RESUMO
Free living amoebae (FLA) can be found in different environments, where they feed on diverse microorganisms. Some bacteria preyed by FLA are called amoeba-resistant bacteria (ARB), as they can resist to lysosomal fusion and are capable of multiplying and evading FLA after internalization, propagating in the environment. Despite the health risks due to the existence of pathogenic and opportunistic species that are ARB and the pathogenicity of some FLA species, there are no water quality protocols to analyze the presence of ARB or FLA. In this sense, our study aimed to isolate FLA through amoebal enrichment and to identify ARB using amoebal coculture in water samples from a public park and two hospitals in southern Brazil. As a result, 9 different microorganisms genera have been identified through amoebal coculture, including fastidious Legionella spp. and Bosea vestrisii. From the positive samples for FLA, by amoebal enrichment, Acanthamoeba spp., Vermamoeba vermiformis and Naegleria spp. were identified in 14 amoebic isolates. The methodologies used in this work proved to be effective as simple and low-cost methods to be used in the implementation in water quality control of anthropogenic environments.
Assuntos
Amoeba , Monitoramento Ambiental , Purificação da Água , Amoeba/isolamento & purificação , Bradyrhizobiaceae , Brasil , Técnicas de Cocultura , Legionella , Controle de Qualidade , ÁguaRESUMO
Little is known about the prevalence of Balamuthia mandrillaris within the environment due to its difficult isolation, but once an axenic culture is established, it is relatively easy to maintain. As most of the time researchers are interested mainly in isolating B. mandrillaris from environmental samples, the flora that accompanies it becomes second in importance. Therefore, this study aimed to determine which potentially pathogenic free-living amoebae, in addition to B. mandrillaris, could be found co-inhabiting a source of natural thermal water called "Agua Caliente" (Mexico), where this amoeba has previously been detected twice by molecular methods. A third sampling from this same source was carried out to try to isolate B. mandrillaris and other free-living amoebae using 37 and 45⯰C as isolation temperatures. For PCR techniques, specific primers were used for B. mandrillaris, Naegleria fowleri, and Acanthamoeba species, plus a universal primer set for the eukaryotic 18S SSU rRNA gene for other isolated amoebae. PCR products were sequenced for final identification. 42 strains of the primary isolate were obtained, but only 34 could be kept in culture. Of them, 23 strains were identified as Naegleria lovaniensis, eight strains as Acanthamoeba jacobsi, two strains as Stenamoeba sp. and only one was identified as Vermamoeba vermiformis. The isolation of B. mandrillaris was once again not successful, but the presence of potentially pathogenic and nonpathogenic free-living amoebae is reported for the first time in this type of water in Mexico thanks to molecular methodology.
Assuntos
Amoeba/patogenicidade , Fontes Termais/parasitologia , Acanthamoeba/classificação , Acanthamoeba/genética , Acanthamoeba/isolamento & purificação , Acanthamoeba/patogenicidade , Amoeba/classificação , Amoeba/genética , Amoeba/isolamento & purificação , Balamuthia mandrillaris/classificação , Balamuthia mandrillaris/genética , Balamuthia mandrillaris/isolamento & purificação , Balamuthia mandrillaris/patogenicidade , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Genótipo , Fontes Termais/química , Concentração de Íons de Hidrogênio , México , Naegleria fowleri/classificação , Naegleria fowleri/genética , Naegleria fowleri/isolamento & purificação , Naegleria fowleri/patogenicidade , Filogenia , Reação em Cadeia da Polimerase , Espectrofotometria , TemperaturaAssuntos
Amoeba , Amoeba/classificação , Amoeba/citologia , Amoeba/isolamento & purificação , Humanos , PeruRESUMO
Acanthamoeba keratitis is a sight-threatening infectious disease. Resistance of the cystic form of the protozoan to biocides and the potential toxicity of chemical compounds to corneal cells are the main concerns related to long-term treatment with the clinically available ophthalmic drugs. Currently, a limited number of recognized antimicrobial agents are available to treat ocular amoebic infections. Topical application of biguanide and diamidine antiseptic solutions is the first-line therapy. We consider the current challenges when treating Acanthamoeba keratitis and review the chemical properties, toxicities, and mechanisms of action of the available biocides. Antimicrobial therapy using anti-inflammatory drugs is controversial, and aspects related to this topic are discussed. Finally, we offer our perspective on potential improvement of the effectiveness and safety of therapeutic profiles, with the focus on the quality of life and the advancement of individualized medicine.
Assuntos
Ceratite por Acanthamoeba/tratamento farmacológico , Acanthamoeba , Amoeba/isolamento & purificação , Antiprotozoários/uso terapêutico , Desinfetantes/uso terapêutico , Infecções Oculares Parasitárias/tratamento farmacológico , Ceratite por Acanthamoeba/parasitologia , Animais , Infecções Oculares Parasitárias/parasitologia , HumanosRESUMO
Introducción: las amebas de vida libre (AVL) han sido aisladas de hábitat incluyendo: agua, suelo y vegetación. Los cambios ecológicos y la incursión de estos hábitats, han hecho que puedan invadir un hospedero y vivir como parásitos dentro de él. Por esto, las especies de los géneros Acanthamoeba y Naegleria han sido asociadas con infecciones oportunistas. Objetivo: evaluar la presencia de las amebas de vida libre en fuentes de agua natural en el municipio de Turbaco, con el fin de que sean consideradas en la conducta diagnóstica y terapéutica por las entidades de salud pertinentes. Métodos: se realizó un estudio descriptivo, transversal en los arroyos Matute, Mameyal y Cucumán del municipio de Turbaco - Bolívar. La identificación se hizo mediante el estudio de los frescos de las fuentes de agua observando características morfológicas de las amebas. Resultados: de un total de 54 muestras se obtuvo una positividad del 55,5 por ciento para una o más AVL. Con mayor frecuencia Naegleria sp con un 44,4 por ciento y Acanthamoeba sp, en un 7,4 por ciento. Además, se encontraron otros microorganismos responsables de parasitosis intestinales como: Giardia intestinalis, Blastocystis hominis y Retortomonas intestinalis. Conclusión: los arroyos estudiados son hábitat de las AVL, demostrando que están presentes en el ambiente y que son frecuentes en zonas donde el ser humano suele practicar ciertas actividades, sin embargo, la proporción de Naegleria sp. permite alertar aún más a la población puesto que esta ameba puede afectar a todo tipo de individuo independiente de su estado inmunológico(AU)
Introduction: free-living amoebae (FLAs) have been isolated from habitats such as water, soil and vegetation. As a result of ecological changes and incursion into these habitats, free-living amoebae have invaded hosts and settled within them as parasites. This is the reason why the species of genera Acanthamoeba and Naegleria have been associated with opportunistic diseases. Objective: determine the presence of free-living amoebae in natural water sources from the municipality of Turbaco, so they are taken into account by the corresponding health institutions in the design of diagnostic and therapeutic actions. Methods: a descriptive cross-sectional study was conducted of streams Matute, Mameyal and Cucumán in the municipality of Turbaco, Bolívar. Identification was based on the study of fresh water from the sources selected and observation of the morphological characteristics of amoebae. Results: of the total 54 samples, 55.5 percent tested positive for one or more FLAs. The most common were Naegleria sp with 44.4 percent and Acanthamoeba sp with 7.4 percent. Microorganisms were also found which cause intestinal parasitic disease, such as Giardia intestinalis, Blastocystis hominis and Retortomonas intestinalis. Conclusion: the streams studied are habitats for FLAs, showing that the latter are present in the environment and are common in areas where human beings perform certain activities. However, the proportion of Naegleria sp. makes it necessary to emphatically alert the population, since this amoeba may affect all individuals, irrespective of their immune status(AU)
Assuntos
Animais , Infecções Protozoárias do Sistema Nervoso Central/transmissão , Rios/parasitologia , Amoeba/isolamento & purificação , Epidemiologia Descritiva , Estudos Transversais , Ecossistema , Estudo ObservacionalRESUMO
Free-living amoebae (FLA) are protozoa that are widely distributed in nature. They are important in the cycling of nutrients in aquatic food chains, but their distribution in natural aquatic environments is not well known. We conducted a survey to determine the presence and distribution of FLA and their relation to some physicochemical parameters in streams of the Mexico Basin in Central Mexico. Thirty-two sites from 18 streams were sampled. Samples were centrifuged and cultured onto NNA-media to isolate amoebae. Identifications were based on morphology. The pathogenicity of Acanthamoeba isolates was tested. Oxygen saturation, temperature, pH, specific conductance, water flow, dissolved reactive phosphorus, nitrites, nitrates, ammonia, dissolved inorganic nitrogen and coliforms were determined. One hundred-and-twenty FLA representing 18 genera were identified. The most frequent genera were Vannella, Rosculus and Acanthamoeba. The frequency of potentially pathogenic FLA was low and only 3 Acanthamoeba isolates were invasive in mice. The highest species richness of FLA was found in streams located into agriculture activity areas and those close to small villages that discharge wastewater into them. Water temperatures were always below 17°C. Oxygen saturation and pH were within the limits for the growth of most FLA. The presence of Acanthamoeba and Naegleria was low; nevertheless, they include potentially pathogenic species and can act as vectors and reservoirs for microbial pathogens and can produce human infections.
Assuntos
Amoeba/fisiologia , Rios/parasitologia , Amoeba/isolamento & purificação , Amoeba/patogenicidade , Animais , Carga Bacteriana , Biodiversidade , Enterobacteriaceae/crescimento & desenvolvimento , México , Camundongos , Rios/química , Rios/microbiologia , Estações do Ano , Temperatura , VirulênciaRESUMO
Free-living amoebae have been found in soil, air and a variety of aquatic environments, but few studies have been conducted on industrial wastewater and none on wastewater from the textile industry. The aim of this study was to determine the presence and distribution of free-living amoebae in a biological treatment system that treats textile industrial wastewater. Samples were taken from input, aeration tank, sedimentation tank and output. Samples were centrifuged at 1200g for 15min, the sediment was seeded on non-nutritive agar with Enterobacter aerogenes (NNE) and the plates were incubated at 30 and 37°C. Free-living amoebae were present in all stages of the treatment system. The highest number of amoebic isolates was found in the aeration tank and no seasonal distribution was observed during the year. A total of 14 amoeba genera were isolated: Acanthamoeba, Echinamoeba, Korotnevella, Mayorella, Naegleria, Platyamoeba, Saccamoeba, Stachyamoeba, Thecamoeba, Vahlkampfia, Vannella, Vermamoeba, Vexillifera and Willaertia. The most frequently found amoebae were Acanthamoeba and Vermamoeba which were found in all treatment system stages. The constant presence and diversity of free-living amoebae in the treatment system were important findings due to the characteristics of the wastewater from the textile plant in terms of the residue content from colorants, fixers, carriers, surfactants, etc., used in fabric dyeing and finishing processes. The factors that determined the presence and distribution of amoebae in the activated sludge system were their capacity to form cysts, which allowed them to resist adverse conditions; food availability; an average temperature of 27-33°C; dissolved oxygen in average concentrations above 2mg/L, and pH in a range of 5.9-7.1.
Assuntos
Amoeba/isolamento & purificação , Resíduos Industriais , Indústria Têxtil , Águas Residuárias/parasitologia , Amoeba/classificação , Concentração de Íons de Hidrogênio , México , TemperaturaRESUMO
Tropical peatlands represent globally important carbon sinks with a unique biodiversity and are currently threatened by climate change and human activities. It is now imperative that proxy methods are developed to understand the ecohydrological dynamics of these systems and for testing peatland development models. Testate amoebae have been used as environmental indicators in ecological and palaeoecological studies of peatlands, primarily in ombrotrophic Sphagnum-dominated peatlands in the mid- and high-latitudes. We present the first ecological analysis of testate amoebae in a tropical peatland, a nutrient-poor domed bog in western (Peruvian) Amazonia. Litter samples were collected from different hydrological microforms (hummock to pool) along a transect from the edge to the interior of the peatland. We recorded 47 taxa from 21 genera. The most common taxa are Cryptodifflugia oviformis, Euglypha rotunda type, Phryganella acropodia, Pseudodifflugia fulva type and Trinema lineare. One species found only in the southern hemisphere, Argynnia spicata, is present. Arcella spp., Centropyxis aculeata and Lesqueresia spiralis are indicators of pools containing standing water. Canonical correspondence analysis and non-metric multidimensional scaling illustrate that water table depth is a significant control on the distribution of testate amoebae, similar to the results from mid- and high-latitude peatlands. A transfer function model for water table based on weighted averaging partial least-squares (WAPLS) regression is presented and performs well under cross-validation (r(2)(apparent)= 0.76, RMSE = 4.29; r(2)(jack)= 0.68, RMSEP =5.18). The transfer function was applied to a 1-m peat core, and sample-specific reconstruction errors were generated using bootstrapping. The reconstruction generally suggests near-surface water tables over the last 3,000 years, with a shift to drier conditions at c. cal. 1218-1273 AD.
Assuntos
Amoeba/crescimento & desenvolvimento , Sphagnopsida/microbiologia , Microbiologia da Água , Áreas Alagadas , Amoeba/classificação , Amoeba/isolamento & purificação , Monitoramento Ambiental , Água Subterrânea , Hidrologia , Modelos Teóricos , Peru , Dinâmica Populacional , SoloRESUMO
SUMMARY The survey was carried out to investigate the presence of potentially pathogenic free-living amoebae (FLA) during flood in Chiang Mai, Thailand in 2011. From different crisis flood areas, seven water samples were collected and tested for the presence of amoebae using culture and molecular methods. By monoxenic culture, FLA were detected from all samples at 37 °C incubation. The FLA growing at 37 °C were morphologically identified as Acanthamoeba spp., Naegleria spp. and some unidentified amoebae. Only three samples (42.8%), defined as thermotolerant FLA, continued to grow at 42 °C. By molecular methods, two non-thermotolerant FlA were shown to have 99% identity to Acanthamoeba sp. and 98% identity to Hartmannella vermiformis while the two thermotolerant FLA were identified as Echinamoeba exundans (100% identity) and Hartmannella sp. (99% identity). This first report of the occurrence of FLA in water during the flood disaster will provide information to the public to be aware of potentially pathogenic FLA. .
RESUMO A pesquisa foi feita para investigar a presença de amebas de vida livre (FLA) durante a inundação em Chiang Mai, Tailândia, ano de 2011. A partir de diferentes áreas de inundação sete amostras de água foram coletadas e testadas para a presença de amebas usando métodos moleculares e de cultura. Através da cultura monoxênica, FLA foi detectada em todas as amostras após incubação a 37 °C. As FLA crescendo a 37 °C foram identificadas morfologicamente como Acanthamoeba spp, Naegleria spp e algumas amebas não determinadas. Somente três amostras (42,8%) definidas como FLA termotolerantes continuaram a crescer a 42 °C. Por métodos moleculares duas FLA termotolerantes tiveram 99% de identidade com a Acanthamoeba sp e 98% de identidade com Hartmannella vermiformis enquanto as duas FLA termotolerantes foram identificadas como Echinamoeba exundans (100% de identidade) e Hartmannella sp (99% de identidade). Este primeiro relato da ocorrência de FLA em águas durante inundações informa ao público que ele deve estar atento de FLA potencialmente patogênica. .
Assuntos
Amoeba/genética , Desastres , Inundações , Água/parasitologia , Amoeba/classificação , Amoeba/isolamento & purificação , Amoeba/patogenicidade , Filogenia , Reação em Cadeia da Polimerase , TailândiaRESUMO
The survey was carried out to investigate the presence of potentially pathogenic free-living amoebae (FLA) during flood in Chiang Mai, Thailand in 2011. From different crisis flood areas, seven water samples were collected and tested for the presence of amoebae using culture and molecular methods. By monoxenic culture, FLA were detected from all samples at 37 °C incubation. The FLA growing at 37 °C were morphologically identified as Acanthamoeba spp., Naegleria spp. and some unidentified amoebae. Only three samples (42.8%), defined as thermotolerant FLA, continued to grow at 42 °C. By molecular methods, two non-thermotolerant FlA were shown to have 99% identity to Acanthamoeba sp. and 98% identity to Hartmannella vermiformis while the two thermotolerant FLA were identified as Echinamoeba exundans (100% identity) and Hartmannella sp. (99% identity). This first report of the occurrence of FLA in water during the flood disaster will provide information to the public to be aware of potentially pathogenic FLA.
Assuntos
Amoeba/genética , Desastres , Inundações , Água/parasitologia , Amoeba/classificação , Amoeba/isolamento & purificação , Amoeba/patogenicidade , Filogenia , Reação em Cadeia da Polimerase , TailândiaRESUMO
The population of testate amoebas in the soils of pine forests in Mexico has been studied. In total, 68 species, varieties, and types of testate amoebas with cosmopolite distribution were found. The species diversity of the testate population includes hygrophilous species that differ from hygrophilous species with luvisols in higher andosols. Comparative analysis using the results of one available study of soil testate amoebas from Mexico has been carried out [Bonnet, 1977].
Assuntos
Amoeba/classificação , Amoeba/isolamento & purificação , Ecossistema , Pinus , Árvores , Animais , Biodiversidade , México , Solo , Especificidade da EspécieRESUMO
PURPOSE OF REVIEW: Balamuthia mandrillaris infection of the skin and central nervous system has been increasingly reported in the last decade, making this entity a genuine emerging disease. The ability of the clinician in recognizing the skin lesion early in the course of the disease may lead to a successful therapeutic intervention in an otherwise fatal disease. RECENT FINDINGS: In the past years, advances have been made regarding knowledge about the ubiquity of the ameba in the environment, its worldwide distribution (with higher prevalence in South America), the patients at risk (particularly those of Hispanic origin), the diagnostic methods (including those based on molecular biology) and the different therapeutic strategies that have resulted in survival of patients. A recent report dealing with organ transplant transmission of this infection has made it a subject of interest in transplant medicine. SUMMARY: The present review will allow readers from different fields (clinician, dermatologist, neurologist, infectious disease and transplant specialist) to become familiar with the clinical aspect of the disease, including diagnosis and therapy.
Assuntos
Amebíase/epidemiologia , Antiprotozoários/uso terapêutico , Infecções Protozoárias do Sistema Nervoso Central/epidemiologia , Dermatopatias Parasitárias/epidemiologia , Amebíase/diagnóstico , Amebíase/tratamento farmacológico , Amoeba/isolamento & purificação , Animais , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico , Infecções Protozoárias do Sistema Nervoso Central/tratamento farmacológico , Doenças Transmissíveis Emergentes/epidemiologia , Humanos , Hospedeiro Imunocomprometido , Dermatopatias Parasitárias/diagnóstico , Dermatopatias Parasitárias/tratamento farmacológicoRESUMO
The present work focuses on 12 taxa of the genus Centropyxis Stein, 1857 to explore the conflict between traditional and contemporary taxonomic practices. We examined the morphology, biometry, and ecology of 2,120 Centropyxis individuals collected from Tiete River, Sao Paulo, Brazil; with these new data we studied the consistency of previously described species, varieties, and forms. We encountered transitional forms of test morphology that undermine specific and varietal distinctions for three species and nine varieties. Biometrical analyses made comparing the organisms at the species level suggest a lack of separation between Centropyxis aculeata and Centropyxis discoides, and a possible distinction for Centropyxis ecornis based on spine characteristics. However, incongruence between recent and previous surveys makes taking any taxonomic-nomenclatural actions inadvisable, as they would only add to the confusion. We suggest an explicit and objective taxonomic practice in order to enhance our taxonomic and species concepts for microbial eukaryotes. This will allow more precise inferences of taxon identity for studies in other areas.
Assuntos
Amoeba/classificação , Amoeba/ultraestrutura , Água Doce/parasitologia , Amoeba/isolamento & purificação , Animais , Biometria , Brasil , Microscopia Eletrônica de Varredura , RiosRESUMO
Enteroparasites in children from three marginal urban districts of Trujillo (Peru) were studied to treat these children and to design a prevention and control programme. A total of 845 children were examined. The general prevalence of enteroparasites was of 66.3%, and 45.6% were multiparasitized. The pathogenic enteroparasite prevalence were 23.8% (Giardia lamblia), 4.6% (Iodamoeba buschlii), 2.6% (Cyclospora cayetanensis), 2.2% (Hymenolepis nana), and 2% (Cryptosporidium spp.). G. lamblia was the most frequent parasite both in diarrheic children (28.1%) as well as in nondiarrheic ones (19.5%). The G. lamblia genotypes were molecularly characterized by sequence analysis of the glutamate dehydrogenase (gdh) gene using PCR and RFLP. Sequence analysis revealed both Assemblage A (AI and AII) and Assemblage B (BIV), with the predominance of Assemblage AI. All the samples with Assemblage A were diarrheic but not those with Assemblage B. This is the first study of molecular characterization of G. lamblia in Peruvian children and confirms the importance of asymptomatic patients in the transmission of the giardiosis, especially in places with poor hygiene and sanitation.
Assuntos
Giardia lamblia/isolamento & purificação , Giardíase/epidemiologia , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Amoeba/isolamento & purificação , Animais , Criança , Pré-Escolar , Cyclospora/isolamento & purificação , DNA de Protozoário/análise , DNA de Protozoário/isolamento & purificação , Diarreia/epidemiologia , Diarreia/parasitologia , Genótipo , Giardia lamblia/classificação , Giardia lamblia/enzimologia , Giardia lamblia/genética , Giardíase/parasitologia , Glutamato Desidrogenase/genética , Humanos , Hymenolepis/isolamento & purificação , Enteropatias Parasitárias/fisiopatologia , Peru/epidemiologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência , População UrbanaRESUMO
A study on the presence of free-living amoebae in a public hospital was developed in the city of Porto Alegre, State of Rio Grande do Sul. Dust and biofilms were collected using sterile swabs that had been prepared for this study, from 15 hospital environments, including the intensive care center, pediatric intensive care unit, kitchen, emergency room, outpatient surgical center, clinical surgical center, water storage tanks, taps and six drinking fountains for general use, every month from July 2004 to March 2005. The FLAs were isolated by culturing, using non-nutrient agar medium with the addition of heat-killed Escherichia coli. The protozoa were identified by morphological observation of cysts and trophozoites, in accordance with Page's morphological criteria (1988). Among the 135 samples collected from the 15 environments, 47 (35%) were positive for FLAs. Of these, thirty-four percent presented morphological characteristics particular to the genus Acanthamoeba.
Assuntos
Acanthamoeba/isolamento & purificação , Amoeba/isolamento & purificação , Biofilmes , Poeira , Acanthamoeba/fisiologia , Amoeba/classificação , Amoeba/fisiologia , Animais , Brasil , Hospitais Públicos , HumanosRESUMO
Um estudo sobre a presença de amebas de vida livre em um hospital público foi desenvolvido na Cidade de Porto Alegre, RS. Poeira e biofilmes de 15 ambientes hospitalares, incluindo CTI, UTI pediátrica, cozinha, emergência, centro cirúrgico ambulatorial e centro cirúrgico, reservatórios de água, torneira e 6 bebedouros coletivos foram coletados mensalmente, de julho de 2004 a março de 2005, usando-se suabes estéreis, preparados para a pesquisa. As AVL foram isoladas em cultivo, utilizando-se meio de ágar não nutriente adicionado de Escherichia coli, mortas pelo calor. A identificação dos protozoários foi feita pela observação morfológica de cistos e trofozoítos, segundo critérios morfológicos de Page (1988). Das 135 amostras coletadas dos 15 ambientes estudados, 47 (35 por cento) foram positivas para AVL. Destas, 34 por cento apresentaram características morfológicas próprias do gênero Acanthamoeba.
A study on the presence of free-living amoebae in a public hospital was developed in the city of Porto Alegre, State of Rio Grande do Sul. Dust and biofilms were collected using sterile swabs that had been prepared for this study, from 15 hospital environments, including the intensive care center, pediatric intensive care unit, kitchen, emergency room, outpatient surgical center, clinical surgical center, water storage tanks, taps and six drinking fountains for general use, every month from July 2004 to March 2005. The FLAs were isolated by culturing, using non-nutrient agar medium with the addition of heat-killed Escherichia coli. The protozoa were identified by morphological observation of cysts and trophozoites, in accordance with Page's morphological criteria (1988). Among the 135 samples collected from the 15 environments, 47 (35 percent) were positive for FLAs. Of these, thirty-four percent presented morphological characteristics particular to the genus Acanthamoeba.
Assuntos
Humanos , Animais , Acanthamoeba/isolamento & purificação , Amoeba/isolamento & purificação , Biofilmes , Poeira , Amoeba/classificação , Brasil , Hospitais PúblicosRESUMO
The case of a 7 month-old baby boy is presented, with a history of several weeks of evolution of personality changes, convulsions and fever. While he was hospitalized, the brain image study showed multifocal cavity lesions, which varied from millimeters to 4 cm of diameter, not producing mass effect. Their biopsy revealed necrotizing encephalitis. In spite of treatment, the lesions progressed and the boy died. The autopsy demonstrated an extensive necrotizing encephalitis with fibrinoid necrotic arteritis, signs of organization, and the presence of parasitic elements with characteristics of trophozoites and cysts of free-living amoebas belonging to the genus Acanthamoeba or Balamuthia. In addition, hypoplasia-dysplasia of the thymus and signs of shock were found. The morphologic elements correspond to the disease described as granulomatous amebic encephalitis and the agent found was identified as Balamuthia mandrillaris (Centers for Diseases Control and Prevention, Atlanta, USA ).
Assuntos
Amebíase/parasitologia , Amoeba/isolamento & purificação , Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Encefalite/parasitologia , Granuloma/parasitologia , Amebíase/epidemiologia , Amebíase/patologia , Amoeba/classificação , Animais , Infecções Protozoárias do Sistema Nervoso Central/epidemiologia , Infecções Protozoárias do Sistema Nervoso Central/patologia , Chile , Encefalite/epidemiologia , Encefalite/patologia , Evolução Fatal , Granuloma/epidemiologia , Granuloma/patologia , Humanos , Lactente , MasculinoRESUMO
The free-living amebas Naegleria and Acanthamoeba are recognized as causal agents of central nervous system infections. Recently a third free-living ameba, Balamuthia mandrillaris, was identified as the causal agent of granulomatous encephalitis in humans. We report a case of Balamuthia encephalitis in an immunocompetent school-age girl who presented cutaneous lesions that compromised the central portion of the face. The skin biopsy revealed granulomatous lesion with positive PCR for non-tuberculous Mycobacterium. We started treatment for atypical extrapulmonary mycobacteriosis. Nevertheless, the child was readmitted six months later, with progressive neurological involvement, dying about one year after the onset of cutaneous symptoms. The brain necropsy showed the presence of B. mandrillaris cysts and trophozoites. Balamuthia mandrillaris infection should be considered in the differential diagnosis of a patient with chronic granulomatous disease with neurologic symptoms.
Assuntos
Amebíase/parasitologia , Amoeba/isolamento & purificação , Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Granuloma/parasitologia , Meningoencefalite/parasitologia , Dermatopatias Parasitárias/parasitologia , Amebíase/patologia , Amoeba/classificação , Animais , Infecções Protozoárias do Sistema Nervoso Central/patologia , Pré-Escolar , Evolução Fatal , Feminino , Granuloma/patologia , Humanos , Hospedeiro Imunocomprometido , Meningoencefalite/patologia , Dermatopatias Parasitárias/patologiaRESUMO
We present four cases of cerebral amebae infection treated at our neurosurgical department. Patient 1 was a 12-year-old male with skin lesions of 2 years' progression involving the midface. He received a corticosteroid course, and, after that, he presented a right body hemiparesis. Patient 2 was a 5-year-old male, with a past surgical history of fibula fracture and osteomyelitis of 1-year evolution, associated with lesions of the surrounding skin that presented with partial seizures. Patient 3 was a 3-year-old female who presented with a stroke-like episode and with partial seizures. Patient 4 was a 6-year-old male who had ulcerative lesions in the face of 1-year evolution. After a corticosteroid course, he presented with right-body hemiparesis. All patients were human immunodeficiency virus-negative and died 1 month or less after surgery because of progressive evolution of the disease. Histopathology revealed granulomatous amebic encephalitis. All patients revealed infection from Balamuthia mandrillaris (Leptomyxiidae). Treatment consisting of pentamidine, clarithromycin, fluconazole, and 5-fluorocytosine was ineffective. Although extremely uncommon, granulomatous amebic encephalitis should be considered in the differential diagnosis of cerebral lesions while nonspecific, associated granulomatous skin lesions support the diagnosis of amebiasis.