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1.
Nat Immunol ; 23(9): 1324-1329, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36038709

RESUMO

T cells can contribute to clearance of respiratory viruses that cause acute-resolving infections such as SARS-CoV-2, helping to provide long-lived protection against disease. Recent studies have suggested an additional role for T cells in resisting overt infection: pre-existing cross-reactive responses were preferentially enriched in healthcare workers who had abortive infections1, and in household contacts protected from infection2. We hypothesize that such early viral control would require pre-existing cross-reactive memory T cells already resident at the site of infection; such airway-resident responses have been shown to be critical for mediating protection after intranasal vaccination in a murine model of SARS-CoV3. Bronchoalveolar lavage samples from the lower respiratory tract of healthy donors obtained before the COVID-19 pandemic revealed airway-resident, SARS-CoV-2-cross-reactive T cells, which correlated with the strength of human seasonal coronavirus immunity. We therefore demonstrate the potential to harness functional airway-resident SARS-CoV-2-reactive T cells in next-generation mucosal vaccines.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Antivirais , Reações Cruzadas , Humanos , Camundongos , Pandemias , Sistema Respiratório
2.
Nat Immunol ; 19(12): 1299-1308, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30374129

RESUMO

Colonization of the upper respiratory tract by pneumococcus is important both as a determinant of disease and for transmission into the population. The immunological mechanisms that contain pneumococcus during colonization are well studied in mice but remain unclear in humans. Loss of this control of pneumococcus following infection with influenza virus is associated with secondary bacterial pneumonia. We used a human challenge model with type 6B pneumococcus to show that acquisition of pneumococcus induced early degranulation of resident neutrophils and recruitment of monocytes to the nose. Monocyte function was associated with the clearance of pneumococcus. Prior nasal infection with live attenuated influenza virus induced inflammation, impaired innate immune function and altered genome-wide nasal gene responses to the carriage of pneumococcus. Levels of the cytokine CXCL10, promoted by viral infection, at the time pneumococcus was encountered were positively associated with bacterial load.


Assuntos
Coinfecção/imunologia , Influenza Humana/imunologia , Mucosa Nasal/imunologia , Infecções Pneumocócicas/imunologia , Quimiocina CXCL10/imunologia , Quimiotaxia de Leucócito/imunologia , Método Duplo-Cego , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Monócitos/imunologia , Neutrófilos/imunologia , Streptococcus pneumoniae
3.
J Infect Dis ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984706

RESUMO

BACKGROUND: In Malawi, the national pneumococcal conjugate vaccine (PCV13) demonstrated less herd immunity than the USA, likely due to higher natural pneumococcal carriage rates. We assessed PCV13 efficacy against experimental pneumococcal carriage in healthy Malawian adults. We explored how natural carriage (pneumococcal carriage of any other serotype apart from 6B) influenced experimental carriage rates and vaccine efficacy. METHODS: Healthy adults aged 18-40 were randomly assigned PCV13 (n=98) or saline (n=106), followed by intranasal SPN 6B inoculation at 20,000 (n=40), 80,000 (n=74), or 160,000 (n=90) CFU/100µl, 28 days post-vaccination. We evaluated natural and experimental pneumococcal carriage before and after vaccination on days 2, 7, and 14 post-inoculation using culture and multiplex qPCR targeting lytA/cpsA genes and compared carriage rates by vaccination status. RESULTS: Of 204 participants, 19.6% (40) exhibited experimental carriage, detected by culture and 25.5% (52) by qPCR. Vaccinated individuals had lower experimental carriage rates (10.2%, n=10/98) compared to the placebo group (28.3%, n=30/106). This difference in vaccine efficacy was more pronounced in participants without natural carriage (PCV13=8% n=6/75 vs. placebo=25.9%, n=21/81) compared to those with natural carriage (PCV13=14.8%, n=4/27 vs. placebo=26.5%, n=9/34). Using a log-binomial model, vaccine effectiveness (VE) was 62%, whether assessed by culture or qPCR. Natural carriers had a lower VE of 52% compared to participants with no natural carriage (VE=69%). CONCLUSION: We have shown that PCV13 VE estimate (62%) is robust whether carriage is assessed by culture or qPCR. PCV13 had lower VE in natural carriers compared to those without natural carriage at the inoculation visit.

4.
Bull World Health Organ ; 101(9): 558-570G, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37638357

RESUMO

Objective: To estimate the prevalence of individual chronic conditions and multimorbidity among adults admitted to hospital in countries in sub-Saharan Africa. Methods: We systematically searched MEDLINE®, Embase®, Global Index Medicus, Global Health and SciELO for publications reporting on patient cohorts recruited between 1 January 2010 and 12 May 2023. We included articles reporting prevalence of pre-specified chronic diseases within unselected acute care services (emergency departments or medical inpatient settings). No language restrictions were applied. We generated prevalence estimates using random-effects meta-analysis alongside 95% confidence intervals, 95% prediction intervals and I2 statistics for heterogeneity. To explore associations with age, sex, country-level income status, geographical region and risk of bias, we conducted pre-specified meta-regression, sub-group and sensitivity analyses. Findings: Of 6976 identified studies, 61 met the inclusion criteria, comprising data from 20 countries and 376 676 people. None directly reported multimorbidity, but instead reported prevalence for individual conditions. Among medical admissions, the highest prevalence was human immunodeficiency virus infection (36.4%; 95% CI: 31.3-41.8); hypertension (24.4%; 95% CI: 16.7-34.2); diabetes (11.9%; 95% CI: 9.9-14.3); heart failure (8.2%; 95% CI: 5.6-11.9); chronic kidney disease (7.7%; 95% CI: 3.9-14.7); and stroke (6.8%; 95% CI: 4.7-9.6). Conclusion: Among patients seeking hospital care in sub-Saharan Africa, multimorbidity remains poorly described despite high burdens of individual chronic diseases. Prospective public health studies of multimorbidity burden are needed to generate integrated and context-specific health system interventions that act to maximize patient survival and well-being.


Assuntos
Doença Crônica , Atenção à Saúde , Pacientes , Adulto , Humanos , África Subsaariana/epidemiologia , Hospitais , Estudos Prospectivos
5.
BMC Infect Dis ; 23(1): 79, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750921

RESUMO

BACKGROUND: Compared to the abundance of clinical and genomic information available on patients hospitalised with COVID-19 disease from high-income countries, there is a paucity of data from low-income countries. Our aim was to explore the relationship between viral lineage and patient outcome. METHODS: We enrolled a prospective observational cohort of adult patients hospitalised with PCR-confirmed COVID-19 disease between July 2020 and March 2022 from Blantyre, Malawi, covering four waves of SARS-CoV-2 infections. Clinical and diagnostic data were collected using an adapted ISARIC clinical characterization protocol for COVID-19. SARS-CoV-2 isolates were sequenced using the MinION™ in Blantyre. RESULTS: We enrolled 314 patients, good quality sequencing data was available for 55 patients. The sequencing data showed that 8 of 11 participants recruited in wave one had B.1 infections, 6/6 in wave two had Beta, 25/26 in wave three had Delta and 11/12 in wave four had Omicron. Patients infected during the Delta and Omicron waves reported fewer underlying chronic conditions and a shorter time to presentation. Significantly fewer patients required oxygen (22.7% [17/75] vs. 58.6% [140/239], p < 0.001) and steroids (38.7% [29/75] vs. 70.3% [167/239], p < 0.001) in the Omicron wave compared with the other waves. Multivariable logistic-regression demonstrated a trend toward increased mortality in the Delta wave (OR 4.99 [95% CI 1.0-25.0 p = 0.05) compared to the first wave of infection. CONCLUSIONS: Our data show that each wave of patients hospitalised with SARS-CoV-2 was infected with a distinct viral variant. The clinical data suggests that patients with severe COVID-19 disease were more likely to die during the Delta wave.


Assuntos
COVID-19 , Adulto , Humanos , SARS-CoV-2 , Malaui , Estudos de Coortes , Confiabilidade dos Dados
6.
BMC Health Serv Res ; 23(1): 133, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36759840

RESUMO

BACKGROUND: Perspectives of patients as clients on healthcare offer unique insights into the process and outcomes of care and can facilitate improvements in the quality of services. Differences in the tools used to measure these perspectives often reflect differences in the conceptualization of quality of care and personal experiences. This systematic review assesses the validity and reliability of instruments measuring client experiences and satisfaction with healthcare in low- and middle-income countries (LMICs). METHODS: We performed a systematic search of studies published in PubMed, SCOPUS, and CINAHL. This review was reported according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. Studies describing the development and psychometric properties of client experience and satisfaction with general health care were included in the review. Critical appraisal of study design was undertaken using the Appraisal tool for Cross-Sectional Studies (AXIS). The Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) checklist and Terwee's criteria were used to appraise the psychometric properties of the included studies. A narrative synthesis approach was used in the interpretation of the findings. RESULTS: Of the 7470 records identified, 12 studies with 14 corresponding instruments met the inclusion criteria and were included in the final review. No study assessed all the psychometric properties highlighted by the COSMIN criteria. In most instruments, we found evidence that initial development work incorporated client participation. The most evaluated measurement properties were content validity, internal consistency, and structural validity. Measurement error and responsiveness were not reported in any study. CONCLUSION: Reliability and validity should be considered important elements when choosing or developing an instrument for professionals seeking an effective instrument for use within the population. Our review identified limitations in the psychometric properties of patient experience and satisfaction instruments, and none met all methodological quality standards. Future studies should focus on further developing and testing available measures for their effectiveness in clinical practice. Furthermore, the development of new instruments should incorporate clients' views and be rigorously tested or validated in studies with high methodological quality. TRIAL REGISTRATION: CRD42020150438.


Assuntos
Atenção à Saúde , Países em Desenvolvimento , Humanos , Reprodutibilidade dos Testes , Estudos Transversais , Instalações de Saúde , Psicometria
7.
Clin Infect Dis ; 74(10): 1840-1849, 2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-34407175

RESUMO

BACKGROUND: Sepsis protocols in sub-Saharan Africa are typically extrapolated from high-income settings, yet sepsis in sub-Saharan Africa is likely caused by distinct pathogens and may require novel treatment strategies. Data to guide such strategies are lacking. We aimed to define causes and modifiable factors associated with sepsis outcomes in Blantyre, Malawi, in order to inform the design of treatment strategies tailored to sub-Saharan Africa. METHODS: We recruited 225 adults who met a sepsis case definition defined by fever and organ dysfunction in an observational cohort study at a single tertiary center. Etiology was defined using culture, antigen detection, serology, and polymerase chain reaction. The effect of treatment on 28-day outcomes was assessed using Bayesian logistic regression. RESULTS: There were 143 of 213 (67%) participants living with human immunodeficiency virus (HIV). We identified a diagnosis in 145 of 225 (64%) participants, most commonly tuberculosis (TB; 34%) followed by invasive bacterial infections (17%), arboviral infections (13%), and malaria (9%). TB was associated with HIV infection, whereas malaria and arboviruses with the absence of HIV infection. Antituberculous chemotherapy was associated with survival (adjusted odds ratio for 28-day death, 0.17; 95% credible interval, 0.05-0.49 for receipt of antituberculous therapy). Of those with confirmed etiology, 83% received the broad-spectrum antibacterial ceftriaxone, but it would be expected to be active in only 24%. CONCLUSIONS: Sepsis in Blantyre, Malawi, is caused by a range of pathogens; the majority are not susceptible to the broad-spectrum antibacterials that most patients receive. HIV status is a key determinant of etiology. Novel antimicrobial strategies for sepsis tailored to sub-Saharan Africa, including consideration of empiric antituberculous therapy in individuals living with HIV, should be developed and trialed.


Assuntos
Infecções por HIV , Malária , Sepse , Tuberculose , Adulto , Antibacterianos , Teorema de Bayes , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Malária/complicações , Malaui/epidemiologia , Sepse/complicações , Sepse/tratamento farmacológico , Sepse/epidemiologia , Tuberculose/complicações
8.
Thorax ; 77(11): 1131-1139, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34937802

RESUMO

RATIONALE: Pulmonary tuberculosis (PTB) can cause post-TB lung disease (PTLD) associated with respiratory symptoms, spirometric and radiological abnormalities. Understanding of the predictors and natural history of PTLD is limited. OBJECTIVES: To describe the symptoms and lung function of Malawian adults up to 3 years following PTB-treatment completion, and to determine the evolution of PTLD over this period. METHODS: Adults successfully completing PTB treatment in Blantyre, Malawi were followed up for 3 years and assessed using questionnaires, post-bronchodilator spirometry, 6 min walk tests, chest X-ray and high-resolution CT. Predictors of lung function at 3 years were identified by mixed effects regression modelling. MEASUREMENT AND MAIN RESULTS: We recruited 405 participants of whom 301 completed 3 years follow-up (mean (SD) age 35 years (10.2); 66.6% males; 60.4% HIV-positive). At 3 years, 59/301 (19.6%) reported respiratory symptoms and 76/272 (27.9%) had abnormal spirometry. The proportions with low FVC fell from 57/285 (20.0%) at TB treatment completion to 33/272 (12.1%), while obstruction increased from and 41/285 (14.4%) to 43/272 (15.8%) at 3 years. Absolute FEV1 and FVC increased by mean 0.03 L and 0.1 L over this period, but FEV1 decline of more than 0.1 L was seen in 73/246 (29.7%). Higher spirometry values at 3 years were associated with higher body mass index and HIV coinfection at TB-treatment completion. CONCLUSION: Spirometric measures improved over the 3 years following treatment, mostly in the first year. However, a third of PTB survivors experienced ongoing respiratory symptoms and abnormal spirometry (with accelerated FEV1 decline). Effective interventions are needed to improve the care of this group of patients.


Assuntos
Pneumopatias , Tuberculose Pulmonar , Adulto , Broncodilatadores/uso terapêutico , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/diagnóstico por imagem , Malaui/epidemiologia , Masculino , Estudos Prospectivos , Espirometria , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/tratamento farmacológico , Capacidade Vital
9.
Am J Respir Crit Care Med ; 203(5): 604-613, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32941735

RESUMO

Rationale: Pneumococcal colonization is key to the pathogenesis of invasive disease but is also immunogenic in young adults, protecting against recolonization. Colonization is rarely detected in older adults, despite high rates of pneumococcal disease.Objectives: To establish experimental human pneumococcal colonization in healthy adults aged 50-84 years, to measure the immune response to pneumococcal challenge, and to assess the protective effect of prior colonization against autologous strain rechallenge.Methods: Sixty-four participants were inoculated with Streptococcus pneumoniae (serotype 6B; 80,000 cfu in each nostril). Colonization was determined by bacterial culture of nasal wash, and humoral immune responses were assessed by anticapsular and antiprotein IgG concentrations.Measurements and Main Results: Experimental colonization was established in 39% of participants (25/64) with no adverse events. Colonization occurred in 47% (9/19) of participants aged 50-59 compared with 21% (3/14) in those aged ≥70 years. Previous pneumococcal polysaccharide vaccination did not protect against colonization. Colonization did not confer serotype-specific immune boosting, with a geometric mean titer (95% confidence interval) of 2.7 µg/ml (1.9-3.8) before the challenge versus 3.0 (1.9-4.7) 4 weeks after colonization (P = 0.53). Furthermore, pneumococcal challenge without colonization led to a drop in specific antibody concentrations from 2.8 µg/ml (2.0-3.9) to 2.2 µg/ml (1.6-3.0) after the challenge (P = 0.006). Antiprotein antibody concentrations increased after successful colonization. Rechallenge with the same strain after a median of 8.5 months (interquartile range, 6.7-10.1) led to recolonization in 5/16 (31%).Conclusions: In older adults, experimental pneumococcal colonization is feasible and safe but demonstrates different immunological outcomes compared with younger adults in previous studies.


Assuntos
Anticorpos Antibacterianos/imunologia , Portador Sadio/imunologia , Infecções Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Infecções Assintomáticas , Técnicas de Cultura , Estudos de Viabilidade , Feminino , Humanos , Imunidade Humoral/imunologia , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Cavidade Nasal , Líquido da Lavagem Nasal , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/uso terapêutico
10.
BMC Health Serv Res ; 22(1): 613, 2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35524209

RESUMO

Sepsis causes 20% of global deaths, particularly among children and vulnerable populations living in developing countries. This study investigated how sepsis is prioritised in Malawi's health system to inform health policy. In this mixed-methods study, twenty multisectoral stakeholders were qualitatively interviewed and asked to quantitatively rate the likelihood of sepsis-related medium-term policy outcomes being realised. Respondents indicated that sepsis is not prioritised in Malawi due to a lack of local sepsis-related evidence and policies. However, they highlighted strong linkages between sepsis and maternal health, antimicrobial resistance and COVID-19, which are already existing national priorities, and offers opportunities for sepsis researchers as policy entrepreneurs. To address the burden of sepsis, we recommend that funding should be channelled to the generation of local evidence, evidence uptake, procurement of resources and treatment of sepsis cases, development of appropriate indicators for sepsis, adherence to infection prevention and control measures, and antimicrobial stewardship.


Assuntos
COVID-19 , Sepse , Antibacterianos/uso terapêutico , COVID-19/epidemiologia , Criança , Farmacorresistência Bacteriana , Feminino , Saúde Global , Humanos , Malaui/epidemiologia , Sepse/tratamento farmacológico , Sepse/epidemiologia
11.
Thorax ; 76(4): 387-395, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33443228

RESUMO

BACKGROUND: Mitigating the socioeconomic impact of tuberculosis (TB) is key to the WHO End TB Strategy. However, little known about socioeconomic well-being beyond TB-treatment completion. In this mixed-methods study, we describe socioeconomic outcomes after TB-disease in urban Blantyre, Malawi, and explore pathways and barriers to financial recovery. METHODS: Adults ≥15 years successfully completing treatment for a first episode of pulmonary TB under the National TB Control Programme were prospectively followed up for 12 months. Socioeconomic, income, occupation, health seeking and cost data were collected. Determinants and impacts of ongoing financial hardship were explored through illness narrative interviews with purposively selected participants. RESULTS: 405 participants were recruited from February 2016 to April 2017. Median age was 35 years (IQR: 28-41), 67.9% (275/405) were male, and 60.6% (244/405) were HIV-positive. Employment and incomes were lowest at TB-treatment completion, with limited recovery in the following year: fewer people were in paid work (63.0% (232/368) vs 72.4% (293/405), p=0.006), median incomes were lower (US$44.13 (IQR: US$0-US$106.15) vs US$72.20 (IQR: US$26.71-US$173.29), p<0.001), and more patients were living in poverty (earning

Assuntos
Emprego/estatística & dados numéricos , Renda/estatística & dados numéricos , Áreas de Pobreza , Tuberculose Pulmonar/epidemiologia , Adulto , Feminino , Humanos , Malaui/epidemiologia , Masculino , Ocupações , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Estudos Prospectivos , Fatores Socioeconômicos
12.
Am J Respir Crit Care Med ; 201(3): 335-347, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31626559

RESUMO

Rationale: Pneumococcal pneumonia remains a global health problem. Colonization of the nasopharynx with Streptococcus pneumoniae (Spn), although a prerequisite of infection, is the main source of exposure and immunological boosting in children and adults. However, our knowledge of how nasal colonization impacts on the lung cells, especially on the predominant alveolar macrophage (AM) population, is limited.Objectives: Using a controlled human infection model to achieve nasal colonization with 6B serotype, we investigated the effect of Spn colonization on lung cells.Methods: We collected BAL from healthy pneumococcal-challenged participants aged 18-49 years. Confocal microscopy and molecular and classical microbiology were used to investigate microaspiration and pneumococcal presence in the lower airways. AM opsonophagocytic capacity was assessed by functional assays in vitro, whereas flow cytometry and transcriptomic analysis were used to assess further changes on the lung cellular populations.Measurements and Main Results: AMs from Spn-colonized individuals exhibited increased opsonophagocytosis to pneumococcus (11.4% median increase) for approximately 3 months after experimental pneumococcal colonization. AMs also had increased responses against other bacterial pathogens. Pneumococcal DNA detected in the BAL samples of Spn-colonized individuals were positively correlated with nasal pneumococcal density (r = 0.71; P = 0.029). Similarly, AM-heightened opsonophagocytic capacity was correlated with nasopharyngeal pneumococcal density (r = 0.61, P = 0.025).Conclusions: Our findings demonstrate that nasal colonization with pneumococcus and microaspiration prime AMs, leading to brisker responsiveness to both pneumococcus and unrelated bacterial pathogens. The relative abundance of AMs in the alveolar spaces, alongside their potential for nonspecific protection, render them an attractive target for novel vaccines.


Assuntos
Macrófagos Alveolares/imunologia , Nasofaringe/microbiologia , Nariz/microbiologia , Streptococcus pneumoniae/isolamento & purificação , Adolescente , Adulto , Bactérias/imunologia , Humanos , Pessoa de Meia-Idade , Aspiração Respiratória , Adulto Jovem
13.
Clin Infect Dis ; 71(10): 2547-2552, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31725849

RESUMO

BACKGROUND: Sepsis is an important cause of mortality globally, although population incidence estimates from low-income settings, including sub-Saharan Africa, are absent. We aimed to estimate sepsis incidence burden using routinely available data from a large urban hospital in Malawi. METHODS: We linked routine-care databases at Queen Elizabeth Central Hospital, Blantyre, Malawi, to provide admission and discharge data for 217 149 adults from 2013-2016. Using a definition of sepsis based on systemic inflammatory response syndrome criteria and Blantyre census population data, we calculated population incidence estimates of sepsis and severe sepsis and used negative binomial regression to assess for trends over time. Missing data were multiply imputed with chained equations. RESULTS: We estimate that the incidence rate of emergency department-attending sepsis and severe sepsis in adults was 1772 per 100 000 person-years (95% confidence interval [CI], 1754-1789) and 303 per 100 000 person-years (95% CI, 295-310), respectively, between 2013 and 2016, with a year-on-year decrease in incidence. In-hospital mortality for patients admitted to the hospital with sepsis and severe sepsis was 23.7% (95% CI, 22.7-24.7%) and 28.1% (95% CI, 26.1 - 30.0%), respectively, with no clear change over time. CONCLUSIONS: Sepsis incidence is higher in Blantyre, Malawi, than in high-income settings, from where the majority of sepsis incidence data are derived. Worldwide sepsis burden is likely to be underestimated, and data from low-income countries are needed to inform the public health response.


Assuntos
Sepse , Adulto , Mortalidade Hospitalar , Hospitais , Humanos , Incidência , Malaui/epidemiologia , Sepse/epidemiologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-33077666

RESUMO

Cefepime-enmetazobactam is a novel ß-lactam-ß-lactamase inhibitor combination with broad-spectrum antimicrobial activity against a range of multidrug-resistant Enterobacteriaceae This agent is being developed for a range of serious hospital infections. An understanding of the extent of partitioning of ß-lactam-ß-lactamase inhibitor combinations into the human lung is required to better understand the potential role of cefepime-enmetazobactam for the treatment of nosocomial pneumonia. A total of 20 healthy volunteers were used to study the intrapulmonary pharmacokinetics of a regimen of 2 g cefepime-1 g enmetazobactam every 8 h intravenously (2 g/1 g q8h i.v.). Each volunteer contributed multiple plasma samples and a single epithelial lining fluid (ELF) sample, obtained by bronchoalveolar lavage. Concentrations of cefepime and enmetazobactam were quantified using liquid chromatography-tandem mass spectrometry. The pharmacokinetic data were modeled using a population methodology, and Monte Carlo simulations were performed to assess the attainment of pharmacodynamic targets defined in preclinical models. The concentration-time profiles of both agents in plasma and ELF were similar. The mean ± standard deviation percentage of partitioning of total drug concentrations of cefepime and enmetazobactam between plasma and ELF was 60.59% ± 28.62% and 53.03% ± 21.05%, respectively. Using pharmacodynamic targets for cefepime of greater than the MIC and free enmetazobactam concentrations of >2 mg/liter in ELF of 20% of the dosing interval, a regimen of cefepime-enmetazobactam of 2 g/0.5 g q8h i.v. infused over 2 h resulted in a probability of target attainment of ≥90% for Enterobacteriaceae with cefepime-enmetazobactam MICs of ≤8 mg/liter. This result provides a rationale to further consider cefepime-enmetazobactam for the treatment of nosocomial pneumonia caused by multidrug-resistant Enterobacteriaceae.


Assuntos
Infecção Hospitalar , Pneumonia Associada a Assistência à Saúde , Antibacterianos/uso terapêutico , Compostos Azabicíclicos , Cefepima , Cefalosporinas , Infecção Hospitalar/tratamento farmacológico , Pneumonia Associada a Assistência à Saúde/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Método de Monte Carlo , Triazóis
15.
Thorax ; 75(3): 269-278, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32102951

RESUMO

BACKGROUND: Post-tuberculosis lung damage (PTLD) is a recognised consequence of pulmonary TB (pTB). However, little is known about its prevalence, patterns and associated outcomes, especially in sub-Saharan Africa and HIV-positive adults. METHODS: Adult (≥15 years) survivors of a first episode of pTB in Blantyre, Malawi, completed the St George's Respiratory Questionnaire, 6-minute walk test, spirometry and high-resolution CT (HRCT) chest imaging at TB treatment completion. Symptom, spirometry, health seeking, TB-retreatment and mortality data were collected prospectively to 1 year. Risk factors for persistent symptoms, pulmonary function decline and respiratory-related health-seeking were identified through multivariable regression modelling. RESULTS: Between February 2016 and April 2017, 405 participants were recruited. Median age was 35 years (IQR: 28 to 41), 77.3% (313/405) had had microbiologically proven pTB, and 60.3% (244/403) were HIV-positive. At pTB treatment completion, 60.7% (246/405) reported respiratory symptoms, 34.2% (125/365) had abnormal spirometry, 44.2% (170/385) had bronchiectasis ≥1 lobe and 9.4% (36/385) had ≥1 destroyed lobe on HRCT imaging. At 1 year, 30.7% (113/368) reported respiratory symptoms, 19.3% (59/305) and 14.1% (43/305) of patients had experienced declines in FEV1 or FVC of ≥100 mL, 16.3% (62/380) had reported ≥1 acute respiratory event and 12.2% (45/368) had symptoms affecting their ability to work. CONCLUSIONS: PTLD is a common and under-recognised consequence of pTB that is disabling for patients and associated with adverse outcomes beyond pTB treatment completion. Increased efforts to prevent PTLD and guidelines for management of established disease are urgently needed. Low-cost clinical interventions to improve patient outcomes must be evaluated.


Assuntos
Bronquiectasia/epidemiologia , Infecções por HIV/epidemiologia , Lesão Pulmonar/epidemiologia , Lesão Pulmonar/fisiopatologia , Tuberculose Pulmonar/complicações , Adulto , Bronquiectasia/diagnóstico por imagem , Bronquiectasia/microbiologia , Doença Crônica , Coinfecção/epidemiologia , Tosse/epidemiologia , Tosse/microbiologia , Dispneia/epidemiologia , Dispneia/microbiologia , Cuidado Periódico , Feminino , Volume Expiratório Forçado , Inquéritos Epidemiológicos , Humanos , Lesão Pulmonar/diagnóstico por imagem , Lesão Pulmonar/microbiologia , Malaui/epidemiologia , Masculino , Prevalência , Estudos Prospectivos , Radiografia Torácica , Recuperação de Função Fisiológica , Espirometria , Exacerbação dos Sintomas , Fatores de Tempo , Tomografia Computadorizada por Raios X , Tuberculose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/fisiopatologia , Capacidade Vital , Teste de Caminhada , Adulto Jovem
16.
Trop Med Int Health ; 25(5): 590-599, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31989731

RESUMO

OBJECTIVE: To describe the features of HIV-associated chronic lung disease (CLD) in older children and adolescents living with HIV and to examine the clinical factors associated with CLD. This is a post hoc analysis of baseline data from the BREATHE clinical trial (ClinicalTrials.gov, NCT02426112). METHODS: Children and adolescents aged 6-19 years were screened for CLD (defined as a FEV1 z-score <-1 with no reversibility post-bronchodilation with salbutamol) at two HIV clinics in Harare, Zimbabwe, and Blantyre, Malawi. Eligible participants with CLD (cases) were enrolled, together with a control group without CLD [frequency-matched by age group and duration on antiretroviral therapy (ART)] in a 4:1 allocation ratio. A clinical history and examination were undertaken. The association between CLD and a priori-defined demographic and clinical covariates was investigated using multivariable logistic regression. RESULTS: Of the 1585 participants screened, 419 (32%) had a FEV1 z-score <-1, of whom 347 were enrolled as cases [median age 15.3 years (IQR 12.7-17.7); 48.9% female] and 74 with FEV1 z-score >0 as controls [median age 15.6 years (IQR 12.1-18.2); 62.2% female]. Among cases, current respiratory symptoms including cough and shortness of breath were reported infrequently (9.3% and 1.8%, respectively). However, 152 (43.8%) of cases had a respiratory rate above the 90th centile for their age. Wasting and taking second-line ART were independently associated with CLD. CONCLUSIONS: The presence of CLD indicates the need to address additional treatment support for youth living with HIV, alongside ART provision, to ensure a healthier adulthood.


OBJECTIF: Décrire les caractéristiques de la maladie pulmonaire chronique (MPC) associée au VIH chez les enfants plus âgés et les adolescents vivant avec le VIH et examiner les facteurs cliniques associés à la MPC. Il s'agit d'une analyse post-hoc des données de référence de l'essai clinique BREATHE (ClinicalTrials.gov, NCT02426112 ). MÉTHODES: Les enfants et adolescents âgés de 6 à 19 ans ont été dépistés pour la MPC (défini comme un score z FEV1 <-1 sans réversibilité post-bronchodilatation avec du salbutamol) dans deux cliniques VIH à Harare, au Zimbabwe et à Blantyre, au Malawi. Les participants éligibles atteints de MPC (cas) ont été inscrits, ainsi qu'un groupe témoin sans MPC (fréquence appariée par groupe d'âge et durée sous ART) dans un rapport d'allocation de 4:1. Une histoire clinique et un examen ont été entrepris. L'association entre la MPC et les covariables démographiques et cliniques définies a priori a été étudiée en utilisant une régression logistique multivariable. RÉSULTATS: Sur les 1.585 participants dépistés, 419 (32%) avaient un score z FEV 1 <-1, dont 347 étaient inscrits comme cas (âge médian 15,3 ans [IQR 12,7 -17,7]; 48,9% de sexe féminin), et 74 avec un score z FEV1 >0 comme témoins (âge médian 15,6 ans [IQR 12,1 -18,2]; 62,2% de sexe féminin). Parmi les cas, les symptômes respiratoires en cours, y compris la toux et l'essoufflement, n'ont pas été rapportés fréquemment (9,3% et 1,8%, respectivement). Cependant, 152 (43,8%) des cas avaient une fréquence respiratoire supérieure au 90e centile pour leur âge. L'émaciation et la prise d'un traitement antirétroviral (ART) de deuxième intention étaient indépendamment associées à la MPC. CONCLUSIONS: La présence de MPC indique la nécessité d'un soutien thérapeutique supplémentaire aux jeunes vivant avec le VIH, à côté de à la fourniture de l'ART, pour assurer un âge adulte en meilleure santé.


Assuntos
Infecções por HIV , HIV-1 , Pneumopatias/epidemiologia , Adolescente , Estudos de Casos e Controles , Criança , Serviços de Saúde da Criança , Feminino , Humanos , Pneumopatias/complicações , Malaui/epidemiologia , Masculino , Inquéritos e Questionários , Sobreviventes , Adulto Jovem , Zimbábue/epidemiologia
17.
Crit Care ; 24(1): 286, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503647

RESUMO

BACKGROUND: Sepsis guidelines are widely used in high-income countries and intravenous fluids are an important supportive treatment modality. However, fluids have been harmful in intervention trials in low-income countries, most notably in sub-Saharan Africa. We assessed the relevance, quality and applicability of available guidelines for the fluid management of adult patients with sepsis in this region. METHODS: We identified sepsis guidelines by systematic review with broad search terms, duplicate screening and data extraction. We included peer-reviewed publications with explicit relevance to sepsis and fluid therapy. We excluded those designed exclusively for specific aetiologies of sepsis, for limited geographic locations, or for non-adult populations. We used the AGREE II tool to assess the quality of guideline development, performed a narrative synthesis and used theoretical case scenarios to assess practical applicability to everyday clinical practice in resource-constrained settings. RESULTS: Published sepsis guidelines are heterogeneous in sepsis definition and in quality: 8/10 guidelines had significant deficits in applicability, particularly with reference to resource considerations in low-income settings. Indications for intravenous fluid were hypotension (8/10), clinical markers of hypoperfusion (6/10) and lactataemia (3/10). Crystalloids were overwhelmingly recommended (9/10). Suggested volumes varied; 5/10 explicitly recommended "fluid challenges" with reassessment, totalling between 1 L and 4 L during initial resuscitation. Fluid balance, including later de-escalation of therapy, was not specifically described in any. Norepinephrine was the preferred initial vasopressor (5/10), specifically targeted to MAP > 65 mmHg (3/10), with higher values suggested in pre-existing hypertension (1/10). Recommendations for guidelines were almost universally derived from evidence in high-income countries. None of the guidelines suggested any refinement for patients with malnutrition. CONCLUSIONS: Widely used international guidelines contain disparate recommendations on intravenous fluid use, lack specificity and are largely unattainable in low-income countries given available resources. A relative lack of high-quality evidence from sub-Saharan Africa increases reliance on recommendations which may not be relevant or implementable.


Assuntos
Hidratação/normas , Guias como Assunto/normas , Sepse/terapia , África Subsaariana , Hidratação/métodos , Humanos , Qualidade da Assistência à Saúde/normas
18.
BMC Med Ethics ; 21(1): 14, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024497

RESUMO

BACKGROUND: Human infection studies (HIS) are valuable in vaccine development. Deliberate infection, however, creates challenging questions, particularly in low and middle-income countries (LMICs) where HIS are new and ethical challenges may be heightened. Consultation with stakeholders is needed to support contextually appropriate and acceptable study design. We examined stakeholder perceptions about the acceptability and ethics of HIS in Malawi, to inform decisions about planned pneumococcal challenge research and wider understanding of HIS ethics in LMICs. METHODS: We conducted 6 deliberative focus groups and 15 follow-up interviews with research staff, medical students, and community representatives from rural and urban Blantyre. We also conducted 5 key informant interviews with clinicians, ethics committee members, and district health government officials. RESULTS: Stakeholders perceived HIS research to have potential population health benefits, but they also had concerns, particularly related to the safety of volunteers and negative community reactions. Acceptability depended on a range of conditions related to procedures for voluntary and informed consent, inclusion criteria, medical care or support, compensation, regulation, and robust community engagement. These conditions largely mirror those in existing guidelines for HIS and biomedical research in LMICs. Stakeholder perceptions pointed to potential tensions, for example, balancing equity, safety, and relevance in inclusion criteria. CONCLUSIONS: Our findings suggest HIS research could be acceptable in Malawi, provided certain conditions are in place. Ongoing assessment of participant experiences and stakeholder perceptions will be required to strengthen HIS research during development and roll-out.


Assuntos
Atitude do Pessoal de Saúde , Pesquisa Biomédica/ética , Consentimento Livre e Esclarecido/ética , Vacinas Pneumocócicas/administração & dosagem , Pneumonia Pneumocócica/prevenção & controle , Países em Desenvolvimento , Grupos Focais , Humanos , Entrevistas como Assunto , Malaui , Projetos de Pesquisa
19.
J Infect Dis ; 219(12): 1989-1993, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-30690468

RESUMO

Pneumococcal colonization is rarely studied in adults, except as part of family surveys. We report the outcomes of colonization screening in healthy adults (all were nonsmokers without major comorbidities or contact with children aged <5 years) who had volunteered to take part in clinical research. Using nasal wash culture, we detected colonization in 6.5% of volunteers (52 of 795). Serotype 3 was the commonest serotype (10 of 52 isolates). The majority of the remaining serotypes (35 of 52 isolates) were nonvaccine serotypes, but we also identified persistent circulation of serotypes 19A and 19F. Resistance to at least 1 of 6 antibiotics tested was found in 8 of 52 isolates.


Assuntos
Infecções Pneumocócicas/imunologia , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Vacinas Conjugadas/imunologia , Adulto , Antibacterianos/imunologia , Farmacorresistência Bacteriana/imunologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Sorogrupo , Reino Unido , Adulto Jovem
20.
Clin Infect Dis ; 69(4): 580-587, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30828710

RESUMO

BACKGROUND: Older children and adolescents with perinatally acquired human immunodeficiency virus (PHIV) infection in Africa experience multiple comorbidities that are not typical of HIV-associated opportunistic infections, including growth impairment and chronic lung disease. We examined associations between plasma cytomegalovirus (CMV) DNA and lung function and growth. METHODS: Plasma CMV DNA loads were measured children aged 6-16 years with PHIV (n = 402) and HIV-uninfected controls (n = 224). The HIV-infected children were either newly diagnosed or known HIV infected and stable on antiretroviral therapy (ART) for >6 months. CMV DNA loads were measured using quantitative polymerase chain reaction. CMV DNAemia was modeled as a time-varying outcome using longitudinal mixed-effects logistic regression. RESULTS: At enrollment, CMV DNAemia ≥1000 copies/mL (defined as "clinically significant") was detected in 5.8% of uninfected children, 14.7% of HIV-infected participants stable on ART, and 22.6% of HIV-infected ART-naive children (χ2 = 23.8, P < .001). The prevalence of CMV DNAemia ≥1000 copies/mL was associated with CD4 counts <350 cells/µL. Among HIV-infected ART-naive children, the presence of CMV DNAemia of ≥1000 copies/mL was independently associated with reduced lung function (adjusted odds ratio [aOR] = 3.23; 95% confidence interval [CI], 1.23-8.46; P = .017). Among ART-treated children, stunting was associated with CMV DNAemia of ≥1000 copies/mL (aOR = 2.79; 95% CI, 0.97-8.02; P = .057). CONCLUSIONS: Clinically significant levels of CMV DNAemia were common in older children with PHIV, even those on ART, suggesting a role for inadequately controlled CMV infection in the pathogenesis of PHIV comorbidities in Africa.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus/genética , DNA Viral/sangue , Infecções por HIV , Adolescente , Contagem de Linfócito CD4 , Criança , Doença Crônica , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/virologia , Feminino , Transtornos do Crescimento , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Transmissão Vertical de Doenças Infecciosas , Pneumopatias/complicações , Pneumopatias/epidemiologia , Pneumopatias/virologia , Masculino , Prevalência , Estudos Prospectivos
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