Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
1.
Clin Infect Dis ; 78(2): 457-460, 2024 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-37897407

RESUMO

Cerebral malaria is an important cause of mortality and neurodisability in endemic regions. We show magnetic resonance imaging (MRI) features suggestive of cytotoxic and vasogenic cerebral edema followed by microhemorrhages in 2 adult UK cases, comparing them with an Indian cohort. Long-term follow-up images correlate ongoing changes with residual functional impairment.


Assuntos
Edema Encefálico , Malária Cerebral , Adulto , Humanos , Malária Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Edema Encefálico/etiologia , Edema Encefálico/patologia
2.
Sci Rep ; 13(1): 22998, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-38155156

RESUMO

Durgama Anchalare Malaria Nirakaran (DAMaN) is a multi-component malaria intervention for hard-to-reach villages in Odisha, India. The main component, malaria camps (MCs), consists of mass screening, treatment, education, and intensified vector control. We evaluated MC effectiveness using a quasi-experimental cluster-assigned stepped-wedge study with a pretest-posttest control group in 15 villages: six immediate (Arm A), six delayed (Arm B), and three previous interventions (Arm C). The primary outcome was PCR + Plasmodium infection prevalence. The time (i.e., baseline vs. follow-up 3) x study arm interaction term shows that there were statistically significant lower odds of PCR + Plasmodium infection in Arm A (AOR = 0.36, 95% CI = 0.17, 0.74) but not Arm C as compared to Arm B at the third follow-up. The cost per person ranged between US$3-8, the cost per tested US$4-9, and the cost per treated US$82-1,614, per camp round. These results suggest that the DAMaN intervention is a promising and financially feasible approach for malaria control.


Assuntos
Malária , Humanos , Índia/epidemiologia , Malária/epidemiologia , Malária/prevenção & controle , Malária/diagnóstico , Programas de Rastreamento , Prevalência
3.
Pathogens ; 12(4)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37111408

RESUMO

No specific or adjunctive therapies exist to treat cerebral malaria (CM) as of date. CM is a neuropathological manifestation of the malaria infection in humans, caused by the hemoparasitic pathogen Plasmodium falciparum. Driven through a multitude of virulence factors, varied immune responses, variations in brain swelling with regard to the age of patients, parasite biomass, and parasite-typing, the essential pathogenetic mechanisms underlying clinical CM have remained elusive. However, a recent series of studies based on molecular, immunologic, and advanced neuroradiologic and machine-learning approaches have unraveled new trends and insights to better understand and focus on the key determinants of CM in humans. This could possibly be the beginning of the design of new and effective adjunctive therapies that may not be common or applicable to the entire malarious world, but that could, rather, be specific to the variations in the determinants of CM.

4.
medRxiv ; 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36711482

RESUMO

Durgama Anchalare Malaria Nirakaran (DAMaN) is a multi-component malaria intervention for hard-to-reach villages in Odisha, India. The main component, Malaria Camps (MCs), consists of mass screening, treatment, education, and intensified vector control. We evaluated MC effectiveness using a quasi-experimental cluster-assigned stepped-wedge study with a pretest-posttest control group in 15 villages: six immediate (Arm A), six delayed (Arm B), and three previous interventions (Arm C). The primary outcome was PCR+ Plasmodium infection prevalence. Across all arms, the odds of PCR+ malaria were 54% lower at the third follow-up compared to baseline. A time (i.e., visit) x study arm interaction revealed significantly lower odds of PCR+ malaria in Arm A versus B at the third follow-up. The cost per person ranged between US$3-8, the cost per tested US$4-7, and the cost per treated US$82-1,614, per camp round. These results suggest that the DAMaN intervention is a promising, financially feasible approach for malaria control.

5.
Am J Trop Med Hyg ; 107(4_Suppl): 97-106, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36228919

RESUMO

The Center for the Study of Complex Malaria in India (CSCMi) is one of 10 International Centers of Excellence in Malaria Research funded by the National Institutes of Health since 2010. The Center combines innovative research with capacity building and technology transfer to undertake studies with clinical and translational impact that will move malaria control in India toward the ultimate goal of malaria elimination/eradication. A key element of each research site in the four states of India (Tamil Nadu, Gujarat, Odisha, and Meghalaya) has been undertaking community- and clinic-based epidemiology projects to characterize the burden of malaria in the region. Demographic and clinical data and samples collected during these studies have been used in downstream projects on, for example, the widespread use of mosquito repellants, the population genomics of Plasmodium vivax, and the serological responses to P. vivax and Plasmodium falciparum antigens that reflect past or present exposure. A focus has been studying the pathogenesis of severe malaria caused by P. falciparum through magnetic resonance imaging of cerebral malaria patients. Here we provide a snapshot of some of the basic and applied research the CSCMi has undertaken over the past 12 years and indicate the further research and/or clinical and translational impact these studies have had.


Assuntos
Malária Falciparum , Malária Vivax , Malária , Animais , Humanos , Índia/epidemiologia , Malária/epidemiologia , Malária/prevenção & controle , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Malária Vivax/epidemiologia , Plasmodium falciparum/genética , Plasmodium vivax/genética , Pesquisa Translacional Biomédica
6.
Am J Trop Med Hyg ; 107(4_Suppl): 90-96, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36228922

RESUMO

The Center for the Study of Complex Malaria in India (CSCMi) was launched in 2010 with the overall goal of addressing major gaps in our understanding of "complex malaria" in India through projects on the epidemiology, transmission, and pathogenesis of the disease. The Center was mandated to adopt an integrated approach to malaria research, including building capacity, developing infrastructure, and nurturing future malaria leaders while conducting relevant and impactful studies to assist India as it moves from control to elimination. Here, we will outline some of the interactions and impacts the Center has had with malaria policy and control counterparts in India, as well as describe emerging needs and new research questions that have become apparent over the past 12 years.


Assuntos
Malária , Humanos , Índia/epidemiologia , Malária/epidemiologia , Malária/prevenção & controle
7.
Life Sci Alliance ; 5(6)2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35260473

RESUMO

Brain swelling occurs in cerebral malaria (CM) and may either reverse or result in fatal outcome. It is currently unknown how brain swelling in CM reverses, as brain swelling at the acute stage is difficult to study in humans and animal models with reliable induction of reversible edema are not known. In this study, we show that reversible brain swelling in experimental murine CM can be induced reliably after single vaccination with radiation-attenuated sporozoites as proven by in vivo high-field magnetic resonance imaging. Our results provide evidence that brain swelling results from transcellular blood-brain barrier disruption (BBBD), as revealed by electron microscopy. This mechanism enables reversal of brain swelling but does not prevent persistent focal brain damage, evidenced by microhemorrhages, in areas of most severe BBBD. In adult CM patients magnetic resonance imaging demonstrate microhemorrhages in more than one third of patients with reversible edema, emphasizing similarities of the experimental model and human disease. Our data suggest that targeting transcellular BBBD may represent a promising adjunct therapeutic approach to reduce edema and may improve neurological outcome.


Assuntos
Edema Encefálico , Malária Cerebral , Animais , Barreira Hematoencefálica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/etiologia , Edema Encefálico/patologia , Edema/patologia , Humanos , Malária Cerebral/patologia , Camundongos
8.
Minim Invasive Surg ; 2022: 6781544, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35223097

RESUMO

INTRODUCTION: Single incision laparoscopic surgery (SILS) is accepted as a safe alternative to conventional multiport laparoscopic (MPL) cholecystectomy for benign gallbladder disease. Since many surgeons carefully select patients without inflammation, there are limited data on SILS for acute cholecystitis. We report a single surgeon experience with SILS cholecystectomy for patients with acute cholecystitis. MATERIALS AND METHODS: After securing ethical approval, we performed an audit of all SILS cholecystectomies for acute cholecystitis by a single surgeon from January 1, 2009, to December 31, 2019. The following data were extracted: patient demographics, intraoperative details, surgical techniques, specialized equipment utilized, conversions (additional port placement), morbidity, and mortality. Data were analyzed using SPSS 12.0. RESULTS: SILS cholecystectomy was performed in 25 females at a mean age of 35 ± 4.1 (SD) years and a mean BMI of 31.9 ± 3.8 (SD) using a direct fascial puncture technique without access platforms. The operations were completed in 83 ± 29.4 minutes (mean ± SD) with an estimated blood loss of 76.9 ± 105 (mean + SD). Three (12%) patients required additional 5 mm port placement (conversions), but no open operations were performed. The patients were hospitalized for 1.96 ± 0.9 days (mean ± SD). There were 2 complications: postoperative superficial SSI (grade I) and a diaphragmatic laceration (grade III). No bile duct injuries were reported. There were 9 patients with complicated acute cholecystitis, and this sub-group had longer mean operating times (109.2 ± 27.3 minutes) and mean postoperative hospital stay (1.3 ± 0.87 days). CONCLUSION: The SILS technique is a feasible and safe approach to perform cholecystectomy for acute cholecystitis. We advocate a low threshold to place additional ports to assist with difficult dissections for patient safety.

9.
Clin Infect Dis ; 75(1): 11-18, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34905777

RESUMO

BACKGROUND: Cerebral malaria in adults is associated with brain hypoxic changes on magnetic resonance (MR) images and has a high fatality rate. Findings of neuroimaging studies suggest that brain involvement also occurs in patients with uncomplicated malaria (UM) or severe noncerebral malaria (SNCM) without coma, but such features were never rigorously characterized. METHODS: Twenty patients with UM and 21 with SNCM underwent MR imaging on admission and 44-72 hours later, as well as plasma analysis. Apparent diffusion coefficient (ADC) maps were generated, with values from 5 healthy individuals serving as controls. RESULTS: Patients with SNCM had a wide spectrum of cerebral ADC values, including both decreased and increased values compared with controls. Patients with low ADC values, indicating cytotoxic edema, showed hypoxic patterns similar to cerebral malaria despite the absence of deep coma. Conversely, high ADC values, indicative of mild vasogenic edema, were observed in both patients with SNCM and patients with UM. Brain involvement was confirmed by elevated circulating levels of S100B. Creatinine was negatively correlated with ADC in SNCM, suggesting an association between acute kidney injury and cytotoxic brain changes. CONCLUSIONS: Brain involvement is common in adults with SNCM and a subgroup of hospitalized patients with UM, which warrants closer neurological follow-up. Increased creatinine in SNCM may render the brain more susceptible to cytotoxic edema.


Assuntos
Edema Encefálico , Malária Cerebral , Malária Falciparum , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/etiologia , Edema Encefálico/patologia , Coma/complicações , Creatinina , Humanos , Malária Cerebral/complicações , Malária Falciparum/complicações
10.
JCI Insight ; 6(18)2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34549725

RESUMO

Cerebral malaria (CM) affects children and adults, but brain swelling is more severe in children. To investigate features associated with brain swelling in malaria, we performed blood profiling and brain MRI in a cohort of pediatric and adult patients with CM in Rourkela, India, and compared them with an African pediatric CM cohort in Malawi. We determined that higher plasma Plasmodium falciparum histidine rich protein 2 (PfHRP2) levels and elevated var transcripts that encode for binding to endothelial protein C receptor (EPCR) were linked to CM at both sites. Machine learning models trained on the African pediatric cohort could classify brain swelling in Indian children CM cases but had weaker performance for adult classification, due to overall lower parasite var transcript levels in this age group and more severe thrombocytopenia in Rourkela adults. Subgrouping of patients with CM revealed higher parasite biomass linked to severe thrombocytopenia and higher Group A-EPCR var transcripts in mild thrombocytopenia. Overall, these findings provide evidence that higher parasite biomass and a subset of Group A-EPCR binding variants are common features in children and adult CM cases, despite age differences in brain swelling.


Assuntos
Antígenos de Protozoários/sangue , Edema Encefálico/sangue , Malária Cerebral/complicações , Carga Parasitária , Proteínas de Protozoários/sangue , Proteínas de Protozoários/genética , Trombocitopenia/sangue , Adolescente , Adulto , Fatores Etários , Idoso , Biomarcadores/sangue , Edema Encefálico/classificação , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/parasitologia , Criança , Pré-Escolar , Receptor de Proteína C Endotelial/metabolismo , Humanos , Índia , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Malaui , Pessoa de Meia-Idade , Gravidade do Paciente , Proteínas de Protozoários/metabolismo , Trombocitopenia/parasitologia , Transcrição Gênica , Adulto Jovem
12.
Glob Health Action ; 14(1): 1886458, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33866961

RESUMO

The Indian state of Odisha has a longstanding battle with forest malaria. Many remote and rural villages have poor access to health care, a problem that is exacerbated during the rainy season when malaria transmission is at its peak. Approximately 62% of the rural population consists of tribal groups who are among the communities most negatively impacted by malaria. To address the persistently high rates of malaria in these remote regions, the Odisha State Malaria Control Program introduced 'malaria camps' in 2017 where teams of health workers visit villages to educate the population, enhance vector control methods, and perform village-wide screening and treatment. Malaria rates declined statewide, particularly in forested areas, following the introduction of the malaria camps, but the impact of the intervention is yet to be externally evaluated. This study protocol describes a cluster-assigned quasi-experimental stepped-wedge study with a pretest-posttest control group design that evaluates if malaria camps reduce the prevalence of malaria, compared to control villages which receive the usual malaria control interventions (e.g. IRS, ITNs), as detected by PCR.


Assuntos
Malária , Humanos , Índia/epidemiologia , Malária/tratamento farmacológico , Malária/epidemiologia , Malária/prevenção & controle , Reação em Cadeia da Polimerase , Prevalência , População Rural
13.
Clin Infect Dis ; 73(7): e2387-e2396, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33321516

RESUMO

BACKGROUND: Cerebral malaria is a common presentation of severe Plasmodium falciparum infection and remains an important cause of death in the tropics. Key aspects of its pathogenesis are still incompletely understood, but severe brain swelling identified by magnetic resonance imaging (MRI) was associated with a fatal outcome in African children. In contrast, neuroimaging investigations failed to identify cerebral features associated with fatality in Asian adults. METHODS: Quantitative MRI with brain volume assessment and apparent diffusion coefficient (ADC) histogram analyses were performed for the first time in 65 patients with cerebral malaria to compare disease signatures between children and adults from the same cohort, as well as between fatal and nonfatal cases. RESULTS: We found an age-dependent decrease in brain swelling during acute cerebral malaria, and brain volumes did not differ between fatal and nonfatal cases across both age groups. In nonfatal disease, reversible, hypoxia-induced cytotoxic edema occurred predominantly in the white matter in children, and in the basal ganglia in adults. In fatal cases, quantitative ADC histogram analyses also demonstrated different end-stage patterns between adults and children: Severe hypoxia, evidenced by global ADC decrease and elevated plasma levels of lipocalin-2 and microRNA-150, was associated with a fatal outcome in adults. In fatal pediatric disease, our results corroborate an increase in brain volume, leading to augmented cerebral pressure, brainstem herniation, and death. CONCLUSIONS: Our findings suggest distinct pathogenic patterns in pediatric and adult cerebral malaria with a stronger cytotoxic component in adults, supporting the development of age-specific adjunct therapies.


Assuntos
Encefalopatias , Malária Cerebral , Malária Falciparum , Adulto , Encéfalo/diagnóstico por imagem , Encefalopatias/diagnóstico por imagem , Encefalopatias/parasitologia , Criança , Humanos , Lipocalina-2/sangue , Imageamento por Ressonância Magnética , Malária Cerebral/diagnóstico por imagem , Malária Falciparum/diagnóstico por imagem , MicroRNAs/sangue
14.
Cureus ; 12(10): e11126, 2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33240719

RESUMO

Objective Removal of a gallbladder remnant occasionally becomes necessary when retained stones become symptomatic. Although the laparoscopic approach has been described, it is not yet considered the standard of care. We sought to determine the outcomes after completion cholecystectomies in the resource-poor setting within the Caribbean.  Methods We carried out an audit of the databases from all hepatobiliary surgeons in the Anglophone Caribbean. We identified all patients who had completion cholecystectomy over the five-year period from July 1, 2012 to June 30, 2018. Retrospective chart review was performed to extract the following data: patient demographics, diagnoses, presenting complaints, operative details, morbidity, mortality, and clinical outcomes. Descriptive statistics were generated using Statistical Packaging for Social Sciences (SPSS), version 12.0 (SPSS Inc., Chicago IL) Results There were 12 patients who were subjected to laparoscopic completion cholecystectomy for acute cholecystitis (7), severe biliary pancreatitis (3), and chronic cholecystitis (2) secondary to stones in a gallbladder remnant. There were 10 women and two men at a mean age of 47.4 years (range 32-60; standard deviation (SD) +/-7.81; median 48; mode 52) and a mean body mass index (BMI) of 30.8 Kg/M2 (SD +/-3.81; range 26-38; median 29.5). The mean interval between the index operation and the completion operation was 14.8 months (SD +/- 12.3; range 1-48; median 13; mode 18). Five (42%) patients had their original cholecystectomy using the open approach. Five (42%) index operations were done on an emergent basis and the gallbladder remnant was deliberately left behind in three (25%) index operations. The completion cholecystectomies were all completed laparoscopically in 130.5 minutes (SD +/- 30.5; range 90-180, median 125; mode 125) without any conversions or mortality. There were two minor bile leaks that resolved without intervention through an indwelling drain.  Discussion Completions cholecystectomy can be completed via the laparoscopic approach with good outcomes and acceptable morbidity and mortality rates. The patients derive the same advantages as elective cholecystectomies. Therefore, the laparoscopic approach, when performed by hepatobiliary surgeons with advanced laparoscopic expertise in specialized centers, should be the new standard of care.

15.
Acta Trop ; 211: 105647, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32735794

RESUMO

To characterize malaria and assist in prevention efforts, we conducted a series of epidemiological studies in Sundargarh district, India, as part of an NIH-funded International Center of Excellence for Malaria Research. In a published survey around Rourkela in 2013-2014 (N = 1307), malaria prevalence was found to be 8.3%. Using these data, villages were divided into low (<2%), medium (2-10%) and high (>10%) malaria prevalence, and risk factors assessed by type of village. In the six low malaria villages, four persons were positive by PCR; in the four medium malaria villages, prevalence was 7% (35 infections, 7 P. vivax); and in the three high malaria villages, prevalence was 21% (62 infections, 10 P. vivax and 5 mixed with P. vivax and P. falciparum). A total of 30.6% infections were submicroscopic and 40.6% were asymptomatic. Our analyses showed that the rainy season and male gender were risk factors for malaria; in high malaria villages, young age was an additional risk factor, and indoor and outdoor spraying was protective compared to no spraying. We undertook a subsequent behavioral survey in four of the medium and high malaria villages in 2017 to investigate the behavioral aspects of malaria risk. Among 500 participants in 237 households, adult men (15+ years) were more likely to be outside in the evening (34.5% vs. 7.9% among adult women 15+ years and 0.7% among children, p < 0.001), or to sleep outside (7.5% vs. 0.5% and 0%, respectively, p < 0.001). Although women were more likely to get up before 6 a.m. (86.6%, vs. 70.5% among men, 50.7% among children, p < 0.001), men were more likely to be outside in the early morning (77.6% among men, 11.2% among women, and 11.1% among children, p < 0.001). More children used insecticide treated nets the previous night (73.4%) than men (45.6%) or women (39.6%), and repellents were used by 29.5% of 234 households (insecticide creams were not used at all). Malaria control and elimination in India will need local approaches, and the promotion of repellent cream use by at-risk groups could be further explored in addition to mass-screen or treat programs in high-risk villages.


Assuntos
Repelentes de Insetos/farmacologia , Inseticidas/farmacologia , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Atenção à Saúde , Características da Família , Feminino , Humanos , Índia/epidemiologia , Malária Falciparum/prevenção & controle , Malária Vivax/prevenção & controle , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
16.
J Infect Dis ; 221(2): 285-292, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31504666

RESUMO

BACKGROUND: Liberal fluid resuscitation has proved harmful in adults with severe malaria, but the level of restriction has not been defined. METHODS: In a prospective observational study in adults with severe falciparum malaria, restrictive fluid management was provided at the discretion of the treating physician. The relationships between the volume of fluid and changes in renal function or tissue perfusion were evaluated. RESULTS: A total of 154 patients were studied, 41 (26.6%) of whom died. Median total fluid intake during the first 6 and 24 hours from enrollment was 3.3 (interquartile range [IQR], 1.8-5.1) mL/kg per hour and 2.2 (IQR, 1.6-3.2) mL/kg per hour, respectively. Total fluid intake at 6 hours was not correlated with changes in plasma creatinine at 24 hours (n = 116; rs = 0.16; P = .089) or lactate at 6 hours (n = 94; rs = -0.05; P = .660). Development of hypotensive shock or pulmonary edema within 24 hours after enrollment were not related to the volume of fluid administration. CONCLUSIONS: Restrictive fluid management did not worsen kidney function and tissue perfusion in adult patients with severe falciparum malaria. We suggest crystalloid administration of 2-3 mL/kg per hour during the first 24 hours without bolus therapy, unless the patient is hypotensive.


Assuntos
Hidratação/métodos , Malária Falciparum/tratamento farmacológico , Injúria Renal Aguda/etiologia , Adulto , Feminino , Hidratação/efeitos adversos , Humanos , Testes de Função Renal , Ácido Láctico/sangue , Malária Falciparum/mortalidade , Masculino , Estudos Prospectivos , Edema Pulmonar/etiologia , Adulto Jovem
17.
J Infect Dis ; 221(9): 1518-1527, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-31693130

RESUMO

BACKGROUND: Impaired microvascular perfusion is central to the development of coma and lactic acidosis in severe falciparum malaria. Refractory hypotension is rare on admission but develops frequently in fatal cases. We assessed cardiac function and volume status in severe falciparum malaria and its prognostic significance. METHODS: Patients with severe (N = 101) or acute uncomplicated falciparum malaria (N = 83) were recruited from 2 hospitals in India and Bangladesh, and healthy participants (N = 44) underwent echocardiography. RESULTS: Patients with severe malaria had 38% shorter left ventricular (LV) filling times and 25% shorter LV ejection times than healthy participants because of tachycardia; however, stroke volume, LV internal diameter in diastole (LVIDd), and LV internal diameter in systole (LVIDs) indices were similar. A low endocardial fraction shortening (eFS) was present in 17% (9 of 52) of severe malaria patients. Adjusting for preload and afterload, eFS was similar in health and severe malaria. Fatal cases had smaller baseline LVIDd and LVIDs indices, more collapsible inferior vena cavae (IVC), and higher heart rates than survivors. The LVIDs and IVC collapsibility were independent predictors for mortality, together with base excess and Glasgow Coma Scale. CONCLUSIONS: Patients with severe malaria have rapid ejection of a normal stroke volume. Fatal cases had features of relative hypovolemia and reduced cardiac index reserve.


Assuntos
Hipovolemia/parasitologia , Malária Falciparum/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adulto , Bangladesh , Estudos de Casos e Controles , Ecocardiografia , Feminino , Hemodinâmica , Humanos , Hipovolemia/fisiopatologia , Índia , Modelos Lineares , Modelos Logísticos , Malária Falciparum/diagnóstico por imagem , Malária Falciparum/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Disfunção Ventricular Esquerda/parasitologia , Função Ventricular Esquerda , Adulto Jovem
18.
J Infect Dis ; 221(1): 127-137, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31693729

RESUMO

BACKGROUND: In severe falciparum malaria, unlike sepsis, hypotension on admission is uncommon. We hypothesized that low nitric oxide bioavailability due to the presence of cell-free hemoglobin (CFH) increases vascular tone in severe malaria. METHODS: Patients with severe malaria (n = 119), uncomplicated malaria (n = 91), or suspected bacterial sepsis (n = 56), as well as healthy participants (n = 50), were recruited. The systemic vascular resistance index (SVRI) was estimated from the echocardiographic cardiac index and the mean arterial pressure. RESULTS: SVRI and hematocrit levels were lower and plasma CFH and asymmetric dimethylarginine levels were higher in patients with malaria, compared with healthy participants. In multivariate linear regression models for mean arterial pressure or SVRI in patients with severe malaria, hematocrit and CFH but not asymmetric dimethylarginine were significant predictors. The SVRI was lower in patients with suspected bacterial sepsis than in those with severe malaria, after adjustment for hematocrit and age. Plasma CFH levels correlated positively with the core-peripheral temperature gradient and plasma lactate levels and inversely with the perfusion index. Impaired peripheral perfusion, as reflected by a low perfusion index or a high core-peripheral temperature gradient, predicted mortality in patients with severe malaria. CONCLUSIONS: CFH is associated with mean arterial pressure, SVRI, and peripheral perfusion in patients with severe malaria. This may be mediated through the nitric oxide scavenging potency of CFH, increasing basal vascular tone and impairing tissue perfusion.


Assuntos
Pressão Arterial , Hemoglobinas/metabolismo , Malária Falciparum/fisiopatologia , Fluxo Sanguíneo Regional , Resistência Vascular , Adulto , Arginina/análogos & derivados , Arginina/sangue , Bacteriemia/fisiopatologia , Estudos de Casos e Controles , Ecocardiografia , Feminino , Hematócrito , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico , Gravidade do Paciente , Adulto Jovem
19.
BMC Infect Dis ; 19(1): 572, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31269906

RESUMO

BACKGROUND: We conducted a diagnostic surveillance study to identify Plasmodium, dengue virus, chikungunya virus, and Orientia tsutsugamushi infections among febrile patients who underwent triage for malaria in the outpatient department at Ispat General Hospital, Rourkela, Odisha, India. METHODS: Febrile patients were enrolled from January 2016-January 2017. Blood smears and small volumes or vacutainers of blood were collected from study participants to carry out diagnostic assays. Malaria was diagnosed using rapid diagnostic tests (RDT), microscopy, and PCR. Dengue, chikungunya, and scrub typhus infections were identified using rapid diagnostic test kits and ELISA. RESULTS: Nine hundred and fifty-four patients were prospectively enrolled in our study. The majority of patients were male (58.4%) and more than 15 years of age (66.4%). All 954 enrollees underwent additional testing for malaria; a subset of enrollees (293/954) that had larger volumes of plasma available was also tested for dengue, chikungunya and scrub typhus by either RDT or ELISA or both tests. Fifty-four of 954 patients (5.7%) were positive for malaria by RDT, or microscopy, or PCR. Seventy-four of 293 patients (25.3%) tested positive for dengue by either RDT or ELISA, and 17 of 293 patients (5.8%) tested positive for chikungunya-specific IgM by either ELISA or RDT. Ten of 287 patients tested (3.5%) were positive for scrub typhus by ELISA specific for scrub typhus IgM. Seventeen patients among 290 (5.9%) with results for ≥3 infections tested positive for more than one infection. Patients with scrub typhus and chikungunya had high rates of co-infection: of the 10 patients positive for scrub typhus, six were positive for dengue (p = 0.009), and five of 17 patients positive for chikungunya (by RDT or ELISA) were also diagnosed with malaria (p < 0.001). CONCLUSIONS: Dengue, chikungunya and scrub typhus are important etiologies of non-malarial febrile illness in Rourkela, Odisha, and comorbidity should be considered. Routine febrile illness surveillance is required to accurately establish the prevalence of these infections in this region, to offer timely treatment, and to implement appropriate methods of control.


Assuntos
Febre de Chikungunya/etiologia , Dengue/etiologia , Febre/etiologia , Tifo por Ácaros/etiologia , Adolescente , Adulto , Idoso , Febre de Chikungunya/diagnóstico , Febre de Chikungunya/epidemiologia , Criança , Pré-Escolar , Dengue/diagnóstico , Ensaio de Imunoadsorção Enzimática , Feminino , Febre/epidemiologia , Humanos , Índia/epidemiologia , Lactente , Malária Falciparum/diagnóstico , Malária Falciparum/epidemiologia , Malária Falciparum/etiologia , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Reação em Cadeia da Polimerase , Prevalência , Kit de Reagentes para Diagnóstico , Tifo por Ácaros/diagnóstico , Tifo por Ácaros/epidemiologia
20.
EMBO Mol Med ; 11(8): e9903, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31265218

RESUMO

Malaria is a highly inflammatory disease caused by Plasmodium infection of host erythrocytes. However, the parasite does not induce inflammatory cytokine responses in macrophages in vitro and the source of inflammation in patients remains unclear. Here, we identify oxidative stress, which is common in malaria, as an effective trigger of the inflammatory activation of macrophages. We observed that extracellular reactive oxygen species (ROS) produced by xanthine oxidase (XO), an enzyme upregulated during malaria, induce a strong inflammatory cytokine response in primary human monocyte-derived macrophages. In malaria patients, elevated plasma XO activity correlates with high levels of inflammatory cytokines and with the development of cerebral malaria. We found that incubation of macrophages with plasma from these patients can induce a XO-dependent inflammatory cytokine response, identifying a host factor as a trigger for inflammation in malaria. XO-produced ROS also increase the synthesis of pro-IL-1ß, while the parasite activates caspase-1, providing the two necessary signals for the activation of the NLRP3 inflammasome. We propose that XO-produced ROS are a key factor for the trigger of inflammation during malaria.


Assuntos
Inflamação/enzimologia , Macrófagos/enzimologia , Malária Cerebral/enzimologia , Malária Falciparum/enzimologia , Estresse Oxidativo , Plasmodium falciparum/patogenicidade , Espécies Reativas de Oxigênio/metabolismo , Xantina Oxidase/metabolismo , Caspase 1/metabolismo , Células Cultivadas , Citocinas/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Inflamação/sangue , Inflamação/parasitologia , Mediadores da Inflamação/metabolismo , Ativação de Macrófagos , Macrófagos/parasitologia , Malária Cerebral/sangue , Malária Cerebral/parasitologia , Malária Falciparum/sangue , Malária Falciparum/parasitologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...