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1.
Nat Commun ; 15(1): 3947, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38729951

ABSTRACT

Gram-negative bacteria (GNB) are a major cause of neonatal sepsis in low- and middle-income countries (LMICs). Although the World Health Organization (WHO) reports that over 80% of these sepsis deaths could be prevented through improved treatment, the efficacy of the currently recommended first- and second-line treatment regimens for this condition is increasingly affected by high rates of drug resistance. Here we assess three well known antibiotics, fosfomycin, flomoxef and amikacin, in combination as potential antibiotic treatment regimens by investigating the drug resistance and genetic profiles of commonly isolated GNB causing neonatal sepsis in LMICs. The five most prevalent bacterial isolates in the NeoOBS study (NCT03721302) are Klebsiella pneumoniae, Acinetobacter baumannii, E. coli, Serratia marcescens and Enterobacter cloacae complex. Among these isolates, high levels of ESBL and carbapenemase encoding genes are detected along with resistance to ampicillin, gentamicin and cefotaxime, the current WHO recommended empiric regimens. The three new combinations show excellent in vitro activity against ESBL-producing K. pneumoniae and E. coli isolates. Our data should further inform and support the clinical evaluation of these three antibiotic combinations for the treatment of neonatal sepsis in areas with high rates of multidrug-resistant Gram-negative bacteria.


Subject(s)
Acinetobacter baumannii , Anti-Bacterial Agents , Gram-Negative Bacteria , Gram-Negative Bacterial Infections , Klebsiella pneumoniae , Microbial Sensitivity Tests , Neonatal Sepsis , Humans , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology , Neonatal Sepsis/microbiology , Neonatal Sepsis/drug therapy , Infant, Newborn , Gram-Negative Bacteria/drug effects , Gram-Negative Bacteria/genetics , Gram-Negative Bacteria/isolation & purification , Gram-Negative Bacterial Infections/drug therapy , Gram-Negative Bacterial Infections/microbiology , Acinetobacter baumannii/drug effects , Acinetobacter baumannii/isolation & purification , Acinetobacter baumannii/genetics , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/genetics , Amikacin/pharmacology , Amikacin/therapeutic use , Fosfomycin/pharmacology , Fosfomycin/therapeutic use , beta-Lactamases/genetics , beta-Lactamases/metabolism , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli/isolation & purification , Developing Countries , Drug Resistance, Multiple, Bacterial/genetics , Drug Therapy, Combination , Serratia marcescens/drug effects , Serratia marcescens/genetics , Serratia marcescens/isolation & purification , Enterobacter cloacae/drug effects , Enterobacter cloacae/genetics , Enterobacter cloacae/isolation & purification , Bacterial Proteins/genetics , Bacterial Proteins/metabolism
2.
Lancet Microbe ; 5(4): e345-e354, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38458206

ABSTRACT

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.


Subject(s)
Antibiotics, Antitubercular , HIV Seropositivity , Mycobacterium tuberculosis , Tuberculosis, Pulmonary , Tuberculosis , United States , Humans , Male , Adult , Female , Antibiotics, Antitubercular/therapeutic use , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/microbiology , Rifampin/pharmacology , Rifampin/therapeutic use , Uganda , Prospective Studies , Bacterial Load , Microscopy , Sensitivity and Specificity , Mycobacterium tuberculosis/genetics , Tuberculosis/drug therapy , HIV Seropositivity/drug therapy
4.
BMC Infect Dis ; 24(1): 190, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38350885

ABSTRACT

BACKGROUND: The World Health Organization endorsed Truenat MTB rapid molecular assay in 2020 and recommended additional in-country evaluation studies before uptake. We evaluated the accuracy and operational feasibility of Truenat MTB assay (Truenat) in comparison with GeneXpert Ultra and culture. METHODS: In a cross-sectional study of 250 presumptive TB patients, participants were requested to provide a sputum sample on the day of their visit to the clinic. The sputum sample was homogenized and a portion was tested using GeneXpert Ultra as per the routine standard procedure and the other portion was tested using Truenat assay at the clinic laboratory. The second sample portion was processed for Concentrated Fluorescent smear Microscopy (CFM), LJ, and MGIT cultures. Truenat sensitivity and specificity were compared to GeneXpert Ultra and culture. Test performance characteristics and operational feasibility assessment data through interview of the study laboratory staff were also collected and summarized as proportions and percentages. RESULTS: Of the 250 participants recruited in the study, the sensitivity and specificity of Truenat was n/N (%, 95%CI); 66/82 (80.5, 70.2-88.4) and 156/159 (98.1, 94.5-99.6) when compared with Ultra, 50/64 (89.3, 66.0-87.4) and 166/180 (92.2, 87.2-95.6) when compared with LJ, 58/71 (81.7,70.7-89.8) and 131/138 (94.9, 89.8-97.9) when compared to MGIT culture and 59/73 (80.8, 69.9-89.1) and 159/169 (94.1,89.3-97.1) when compared to LJ and/or MGIT culture. The sensitivity of Truenat was lower, 14/23 (60.9, 40.6-82.8) among smear-negative compared to 45/50 (90.0, 78.1-96.6) among smear-positive participants but not different by HIV status. There were no special training needs especially among laboratory personnel with previous GeneXpert /molecular test experience, 19/242 (7.8%) error/invalid, and 12 (17,4%) uninterpretable/indeterminate results mainly for rifampicin resistance determination. However, there were 3 (3.5%) of GeneXpert Ultra indeterminate results. CONCLUSION: Among presumptive TB patients in Uganda, the Truenat assay has high sensitivity and specificity. The Truenat assay has acceptable operational feasibility attributes when compared with the GeneXpert Assay.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Pulmonary , Humans , Rifampin , Mycobacterium tuberculosis/genetics , Uganda , Cross-Sectional Studies , Sputum , Tuberculosis, Pulmonary/diagnosis , Sensitivity and Specificity
5.
BMC Infect Dis ; 24(1): 233, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38383310

ABSTRACT

BACKGROUND: Tuberculosis (TB) is a major cause of mortality worldwide. Children and people living with HIV (PLHIV) have an increased risk of mortality, particularly in the absence of rapid diagnosis. The main challenges of diagnosing TB in these populations are due to the unspecific and paucibacillary disease presentation and the difficulty of obtaining respiratory samples. Thus, novel diagnostic strategies, based on non-respiratory specimens could improve clinical decision making and TB outcomes in high burden TB settings. We propose a multi-country, prospective diagnostic evaluation study with a nested longitudinal cohort evaluation to assess the performance of a new stool-based qPCR, developed by researchers at Baylor College of Medicine (Houston, Texas, USA) for TB bacteriological confirmation with promising results in pilot studies. METHODS: The study will take place in high TB/HIV burden countries (Mozambique, Eswatini and Uganda) where we will enroll, over a period of 30 months, 650 PLHIV (> 15) and 1295 children under 8 years of age (irrespective of HIV status) presenting pressumptive TB. At baseline, all participants will provide clinical history, complete a physical assessment, and undergo thoracic chest X-ray imaging. To obtain bacteriological confirmation, participants will provide respiratory samples (1 for adults, 2 in children) and 1 stool sample for Xpert Ultra MTB/RIF (Cepheid, Sunnyvale, CA, USA). Mycobacterium tuberculosis (M.tb) liquid culture will only be performed in respiratory samples and lateral flow lipoarabinomannan (LF-LAM) in urine following WHO recommendations. Participants will complete 2 months follow-up if they are not diagnosed with TB, and 6 months if they are. For analytical purposes, the participants in the pediatric cohort will be classified into "confirmed tuberculosis", "unconfirmed tuberculosis" and "unlikely tuberculosis". Participants of the adult cohort will be classified as "bacteriologically confirmed TB", "clinically diagnosed TB" or "not TB". We will assess accuracy of the novel qPCR test compared to bacteriological confirmation and Tb diagnosis irrespective of laboratory results. Longitudinal qPCR results will be analyzed to assess its use as treatment response monitoring. DISCUSSION: The proposed stool-based qPCR is an innovation because both the strategy of using a non-sputum based sample and a technique specially designed to detect M.tb DNA in stool. PROTOCOL REGISTRATION DETAILS: ClinicalTrials.gov Identifier: NCT05047315.


Subject(s)
HIV Infections , Mycobacterium tuberculosis , Tuberculosis, Pulmonary , Tuberculosis , Adult , Child , Humans , Eswatini , HIV Infections/complications , HIV Infections/diagnosis , Mozambique , Multicenter Studies as Topic , Prospective Studies , Sensitivity and Specificity , Tuberculosis/diagnosis , Tuberculosis, Pulmonary/diagnosis , Uganda
6.
BMC Infect Dis ; 24(1): 70, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38200467

ABSTRACT

BACKGROUND: Mixed M. tuberculosis (MTB) infection occurs when one is infected with more than one clonally distinct MTB strain. This form of infection can assist MTB strains to acquire additional mutations, facilitate the spread of drug-resistant strains, and boost the rate of treatment failure. Hence, the presence of mixed MTB infection could affect the performance of some rapid molecular diagnostic tests such as Line Probe Assay (LPA) and GeneXpert MTB/RIF (Xpert) assays. METHODS: This was a cross-sectional study that used sputum specimens collected from participants screened for STREAM 2 clinical trial between October 2017 and October 2019. Samples from 62 MTB smear-positive patients and rifampicin-resistant patients from peripheral health facilities were processed for Xpert and LPA as screening tests for eligibility in the trial. From November 2020, processed stored sputum samples were retrieved and genotyped to determine the presence of mixed-MTB strain infection using a standard 24-locus Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem-Repeat (MIRU-VNTR). Samples with at least 20/24 MIRU-VNTR loci amplified were considered for analysis. Agar proportional Drug Susceptibility Test (DST) was performed on culture isolates of samples that had discordant results between LPA and Xpert. The impact of the presence of mixed-MTB strain on Xpert and LPA test interpretation was analyzed. RESULTS: A total of 53/62 (85%) samples had analyzable results from MIRU-VNTR. The overall prevalence of mixed-MTB infection was 5/53 (9.4%). The prevalence was highest among male's 3/31 (9.7%) and among middle-aged adults, 4/30 (33.3%). Lineage 4 of MTB contributed 3/5 (60.0%) of the mixed-MTB infection prevalence. Having mixed MTB strain infection increased the odds of false susceptible Xpert test results (OR 7.556, 95% CI 0.88-64.44) but not for LPA. Being HIV-positive (P = 0.04) independently predicted the presence of mixed MTB infection. CONCLUSIONS: The presence of mixed-MTB strain infection may affect the performance of the GeneXpert test but not for LPA. For patients with high pre-test probability of rifampicin resistance, an alternative rapid method such as LPA should be considered.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Tuberculosis , Adult , Middle Aged , Humans , Male , Rifampin/pharmacology , Rifampin/therapeutic use , Uganda/epidemiology , Cross-Sectional Studies , Pathology, Molecular , Mycobacterium tuberculosis/genetics , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/drug therapy
7.
Res Sq ; 2023 Sep 28.
Article in English | MEDLINE | ID: mdl-37841871

ABSTRACT

Background: We evaluated the effect of mixed-MTB strain infection on the performance of Line Probe Assay (LPA) and GeneXpert MTB/RIF (Xpert) assays among patients initiating MDR-TB treatment in Uganda. Methods: This was a cross-sectional study using sputum specimens collected from participants screened for STREAM 2 clinical trial between October 2017 and October 2019. Samples from 62 MTB smear-positive patients and rifampicin-resistant patients from the peripheral health facilities were processed for Xpert and LPA as screening tests for eligibility in the trial. From November 2020, processed stored sputum samples were retrieved and genotyped to determine the presence of mixed-MTB strain infection using a standard 24-locus Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem-Repeat (MIRU-VNTR). Samples with at least 20/24 MIRU-VNTR loci amplified were considered for analysis. Agar proportional Drug Susceptibility Test (DST) was performed on culture isolates of samples that had discordant results between LPA and Xpert. The impact of the presence of mixed-MTB strain on Xpert and LPA test interpretation was analyzed. Results: A total of 53/62 (85%) samples had analyzable results from MIRU-VNTR. The overall prevalence of mixed-MTB infection was 5/53 (9.4%). The prevalence was highest among males 3/33 (9.7%) and among middle-aged adults, 4/30 (13.3%). Lineage 4 of MTB contributed 3/33 (9.1%) of the mixed-MTB infection prevalence. Having mixed MTB strain infection increased the odds of false susceptible Xpert test results (OR 7.556, 95% CI 0.88-64.44) but not for LPA. Being HIV-positive (P=0.04) independently predicted the presence of mixed MTB infection. Conclusions: The presence of mixed-MTB strain infection may affect the performance of the GeneXpert test but not for LPA. For patients with high pre-test probability of rifampicin resistance, an alternative rapid method such as LPA should be considered.

8.
PLoS One ; 18(8): e0284545, 2023.
Article in English | MEDLINE | ID: mdl-37590288

ABSTRACT

BACKGROUND: Drug-Resistant Tuberculosis (DR-TB) is one of the major challenges to TB control. DESIGN AND METHODS: This was a blinded, laboratory-based cross-sectional study using sputum samples or culture isolates. Samples were from patients with rifampicin-resistant-TB and/or with high risk for isoniazid (INH) resistance and/or 2nd line fluoroquinolones (FQ) and injectable agents (IAs). The diagnostic accuracy of the Xpert® MTB/XDR test was compared to MGIT960 and the Hain Genotype® MTBDRplus and MDRsl assays (LPA) as reference DST methods. Factors for laboratory uptake of the Xpert® MTB/XDR test were also evaluated. RESULTS: Of the 100 stored sputum samples included in this study, 65/99 (65.6%) were resistant to INH, 5/100 (5.0%) were resistant to FQ and none were resistant to IAs using MGIT960. The sensitivity and specificity, n (%; 95% Confidence Interval, CI) of Xpert® MTB/XDR test for; INH was 58 (89.2; 79.1-95.5) and 30 (88.2; 72.5-96.6) and for FQ; 4 (80.0; 28.3-99.4) and 95 (100; 96.2-100), respectively. Using LPA as a reference standard, a total of 52/98 (53.1%) were resistant to INH, 3/100 (3.0%) to FQ, and none to IA. The sensitivity and specificity, n (%; 95%CI) of Xpert® MTB/XDR test compared to LPA for; INH was 50 (96.1; 86.7-99.5) and 34 (74.0; 58.8-85.7) for FQ 3 (100; 29.2-100) and 96 (99.0; 94.3-99.9) respectively. The factors for laboratory uptake and roll-out of the Xpert® MTB/XDR test included: no training needed for technicians with, and one day for those without, previous Xpert-ultra experience, recording and reporting needs were not different from those of Xpert-ultra, the error rate was 4/100 (4%), one (1%) indeterminate rate and test turn-around-time were 1hr/45 minutes. CONCLUSION: There is high sensitivity and specificity of Xpert® MTB/XDR test for isoniazid and fluoroquinolones. There are acceptable Xpert® MTB/XDR test attributes for the test uptake and roll-out.


Subject(s)
Mycobacterium tuberculosis , Humans , Mycobacterium tuberculosis/genetics , Uganda , Cross-Sectional Studies , Isoniazid/pharmacology , Fluoroquinolones/pharmacology
9.
medRxiv ; 2023 Apr 05.
Article in English | MEDLINE | ID: mdl-37066316

ABSTRACT

Background: Drug-Resistant Tuberculosis (DR-TB) is one of the key challenges toward TB control. There is an urgent need for rapid and accurate drug susceptibility tests (DST) for the most commonly used 1 st and 2 nd line TB drugs. Design and Methods: In a blinded, laboratory-based cross-sectional study, we set out to validate the performance of the Xpert ® MTB/XDR test for DST of M. tuberculosis . Sputum samples or culture isolates collected between January 2020 and December 2021 from patients with rifampicin resistance -TB and/or with higher suspicion index for isoniazid (INH) resistance and/or 2 nd line fluoroquinolones (FQ) and injectable agents (IAs) were tested using the Xpert ® MTB/XDR test from 11/September 2021 to 26/May /2022. Diagnostic accuracy and factors for laboratory uptake of Xpert ® MTB/XDR test were compared to MGIT960 and the Hain Genotype® MTBDR plus and MDRsl assays (LPA) as reference DST methods. Results: A total of 100 stored sputum samples were included in this study. Of the samples tested using MGIT960, 65/99 (65.6%) were resistant to INH, 5/100 (5.0%) resistant to FQ and none were resistant to IAs. The sensitivity and specificity, n (%; 95%Confidence Interval, CI) of Xpert ® MTB/XDR test for; INH were 58 (89.2; 79.1-95.5) and 30 (88.2; 72.5-96.6), FQ; 4 (80.0; 28.3-99.4) and 95 (100; 96.2-100), respectively. The specificity for AIs was 100 (100; 96.3-100). Using LPA as a reference standard, a total of 52/98 (53.1%) were resistant to INH, 3/100 (3.0%) to FQ, and none to IA. The sensitivity and specificity, n (%; 95%CI) of Xpert ® MTB/XDR test compared to LPA for; INH was 50 (96.1; 86.7-99.5) and 34 (74.0; 58.8-85.7) and FQ 3 (100; 29.2-100) and 96 (99.0; 94.3-99.9) respectively. The specificity of IAs was 96 (100; 96.2-100). The factors for laboratory uptake and roll-out included; no training needed for technicians with previous Xpert-ultra experience and one day for those without, recording and reporting needs were not different from those of Xpert ultra, the error rate was 4/100 (4%), no uninterpretable results reported, test turn-around-time was 1hr/45 minutes and workflow similar to that of the Xpert-ultra test. Conclusion: There is high sensitivity and specificity of Xpert ® MTB/XDR test for isoniazid, fluoroquinolones, and Injectable agents. There are acceptable Xpert ® MTB/XDR test attributes for test uptake and roll-out.

11.
BMC Cardiovasc Disord ; 22(1): 464, 2022 11 04.
Article in English | MEDLINE | ID: mdl-36333654

ABSTRACT

BACKGROUND: Tuberculosis (TB) and its risk factors are independently associated with cardiovascular disease (CVD). We determined the prevalence and associations of CVD risk factors among people with drug-resistant tuberculosis (DRTB) in Uganda. METHODS: In this cross-sectional study, we enrolled people with microbiologically confirmed DRTB at four treatment sites in Uganda between July to December 2021. The studied CVD risk factors were any history of cigarette smoking, diabetes mellitus (DM) hypertension, high body mass index (BMI), central obesity and dyslipidaemia. We used modified Poisson regression models with robust standard errors to determine factors independently associated with each of dyslipidaemia, hypertension, and central obesity. RESULTS: Among 212 participants, 118 (55.7%) had HIV. Overall, 196 (92.5%, 95% confidence interval (CI) 88.0-95.3) had ≥ 1 CVD risk factor. The prevalence; 95% CI of individual CVD risk factors was: dyslipidaemia (62.5%; 55.4-69.1), hypertension (40.6%; 33.8-47.9), central obesity (39.3%; 32.9-46.1), smoking (36.3%; 30.1-43.1), high BMI (8.0%; 5.0-12.8) and DM (6.5%; 3.7-11.1). Dyslipidaemia was associated with an increase in glycated haemoglobin (adjusted prevalence ratio (aPR) 1.14, 95%CI 1.06-1.22). Hypertension was associated with rural residence (aPR 1.89, 95% CI 1.14-3.14) and previous history of smoking (aPR 0.46, 95% CI 0.21-0.98). Central obesity was associated with increasing age (aPR 1.02, 95%CI 1.00-1.03), and elevated diastolic blood pressure (aPR 1.03 95%CI 1.00-1.06). CONCLUSION: There is a high prevalence of CVD risk factors among people with DRTB in Uganda, of which dyslipidaemia is the commonest. We recommend integrated services for identification and management of CVD risk factors in DRTB.


Subject(s)
Cardiovascular Diseases , Diabetes Mellitus , Dyslipidemias , Hypertension , Tuberculosis, Multidrug-Resistant , Humans , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/etiology , Risk Factors , Cross-Sectional Studies , Obesity, Abdominal/diagnosis , Obesity, Abdominal/epidemiology , Obesity, Abdominal/complications , Uganda/epidemiology , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Multidrug-Resistant/epidemiology , Hypertension/diagnosis , Hypertension/epidemiology , Hypertension/complications , Dyslipidemias/diagnosis , Dyslipidemias/epidemiology , Dyslipidemias/complications , Heart Disease Risk Factors , Diabetes Mellitus/diagnosis , Diabetes Mellitus/epidemiology , Prevalence , Obesity/complications
12.
Front Pediatr ; 10: 880355, 2022.
Article in English | MEDLINE | ID: mdl-35813373

ABSTRACT

Background: Children living with HIV (CLHIV) and children who are exposed to HIV but uninfected (CHEU) are at increased risk of developing malnutrition. Severely malnourished children have high mortality rates, but mortality is higher in CLHIV/CHEU. This study aims to investigate whether empiric use of an antibiotic with greater antimicrobial sensitivity (ceftriaxone) than standard-of-care (ampicillin plus gentamicin) will reduce mortality among CLHIV/CHEU admitted with severe acute malnutrition. Methods: This is an open label randomized controlled trial involving 300 children; 76 CLHIV and 224 CHEU. The participants are being randomized to receive 1 week of ceftriaxone (n = 150) or standard-of-care (ampicillin/gentamicin) (n = 150), in addition to other routine care. The trial's primary outcome is in-hospital mortality. Secondary outcomes are: length of hospitalization; weight-for-height, weight-for-age and height-for-age z-scores; and pattern/antimicrobial sensitivity of pathogens. In addition, 280 severely malnourished children of unknown serostatus will be tested for HIV at admission to determine the prevalence and factors associated with HIV-infection. Furthermore, all the CLHIV on LPV/r will each provide sparse pharmacokinetic (PK) samples to evaluate the PK of LPV/r among malnourished children. In this PK sub-study, geometric means of steady-state LPV PK parameters [Area Under the Curve (AUC) 0-12h , maximum concentration (Cmax) and concentration at 12 h after dose (C12h)] will be determined. They will then be put in pharmacokinetic-pharmacodynamic (PK-PD) models to determine optimal doses for the study population. Discussion: This study will ascertain whether antibiotics with higher sensitivity patterns to common organisms in Uganda and similar settings, will produce better treatment outcomes. The study will also provide insights into the current pattern of organisms isolated from blood cultures and their antimicrobial sensitivities, in this population. In addition, the study will ascertain whether there has been a significant change in the prevalence of HIV-infection among children presenting with severe malnutrition in the WHO recommended option B plus era, while determining the social/structural factors associated with HIV-infection. There will also be an opportunity to study PK parameters of antiretroviral drugs among severely malnourished children which is rarely done, and yet it is very important to understand the dosing requirements of this population. Trial Registration: ClinicalTrials.gov, identifier: NCT05051163.

13.
J Med Case Rep ; 16(1): 214, 2022 May 31.
Article in English | MEDLINE | ID: mdl-35637524

ABSTRACT

BACKGROUND: Human immunodeficiency virus/tuberculosis coinfections have amplified the multidrug-resistant tuberculosis pandemic in many countries in Sub-Saharan Africa, and multidrug-resistant tuberculosis has become a major public health threat. There is a paucity of data on severe complications of multidrug-resistant tuberculosis in the context of human immunodeficiency virus coinfection despite the increasing prevalence of multidrug-resistant tuberculosis/human immunodeficiency virus coinfection and the complexity of multidrug-resistant tuberculosis treatment. This report describes a rare case of complicated multidrug-resistant tuberculosis in a human immunodeficiency virus-positive individual. CASE PRESENTATION: A 39-year-old human immunodeficiency virus-positive Ugandan male on anti-retroviral therapy for 6 years, who had recently completed treatment for drug-susceptible tuberculosis from a public hospital, presented to the tuberculosis ward of Mulago National Referral Hospital with worsening respiratory symptoms including persistent cough with purulent sputum, fever, right chest pain, and shortness of breath. On admission, a diagnosis of drug-resistant tuberculosis was made following a positive sputum Xpert MTB/Rif test with rifampicin resistance. Culture-based tuberculosis tests and line probe assay confirmed multidrug-resistant tuberculosis. The patient was given multidrug-resistant tuberculosis treatment that included bedaquiline, isoniazid, prothionamide, clofazimine, ethambutol, levofloxacin, and pyrazinamide and switched to second-line anti-retroviral therapy that included tenofovir/lamivudine/lopinavir/ritonavir. Chest X-ray revealed a hydro-pneumothorax, following which a chest tube was inserted. With persistent bubbling from the chest tube weeks later and a check chest X-ray that showed increasing pleural airspace (pneumothorax) and appearance of a new air-fluid level, chest computed tomography scan was performed, revealing a bronchopleural fistula in the right hemithorax. The computed tomography scan also revealed a pyo-pneumothorax and lung collapse involving the right middle and lower lobes as well as a thick-walled cavity in the right upper lobe. With the pulmonary complications, particularly the recurrent pneumothorax, bronchopleural fistula, and empyema thoracis, cardiothoracic surgeons were involved, who managed the patient conservatively and maintained the chest tube. The patient continued to be ill with recurrent pneumothorax despite the chest tube, until relatives opted for discharge against medical advice. CONCLUSIONS: Complicated human immunodeficiency virus-related multidrug-resistant tuberculosis is not uncommon in settings of high human immunodeficiency virus/tuberculosis prevalence and is often associated with significant morbidity and mortality. Early diagnosis and treatment of multidrug-resistant tuberculosis, with rigorous monitoring for human immunodeficiency virus-positive individuals, is necessary to prevent debilitating complications.


Subject(s)
Coinfection , Fistula , HIV Infections , HIV Seropositivity , Pleural Diseases , Pneumothorax , Tuberculosis, Multidrug-Resistant , Adult , Coinfection/drug therapy , HIV , HIV Infections/complications , Humans , Male , Pneumothorax/diagnostic imaging , Tuberculosis, Multidrug-Resistant/complications , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/drug therapy
14.
BMC Infect Dis ; 22(1): 363, 2022 Apr 11.
Article in English | MEDLINE | ID: mdl-35410160

ABSTRACT

BACKGROUND: Second-line drug resistance (SLD) among tuberculosis (TB) patients is a serious emerging challenge towards global control of the disease. We characterized SLD-resistance conferring-mutations among TB patients with rifampicin and/or isoniazid (RIF and/or INH) drug-resistance tested at the Uganda National TB Reference Laboratory (NTRL) between June 2017 and December 2019. METHODS: This was a descriptive cross-sectional secondary data analysis of 20,508 M. tuberculosis isolates of new and previously treated patients' resistant to RIF and/or INH. DNA strips with valid results to characterise the SLD resistance using the commercial Line Probe Assay Genotype MTBDRsl Version 2.0 Assay (Hain Life Science, Nehren, Germany) were reviewed. Data were analysed with STATAv15 using cross-tabulation for frequency and proportions of known resistance-conferring mutations to injectable agents (IA) and fluoroquinolones (FQ). RESULTS: Among the eligible participants, 12,993/20,508 (63.4%) were male and median (IQR) age 32 (24-43). A total of 576/20,508 (2.8%) of the M. tuberculosis isolates from participants had resistance to RIF and/or INH. These included; 102/576 (17.7%) single drug-resistant and 474/576 (82.3%) multidrug-resistant (MDR) strains. Only 102 patients had test results for FQ of whom 70/102 (68.6%) and 01/102 (0.98%) had resistance-conferring mutations in the gyrA locus and gyrB locus respectively. Among patients with FQ resistance, gyrAD94G 42.6% (30.0-55.9) and gyrA A90V 41.1% (28.6-54.3) mutations were most observed. Only one mutation, E540D was detected in the gyrB locus. A total of 26 patients had resistance-conferring mutations to IA in whom, 20/26 77.0% (56.4-91.0) had A1401G mutation in the rrs gene locus. CONCLUSIONS: Our study reveals a high proportion of mutations known to confer high-level fluoroquinolone drug-resistance among patients with rifampicin and/or isoniazid drug resistance. Utilizing routinely generated laboratory data from existing molecular diagnostic methods may aid real-time surveillance of emerging tuberculosis drug-resistance in resource-limited settings.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Adult , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Cross-Sectional Studies , Drug Resistance, Multiple, Bacterial/genetics , Female , Fluoroquinolones/therapeutic use , Humans , Isoniazid/pharmacology , Isoniazid/therapeutic use , Male , Microbial Sensitivity Tests , Mutation , Rifampin/pharmacology , Rifampin/therapeutic use , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Multidrug-Resistant/epidemiology , Uganda/epidemiology , Young Adult
15.
Trop Med Health ; 50(1): 16, 2022 Feb 17.
Article in English | MEDLINE | ID: mdl-35177126

ABSTRACT

BACKGROUND: Tuberculosis (TB) is one of the leading causes of death globally, and the rise in drug-resistant forms of TB has become a significant threat. Subsequently, it is crucial to explore new, effective and safe anti-TB agents. This study aimed at conducting phytochemical screening, antimycobacterial activity, and acute toxicity of the selected plant species' crude extracts to assess their toxicological potentials and efficacies against TB. METHODS: The aqueous and methanol/dichloromethane (DCM) (1:1) extracts of each selected plant species were subjected to phytochemical screening and antimycobacterial activity using microplate alamar blue assay. For acute toxicity, a single dose (2000 mg/kg) of the aqueous extracts was orally administered to each animal following the Organization for Economic Cooperation and Development (OECD) guidelines No. 425 and then observed for 14 days. The animals were closely observed on the general behavior and clinical signs of toxicity, and body weights were recorded. After the termination of the experiment, hematological, biochemical, and histopathological analyses were performed. RESULTS: The extracts contained alkaloids, flavonoids, tannins, saponins, steroids, terpenoids, resins, cardiac glycosides, phenolic compounds, and coumarins. Aqueous extracts showed moderate to weak activity against the susceptible (H37Rv) M. tuberculosis strain and weak activity against the MDR-TB strain with Minimum Inhibitory Concentrations (MIC µg/mL) ranging from 293.0-2344.0 and 1172.0-4688.0, respectively. Methanol/DCM extracts showed significant to moderate activity against the susceptible TB strain and moderate to weak activity against the MDR-TB strain with MIC (µg/mL) ranging from 98.0-586.0 and 293.0-781.0, respectively. One mortality was recorded from the A. coriaria treated group following the acute toxicity tests, but the LD50 of all the extracts was estimated to be above 2000 mg/kg. Histopathological analyses did not show any significant lesions in the examined organs except those from the A. coriaria treated group. CONCLUSION: Phytochemical screening of the extracts revealed the presence of alkaloids, tannins, saponins, flavonoids, steroids, terpenoids, resins, cardiac glycosides, phenolic compounds, and coumarins. All the methanol/DCM extracts of the plant species studied have promising antimycobacterial activity. The selected plant extracts studied exhibited low acute toxicity levels except for A. coriaria and could be safe for formulations into herbal products.

16.
Microbiol Spectr ; 10(1): e0210021, 2022 02 23.
Article in English | MEDLINE | ID: mdl-35019686

ABSTRACT

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.


Subject(s)
Bacterial Load , Feces/microbiology , Molecular Diagnostic Techniques/methods , Mycobacterium tuberculosis/genetics , Tuberculosis/diagnosis , Tuberculosis/microbiology , Tuberculosis/therapy , Adult , Cross-Sectional Studies , Female , HIV Infections , Humans , Male , Microscopy , Sensitivity and Specificity , Sputum
17.
Afr Health Sci ; 22(3): 62-71, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36910377

ABSTRACT

Background: Sexually transmitted diseases (STDs) management in sub-Saharan Africa is syndromic but molecular diagnostics provide quicker, sensitive diagnosis and treatment. Effective STD control hinges on identification and treatment of infected persons and sexual partner contact tracing. Objectives: This study assessed feasibility of using the Xpert CT/NG test to identify prevalent Chlamydia trachomatis (CT) and Neisseria gonorrhea (NG) infections among STD clinic attendees and their sexual partners and tested for antimicrobial resistance for N. gonorrhea. Methods: A cross-sectional study was conducted at 4 outpatient STD clinics in Kampala, Uganda from February 2019 to October 2019. Participants received a syndromic diagnosis, were tested for NG and CT, as well as their sexual partners. Urine (men) and high vaginal swabs (women) were collected, examined using Xpert CT/NG assay. A total of 79 participants were enrolled at baseline of whom 25 had CT/NG. 21 partners of infected baseline participants and 7 partners of the 21 primary partners were enrolled. Results: The mean age of the reported sexual partners was 26 (18-43) years. The prevalence of NG was 25% at baseline and 18 % for CT. Nine (11.4%) people were dually infected. Men were more likely to have NG (p<0.001) at multivariable level. Two participants tested HIV-1 positive. On microbiological culture, 8 samples (2.5%) grew NG and all were resistant to penicillin, ciprofloxacin. For CT, we found a preponderance of the F-serovar in this population. Conclusion: The most prevalent organism was Neisseria gonorrhea. Generally, the prevalence of CT and NG was high. Infection proportions increased among primary partners, particularly women. Etiologic testing without partner tracing and treatment may underestimate burden of CT/NG in this population and contribute to re-infection.


Subject(s)
Chlamydia Infections , Gonorrhea , Sexually Transmitted Diseases , Male , Female , Humans , Adult , Gonorrhea/epidemiology , Chlamydia trachomatis , Anti-Bacterial Agents , Prevalence , Cross-Sectional Studies , Uganda , Chlamydia Infections/diagnosis , Chlamydia Infections/epidemiology , Chlamydia Infections/microbiology , Drug Resistance, Bacterial , Sexually Transmitted Diseases/epidemiology , Neisseria gonorrhoeae
18.
Sci Rep ; 11(1): 24486, 2021 12 29.
Article in English | MEDLINE | ID: mdl-34966183

ABSTRACT

Information on microbiota dynamics in pulmonary tuberculosis (TB) in Africa is scarce. Here, we sequenced sputa from 120 treatment-naïve TB patients in Uganda, and investigated changes in microbiota of 30 patients with treatment-response follow-up samples. Overall, HIV-status and anti-TB treatment were associated with microbial structural and abundance changes. The predominant phyla were Bacteroidetes, Firmicutes, Proteobacteria, Fusobacteria and Actinobacteria, accounting for nearly 95% of the sputum microbiota composition; the predominant genera across time were Prevotella, Streptococcus, Veillonella, Haemophilus, Neisseria, Alloprevotella, Porphyromonas, Fusobacterium, Gemella, and Rothia. Treatment-response follow-up at month 2 was characterized by a reduction in abundance of Mycobacterium and Fretibacterium, and an increase in Ruminococcus and Peptococcus; month 5 was characterized by a reduction in Tannerella and Fusobacterium, and an increase in members of the family Neisseriaceae. The microbiota core comprised of 44 genera that were stable during treatment. Hierarchical clustering of this core's abundance distinctly separated baseline (month 0) samples from treatment follow-up samples (months 2/5). We also observed a reduction in microbial diversity with 9.1% (CI 6-14%) of the structural variation attributed to HIV-status and anti-TB treatment. Our findings show discernible microbiota signals associated with treatment with potential to inform anti-TB treatment response monitoring.


Subject(s)
Sputum/microbiology , Tuberculosis, Pulmonary/microbiology , Adult , Antitubercular Agents/therapeutic use , Bacteria/drug effects , Bacteria/isolation & purification , Female , Humans , Longitudinal Studies , Male , Microbiota/drug effects , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/epidemiology , Uganda/epidemiology
19.
Int J Infect Dis ; 113: 355-358, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34757007

ABSTRACT

Real-time polymerase chain reaction (RT-PCR) remains the gold standard for detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This study tested the performance of a pooled testing strategy for RT-PCR and its cost-effectiveness. In total, 1280 leftover respiratory samples collected between 19 April and 6 May 2021 were tested in 128 pools of 10 samples each, out of which 16 pools were positive. The positivity rate of the unpooled samples was 1.9% (24/1280). After parallel testing using the individual and pooled testing strategies, positive agreement was 100% and negative agreement was 99.8%. The overall median cycle threshold (Ct) value of the unpooled samples was 29.8 (interquartile range 22.3-34.3). Pools that remained positive when compared with the results of individual samples had lower median Ct values compared with those that turned out to be negative (28.8 versus 34.8; P=0.0.035). Pooled testing reduced the cost >4-fold. Pooled testing may be a more cost-effective approach to diagnose SARS-CoV-2 in resource-limited settings without compromising diagnostic performance.


Subject(s)
COVID-19 , SARS-CoV-2 , Cost-Benefit Analysis , Humans , Real-Time Polymerase Chain Reaction , Sensitivity and Specificity , Uganda
20.
J Clin Tuberc Other Mycobact Dis ; 25: 100286, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34816021

ABSTRACT

Tuberculosis (TB) resistance to rifampicin, the most powerful drug leads to increase in mortality. Globally, half a million new patients develop such resistant TB each year, coupled with both inappropriate diagnosis and treatment initiation. We report a case of rifampicin resistant Mycobacterium tuberculosis whose rifampicin resistance was missed by Xpert MTB/RIF Assay G4 but detected by the Xpert MTB/RIF Ultra assay at different time points leading to increased delays for MDR-TB treatment initiation at Mulago Hospital, Kampala, Uganda. Our case report compels greater urgency in accelerating the transition to the newer assay, Ultra, to benefit from higher sensitivity of rifampicin resistance detection.

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