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Prior studies in predominantly European (Caucasian) populations have discovered common genetic variants (single nucleotide polymorphisms, SNPs) associated with leukocyte telomere length (LTL), but whether these same variants affect LTL in non-Caucasian populations are largely unknown. We investigated whether six genetic variants previously associated with LTL (TERC (rs10936599), TERT (rs2736100), NAF1 (7675998), OBFC1 (rs9420907), ZNF208 (rs8105767), and RTEL1 (rs755017)) are correlated with telomere length (TL) in peripheral blood mononuclear cells (PBMCs) in a cohort of Africans living with and without HIV and undergoing evaluation for tuberculosis (TB). We found OBFC1 and the genetic sum score of the effect alleles across all six loci to be associated with shorter TL (adjusted for age, gender, HIV status, and smoking pack-years (p < 0.02 for both OBFC1 and the genetic sum score). In an analysis stratified by HIV status, the genetic sum score is associated with LTL in both groups with and without HIV. On the contrary, a stratified analysis according to TB status revealed that in the TB-positive subgroup, the genetic sum score is not associated with LTL, whereas the relationship remains in the TB-negative subgroup. The different impacts of HIV and TB on the association between the genetic sum score and LTL indicate different modes of modification and suggest that the results found in this cohort with HIV and TB participants may not be applied to the African general population. Future studies need to carefully consider these confounding factors.
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Infecciones por VIH/genética , Proteínas de Unión a Telómeros/genética , Telómero/genética , Tuberculosis/genética , Adulto , África , Alelos , Estudios de Cohortes , ADN Helicasas/genética , Demografía , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Leucocitos/metabolismo , Masculino , Polimorfismo de Nucleótido Simple , ARN/genética , Ribonucleoproteínas/genética , Telomerasa/genéticaRESUMEN
BACKGROUND: It is unknown whether immunosuppression influences the physiologic state of Mycobacterium tuberculosis in vivo. We evaluated the impact of host immunity by comparing M. tuberculosis and human gene transcription in sputum between human immunodeficiency virus (HIV)-infected and uninfected patients with tuberculosis. METHODS: We collected sputum specimens before treatment from Gambians and Ugandans with pulmonary tuberculosis, revealed by positive results of acid-fast bacillus smears. We quantified expression of 2179 M. tuberculosis genes and 234 human immune genes via quantitative reverse transcription-polymerase chain reaction. We summarized genes from key functional categories with significantly increased or decreased expression. RESULTS: A total of 24 of 65 patients with tuberculosis were HIV infected. M. tuberculosis DosR regulon genes were less highly expressed among HIV-infected patients with tuberculosis than among HIV-uninfected patients with tuberculosis (Gambia, P < .0001; Uganda, P = .037). In profiling of human genes from the same sputa, HIV-infected patients had 3.4-fold lower expression of IFNG (P = .005), 4.9-fold higher expression of ARG1 (P = .0006), and 3.4-fold higher expression of IL10 (P = .0002) than in HIV-uninfected patients with tuberculosis. CONCLUSIONS: M. tuberculosis in HIV-infected patients had lower expression of the DosR regulon, a critical metabolic and immunomodulatory switch induced by NO, carbon monoxide, and hypoxia. Our human data suggest that decreased DosR expression may result from alternative pathway activation of macrophages, with consequent decreased NO expression and/or by poor granuloma formation with consequent decreased hypoxic stress.
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Adaptación Fisiológica/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/microbiología , Mycobacterium tuberculosis/inmunología , Tuberculosis Pulmonar/inmunología , Adulto , Proteínas Bacterianas/genética , Proteínas de Unión al ADN , Gambia , Granuloma/genética , Granuloma/inmunología , Granuloma/microbiología , Infecciones por VIH/genética , Humanos , Hipoxia/inmunología , Hipoxia/microbiología , Macrófagos/inmunología , Macrófagos/microbiología , Mycobacterium tuberculosis/genética , Óxidos de Nitrógeno/inmunología , Proteínas Quinasas/genética , Regulón/genética , Regulón/inmunología , Esputo/microbiología , Transcripción Genética/genética , Transcripción Genética/inmunología , Tuberculosis Pulmonar/genética , Tuberculosis Pulmonar/microbiología , UgandaRESUMEN
BACKGROUND: Treatment initiation rapidly kills most drug-susceptible Mycobacterium tuberculosis, but a bacterial subpopulation tolerates prolonged drug exposure. We evaluated drug-tolerant bacilli in human sputum by comparing messenger RNA (mRNA) expression of drug-tolerant bacilli that survive the early bactericidal phase with treatment-naive bacilli. METHODS: M. tuberculosis gene expression was quantified via reverse-transcription polymerase chain reaction in serial sputa from 17 Ugandans treated for drug-susceptible pulmonary tuberculosis. RESULTS: Within 4 days, bacterial mRNA abundance declined >98%, indicating rapid killing. Thereafter, the rate of decline slowed >94%, indicating drug tolerance. After 14 days, 16S ribosomal RNA transcripts/genome declined 96%, indicating slow growth. Drug-tolerant bacilli displayed marked downregulation of genes associated with growth, metabolism, and lipid synthesis and upregulation in stress responses and key regulatory categories-including stress-associated sigma factors, transcription factors, and toxin-antitoxin genes. Drug efflux pumps were upregulated. The isoniazid stress signature was induced by initial drug exposure, then disappeared after 4 days. CONCLUSIONS: Transcriptional patterns suggest that drug-tolerant bacilli in sputum are in a slow-growing, metabolically and synthetically downregulated state. Absence of the isoniazid stress signature in drug-tolerant bacilli indicates that physiological state influences drug responsiveness in vivo. These results identify novel drug targets that should aid in development of novel shorter tuberculosis treatment regimens.
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Antituberculosos/uso terapéutico , Farmacorresistencia Bacteriana/genética , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/metabolismo , Tuberculosis Pulmonar/microbiología , Adaptación Fisiológica , Antituberculosos/farmacología , Humanos , Mycobacterium tuberculosis/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Esputo/microbiología , Transcripción Genética , Transcriptoma , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/epidemiología , Uganda/epidemiologíaRESUMEN
The World Health Organization End TB strategy aims for a 90% reduction of tuberculosis (TB) incidence by 2035. Systematic testing and treatment of latent TB infection (LTBI) among contacts of active TB patients is recommended as one of the ways to curtail TB incidence. However, there is a shortage of tools to accurately diagnose LTBI. We assessed the appropriateness of whole blood host transcriptomic markers (TM) to diagnose LTBI among household contacts of bacteriologically confirmed index cases compared to HIV negative healthy controls (HC). QuantiFERON-TB Gold Plus Interferon gamma release assay (IGRA) and reverse-transcriptase quantitative PCR were used to determine LTBI and quantify TM expression respectively. Association between TM expression and LTBI was evaluated by logistic regression modelling. A total of 100 participants, 49 TB exposed (TBEx) household contacts and 51 HC, were enrolled. Twenty-five (51%) TBEx individuals tested positive by IGRA, and were denoted as LTBI individuals, and 37 (72.5%) HC were IGRA-negative. Expression of 11 evaluated TM was significantly suppressed among LTBI compared to HC. Out of the 11 TM, ZNF296 and KLF2 expression were strongly associated with LTBI and successfully differentiated LTBI from HC. Paradoxically, 21 (49%) TBEx participants who tested IGRA negative exhibited the same pattern of suppressed TM expression as IGRA positive (LTBI-confirmed individuals). Results suggest that suppression of gene expression underlies LTBI and may be a more sensitive diagnostic biomarker than standard-of-care IGRA.
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Biomarcadores , Tuberculosis Latente , Humanos , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/sangre , Tuberculosis Latente/genética , Masculino , Femenino , Adulto , Biomarcadores/sangre , Persona de Mediana Edad , Ensayos de Liberación de Interferón gamma/métodos , Adulto Joven , Transcriptoma , Estudios de Casos y Controles , AdolescenteRESUMEN
Mycobacterium tuberculosis is an infectious pathogen that requires biosafety level-3 laboratory for handling. The risk of transmission is high to laboratory staff, and to manage the organism safely, it is necessary to construct high containment laboratory facilities at great expense. This limits the application of tuberculosis diagnostics to areas where there is insufficient capital to invest in laboratory infrastructure. In this method, we describe a process of inactivating sputum samples by either heat or guanidine thiocyanate (GTC) that renders them safe without affecting the quantification of viable bacteria. This method eliminates the need for level 3 containment laboratory for the tuberculosis molecular bacterial load assay (TB-MBLA) and is applicable in low- and middle-income countries.
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Contención de Riesgos Biológicos , Mycobacterium tuberculosis , Esputo , Tiocianatos , Mycobacterium tuberculosis/aislamiento & purificación , Humanos , Contención de Riesgos Biológicos/métodos , Esputo/microbiología , Carga Bacteriana/métodos , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Tuberculosis/prevención & control , Guanidinas , Calor , Viabilidad MicrobianaRESUMEN
The diagnosis and monitoring of tuberculosis treatment is difficult as many patients are unable to produce sputum. This means that many patients are treated on the basis of clinical findings and consequently some will be exposed to anti-tuberculosis drugs unnecessarily. Moreover, for those appropriately on treatment and unable to produce a sputum sample, it will be impossible to monitor the response to treatment. We have shown that stool is a potential alternative sample type for diagnosis of tuberculosis. Currently, available protocols like the Xpert MTB/RIF use DNA as a target to detect Mycobacterium tuberculosis in stool but DNA survives long after the organism is dead so it is not certain whether a positive test is from an old or a partially treated infection. The TB MBLA only detects live organisms and thus, can be used to follow the response to treatment. In this chapter, we describe a protocol for TB-MBLA, an RNA-based assay, and apply it to quantify TB bacteria in stool.
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Carga Bacteriana , Heces , Mycobacterium tuberculosis , Tuberculosis , Heces/microbiología , Mycobacterium tuberculosis/aislamiento & purificación , Mycobacterium tuberculosis/genética , Humanos , Carga Bacteriana/métodos , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Tuberculosis/tratamiento farmacológico , Antituberculosos/uso terapéutico , Antituberculosos/farmacología , ADN Bacteriano/genética , Esputo/microbiologíaRESUMEN
Background: Preserved ratio impaired spirometry (PRISm), defined as a normal ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (≥0.70) with low FEV1 (<80% predicted), has been associated with increased mortality in the general population. Female sex has been associated with increased odds of PRISm in people without HIV. People with HIV (PWH) are at increased risk for lung function abnormalities, but whether HIV modifies the effect of sex on PRISm development is largely unknown. Methods: Adults with and without HIV underwent baseline followed by serial spirometry after completing therapy for pneumonia, predominantly tuberculosis (TB), in Kampala, Uganda. Using generalized estimating equations adjusted for age, body mass index, smoking, biomass fuel exposure, HIV, and TB status, we compared individuals with PRISm with those with normal spirometry. These models were stratified by HIV status. Results: Of 339 baseline participants, 153 (45%) were women; 129 (38%) had HIV, of whom 53% were women. Overall, 105/339 participants (31%) had PRISm at baseline. HIV was associated with lower odds of PRISm (adjusted odds ratio [aOR], 0.38; 95% CI, 0.21-0.68; P = .001). Female sex trended toward increased odds of PRISm among all participants (aOR, 1.65; 95% CI, 0.99-2.75; P = .052). The association between female sex and PRISm tended to be stronger among PWH (aOR, 3.16; 95% CI, 1.14-8.76; P = .03) than among those without HIV (aOR, 1.34; 95% CI, 0.73-2.45; P = .34); this study was underpowered to detect an HIV-sex interaction of this magnitude (P = .30). Conclusions: Among Ugandan adults who recovered from pneumonia, female sex was associated with increased odds and HIV with decreased odds of PRISm, suggesting independent sex and HIV effects on PRISm pathogenesis.
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BACKGROUND: In 2018, the tuberculosis molecular bacterial load assay (TB-MBLA), a ribosomal RNA-based test, was acknowledged by WHO as a molecular assay that could replace smear microscopy and culture for monitoring tuberculosis treatment response. In this study, we evaluated the accuracy of TB-MBLA for diagnosis and monitoring of treatment response in comparison with standard-of-care tests. METHODS: For this longitudinal prospective study, patients aged 18 years or older with presumptive tuberculosis (coughing for at least 2 weeks, night sweats, and weight loss) were enrolled at China-Uganda Friendship Hospital Naguru (Kampala, Uganda). Participants were evaluated for tuberculosis by TB-MBLA in comparison with Xpert MTB/RIF Ultra (Xpert-Ultra) and smear microscopy, with Mycobacteria Growth Indicator Tube (MGIT) culture as a reference test. Participants who were positive on Xpert-Ultra were enrolled on a standard 6-month anti-tuberculosis regimen, and monitored for treatment response at weeks 2, 8, 17, and 26 after initiation of treatment and then 3 months after treatment. FINDINGS: Between Nov 15, 2019, and June 15, 2022, 210 participants (median age 35 years [IQR 27-44]) were enrolled. 135 (64%) participants were male and 72 (34%) were HIV positive. The pretreatment diagnostic sensitivities of TB-MBLA and Xpert-Ultra were similar (both 99% [95% CI 95-100]) but the specificity was higher for TB-MBLA (90% [83-96]) than for Xpert-Ultra (78% [68-86]). Ten participants were Xpert-Ultra trace positive, eight (80%) of whom were negative by TB-MBLA and MGIT culture. Smear microscopy had lower diagnostic sensitivity (75% [65-83]) but higher specificity (98% [93-100]) than TB-MBLA and Xpert-Ultra. Among participants who were smear microscopy negative, the sensitivity of TB-MBLA was 96% (95 CI 80-100) and was 100% (95% CI 86-100) in those who were HIV positive. 129 (61%) participants were identified as tuberculosis positive by Xpert-Ultra and these individuals were enrolled in the treatment group and monitored for treatment response. According to TB-MBLA, 19 of these patients cleared bacillary load to zero by week 2 of treatment and remained negative throughout the 6-month treatment follow-up. Positivity for tuberculosis decreased with treatment as measured by all tests, but the rate was slower with Xpert-Ultra. Consequently, 31 (33%) of 95 participants were still Xpert-Ultra positive at the end of treatment but were clinically well and negative on TB-MBLA and culture at 6 months of treatment. Two patients were still Xpert-Ultra positive with a further 3 months of post-treatment follow-up. The rate of conversion to negative of the DNA-based Xpert-Ultra was 3·3-times slower than that of the rRNA-based TB-MBLA. Consequently for the same patient, it would take 13 weeks and 52 weeks to reach complete tuberculosis negativity by TB-MBLA and Xpert-Ultra, respectively. Participants who were positive on smear microscopy at 8 weeks, who received an extra month of intensive treatment, had a similar TB-MBLA-measured bacillary load at 8 weeks to those who were smear microscopy negative. INTERPRETATION: TB-MBLA has a similar performance to Xpert-Ultra for pretreatment diagnosis of tuberculosis, but is more accurate at detecting and characterising the response to treatment than Xpert-Ultra and standard-of-care smear microscopy. FUNDING: European and Developing Countries Clinical Trials Partnership, Makerere University Research and Innovation Fund, US National Institutes of Health.
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Antibióticos Antituberculosos , Seropositividad para VIH , Mycobacterium tuberculosis , Tuberculosis Pulmonar , Tuberculosis , Estados Unidos , Humanos , Masculino , Adulto , Femenino , Antibióticos Antituberculosos/uso terapéutico , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/microbiología , Rifampin/farmacología , Rifampin/uso terapéutico , Uganda , Estudios Prospectivos , Carga Bacteriana , Microscopía , Sensibilidad y Especificidad , Mycobacterium tuberculosis/genética , Tuberculosis/tratamiento farmacológico , Seropositividad para VIH/tratamiento farmacológicoRESUMEN
BACKGROUND: Stool is a potential sample for diagnosing Mycobacterium tuberculosis (Mtb) in patients with difficulty in expectorating. However, high mycobacterial culture contamination rates and Xpert MTB/RIF Ultra test error rates on stool samples have limited its use. OMNIgene SPUTUM (OM-S) is a sample transport reagent with characteristics of sputum decontamination while maintaining viable Mtb. We evaluated the impact of OM-S on Mtb diagnostic yield from stool using smear microscopy, Xpert MTB/RIF Ultra, and culture among presumptive TB patients. METHODS: Paired stool and expectorated sputum samples were collected from consecutive Ugandan adults undergoing diagnostic evaluation for pulmonary TB between June 2018 and June 2019. Stool was divided into 2 portions: one was homogenized in OM-S (OM-S stool) and the other in PBS (PBS stool) as control. Both sputum and processed stool were tested for Mtb using concentrated smear fluorescence microscopy (CFM), Xpert MTB/RIF Ultra (Xpert) and Mycobacteria Growth Indicator Tube (MGIT) culture. Sensitivity, specificity, and predictive values for each test were calculated against sputum MGIT culture as the reference standard. RESULTS: Of the 200 participants, 120 (60%) were male, 73 (37%) were HIV positive (median CD4 120 cells/uL (IQR 43-297)) and 128 (64%) had confirmed pulmonary TB by sputum MGIT culture. Seven (4%) OM-S stool Xpert samples reported errors while 47 (25%) and 103 (61%) were contaminated on OM-S stool MGIT and PBS stool MGIT, respectively. OM-S stool MGIT was able to accurately diagnose 56 of the contaminated PBS stool MGIT samples compared to only 5 of the contaminated OM-S stool MGIT samples diagnosed by PBS stool MGIT. Sensitivity (95% Confidence Interval, CI) 89% (83-94) for OM-S stool Xpert was higher compared to that of OM-S stool MGIT 60% (51-69) and PBS stool MGIT 42% (32-52). Specificity (95%CI) 91% (82-97) was also higher for OM-S stool Xpert compared to OM-S stool MGIT 64% (51-75) and PBS stool MGIT 26% (16-38). CONCLUSION: Stool processed with OM-S showed potential to improve Mtb diagnostic yield and reduce rates of indeterminate results when tested on Xpert and MGIT culture. The method may thus be of value in Mtb detection among patients with difficulty to expectorate.
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Mycobacterium tuberculosis , Tuberculosis Pulmonar , Humanos , Masculino , Adulto , Femenino , Mycobacterium tuberculosis/genética , Uganda , Esputo/microbiología , Sensibilidad y Especificidad , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/microbiología , Microscopía FluorescenteRESUMEN
BACKGROUND: Respiratory tract microbiota has been described as the gatekeeper for respiratory health. We aimed to assess the impact of standard-of-care and experimental anti-tuberculosis treatment regimens on the respiratory microbiome and implications for treatment outcomes. METHODS: In this retrospective study, we analysed the sputum microbiome of participants with tuberculosis treated with six experimental regimens versus standard-of-care who were part of the HIGHRIF study 2 (NCT00760149) and PanACEA MAMS-TB (NCT01785186) clinical trials across a 3-month treatment follow-up period. Samples were from participants in Mbeya, Kilimanjaro, Bagamoyo, and Dar es Salaam, Tanzania. Experimental regimens were composed of different combinations of rifampicin (R), isoniazid (H), pyrazinamide (Z), ethambutol (E), moxifloxacin (M), and a new drug, SQ109 (Q). Reverse transcription was used to create complementary DNA for each participant's total sputum RNA and the V3-V4 region of the 16S rRNA gene was sequenced using the Illumina metagenomic technique. Qiime was used to analyse the amplicon sequence variants and estimate alpha diversity. Descriptive statistics were applied to assess differences in alpha diversity pre-treatment and post-treatment initiation and the effect of each treatment regimen. FINDINGS: Sequence data were obtained from 397 pre-treatment and post-treatment samples taken between Sept 26, 2008, and June 30, 2015, across seven treatment regimens. Pre-treatment microbiome (206 genera) was dominated by Firmicutes (2860 [44%] of 6500 amplicon sequence variants [ASVs]) at the phylum level and Streptococcus (2340 [36%] ASVs) at the genus level. Two regimens had a significant depressing effect on the microbiome after 2 weeks of treatment, HR20mg/kgZM (Shannon diversity index p=0·0041) and HR35mg/kgZE (p=0·027). Gram-negative bacteria were the most sensitive to bactericidal activity of treatment with the highest number of species suppressed being under the moxifloxacin regimen. By week 12 after treatment initiation, microbiomes had recovered to pre-treatment level except for the HR35mg/kgZE regimen and for genus Mycobacterium, which did not show recovery across all regimens. Tuberculosis culture conversion to negative by week 8 of treatment was associated with clearance of genus Neisseria, with a 98% reduction of the pre-treatment level. INTERPRETATION: HR20mg/kgZM was effective against tuberculosis without limiting microbiome recovery, which implies a shorter efficacious anti-tuberculosis regimen with improved treatment outcomes might be achieved without harming the commensal microbiota. FUNDING: European and Developing Countries Clinical Trials Partnership and German Ministry of Education and Research.
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Microbiota , Tuberculosis Pulmonar , Tuberculosis , Humanos , Antituberculosos/farmacología , Quimioterapia Combinada , Moxifloxacino/farmacología , Estudios Retrospectivos , ARN Ribosómico 16S , Esputo/microbiología , Tanzanía , Tuberculosis/tratamiento farmacológico , Tuberculosis Pulmonar/tratamiento farmacológico , Ensayos Clínicos como AsuntoRESUMEN
OBJECTIVES: Spirometric abnormalities are frequent, and obstructive lung disease (OLD) is a common comorbidity among people with HIV (PWH). HIV increases the risk of many comorbidities to a greater degree in women than in men. Few studies have evaluated whether sex modifies the HIV-associated risk of OLD. DESIGN AND METHODS: To evaluate the associations between sex and HIV with abnormal lung function, women and men with and without HIV underwent spirometric testing after completing therapy for pneumonia, including tuberculosis (TB), in Kampala, Uganda. OLD was defined as a postbronchodilator forced expiratory volume in the first second to forced vital capacity (FEV 1 /FVC) ratio less than 0.70. Associations between sex, HIV, and lung function were evaluated using multivariable regression models including sex-by-HIV interaction terms after adjusting for age, BMI, smoking status, and TB status. RESULTS: Among 348 participants, 147 (42%) were women and 135 (39%) were HIV-positive. Sixteen (11%) women and 23 men (11%) had OLD. The HIV-sex interaction was significant for obstructive lung disease ( P â=â0.04). In the adjusted stratified analysis, women with HIV had 3.44 (95% CI 1.11-12.0; P â=â0.04) increased odds of having OLD compared with men with HIV. Women without HIV did not have increased odds of having OLD compared with men without HIV. CONCLUSION: HIV appears to increase the risk of OLD to a greater degree in women than in men in an urban Ugandan setting. The mechanistic explanation for this interaction by sex remains unclear and warrants further study.
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Infecciones por VIH , Enfermedades Pulmonares Obstructivas , Factores Sexuales , Femenino , Humanos , Masculino , Volumen Espiratorio Forzado , Infecciones por VIH/complicaciones , Pulmón , Enfermedades Pulmonares Obstructivas/complicaciones , Enfermedades Pulmonares Obstructivas/epidemiología , Espirometría , Uganda/epidemiología , Capacidad VitalRESUMEN
Objective: The objective of the study was to determine the diagnostic performance of the GenoQuick MTB test on heated sputum against the conventional Lowenstein-Jensen Mycobacterium tuberculosis culture as the reference method for tuberculosis diagnosis. Introduction: Fast, reliable, and easy-to-use tests for tuberculosis diagnosis are essential to achieving the Sustainable Development Goal of diagnosing and treating 90% of tuberculosis patients by 2030. We evaluated the diagnostic performance of the GenoQuick MTB, a polymerase chain reaction-lateral flow test, in Uganda, a resource-constrained, high tuberculosis- and HIV-burden setting. Methods: Fresh sputum samples from presumptive tuberculosis patients at Mulago Hospital were tested for M. tuberculosis using smear microscopy, GenoQuick MTB test, and Lowenstein-Jensen culture. For the GenoQuick MTB test, mycobacterial DNA was extracted by heating sputum at 95°C for 30 min while DNA amplification and detection were done following the manufacturer's protocol (Hain Lifescience, Nehren, Germany). Sensitivity, specificity, and kappa agreements were calculated against Lowenstein-Jensen M. tuberculosis culture as a reference test using STATA V12. Results: Of the 86 tested samples, 30.2% had culture-confirmed pulmonary tuberculosis. Overall, sensitivity was higher for GenoQuick MTB (81%, 95% confidence interval: 60%-93%) than for smear microscopy (69%, 95% confidence interval: 48%-86%). Among people living with HIV, sensitivity was identical for GenoQuick MTB and smear tests (75%, 95% confidence interval: 42%-95%). Contrastingly, smear had a higher overall specificity (98%, 95% confidence interval: 91%-100%) than for GenoQuick MTB (92%, 95% confidence interval: 81%-97%). A similar trend of specificity was observed among the people living with HIV for smear microscopy (100%, 95% CI: 87%-100%) and for GenoQuick MTB (96%, 95% confidence interval: 81%-100%). Conclusion: The GenoQuick MTB test could be a potential tuberculosis diagnostic test given its higher sensitivity. Evaluation of this test in larger studies is recommended.
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The objective of this prospective observational study carried out at China-Uganda Friendship Hospital-Naguru in Kampala, Uganda, was to determine the performance of GeneXpert MTB/RIF Ultra (Xpert Ultra) molecular testing on saliva for active tuberculosis (TB) disease among consecutive adults undergoing TB diagnostic evaluation who were Xpert Ultra positive on sputum. We calculated sensitivity to determine TB diagnostic performance in comparison to a composite reference standard of Mycobacterium tuberculosis liquid and solid cultures on two spot sputum specimens. Xpert Ultra on a single saliva sample had a sensitivity of 90% (95% confidence interval [CI], 81 to 95%) relative to the composite sputum culture-based reference standard, similar to the composite sensitivity of 87% (95% CI, 77 to 94%) for fluorescence microscopy (FM) for acid-fast bacilli on two sputum smears. The sensitivity of salivary Xpert Ultra was 24% lower (95% CI for difference, 2 to 48%; P = 0.003) among persons living with HIV (71%; 95% CI, 44 to 90%) than among persons living without HIV (95%; 95% CI, 86 to 99%) and 46% higher (95% CI, 14 to 77%; P < 0.0001) among FM-positive (96%; 95% CI, 87 to 99%) than among FM-negative (50%; 95% CI, 19 to 81%) patients. The semiquantitative Xpert Ultra grade was systematically higher in sputum than in a paired saliva sample from the same patient. In conclusion, molecular testing of saliva for active TB diagnosis was feasible and almost as sensitive as molecular testing of sputum in a high TB burden setting. IMPORTANCE Tuberculosis is among the leading causes of morbidity and mortality worldwide, in large part because >3 million people go undiagnosed and untreated each year. Sputum has been the mainstay for TB diagnosis for over a century but can be difficult for patients to produce. In addition, the vigorous coughing required during sputum collection can lead to infection of nearby individuals and health workers. In this case-only study, applying the ultra-sensitive GeneXpert MTB/RIF Ultra molecular diagnostic assay to saliva detected 90% of culture-confirmed TB cases among 81 adults who were undergoing TB evaluation at the outpatient department of a general hospital in Uganda and tested sputum GeneXpert MTB/RIF Ultra positive. These results suggest that saliva may be a feasible and sensitive alternative to sputum for TB diagnosis, thereby meeting two key metrics proposed by the World Health Organization in its target performance profile for a nonsputum test for TB.
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Infecciones por VIH , Mycobacterium tuberculosis , Tuberculosis Ganglionar , Adulto , Humanos , Rifampin , Saliva , Uganda , Estudios de Factibilidad , Sensibilidad y Especificidad , Mycobacterium tuberculosis/genéticaRESUMEN
Not all patients produce sputum, yet most available TB tests use sputum. We investigated the utility of a novel RNA-based quantitative test, the tuberculosis molecular bacterial load assay (TB-MBLA), for the detection and quantification of Mycobacterium tuberculosis in stool. Stools from 100 adult individuals were treated with OMNIgene-sputum reagent and tested using Xpert MTB/RIF ultra (Xpert ultra), auramine O smear microscopy (smear), mycobacterial growth indicator tube (MGIT), and Lowenstein-Jensen (LJ) cultures. The remaining portions were frozen at -20°C and later tested by TB-MBLA. MGIT sputum culture was used as a TB confirmatory test and reference for stool tests. Sixty-one of 100 participants were already confirmed TB positive by MGIT sputum culture, 20 (33%) of whom were HIV coinfected. TB-MBLA detected M. tuberculosis in 57/100 stool samples, including 49 already confirmed for TB. The mean bacterial load measured by stool TB-MBLA was 5.67 ± 1.7 log10 estimated CFU (eCFU) per mL in HIV-coinfected participants, which was higher than the 4.83 ± 1.59 log10 eCFU per mL among the HIV-negative participants (P = 0.04). The sensitivities (95% confidence intervals [CI]) of stool assays were 80% (68 to 89) and 90% (79 to 98) for TB-MBLA and Xpert ultra, which were both higher than the 44% (32 to 58), 64% (51 to 76), and 62% (45 to 77) for smear, MGIT, and Lowenstein-Jensen (LJ) stool cultures, respectively. The specificity (95% CI) of stool assays was highest for smear, at 97% (87 to 100), followed by Xpert ultra at 91% (76 to 98), TB-MBLA at 79% (63 to 90), LJ at 80% (64 to 91), and MGIT at 62% (45 to 77). Twenty-six percent of MGIT and 21% of LJ stool cultures were indeterminate due to contamination. Detection and quantification of viable M. tuberculosis bacilli in stool raises its utility as an alternative to sputum as a sample type for TB diagnosis. IMPORTANCE This paper highlights the value of stool as a sample type for diagnosis of tuberculosis. While other studies have used DNA-based assays like the Xpert MTB/RIF and culture to detect Mycobacterium tuberculosis in stool, this is the first study that has applied TB-MBLA, an RNA-based assay, to quantify TB bacteria in stool. The high microbial density and diversity in stool compromises the specificity and sensitivity of culture-based tests due to overgrowth of non-M. tuberculosis flora. Consequently, TB-MBLA becomes the most sensitive and specific test for the detection and quantification of viable TB bacteria in stool. Most crucially, this study raises the possibility of a nonsputum alternative sample type for diagnosis of TB among people who have difficulty in producing sputum.
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Carga Bacteriana , Heces/microbiología , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/genética , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Tuberculosis/terapia , Adulto , Estudios Transversales , Femenino , Infecciones por VIH , Humanos , Masculino , Microscopía , Sensibilidad y Especificidad , EsputoRESUMEN
There is a critical need for improved pharmacodynamic markers for use in human tuberculosis (TB) drug trials. Pharmacodynamic monitoring in TB has conventionally used culture or molecular methods to enumerate the burden of Mycobacterium tuberculosis organisms in sputum. A recently proposed assay called the rRNA synthesis (RS) ratio measures a fundamentally novel property, how drugs impact ongoing bacterial rRNA synthesis. Here, we evaluated RS ratio as a potential pharmacodynamic monitoring tool by testing pretreatment sputa from 38 Ugandan adults with drug-susceptible pulmonary TB. We quantified the RS ratio in paired pretreatment sputa and evaluated the relationship between the RS ratio and microbiologic and molecular markers of M. tuberculosis burden. We found that the RS ratio was highly repeatable and reproducible in sputum samples. The RS ratio was independent of M. tuberculosis burden, confirming that it measures a distinct new property. In contrast, markers of M. tuberculosis burden were strongly associated with each other. These results indicate that the RS ratio is repeatable and reproducible and provides a distinct type of information from markers of M. tuberculosis burden. IMPORTANCE This study takes a major next step toward practical application of a novel pharmacodynamic marker that we believe will have transformative implications for tuberculosis. This article follows our recent report in Nature Communications that an assay called the rRNA synthesis (RS) ratio indicates the treatment-shortening of drugs and regimens. Distinct from traditional measures of bacterial burden, the RS ratio measures a fundamentally novel property, how drugs impact ongoing bacterial rRNA synthesis.
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Mycobacterium tuberculosis/metabolismo , ARN Bacteriano/genética , ARN Ribosómico/genética , Esputo/microbiología , Tuberculosis Pulmonar/microbiología , Adulto , Biomarcadores/metabolismo , Femenino , Humanos , Masculino , Mycobacterium tuberculosis/genética , ARN Bacteriano/metabolismo , ARN Ribosómico/metabolismo , Esputo/química , Tuberculosis Pulmonar/genética , Tuberculosis Pulmonar/metabolismoRESUMEN
There is urgent need for new drug regimens that more rapidly cure tuberculosis (TB). Existing TB drugs and regimens vary in treatment-shortening activity, but the molecular basis of these differences is unclear, and no existing assay directly quantifies the ability of a drug or regimen to shorten treatment. Here, we show that drugs historically classified as sterilizing and non-sterilizing have distinct impacts on a fundamental aspect of Mycobacterium tuberculosis physiology: ribosomal RNA (rRNA) synthesis. In culture, in mice, and in human studies, measurement of precursor rRNA reveals that sterilizing drugs and highly effective drug regimens profoundly suppress M. tuberculosis rRNA synthesis, whereas non-sterilizing drugs and weaker regimens do not. The rRNA synthesis ratio provides a readout of drug effect that is orthogonal to traditional measures of bacterial burden. We propose that this metric of drug activity may accelerate the development of shorter TB regimens.
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Antituberculosos/administración & dosificación , Mycobacterium tuberculosis/efectos de los fármacos , Precursores del ARN/metabolismo , ARN Ribosómico/metabolismo , Tuberculosis/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones Endogámicos BALB C , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/fisiología , Precursores del ARN/genética , ARN Bacteriano/genética , ARN Bacteriano/metabolismo , ARN Ribosómico/genética , Resultado del Tratamiento , Tuberculosis/diagnóstico , Tuberculosis/microbiologíaRESUMEN
Pneumonia is common and frequently fatal in HIV-infected patients, due to rampant, systemic inflammation and failure to control microbial infection. While airway microbiota composition is related to local inflammatory response, gut microbiota has been shown to correlate with the degree of peripheral immune activation (IL6 and IP10 expression) in HIV-infected patients. We thus hypothesized that both airway and gut microbiota are perturbed in HIV-infected pneumonia patients, that the gut microbiota is related to peripheral CD4+ cell counts, and that its associated products differentially program immune cell populations necessary for controlling microbial infection in CD4-high and CD4-low patients. To assess these relationships, paired bronchoalveolar lavage and stool microbiota (bacterial and fungal) from a large cohort of Ugandan, HIV-infected patients with pneumonia were examined, and in vitro tests of the effect of gut microbiome products on macrophage effector phenotypes performed. While lower airway microbiota stratified into three compositionally distinct microbiota as previously described, these were not related to peripheral CD4 cell count. In contrast, variation in gut microbiota composition significantly related to CD4 cell count, lung microbiota composition, and patient mortality. Compared with patients with high CD4+ cell counts, those with low counts possessed more compositionally similar airway and gut microbiota, evidence of microbial translocation, and their associated gut microbiome products reduced macrophage activation and IL-10 expression and increased IL-1ß expression in vitro. These findings suggest that the gut microbiome is related to CD4 status and plays a key role in modulating macrophage function, critical to microbial control in HIV-infected patients with pneumonia.
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Bacterias/clasificación , Infecciones por VIH/microbiología , Pulmón/microbiología , Macrófagos/inmunología , Microbiota , Neumonía/inmunología , Bacterias/genética , Bacterias/aislamiento & purificación , Líquido del Lavado Bronquioalveolar/microbiología , Recuento de Linfocito CD4 , Quimiocina CXCL10/metabolismo , Estudios de Cohortes , ADN Bacteriano/genética , ADN Ribosómico , Heces/microbiología , Infecciones por VIH/inmunología , Humanos , Interleucina-6/metabolismo , Pulmón/inmunología , Neumonía/microbiología , Neumonía/terapia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN/métodos , UgandaRESUMEN
INTRODUCTION: Pneumonia is an important cause of morbidity and mortality in persons living with human immunodeficiency virus (HIV) infection. How immune activation differs among HIV-infected and HIV-uninfected adults with pneumonia is unknown. METHODS: The Inflammation, Aging, Microbes, and Obstructive Lung Disease (I AM OLD) Cohort is a prospective cohort of adults with pneumonia in Uganda. In this cross-sectional analysis, plasma was collected at pneumonia presentation to measure the following 12 biomarkers: interleukin 6 (IL-6), soluble tumor necrosis factor receptors 1 and 2 (sTNFR-1 and sTNFR-2), high sensitivity C-reactive protein (hsCRP), fibrinogen, D-dimer, soluble CD27 (sCD27), interferon gamma-inducible protein 10 (IP-10), soluble CD14 (sCD14), soluble CD163 (sCD163), hyaluronan, and intestinal fatty acid binding protein. We asked whether biomarker levels differed between HIV-infected and HIV-uninfected participants, and whether higher levels of these biomarkers were associated with mortality. RESULTS: One hundred seventy-three participants were enrolled. Fifty-three percent were HIV-infected. Eight plasma biomarkers-sTNFR-1, sTNFR-2, hsCRP, D-dimer, sCD27, IP-10, sCD14, and hyaluronan-were higher among participants with HIV infection, after adjustment for pneumonia severity. Higher levels of 8 biomarkers-IL-6, sTNFR-1, sTNFR-2, hsCRP, IP-10, sCD14, sCD163, and hyaluronan-were associated with increased 2-month mortality. CONCLUSIONS: As in other clinical contexts, HIV infection is associated with a greater degree of immune activation among Ugandan adults with pneumonia. Some of these are also associated with short-term mortality. Further study is needed to explore whether these biomarkers might predict poor long-term outcomes-such as the development of obstructive lung disease-in patients with HIV who have recovered from pneumonia.
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Infecciones por VIH/inmunología , Neumonía/metabolismo , Adulto , Antígenos CD/análisis , Antígenos CD/sangre , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Estudios de Cohortes , Estudios Transversales , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Infecciones por VIH/complicaciones , Infecciones por VIH/virología , Humanos , Ácido Hialurónico/análisis , Ácido Hialurónico/sangre , Inflamación/inmunología , Interleucina-6/análisis , Interleucina-6/sangre , Receptores de Lipopolisacáridos/sangre , Masculino , Persona de Mediana Edad , Monocitos/inmunología , Neumonía/complicaciones , Estudios Prospectivos , Receptores del Factor de Necrosis Tumoral/análisis , Receptores del Factor de Necrosis Tumoral/sangre , Uganda/epidemiologíaRESUMEN
INTRODUCTION: Lower respiratory tract infections (LRTIs) are a leading cause of mortality in sub-Saharan Africa. Triaging identifies patients at high risk of death, but laboratory tests proposed for use in severity-of-illness scores are not readily available, limiting their clinical use. Our objective was to determine whether baseline characteristics in hospitalized participants with LRTI predicted increased risk of death. METHODS: This was a secondary analysis from the Mulago Inpatient Non-invasive Diagnosis-International HIV-associated Opportunistic Pneumonias (MIND-IHOP) cohort of adults hospitalized with LRTI who underwent standardized investigations and treatment. The primary outcome was all-cause mortality at 2 months. Predictors of mortality were determined using multiple logistic regression. RESULTS: Of 1887 hospitalized participants with LRTI, 372 (19.7%) died. The median participant age was 34.3 years (interquartile range, 28.0-43.3 years), 978 (51.8%) were men, and 1192 (63.2%) were HIV-positive with median CD4 counts of 81 cells/µL (interquartile range, 21-226 cells/µL). Seven hundred eleven (37.7%) participants had a microbiologically confirmed diagnosis. Temperature <35.5°C [adjusted odds ratio (aOR) = 1.77, 95% confidence intervals (CI): 1.20 to 2.60; P = 0.004], heart rate >120/min (aOR = 1.82, 95% CI: 1.37 to 2.43; P < 0.0001), oxygen saturation <90% (aOR = 2.74, 95% CI: 1.97 to 3.81; P < 0.0001), being bed-bound (aOR = 1.88, 95% CI: 1.47 to 2.41; P < 0.0001), and being HIV-positive (aOR = 1.49, 95% CI: 1.14 to 1.94; P = 0.003) were independently associated with mortality at 2 months. CONCLUSIONS: Having temperature <35.5°C, heart rate >120/min, hypoxia, being HIV-positive, and bed-bound independently predicts mortality in participants hospitalized with LRTI. These readily available characteristics could be used to triage patients with LRTI in low-income settings. Providing adequate oxygen, adequate intravenous fluids, and early antiretroviral therapy (in people living with HIV/AIDS) may be life-saving in hospitalized patients with LRTI.
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Técnicas de Apoyo para la Decisión , Infecciones del Sistema Respiratorio/mortalidad , Infecciones del Sistema Respiratorio/patología , Infecciones Oportunistas Relacionadas con el SIDA/mortalidad , Adulto , África del Sur del Sahara/epidemiología , Femenino , Hospitalización , Humanos , Masculino , Pronóstico , Infecciones del Sistema Respiratorio/diagnóstico , Análisis de SupervivenciaRESUMEN
BACKGROUND: HIV infection and opportunistic infections cause oxidative stress (OS), which is associated with tissue damage. Anti-retroviral therapy (ART) is used to treat HIV and decrease the risk of opportunistic infections, but it is unclear whether ART reduces OS. Association of ART with OS was investigated. METHODS: We stratified a convenience sample of frozen serum or plasma from HIV-infected, ART-naïve (n=21); HIV-infected, ART-treated (n=14); HIV and PTB co-infected, ART-naïve (n=21); HIV and PTB co-infected, ART-treated (n=25) patients. Controls (n=21) were HIV-negative adults without TB symptoms. Concentration of OS markers namely: transaminases (ALT and AST), gamma glutamyl transpeptidase (GGT), albumin, total protein, malondialdehyde (MDA), vitamin C, and total anti-oxidant status (TAS) were determined. RESULTS: AST (p<0.001), GGT (p<0.001), total protein (p=0.001) and MDA (p<0.001) were higher in HIV patients compared to controls. Vitamin C (P<0.0001) and albumin (p<0.01) were lower in HIV-patients relative to controls. ART was only associated with higher albumin (p=0.001), higher GGT (p=0.02) and lower vitamin C (p=0.009). HIV and PTB co-infection was only significantly associated with higher GGT (p=0.01) and AST (p=0.03). CONCLUSION: We identified severe OS among HIV-patients. ART was associated with both increased and reduced markers of OS hence suggesting that ART may not attenuate OS.