RESUMO
BACKGROUND: The parasite Entamoeba histolytica is the causal agent of amoebiasis, a worldwide emerging disease. Amebic brain abscess is a form of invasive amebiasis that is both rare and frequently lethal. This condition always begins with the infection of the colon by E. histolytica trophozoites, which subsequently travel through the bloodstream to extraintestinal tissues. CASE PRESENTATION: We report a case of a 71-year-old female who reported an altered state of consciousness, disorientation, sleepiness and memory loss. She had no history of hepatic or intestinal amoebiasis. A preliminary diagnosis of colloidal vesicular phase neurocysticercosis was made based on nuclear magnetic resonance imaging (NMRI). A postsurgery immunofluorescence study was positive for the 140 kDa fibronectin receptor of E. histolytica, although a serum analysis by ELISA was negative for IgG antibodies against this parasite. A specific E. histolytica 128 bp rRNA gene was identified by PCR in biopsy tissue. The final diagnosis was cerebral amoebiasis. The patient underwent neurosurgery to eliminate amoebic abscesses and was then given a regimen of metronidazole, ceftriaxone and dexamethasone for 4 weeks after the neurosurgery. However, a rapid decline in her condition led to death. CONCLUSIONS: The present case of an individual with a rare form of cerebral amoebiasis highlights the importance of performing immunofluorescence, NMRI and PCR if a patient has brain abscess and a poorly defined diagnosis. Moreover, the administration of corticosteroids to such patients can often lead to a rapid decline in their condition.
Assuntos
Abscesso Encefálico/diagnóstico , Abscesso Encefálico/parasitologia , Infecções Parasitárias do Sistema Nervoso Central/diagnóstico , Entamebíase/diagnóstico , Idoso , Animais , Abscesso Encefálico/tratamento farmacológico , Abscesso Encefálico/cirurgia , Ceftriaxona/administração & dosagem , Infecções Parasitárias do Sistema Nervoso Central/tratamento farmacológico , Infecções Parasitárias do Sistema Nervoso Central/patologia , Infecções Parasitárias do Sistema Nervoso Central/cirurgia , Terapia Combinada , DNA de Protozoário/análise , Dexametasona/administração & dosagem , Quimioterapia Combinada , Entamoeba histolytica/genética , Entamoeba histolytica/imunologia , Entamoeba histolytica/isolamento & purificação , Entamebíase/tratamento farmacológico , Entamebíase/patologia , Entamebíase/cirurgia , Evolução Fatal , Feminino , Humanos , Metronidazol/administração & dosagem , Procedimentos Neurocirúrgicos , Testes SorológicosRESUMO
Currently, there is growing interest in the identification and purification of microbial lectins due to their involvement in the pathogenicity mechanisms of pathogens, such as Entamoeba histolytica and free-living amoebae. The Gal/GalNAc lectin from E. histolytica participates in adhesion, cytotoxicity and regulation of immune responses. Furthermore, mannose- and galactose-binding protein have been described in Acanthamoeba castellanii and Balamuthia mandrillaris, respectively and they also contribute to host damage. Finally, in Naegleria fowleri, molecules containing mannose and fucose are implicated in adhesion and cytotoxicity. Considering their relevance in the pathogenesis of the diseases caused by these protozoa, lectins appear to be promising targets in the diagnosis, vaccination and treatment of these infections.
Assuntos
Amoeba/efeitos dos fármacos , Entamoeba histolytica/efeitos dos fármacos , Lectinas/farmacologia , Fatores de Virulência , Amebíase/diagnóstico , Animais , Balamuthia mandrillaris , Entamebíase/diagnóstico , Entamebíase/tratamento farmacológico , Entamebíase/parasitologia , Glicoconjugados , Glicoproteínas , Interações Hospedeiro-Parasita , Humanos , Naegleria fowleri , VacinaçãoAssuntos
Entamebíase , Abscesso Hepático Amebiano , Doença Relacionada a Viagens , Adulto , Colômbia , Entamoeba histolytica/genética , Entamebíase/diagnóstico por imagem , Entamebíase/tratamento farmacológico , Heparina/uso terapêutico , Humanos , Abscesso Hepático Amebiano/diagnóstico por imagem , Abscesso Hepático Amebiano/tratamento farmacológico , Masculino , Meropeném/uso terapêutico , Metronidazol/uso terapêutico , México , Peru , Combinação Piperacilina e Tazobactam/uso terapêutico , Reação em Cadeia da Polimerase , Resultado do Tratamento , Reino Unido , Adulto JovemRESUMO
Herein is presented the synthesis, characterization, electrochemical studies, DFT calculations and in vitro evaluation of amoebicidal activity in trophozoites of Entamoeba histolytica of twenty ruthenium (II) mixed compounds with general formulae: [Ru(pdto)(E-E)]Clx (E-E bidentate, either neutral or negatively charged ligands). For compounds under study, O-O, N-O and N-N auxiliary donor ligands demonstrate to have a crucial impact on the electronic properties and that it is possible to modulate the antiparasitic activity. Among analyzed complexes, only four present a better performance compared to typically used metronidazole drug (IC50 < 6.80 µmol/L) to treat amebiasis disease. For studied compounds, structure-activity relationships are strongly determined by either the redox potential (E1/2) of RuII/RuIII and calculated molar volume (V) of the complexes.
Assuntos
Antiparasitários/farmacologia , Entamoeba histolytica/efeitos dos fármacos , Entamebíase/tratamento farmacológico , Compostos Organometálicos/farmacologia , Rutênio/química , Antiparasitários/química , Eletroquímica , Entamebíase/parasitologia , Compostos Organometálicos/química , Relação Estrutura-AtividadeRESUMO
Over the past 20 years, gastrointestinal infections in developing countries have been a serious health problem and are the second leading cause of morbidity among all age groups. Among pathogenic protozoans that cause diarrheal disease, the parasite Entamoeba histolytica produces amebic colitis as well as the most frequent extra-intestinal lesion, an amebic liver abscess (ALA). Usually, intestinal amebiasis and ALA are treated with synthetic chemical compounds (iodoquinol, paromomycin, diloxanide furoate, and nitroimidazoles). Metronidazole is the most common treatment for amebiasis. Although the efficacy of nitroimidazoles in killing amebas is known, the potential resistance of E. histolytica to this treatment is a concern. In addition, controversial studies have reported that metronidazole could induce mutagenic effects and cerebral toxicity. Therefore, natural and safe alternative drugs against this parasite are needed. Flavonoids are natural polyphenolic compounds. Flavonoids depend on malonyl-CoA and phenylalanine to be synthesized. Several flavonoids have anti-oxidant and anti-microbial properties. Since the 1990s, several works have focused on the identification and purification of different flavonoids with amebicidal effects, such as, -(-)epicatechin, kaempferol, and quercetin. In this review, we investigated the effects of flavonoids that have potential amebicidal activity and that can be used as complementary and/or specific therapeutic strategies against E. histolytica trophozoites. Interestingly, it was found that these natural compounds can induce morphological changes in the amebas, such as chromatin condensation and cytoskeletal protein re-organization, as well as the upregulation and downregulation of fructose-1,6-bisphosphate aldolase, glyceraldehyde-phosphate dehydrogenase, and pyruvate:ferredoxin oxidoreductase (enzymes of the glycolytic pathway). Although the specific molecular targets, bioavailability, route of administration, and doses of some of these natural compounds need to be determined, flavonoids represent a very promising and innocuous strategy that should be considered for use against E. histolytica in the era of microbial drug resistance.
Assuntos
Antiprotozoários/administração & dosagem , Antiprotozoários/farmacologia , Entamoeba histolytica/efeitos dos fármacos , Entamebíase/tratamento farmacológico , Flavonoides/administração & dosagem , Flavonoides/farmacologia , HumanosRESUMO
Bolivia is one of the countries with a high intestinal helminth and protozoan infection rate. Despite the high prevalence of the parasitic infection, nationwide preventive measures for Bolivian children have not yet been implemented. We evaluated the effect of mass stool examination and treatment as a strategy for decreasing the infection rate. This study was conducted between 2013 and 2015 in children aged 2-18 years. A total of 2,033 stool samples (575 in 2013, 815 in 2014 and 642 in 2015) were collected and examined using the formalin-ether medical sedimentation method. As an anthelminthic medicine, nitazoxanide was given to all infected children within 2 months post-examination, each year. The effect of mass stool examination and treatment was evaluated based on the changes in the overall or individual parasitic infection rates during the study period. The overall parasitic infection rate decreased significantly from 65.2% in 2013 to 43.0% in 2015; a 22.2 percentage point decrease (P<0.001). Protozoan infection accounted for a large portion of the parasitic infections, in the following rates: 62.4% in 2013, 49.3% in 2014, and 41.0% in 2015. The rate of the most common helminth infection, Hymenolepis nana, decreased significantly from 9.0% in 2013 to 6.4% in 2014 to 3.4% in 2015 (P<0.001). Prevalence of the most common pathogenic protozoan infection, Entamoeba histolytica, decreased significantly from 19.0% in 2013 to 3.0% in 2015 (P<0.001). Conversely, the rate of Giardia intestinalis increased significantly from 16.5% in 2013 to 21.2% in 2015 (P<0.01). Mass stool examination and treatment for intestinal helminth and protozoan infections was effective for decreasing the overall parasitic infection rate in the study population, excluding Giardia intestinalis. Further studies on the long-term effect of mass stool examination and treatment for decreasing all intestinal parasitic infection rates in Bolivian children are needed.
Assuntos
Entamebíase/tratamento farmacológico , Fezes/parasitologia , Giardíase/tratamento farmacológico , Helmintíase/tratamento farmacológico , Himenolepíase/tratamento farmacológico , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/epidemiologia , Programas de Rastreamento , Infecções por Protozoários/epidemiologia , Adolescente , Animais , Bolívia/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Entamoeba histolytica/isolamento & purificação , Entamebíase/epidemiologia , Entamebíase/parasitologia , Entamebíase/prevenção & controle , Feminino , Giardia lamblia/isolamento & purificação , Giardíase/epidemiologia , Giardíase/parasitologia , Giardíase/prevenção & controle , Helmintíase/epidemiologia , Helmintíase/parasitologia , Helmintíase/prevenção & controle , Humanos , Himenolepíase/epidemiologia , Himenolepíase/parasitologia , Himenolepíase/prevenção & controle , Hymenolepis/isolamento & purificação , Enteropatias Parasitárias/prevenção & controle , Masculino , Nitrocompostos , Prevalência , Estudantes , Tiazóis/uso terapêutico , Adulto JovemRESUMO
The flavonoid kaempferol obtained from Helianthemum glomeratum, an endemic Mexican medicinal herb used to treat gastrointestinal disorders, has been shown to inhibit growth of Entamoeba histolytica trophozoites in vitro; however, the mechanisms associated with this activity have not been documented. Several works reported that kaempferol affects cytoskeleton in mammalian cells. In order to gain insights into the action mechanisms involved in the anti-amoebic effect of kaempferol, here we evaluated the effect of this compound on the pathogenic events driven by the cytoskeleton during E. histolytica infection. We also carried out a two dimensional gel-based proteomic analysis to evidence modulated proteins that could explain the phenotypical changes observed in trophozoites. Our results showed that kaempferol produces a dose-dependent effect on trophozoites growth and viability with optimal concentration being 27.7 µM. Kaempferol also decreased adhesion, it increased migration and phagocytic activity, but it did not affect erythrocyte binding nor cytolytic capacity of E. histolytica. Congruently, proteomic analysis revealed that the cytoskeleton proteins actin, myosin II heavy chain and cortexillin II were up-regulated in response to kaempferol treatment. In conclusion, kaempferol anti-amoebic effects were associated with deregulation of proteins related with cytoskeleton, which altered invasion mechanisms.
Assuntos
Citoesqueleto/efeitos dos fármacos , Entamoeba histolytica/efeitos dos fármacos , Quempferóis/farmacologia , Proteínas de Protozoários/metabolismo , Trofozoítos/efeitos dos fármacos , Animais , Células CACO-2 , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Cistaceae/química , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto/fisiologia , Relação Dose-Resposta a Droga , Entamoeba histolytica/crescimento & desenvolvimento , Entamoeba histolytica/metabolismo , Entamebíase/tratamento farmacológico , Entamebíase/parasitologia , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Humanos , México , Fagocitose/efeitos dos fármacos , Plantas Medicinais/química , Proteômica , Trofozoítos/crescimento & desenvolvimento , Trofozoítos/metabolismoRESUMO
In view of the serious health problems concerning infectious diseases in heavily populated areas, we followed the strategy of lead compound diversification to evaluate the near-by chemical space for new organic compounds. To this end, twenty derivatives of nitazoxanide (NTZ) were synthesized and tested for activity against Entamoeba histolytica parasites. To ensure drug-likeliness and activity relatedness of the new compounds, the synthetic work was assisted by a quantitative structure-activity relationships study (QSAR). Many of the inherent downsides - well-known to QSAR practitioners - we circumvented thanks to workarounds which we proposed in prior QSAR publication. To gain further mechanistic insight on a molecular level, ligand-enzyme docking simulations were carried out since NTZ is known to inhibit the protozoal pyruvate ferredoxin oxidoreductase (PFOR) enzyme as its biomolecular target.
Assuntos
Antiprotozoários/química , Antiprotozoários/farmacologia , Entamoeba histolytica/efeitos dos fármacos , Entamoeba histolytica/enzimologia , Piruvato Sintase/antagonistas & inibidores , Tiazóis/química , Tiazóis/farmacologia , Entamebíase/tratamento farmacológico , Entamebíase/parasitologia , Humanos , Simulação de Acoplamento Molecular , Nitrocompostos , Piruvato Sintase/metabolismo , Relação Quantitativa Estrutura-AtividadeRESUMO
INTRODUCTION: Febrile neutropenia is a common complication of chemotherapy treatment of malignant hematological diseases. However, there is insufficient information regarding the infectious complications of febrile neutropenia in our country. Objective. We will evaluate the microbial characteristics of bacterial and fungal isolates and the clinical outcome of patients with febrile neutropenia who received medical attention at an oncological reference center in Colombia. MATERIALS AND METHODS: A prospective case series included patients with histologically confirmed oncological disease, who were admitted because of febrile neutropenia or presented with febrile neutropenia during hospitalization. Patients with benign hematological diseases were excluded. Demographic, microbiological, and clinical features as well as treatment and outcome information from patients with febrile neutropenia were obtained. We performed univariate and multivariate analyses, with mortality defined as the outcome. RESULTS: One hundred and thirty episodes of febrile neutropenia were identified in 104 patients. The mean patient age was 19, and 53% of the patients were male. Approximately 86% of the episodes occurred in patients with hematological disorders. An infectious site was identified in 65% of patients; 41% and 24% of the febrile neutropenia pateints´ episodes exhibited a localized infectious focus and developed bloodstream infections, respectively. The majority of infections were found in blood, urine, gastrointestinal tract, and soft tissue. Distribution analysis of microbiological isolates revealed 46.4% Gram-negative bacilli, 38.4% Gram-positive cocci, 8% fungi, and 7.1% parasites; there was a 7.7% mortality rate. Appropriate empirical antimicrobial therapy was a protection-related factor in multivariate analyses (OR= 0.17; 0.034 - 0.9 95% CI; p= 0.037). CONCLUSIONS: The mortality rate was relatively low and comparable to the rate reported by developed countries. Inappropriate empirical antimicrobial therapy was the main factor associated with mortality.
Assuntos
Infecções Bacterianas/etiologia , Institutos de Câncer , Neutropenia Febril Induzida por Quimioterapia/epidemiologia , Prescrição Inadequada/estatística & dados numéricos , Micoses/etiologia , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Antibioticoprofilaxia/estatística & dados numéricos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Neutropenia Febril Induzida por Quimioterapia/complicações , Criança , Pré-Escolar , Colômbia/epidemiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/etiologia , Entamebíase/tratamento farmacológico , Entamebíase/epidemiologia , Entamebíase/etiologia , Entamebíase/parasitologia , Feminino , Mortalidade Hospitalar , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Micoses/tratamento farmacológico , Micoses/epidemiologia , Micoses/microbiologia , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Especificidade de Órgãos , Estudos Prospectivos , Recidiva , Adulto JovemRESUMO
Introduction. Febrile neutropenia is a common complication of chemotherapy treatment of malignant hematological diseases. However, there is insufficient information regarding the infectious complications of febrile neutropenia in our country. Objective. We will evaluate the microbial characteristics of bacterial and fungal isolates and the clinical outcome of patients with febrile neutropenia who received medical attention at an oncological reference center in Colombia. Materials and methods. A prospective case series included patients with histologically confirmed oncological disease, who were admitted because of febrile neutropenia or presented with febrile neutropenia during hospitalization. Patients with benign hematological diseases were excluded. Demographic, microbiological, and clinical features as well as treatment and outcome information from patients with febrile neutropenia were obtained. We performed univariate and multivariate analyses, with mortality defined as the outcome. Results. One hundred and thirty episodes of febrile neutropenia were identified in 104 patients. The mean patient age was 19, and 53% of the patients were male. Approximately 86% of the episodes occurred in patients with hematological disorders. An infectious site was identified in 65% of patients; 41% and 24% of the febrile neutropenia pateints´ episodes exhibited a localized infectious focus and developed bloodstream infections, respectively. The majority of infections were found in blood, urine, gastrointestinal tract, and soft tissue. Distribution analysis of microbiological isolates revealed 46.4% Gram-negative bacilli, 38.4% Gram-positive cocci, 8% fungi, and 7.1% parasites; there was a 7.7% mortality rate. Appropriate empirical antimicrobial therapy was a protection-related factor in multivariate analyses (OR= 0.17; 0.034 - 0.9 95% CI; p= 0.037). Conclusions. The mortality rate was relatively low and comparable to the rate reported by developed countries. Inappropriate empirical antimicrobial therapy was the main factor associated with mortality.
Introducción. La neutropenia febril es una complicación frecuente de la quimioterapia para las neoplasias hematológicas. Se dispone de escasa información de sus complicaciones infecciosas en nuestro medio. Objetivo. Evaluar las características clínicas y microbiológicas de pacientes con neutropenia febril, así como su resultado clínico en una institución de referencia oncológica en Colombia. Materiales y métodos. Se conformó prospectivamente una serie de casos con pacientes con enfermedad oncológica confirmada, que consultaron o presentaron neutropenia febril durante la hospitalización. Se excluyeron aquellos con enfermedad hematológica benigna. Se recolectaron datos sobre variables demográficas, microbiológicas, clínicas, de tratamiento y de resultado de los pacientes. Se llevaron a cabo un análisis univariado y uno multivariado, con la mortalidad como resultado. Resultados. Se identificaron 130 episodios de neutropenia febril en 104 pacientes, con una edad media de 19 años y 53 % masculinos. El 86 % de los episodios ocurrieron en pacientes con alteraciones hematológicas. Se demostró infección en 65 % de los casos: 41 % con un foco infeccioso localizado y 27,7 % con bacteriemia. Los principales focos infecciosos se localizaron en el torrente sanguíneo, el aparato urinario, el sistema gastrointestinal, la piel y los tejidos blandos. De los aislamientos microbiológicos, 46,4 % fueron bacilos Gram negativos, 38,4 %, cocos Gram positivos, 9 %, hongos y, 7,1%, parásitos. La mortalidad global fue de 7,7 %. En el análisis multivariado la utilización de un tratamiento empírico apropiado se correlacionó con una menor mortalidad, de forma independiente (OR=0,17; IC 95% 0,034-0,9; p=0,037). Conclusiones. La tasa de mortalidad fue relativamente baja y fue comparable con lo reportado en países desarrollados. El tratamiento antimicrobiano inapropiado fue el principal factor asociado con mortalidad.
Assuntos
Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Infecções Bacterianas/etiologia , Institutos de Câncer , Neutropenia Febril Induzida por Quimioterapia/epidemiologia , Prescrição Inadequada/estatística & dados numéricos , Micoses/etiologia , Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Neutropenia Febril Induzida por Quimioterapia/complicações , Colômbia/epidemiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/etiologia , Entamebíase/tratamento farmacológico , Entamebíase/epidemiologia , Entamebíase/etiologia , Entamebíase/parasitologia , Mortalidade Hospitalar , Micoses/tratamento farmacológico , Micoses/epidemiologia , Micoses/microbiologia , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Especificidade de Órgãos , Estudos Prospectivos , RecidivaRESUMO
Protein kinases (PKs) of parasitic protozoa are being evaluated as drug targets. A large number of protein kinases within the protein kinome of Entamoeba histolytica strongly suggest that protein phosphorylation is a key component of pathogenesis regulation by this parasite. PI3 K and Src are kinases previously described in this parasite, but their role is poorly understood. Here, the effect of Src-1-inhibitor and PI3 K inhibitor (Wortmannin) on the virulence factors of E. histolytica was evaluated. Results show that both inhibitors affect the actin cytoskeleton and the amoebic movement. Also, the proteolytic activity is diminished by Wortmannin, but not by Src-inhibitor-1; however, the phagocytic capacity is diminished by Wortmannin and Src-1-inhibitor. Finally, we found that the virulence in vivo of E. histolytica is affected by Wortmannin but not by Src-1-inhibitor. This study opens the way for the design of anti-amoebic drugs based on kinase inhibition.
Assuntos
Entamoeba histolytica/efeitos dos fármacos , Entamoeba histolytica/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Fatores de Virulência/metabolismo , Citoesqueleto de Actina/efeitos dos fármacos , Androstadienos/farmacologia , Androstadienos/uso terapêutico , Animais , Células Cultivadas , Cricetinae , Entamoeba histolytica/patogenicidade , Entamebíase/tratamento farmacológico , Entamebíase/patologia , Humanos , Masculino , Fagocitose/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Proteólise/efeitos dos fármacos , Wortmanina , Quinases da Família src/metabolismoRESUMO
To determine the prevalence of Entamoeba histolytica/E. dispar (Eh/Ed) in chronic hemodialysis (HD) patients, we collected 330 samples of feces from 110 patients, and nine individuals were found to be positive for Eh/Ed. We compared the infected patients with a group of 14 uninfected HD patients. Both groups were analyzed for their signs, symptoms and socio-economic characteristics using questionnaires. Blood tests were also performed in both the groups. Although both groups did not differ statistically with respect to their signs, symptoms and socio-economic conditions, there was a trend toward a greater number of individuals with diarrhea in the Eh/Ed infected group. In conclusion, we suggest that a parasitological examination of the patient's stool to detect the Eh/Ed complex should be included with the routine tests so that those patients with a positive fecal test could be initiated on appropriate anti-Eh/Ed therapy.
Assuntos
Entamoeba histolytica/isolamento & purificação , Entamebíase/epidemiologia , Falência Renal Crônica/terapia , Diálise Renal , Brasil/epidemiologia , Estudos de Casos e Controles , Diarreia/epidemiologia , Diarreia/parasitologia , Entamebíase/diagnóstico , Entamebíase/tratamento farmacológico , Entamebíase/parasitologia , Fezes/parasitologia , Feminino , Humanos , Falência Renal Crônica/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Diálise Renal/efeitos adversos , Medição de Risco , Fatores de Risco , Inquéritos e QuestionáriosRESUMO
The history of Entamoeba histolytica is very confuse and shows several wrong concepts about the parasite and its relationship with the host. The poor correlation between the prevalence of asymptomatic and symptomatic amebiasis originated the proposal of three explicative hypothesis, among them was the concept of Brumpt that E. histolytica comprised two morphologically identical species, E. dysenteriae and E. dispar. The application of modern molecular techniques irrefutably proved that E. histolytica was really a complex of two species, confirming the concept of Brumpt almost 7 decades later. Recent studies have identified in humans E. moshkovskii, morphologically indistinguishable from E. histolytica and E. dispar, a great genetic diversity within each of these species, and heterogeneity in virulence among E. histolytica strains. The redescription of E. dispar, and the recovery of E. moshkovskii from humans have had a major impact in our understanding of E. histolytica and amebiasis with important clinical and epidemiologic implications. This has led to the need of a reevaluation of the infection in terms of prevalence and morbidity in the global population and to study the geographic distribution, prevalence, and transmission pattern of E. histolytica strains in order to detect those with epidemiologic relevance and predict the risk of amebic disease in a population.
Assuntos
Entamoeba/isolamento & purificação , Entamebíase/história , Parasitologia/história , Amebicidas/uso terapêutico , Países em Desenvolvimento , Entamoeba/classificação , Entamoeba/enzimologia , Entamoeba histolytica/genética , Entamoeba histolytica/isolamento & purificação , Entamoeba histolytica/fisiologia , Entamebíase/diagnóstico , Entamebíase/tratamento farmacológico , Entamebíase/epidemiologia , Entamebíase/parasitologia , Previsões , História do Século XIX , História do Século XX , História do Século XXI , Interações Hospedeiro-Parasita , Humanos , Isoenzimas/análise , Parasitologia/tendências , Proteínas de Protozoários/análise , Especificidade da Espécie , VirulênciaRESUMO
BACKGROUND: Cutaneous amebiasis (CA), which is still a health problem in developing countries, is important to diagnose based on its clinical and histopathologic features. OBSERVATIONS: Retrospective medical record review of 26 patients with CA (22 adults and 4 children) treated from 1955 to 2005 was performed. In addition to the age and sex of the patients, the case presentation, associated illness or factors, and method of establishing the diagnosis, clinical pictures and microscopic slides were also analyzed. CONCLUSIONS: Cutaneous amebiasis always presents with painful ulcers. The ulcers are laden with amebae, which are relatively easy to see microscopically with routine stains. Erythrophagocytosis is an unequivocal sign of CA. Amebae reach the skin via 2 mechanisms: direct and indirect. Amebae are able to reach the skin if there is a laceration (port of entry) and if conditions in the patient are favorable. Amebae are able to destroy tissues by means of their physical activity, phagocytosis, enzymes, secretagogues, and other molecules.
Assuntos
Entamoeba histolytica/isolamento & purificação , Entamebíase/diagnóstico , Entamebíase/epidemiologia , Dermatopatias Parasitárias/diagnóstico , Dermatopatias Parasitárias/epidemiologia , Adulto , Distribuição por Idade , Animais , Antiparasitários/uso terapêutico , Biópsia por Agulha , Pré-Escolar , Países em Desenvolvimento , Entamebíase/tratamento farmacológico , Feminino , Humanos , Imuno-Histoquímica , Incidência , Lactente , Masculino , México/epidemiologia , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Distribuição por Sexo , Dermatopatias Parasitárias/terapiaRESUMO
The protozoa E. histolytica is the etiologic agent of human amebiasis, the identification of its pathogenicity has been of great aid in the search of important antigens for immunodiagnostic and inmunoprofilaxis. In 1995 the isolation and axenization of the first two strains of Venezuelan E. histolytica were described from symptomatic patients, which were denominated: IULA 1092:1 and IULA: 0593:2 These strains have been evaluated through studies of electrophoretic profiles, demonstrating the presence of type II zymodemes, characteristic of pathogenic strains. Also, they have shown to be of high virulence, they present a complex pattern of reactivity and the presence of a marker antigen of pathogenicity. The isoenzymatic analysis has shown correlation with the genotypic analysis, showing a genotypic organization typical of a pathogenic strain. With this strain, it has been possible to evaluate all the amebiasis cases sent to the Institute of Clinical Immunology of Universidad de Los Andes, in Merida, Venezuela. These strains have been useful, here, as well as in other sites, when using their antigens to evaluate urban and even indigenous populations. They can be used, like native strains of reference, in diagnostic tests and prophylaxis for this parasitosis. The limitations of the microscopic analysis, specifically, the false amebiasis diagnosis and its inability to discriminate between infections caused by E. histolytica and E. dispar have led to the development of laboratory procedures that allow for the detection of components of the species present. The success of such procedures would result in a diminution of unnecessary treatments, which could be the cause of antiamoebic drug resistance.
Assuntos
Entamebíase , Amebicidas/uso terapêutico , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , DNA de Protozoário/análise , Entamoeba histolytica/genética , Entamoeba histolytica/imunologia , Entamoeba histolytica/isolamento & purificação , Entamoeba histolytica/patogenicidade , Entamebíase/diagnóstico , Entamebíase/tratamento farmacológico , Entamebíase/epidemiologia , Genoma , Humanos , Incidência , Parasitologia/métodos , Reação em Cadeia da Polimerase , Especificidade da EspécieRESUMO
OBJECTIVE: Gastrointestinal parasites continue to be an important cause of morbidity and stunting among children in developing countries. We evaluated the effect of vitamin A and zinc supplementation on infections by Giardia lamblia, Ascaris lumbricoides, and Entamoeba histolytica. METHODS: A randomized, double-blind, placebo-controlled trial was conducted among 707 children who were 6 to 15 months of age and from periurban areas of Mexico City, Mexico, between January 2000 and May 2002. Children, who were assigned to receive either vitamin A every 2 months, a daily zinc supplement, a combined vitamin A and zinc supplement, or a placebo, were followed for 1 year. The primary end points were the 12-month rates and durations of infection for the 3 parasites and rates of parasite-associated diarrheal disease as determined in stools collected once a month and after diarrheal episodes. RESULTS: G. lamblia infections were reduced and A. lumbricoides infections increased among children in the combined vitamin A and zinc group or the zinc alone group, respectively. Durations of Giardia infections were reduced among children in all 3 treatment arms, whereas Ascaris infections were reduced in the vitamin A and zinc group. In contrast, E. histolytica infection durations were longer among zinc-supplemented children. Finally, E. histolytica- and A. lumbricoides-associated diarrheal episodes were reduced among children who received zinc alone or a combined vitamin A and zinc supplement, respectively. CONCLUSIONS: We found that vitamin A and zinc supplementation was associated with distinct parasite-specific health outcomes. Vitamin A plus zinc reduces G. lamblia incidence, whereas zinc supplementation increases A. lumbricoides incidence but decreases E. histolytica-associated diarrhea.
Assuntos
Enteropatias Parasitárias/tratamento farmacológico , Oligoelementos/uso terapêutico , Vitamina A/uso terapêutico , Vitaminas/uso terapêutico , Zinco/uso terapêutico , Animais , Ascaríase/tratamento farmacológico , Ascaris lumbricoides , Criança , Diarreia/tratamento farmacológico , Diarreia/parasitologia , Suplementos Nutricionais , Método Duplo-Cego , Quimioterapia Combinada , Entamebíase/tratamento farmacológico , Giardíase/tratamento farmacológico , Humanos , MéxicoRESUMO
Entamoeba histolytica can infect any organ of the body, but only one case of renal involvement has been reported till now in the literature. We report a rare case of amoebic renal cyst in a 78-year showing favorable outcome with metronidazole treatment and therapeutic drainage.
Assuntos
Entamoeba histolytica/isolamento & purificação , Entamebíase/diagnóstico , Doenças Renais Císticas/parasitologia , Idoso , Animais , Antiprotozoários/uso terapêutico , Entamebíase/tratamento farmacológico , Feminino , Humanos , Doenças Renais Císticas/tratamento farmacológico , Metronidazol/uso terapêutico , Tomografia Computadorizada por Raios XRESUMO
Entamoeba histolytica can infect any organ of the body, but only one case of renal involvement has been reported till now in the literature. We report a rare case of amoebic renal cyst in a 78-yearshowing favorable outcome with metronidazole treatment and therapeutic drainage.
Assuntos
Humanos , Animais , Feminino , Idoso , Entamoeba histolytica , Entamebíase/diagnóstico , Doenças Renais Císticas , Antiprotozoários/uso terapêutico , Entamebíase/tratamento farmacológico , Doenças Renais Císticas , Metronidazol/uso terapêutico , Tomografia Computadorizada por Raios XRESUMO
Genital amebiasis by Entamoeba histolytica is rare, even in Mexico where the disease is endemic. We report a case of genital amebiasis in a female patient with a recto-perineal fistula and two-week history of a profuse vaginal discharge, a painful and friable vulvar ulcer and induration in gluteal and inner side of thighs. The PAP smear and the biopsy showed trophozoites, no malignant cells were observed. The findings were compatible with genital amebiasis. The serology test for E. histolytica was positive (> 1: 512). The patient was treated with metronidazol 750 mg tid for 3 weeks. Complete resolution was achieved. The long term fistula, the low socioeconomic status, the poor hygiene and diabetes mellitus of a recent onset were probably the risk factors associated to this infection. We reviewed the literature.
Assuntos
Entamebíase , Doenças da Vulva/parasitologia , Entamebíase/diagnóstico , Entamebíase/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade , Doenças da Vulva/diagnóstico , Doenças da Vulva/tratamento farmacológicoRESUMO
This study sought to examine whether the administration of quinfamide at 3- or 6-month intervals diminished the frequency of Entamoeba histolytica cysts in stool samples compared to controls. The prospective, longitudinal, randomized, single-blind study examined children from six primary schools in Celaya and Neutla, Guanajuato. Of the 1,524 students in these schools, we selected participants for the study as follows: Children were included in the study if their parents agreed in writing to the study and if the children demonstrated evidence of E. histolytica cysts after a parasitoscopic analysis by concentration (PSC) in three samples over consecutive days using Faust"s method. Those included in the study received a single 4.3-g/kg dose of quinfamide, and we performed PSC on days 5, 6, and 7 following dose administration to examine whether quinfamide had affected the presence of the cysts. The study participants who tested negative for cysts were divided into three groups: Group 1 had 102 patients who underwent quinfamide treatment and three CPS analyses after the 12 months of the study; Group 2 had 98 subjects who underwent the quinfamide treatment and three CPS analyses at months 3, 6, 9, and 12 after their entrance into the study; and Group 3 had 102 patients, who underwent the quinfamide treatment and series of three CPS analyses at months 6 and 12 of the study. All participants received the dose of quinfamide after providing stool samples and after a clinical gastrointestinal history was obtained. Further clinical gastrointestinal data were collected 5 days after the quintamide dose was administered. We used EpiInfo 6.0 for statistical analysis, calculating c2 and p values for the clinical data and the CPS data after the 12 months concluded. Of the initial samples of 1,524 subjects, 308 (20.2%) had Entamoebic cysts. Of these, six were further eliminated because they did not meet the inclusion requirements. At the conclusion of the study, Group 1 presented with 37.6% of subjects still testing positive for cysts; of Group 2, 12.5% tested positive; and in Group 3, 23.5% of participants tested positive for cysts (chi2 = 16.8; df = 2; p = 0.0002). For comparisons of groups 1 and 2 and 1 and 3, p < 0.05; for the comparison of groups 2 and 3, p > 0.05. We conclude that antiamoebic chemoprophylaxis can be a choice for control of amoebic infection where personal hygiene and food consumption habits are not improving.