of QuantiFERON-TB Gold Plus and Heparin-Binding Hemagglutinin Interferon-γ Release Assays for Monitoring of Pulmonary Tuberculosis Clearance: A Multicentered Study

Background

Tuberculosis (TB) is a leading infectious cause of death. To improve treatment efficacy, quicker monitoring methods are needed. The objective of this study was to monitor the response to a heparin-binding hemagglutinin (HBHA) interferon-γ (IFN-γ) release assay (IGRA) and QuantiFERON-TB Gold Plus (QFT-P) and to analyze plasma IFN-γ levels according to sputum culture conversion and immune cell counts during treatment.

Methods

This multicentered cohort study was based in Bangladesh, Georgia, Lebanon, Madagascar, and Paraguay. Adult, non-immunocompromised patients with culture-confirmed pulmonary TB were included. Patients were followed up at baseline (T0), after two months of treatment (T1), and at the end of therapy (T2). Clinical data and blood samples were collected at each timepoint. Whole blood samples were stimulated with QFT-P antigens or recombinant methylated Mycobacterium tuberculosis HBHA (produced in Mycobacterium smegmatis; rmsHBHA). Plasma IFN-γ levels were then assessed by ELISA.

Findings

Between December 2017 and September 2020, 132 participants completed treatment, including 28 (21.2%) drug-resistant patients. rmsHBHA IFN-γ increased significantly throughout treatment (0.086 IU/ml at T0 vs. 1.03 IU/ml at T2, p < 0.001) while QFT-P IFN-γ remained constant (TB1: 0.53 IU/ml at T0 vs. 0.63 IU/ml at T2, p = 0.13). Patients with low lymphocyte percentages (<14%) or high neutrophil percentages (>79%) at baseline had significantly lower IFN-γ responses to QFT-P and rmsHBHA at T0 and T1. In a small group of slow converters (patients with positive cultures at T1; n = 16), we observed a consistent clinical pattern at baseline (high neutrophil percentages, low lymphocyte percentages and BMI, low TB1, TB2, and MIT IFN-γ responses) and low rmsHBHA IFN-γ at T1 and T2. However, the accuracy of the QFT-P and rmsHBHA IGRAs compared to culture throughout treatment was low (40 and 65% respectively). Combining both tests improved their sensitivity and accuracy (70-80%) but not their specificity (<30%).

Conclusion

We showed that QFT-P and rmsHBHA IFN-γ responses were associated with rates of sputum culture conversion. Our results support a growing body of evidence suggesting that rmsHBHA IFN-γ discriminates between the different stages of TB, from active disease to controlled infection. However, further work is needed to confirm the specificity of QFT-P and rmsHBHA IGRAs for treatment monitoring.

Association of baseline white blood cell counts with tuberculosis treatment outcome: a prospective multicentered cohort study

OBJECTIVES

Tuberculosis (TB) is the leading infectious cause of death in the world. Cheaper and more accessible TB treatment monitoring methods are needed. Here, we evaluated white blood cell (WBC) absolute counts, lymphocyte, and monocyte proportions during TB treatment, and characterized their association with treatment failure.

METHODS

This multicentered prospective cohort study was based in Bangladesh, Georgia, Lebanon, Madagascar, and Paraguay. Adult, non-immunocompromised patients with culture-confirmed pulmonary TB were included and followed up after two months of treatment and at the end of therapy. Blood counts were compared to treatment outcome using descriptive statistics, logistic regression, and Receiver Operating Characteristic (ROC) analyses.

RESULTS

Between December 2017 and August 2020, 198 participants were enrolled, and 152 completed treatment, including 28 (18.5%) drug-resistant patients. The rate of cure at the end of treatment was 90.8% (138/152). WBC absolute counts decreased, and lymphocyte proportions increased throughout treatment. In multivariate analyses, baseline high WBC counts and low lymphocyte proportions were associated with positive sputum culture results at the end of treatment (WBC > 11,450 cells/mm³: p = 0.048; lymphocytes <16.0%: p = 0.039; WBC > 11,450 cells/mm³ and lymphocytes <16.0%: p = 0.024).

CONCLUSION

High WBC counts and low lymphocyte proportions at baseline are significantly associated with the risk of TB treatment failure.

Molecular Analysis of Mycobacterium tuberculosis Isolated in the North Central Zone of Nigeria

Tuberculosis (TB) incidence in Nigeria is high, with a significant burden of TB/Human Immunodeficiency Virus (HIV). Genotyping and drug susceptibility of Mycobacterium tuberculosis Complex (MTBC) are important in order to improve the control of the disease. This study sought to determine drug susceptibility and genetic diversity of MTBC in the country. The sputum samples of 202 patients [133 (65.8%) males/69 (34.2%) females] were collected in the North Central zone of Nigeria and cultured using Lowenstein–Jensen medium. Immunochromatography for the primary identification and Drug Susceptibility Testing (DST) by proportion method, as well as IS6110 typing, regions of difference 1, 4, 9, 12, 702, and 711, and spoligotyping were carried out on the isolates. Following the DST on 202 isolates, 51 (25.2%) showed resistance to at least one drug. Multidrug resistance was observed in 29/202 (14.4%) cases. HIV positivity [37/202 (18.3%) patients] was associated with rifampicin 9/37 (24.3%) resistance (p = 0.012) as well as gender (p = 0.009). Of the 202 isolates, 150 (74.3%) were identified as the Cameroon sublineage, followed by the UgandaI, Haarlem, and West Africa 1 with 18 (8.9%), 10 (5%), and 6 (3%), respectively. The LAM10_CAM was the most prevalent genetic family [128/202 (63.4%)], with the shared international type 61 [111 (55%) isolates] the largest cluster. Gender (p = 0.038) and age (p = 0.015) had significant associations with the LAM10_CAM family but neither with HIV (p = 0.479) nor drug resistance. Rifampicin resistance in TB/HIV coinfected patient is a major concern in the study area. The Mycobacterium africanum lineage showed a marked decrease, and the need to educate females most at risk of TB/HIV coinfection is advocated.

Management of multidrug-resistant tuberculosis: main recommendations of the Brazilian guidelines

Over the years, various recommendations have been made in pursuit of controlling resistance to antituberculosis drugs, especially multidrug resistance, in Brazil. Given the importance of standardizing those recommendations, the aim of this study was to describe the main recommendations of the Brazilian guidelines, primarily those related to the treatment and follow-up of cases of tuberculosis. From August through October of 2018, a document search was conducted via the websites of the Brazilian National Ministry of Health, the Brazilian National Tuberculosis Control Program, the JBP, and the Official Gazette of the Federal Republic of Brazil. Data were collected systematically by using a protocol designed specifically for this study. Documents published between 2004 and 2018 were selected. It was possible to understand and trace the history of the measures for the control of multidrug-resistant tuberculosis in Brazil from 2004, when the first documents related to the disease were published, up to 2018, when the second edition of the Brazilian National Guidelines for the Control of Tuberculosis was published. The contents of the documents were analyzed and grouped by case definition, diagnostic criteria, treatment, use of directly observed treatment; mechanisms of social protection for patients; data tools; and organization of care. This analysis allowed us to understand the efforts towards standardizing some measures in Brazil, not only identifying advances in the alignment with international prerogatives (case definition, incorporation of diagnostic technology, and treatment regimens) but also underscoring the need for greater clarity regarding the mechanisms of social protection and the organization of the care provided via the Brazilian health care system.

GeneXpert Mycobacterium tuberculosis/rifampicin assay for molecular epidemiology of rifampicin-Resistant Mycobacterium tuberculosis in an Urban Setting of Banten province, Indonesia

Background

Tuberculosis (TB) is the fourth leading cause of death in Indonesia. In 2017, the World Health Organization (WHO) estimated that only 2% of the TB patients in Indonesia had only been tested with rapid diagnostics at the time of diagnosis, resulting in largely underdetected rifampicin-resistant TB (RR-TB). Utilization of GeneXpert Mycobacterium tuberculosis/rifampicin (MTB/RIF) assay as a point-of-care molecular assay to detect TB and RR-TB and serving its purpose in accordance with the first pillar of the WHO End-TB Strategy.

Objective

This study investigated the use of GeneXpert MTB/RIF assay to determine the molecular epidemiology of RR-TB in an urban setting of Indonesia.

Methods

All molecular epidemiological and microbiological databases were retrospectively examined from GeneXpert MTB/RIF assay results in Siloam Hospital Lippo Village. The sociodemographic characteristics and results of microbiological examinations consisting of Ziehl-Neelsen staining and GeneXpert MTB/RIF assay were analyzed.

Results

During the study period, 600 cases were registered, and GeneXpert MTB/RIF tests were done in which the tests yielded 597 (99.5%) valid results; 62.0% were male and adult of age category; of whom 29 samples (4.9%) were found to be RR-TB, 186 samples (31.2%) were RIF sensitive, and remainders were negative.

Conclusions

The results of GeneXpert MTB/RIF to be a fundamental diagnosis of RR-TB and subsequently to notify MDR-TB were satisfying and valuable in this study. This further increased and reinforced TB surveillance and national TB program to finally bring about WHO end-TB strategy one step closer in Indonesia.

Analysis of anti-tuberculosis drug resistance and sociodemographic and clinical aspects of patients admitted in a referral hospital

OBJECTIVE

To determine the occurrence of anti-tuberculosis drug resistance and its association with sociodemographic and clinical characteristics of patients in a referral hospital.

METHODS

This was a cross-sectional study based on data from patients who had mycobacterial culture identified and defined antimicrobials sensitivity profile (June 2014 to February 2016). The descriptive statistical analysis and Fisher's exact test were used to compare proportions.

RESULTS

The study included 104 patients who had positive results for Mycobacterium tuberculosis . Bacilloscopy had high positivity (93.3%). A total of 15 patients (14.4%) had resistant strains and six (5.6%) multidrug-resistant. The sociodemographic and clinical characteristics were not related with resistance.

CONCLUSION

This study contributed to further the understandings about the tuberculosis patients' profile, the study also served as a tool for development of specific public policies. Patients diagnosed with resistant tuberculosis must be under greater supervision.

Finding New Ways to Combat Multidrug-Resistant Tuberculosis

Tuberculosis (TB) is a major issue in global health and affects millions of people each year. Multidrug-resistant tuberculosis (MDR-TB) annually causes many deaths worldwide. Development of a way to diagnose and treat patients with MDR-TB can potentially reduce the incidence of the disease. The current study reviews the risk factors, pattern of progression, mechanism of resistance, and interaction between bacteria and the host immune system, which disrupts the immune response. It also targets the components of Mycobacterium tuberculosis (Mtb) and diagnosis and treatment options that could be available for clinical use in the near future. Mutations play an important role in development of MDR-TB and the selection of appropriate mutations can help to understand the type of resistance in patients to anti-TB drugs. In this way, they can be initially treated with proper and effective therapeutic choices, which can accelerate the course of treatment and improve patient health. Targeting the components and enzymes of Mtb is necessary for understanding bacterial survival and finding a way to destroy the pathogen and allow patients to recover faster and prevent the spread of disease, especially resistant strains.

Brazilian cities profile, the occurence of tuberculosis an its drug-resistant form

Tuberculosis is closely related to living conditions. This study classifies Brazilian municipalities according to the occurrence of tuberculosis (TB) and drug-resistant TB (DR-TB) cases and describes them with regard to the population's health conditions, tuberculosis control indicators, demographic and socioeconomic profile. In 2014, 327 municipalities reported DR-TB cases. Integrated regions of development or metropolitan regions accounted for 80.1% of national DR-TB cases. Municipalities with DR-TB cases had worse TB outcome indicators, but higher culture test percentages, and more inhabitants and better socioeconomic indicators. The 3,644 municipalities with TB cases, but without DR-TB cases, had the worst socioeconomic indicators among the three groups. The 1,594 municipalities without TB cases had the lowest rates of unemployment and AIDS detection and greater coverage of primary healthcare. The different profiles found in the study can sustain improved national interventions for TB and drug-resistant TB control in Brazil.

Rifampicin resistance in mycobacterium tuberculosis patients using GeneXpert at Livingstone Central Hospital for the year 2015: a cross sectional explorative study

Background

Since the recent introduction of GeneXepert for the detection of Tuberculosis (TB) drug resistance mutations in both primary resistance and acquired resistance in Zambia, little has been documented in literature on the issue of rifampicin resistance especially in the face of a high National TB burden. The study aimed to determine the prevalence of rifampicin resistance in tuberculosis patients at Livingstone Central Hospital for the year 2015.

Methods

This was a cross sectional study conducted at Livingstone Central Hospital where we reviewed 152 records (from January 1, 2015 to 31st December, 2015) involving patients who presented with clinically suspected TB or documented TB, whose samples were sent to the laboratory for GeneXpert Mycobacterium tuberculosis/rifampicin testing. Statistical evaluations used a one-sample test of proportion and Fisher’s exact test.

Results

The age of participants ranged from 8 months to 73 years old (median = 34). Of the participants with complete data on gender, 99 (66%) and 52 (34%) were males and females respectively. The TB co-infection with HIV prevalence was 98.3% (p < 0.001). Prevalence of rifampicin resistance was 5.9% and there was no statistical significant difference between being male or female (p = 0.721).

Conclusion

We were able to show from our study, evidence of rifampicin resistance at Livingstone Central Hospital. Hence, there was need for further in-depth research and appropriate interventions (i.e close follow-up and patient care for drug resistance positive patients).