ABSTRACT
Naegleria fowleri, Acanthamoeba spp. y Balamuthia mandrillaris, son especies de ameba de vida libre (AVL) que causan enfermedades en el sistema nervioso central grave y puede ser fatal en humanos y otros animales. Todos los géneros de AVL tienen dos etapas: quiste y trofozoíto. Los trofozoítos se dividen por fisión binaria, se alimentan activamente y es la etapa infecciosa del organismo. En el medio ambiente, los acanthopodios permiten que los trofozoítos se adhieran a las superficies de las bacterias, hongos, algas y detritos en los que se encuentran su alimento. Acanthamoeba spp. Parecen mantener una relación endosimbiótica con algunas de las bacterias que consumen. Muchas de estas bacterias, como la Legionella, Pseudomonas, Vibrio y algunas micobacterias parecen adquirir factores de virulencia mientras están viviendo dentro de las amebas, lo que les permite sobrevivir y prosperar dentro de otras células fagocíticas (por ejemplo, macrófagos humanos). La tenacidad de AVL para proliferar en ecosistemas hostiles y sobrevivir a la desecación o desinfección hace de estos organismos una fuente potencial transmitida por el agua, por los alimentos y el aire. Conocidos por su ubicuidad, los AVL han sido aislados de diversas matrices ambientales, como suelo, agua dulce y salobre, aguas residuales, aguas termales, polvo y otros. En función de lo antes comentado, este trabajo tiene como objetivo identificar amebas de vida libre en tanques de almacenamiento de agua de edificios del área metropolitana de la ciudad de Ambato (Ecuador), con el fin de aplicar soluciones correctivas en cualquiera de sus puntos. Según el sitio de muestreo, el género de AVL identificado con mayor frecuencia en la superficie fue Balamuthia sp (70,59%) y Acanthamoeba sp., con un 37,78 %. El fondo estuvo caracterizado por Naegleria sp. con un 44,44%(AU)
Naegleria fowleri, Acanthamoeba spp. and Balamuthia mandrillaris are species of free-living amoeba (FLA) that cause severe central nervous system disease and can be fatal in humans and other animals. All genera of FLA have two stages: cyst and trophozoite. Trophozoites divide by binary fission, actively feed, and is the infective stage of the organism. In the environment, acanthopods allow trophozoites to adhere to the surfaces of bacteria, fungi, algae, and detritus on which their food is found. Acanthamoeba spp. they appear to maintain an endosymbiotic relationship with some of the bacteria they consume. Many of these bacteria, such as Legionella, Pseudomonas, Vibrio, and some mycobacteria appear to acquire virulence factors while living inside amoebas, allowing them to survive and thrive inside other phagocytic cells (eg, human macrophages). FLA's tenacity to proliferate in hostile ecosystems and survive desiccation or disinfection makes these organisms a potential waterborne, foodborne, and airborne source. Known for their ubiquity, FLAs have been isolated from various environmental matrices, such as soil, fresh and brackish water, wastewater, hot springs, dust, and others. Based on the aforementioned, this work aims to identify free-living amoebas in water storage tanks of buildings in the metropolitan area of the city of Ambato (Ecuador), in order to apply corrective solutions at any of its points. According to the sampling site, the FLA genus most frequently identified on the surface was Balamuthia sp (70.59%) and Acanthamoeba sp., with 37.78 %. The background was characterized by Naegleria sp. with 44.44%(AU)
Subject(s)
Animals , Acanthamoeba , Naegleria , EcuadorABSTRACT
Resumen El objetivo del estudio fue comparar la extracción de ADN de quistes de Acanthamoeba sp. con un método disponible comercialmente y cuatro no comerciales utilizando tratamiento térmico y ultrasonido para la amplificación por una reacción en cadena de la polimerasa (PCR) convencional, reduciendo tiempos de preparación y extracción de las muestras, como una herramienta para el diagnóstico en el laboratorio clínico. Se utilizó una cepa de Acanthamoeba, genotipo T4, cultivada en agar no nutritivo. Los quistes para analizar, en tres períodos de enquistamiento, se almacenaron a temperatura ambiente. Se extrajo ADN mediante cinco métodos: pretratamiento térmico, ultrasonido y combinaciones de ellos. La PCR se llevó a cabo utilizando cebadores específicos JDP1/JDP2. La concentración y pureza del ADN extraído con los protocolos evaluados revelaron diferencias estadísticamente significativas (p<0,0001). El método E (comercial), el A (térmico) y el B (ultrasonido) lograron los mejores rendimientos en la amplificación del fragmento específico de Acanthamoeba sp. por la PCR convencional.
Abstract The objective of the study was to compare the DNA extraction of Acanthamoeba sp. cysts with a commercially available method and four non-commercial ones, with heat and ultrasound treatment that allows amplification by conventional polymerase chain reaction (PCR), reducing sample preparation and extraction times, such as a tool for diagnosis in the clinical laboratory. To this aim, a strain of Acanthamoeba T4 grown on non-nutrient agar was used. Plates with cysts at three different encystation times were stored at room temperature until the study was carried out. DNA was extracted with five methods that included pretreatments (thermal and ultrasound) or combinations of them. PCR was performed using specific primers JDP1/JDP2. Concentration and purity of DNA revealed statistically significant differences (p<0.0001) between methods. Method E (commercial), method A (thermal) and B (ultrasound) got the best yields in amplifying the specific fragment of Acanthamoeba sp. by conventional PCR.
Resumo O objetivo do estudo foi comparar a extração de DNA de cistos de Acanthamoeba sp. com um método comercialmente disponível e quatro não comerciais utilizando tratamento térmico e ultrassom para amplificação por reação em cadeia da polimerase (PCR) convencional, reduzindo os tempos de preparo e extração das amostras, como ferramenta para o diagnóstico no laboratório clínico. Foi utilizada uma cepa de Acanthamoeba, genótipo T4, cultivada em ágar não nutritivo. Os cistos para analisar foram armazenados em temperatura ambiente, correspondendo a três períodos de encistamento. O DNA foi extraído por cinco métodos: pré-tratamento térmico, ultrassom e combinações deles. A PCR foi realizada usando iniciadores específicos JDP1/JDP2. A concentração e a pureza do DNA extraído com os protocolos avaliados revelaram diferenças estatisticamente significativas (p<0,0001). Os métodos E (comercial), A (térmico) e B (ultrassom) alcançaram os melhores rendimentos na amplificação do fragmento específico de Acanthamoeba sp. por PCR convencional.
Subject(s)
Humans , Infant, Newborn , Infant , Child, Preschool , Child , DNA , Acanthamoeba , Polymerase Chain Reaction , Parasitology , Temperature , Ultrasonics , Thermic Treatment , Clinical Laboratory Techniques , Cysts , Agar , Laboratories, Clinical , Hot Temperature , Laboratories , MethodsABSTRACT
Objetivo Isolar amebas dos gêneros Acanthamoeba e Naegleria em piscinas de uso coletivo do município de Redenção, Pará, Brasil. Métodos A identificação dessas amebas se deu a partir de amostras retiradas de piscinas de uso coletivo de quatro clubes da cidade. As análises foram realizadas a partir do exame direto a fresco, cultura, análise morfológica após coloração de Gram e teste de exflagelação, seguindo o protocolo descrito por Carlesso, Artuso e Rott. Resultados As amebas de vida livre foram encontradas em 41,67% das amostras, com predomínio das do gênero Acanthamoeba (63,2%) no exame direto a fresco. No clube A, localizado no setor Serrinha, houve predominância dessas amebas em relação às demais (8,34%). As amostras obtidas por swabs apresentaram 73,69% de formas evolutivas em comparação à análise feita apenas na água das piscinas. A confirmação dos gêneros das amebas presentes nas amostras feita através da coloração de Gram encontrou um perfil de identificação diferente, sendo que nesse exame a ameba de gênero Naegleriaspp. se sobressaiu perante a de gênero Acanthamoeba (61,11% e 38,89%, respectivamente). Conclusão Os resultados do estudo confirmam a presença de isolados potencialmente patogênicos de amebas de vida livre em piscinas de uso coletivo, o que pode significar um risco à saúde pública.
Objective To isolate amoebae of the genera Acanthamoeba and Naegleria in swimming pools for collective use in the municipality of Redenção, Pará, Brazil. Methods The identification of these amoebae was determined from samples of swimming pools for collective use in four private clubs in the city. The analysis methodology was performed based on direct fresh examination, culture, morphological analysis after Gram staining and exflagellation test, following the protocol described by Carlesso, Artuso and Rott. Results The frequency of free-living amoebae was 41.67%, with a predominance of the Acanthamoeba genus (63.2%) in direct fresh examination. At club A, located in the Serrinha sector, the frequency of these amoebae was higher than the others (8.34%). The samples obtained by swabs showed 73.69% of evolutionary forms in comparison to the analysis only of the water in the pools. The confirmation of the genera by Gram stain showed a different identification profile, in which Naegleria spp. stood out before the genus Acanthamoeba (61.11% and 38.89%, respectively). Conclusion In conclusion, the results of the study confirm the presence of potentially pathogenic isolates from free-living amoebae in swimming pools for collective use that may present risks to public health.
Subject(s)
Acanthamoeba , Naegleria , Swimming Pools , AmoebaABSTRACT
La encefalitis amebiana granulomatosa es una enfermedad considerada atípica debido a la baja incidencia desde que fue descubierta. Sin embargo, conforme han avanzando los métodos diagnósticos, en retrospectiva, se ha descrito la presencia de esta enfermedad desde principios del siglo XX, identificando a Acanthamoeba spp y Balamuthia mandrillaris como agentes más comunes.Es una enfermedad de difícil diagnóstico debido al amplio abanico clínico que puede presentar, siendo el sitio anatómico dentro del sistema nervioso central quien determinará estas características. El conocimiento y sospecha de la misma permitirá un abordaje terapéutico oportuno aunque, en la mayoría de los casos, con un desenlace fatal para el paciente.A continuación se presenta el caso clínico de un paciente masculino de 26 años de edad originario de la ciudad de Durango, México, sin antecedentes de importancia, de ocupación ladrillero, quien sufre golpe con ladrillo en región naso-orbitaria, ingresando al hospital al tercer día del evento con diagnóstico de celulitis periorbitaria izquierda y nasal, cefalea de leve intensidad, rinorrea abundante, hemiparesia fasciocorporal izquierda, parestesia de extremidad superior izquierda, diplopía y vértigo postural. Los estudios imagenológicos revelaron lesiones heterogéneas en el lóbulo occipital, hemisferio cerebeloso izquierdo y tallo cerebral. Se realizó escisión de lesión tumoral cerebelar, con estudio anatomopatológico, reportando encefalitis granulomatosa por presencia de ameba de vida libre. El paciente evolucionó hacia deterioro rostro-caudal declarándose su fallecimiento a los 16 días de su estancia intrahospitalaria.En el Estado de Durango, México, no se cuenta con casos reportados por infección de ameba de vida libre
Granulomatous amoebic encephalitis is a disease considered atypical due to the low incidence since it was discovered. However, as diagnostic methods have progressed, in retrospect, the presence of this disease has been described since the beginning of the 20th century, identifying Acanthamoeba spp. and Balamuthia mandrillaris as the most common agents.A disease that is difficult to diagnose due to the wide clinical range that it can present, being the anatomical site within the central nervous system that will determine these characteristics. The knowledge and suspicion of it will allow a timely therapeutic approach although, in most cases, with a fatal outcome for the patient.The clinical case is presented below of a 26 year old male patient from the city of Durang, México, with no significant history, of brick occupation, who suffers a blow with a brick in the naso-orbital region, follows, entering our hospital on the third day of the event with a diagnosis of left periorbital and nasal cellulitis, mild headache, profuse rhinorrhea, left fasciocorporeal hemiparesis, left upper limb parestesia, diplopia, and postural vertigo.Imaging studies were performed observing heterogeneous lesions in the occipital lobe, left cerebellar hemisphere and brain stem; excision of the cerebellar tumor lesion being carried out, with pathological study, reporting granulomatous encephalitis due to the presence of free-living amoeba. The patient progresses to face-caudal deterioration, declaring his death after 16 days of hospital stay.Within the state of Durango, Mexico, there are no reported cases of free-living amoeba infection
Subject(s)
Male , Encephalitis , Acanthamoeba , Balamuthia mandrillaris , Headache , AmoebaABSTRACT
Las amebas de vida libre (AVL) son parásitos protozoarios que ocasionalmente causan enfermedad en humanos luego del contacto con alguna fuente de aguas o suelo contaminado. Se describe una serie de tres casos de encefalitis con desenlace fatal en un grupo familiar, que tuvo lugar en el departamento de Tumbes entre diciembre de 2019 y febrero de 2020. En la muestra de líquido cefalorraquídeo del primer caso se identificó Acanthamoeba sp. Los tres casos presentaron como antecedente haber entrado a una piscina meses antes de la enfermedad. En Tumbes no hay registro previo de casos de encefalitis por AVL y no se han reportado a nivel mundial su ocurrencia en un conglomerado familiar.
Free-living amoebas (FLA) are protozoan parasites that occasionally cause disease in humans after contact with contaminated water or soil. We describe a series of three cases of encephalitis in a family group with a fatal outcome that occurred in the Tumbes region between December 2019 and February 2020. Acanthamoeba sp. was identified in the cerebrospinal fluid sample from case 1. All three cases had a history of entering a swimming pool months before the disease. In the Tumbes region there is no previous record of encephalitis due to FLA and its occurrence in a family cluster has never been reported before.
Subject(s)
Humans , Male , Brain Diseases , Acanthamoeba , Central Nervous System Protozoal InfectionsABSTRACT
Introducción: Las amebas de vida libre (AVL) Naegleria fowleri, Acanthamoeba spp., Balamuthia mandrillaris, son protozoos ampliamente distribuidos en la naturaleza. Son microorganismos oportunistas, que afectan preferentemente al sistema nervioso central causando cuadros de meningoencefalitis amebiana primaria o de encefalitis granulomatosa amebiana (EGA), ambas patologías de alta mortalidad. Descripsión del Caso: Paciente femenina de 10 años, que ingresa a nuestro hospital por presentar hemiparesia braquiocrural izquierda, vómitos y cefalea de 72 horas de evolución. Se realiza tomografía computada y Resonancia Magnética en la que se identifica una lesión expansiva, sólido-quística ubicada en la región fronto derecha. Se realiza exéresis completa de la misma y se implementa tratamiento farmacológico lográndose la restitución ad-integrum de la función motora y la resolución de la EGA a 30 meses de seguimiento. Discusión: La encefalitis granulomatosa amebiana es una patología causada por amebas de vida libre. Su presentacíon clínica puede ser indistinguible de otras causas de leptomeningitis o encefalitis, como las de origen bacteriano, viral o por micobacterias lo que impide conocer su real incidencia. Su tratamiento antiparasitario es muy complejo y su evolución es habitualmente fatal. Conclusión: Reportamos un caso de Encefalitis Amebiana Granulomatosa en una paciente pediátrica inmunocompetente, con excelente evolución.
Introduction: Free-living amoebas (FLA) Naegleria fowleri, Acanthamoeba spp., and Balamuthia mandrillaris, are protist widely distributed in nature. Are opportunistic microorganisms, preferentially affect the central nervous system causing primary amoebic meningoencephalitis or amoebic granulomatous encephalitis (AGE), both with high mortality. Case report: A 10 year-old female patient was admitted with a three-day history of left hemiparesis accompanied with headaches and vomiting. Computed tomography and magnetic resonance were performed, in which an expansive solid cystic mass was observed in the right fronto-parietal region. Complete resection was performed and pharmacological treatment was started, achieving complete restitution of motor function and resolution of AGE after 30 months of follow-up. Discussion: AGE is a desease caused by free-living amoebas. Its clinical presentation is similar to other leptomeningitis or encephalitis of different etiology such as bacterial, viral or by mycobacterial, which cannot know its real incidence. Its pharmacological treatment is complex and its evolution is usually fatal. Conclusion: We report a case of Amoebic Granulomatous Encephalitis in an immunocompetent pediatric patient with good outcome.
Subject(s)
Encephalitis , Pediatrics , Acanthamoeba , TomographyABSTRACT
Background and Objectives: Acanthamoeba are among the most prevalent environmental protozoans and have a cosmopolitan distribution. The main concern in public health is that they can also be isolated from contact lenses, storage cases and cleaning solutions, ventilation and air conditioning systems, dental treatment units, dialysis units, emergency showers and eyewash stations. As these genera include a diversity of pathogenic microorganisms that leads to infectious diseases inside the hospital environment, it is of the utmost importance to carry out the surveillance, considering mainly the immunocompromised patients, who are more susceptible to these diseases. The level of human health risk and its associations in the hospital environment are unknown, and part of this problem is potentially the lack of correlation between protozoan exposure and the onset of symptoms that can occur in each patient at different periods in time. Thus, this review offers a current overview of the presence of Acanthamoeba spp. in hospital environments with the aim to detect its presence in these environments. Methods: This is a review of the literature on Lilacs, Scielo, Medline and Bdenf databases to gather and synthesize publications and search for effective ways of controlling the presence of Acanthamoeba through disinfection and monitoring measures. Results: We found that Acanthamoeba is present in different hospital environments, namely in water, dust, biofilm, cooling waters and air conditioners. Conclusion: Studies on the ecology and distribution of non-enteric pathogens in the hospital environment are necessary for understanding their potential threat to human health.(AU)
Justificativa e objetivos: Acanthamoeba estão entre os protozoários ambientais mais prevalentes e possuem distribuição cosmopolita. A principal preocupação para fins de saúde pública é que eles também podem ser isolados de lentes de contato, caixas de armazenamento e soluções de limpeza, sistemas de ventilação e ar condicionado, unidades de tratamento odontológico, unidades de diálise, chuveiros de emergência e lava-olhos. O gênero Acanthamoeba compreende várias espécies que podem determinar doenças infecciosas dentro do ambiente hospitalar, e é de suma importância realizar a vigilância, considerando principalmente os pacientes imunocomprometidos, que são mais suscetíveis a essas doenças. O nível de risco para a saúde humana e suas associações no ambiente hospitalar é desconhecido, e parte desse problema ocorre pela falta de correlação entre a exposição ao protozoário e o início dos sintomas, que cada paciente pode desenvolver em diferentes períodos. Assim, esta revisão apresenta uma visão geral atual de Acanthamoeba spp. em ambientes hospitalares, com o objetivo de verificar sua presença nesses ambientes. Métodos: Trata-se de uma revisão da literatura nas bases Lilacs, Scielo, Medline e Bdenf para reunir e sintetizar publicações e buscar formas eficazes de controle de sua presença por meio de medidas de desinfecção e monitoramento. Resultados: Verificamos que Acanthamoeba está presente em diferentes ambientes hospitalares, estando presente em água, poeira, biofilme, águas de refrigeração e ar condicionados. Conclusão: Estudos sobre a ecologia e distribuição de patógenos não-entéricos no ambiente hospitalar são necessários para entender sua ameaça potencial à saúde humana.(AU)
Justificativa y Objetivos: Acanthamoeba están entre los protozoos ambientales más prevalentes y poseen una distribución cosmopolita. La principal preocupación por la salud pública es que también pueden aislarse de lentes de contacto, cajas de almacenamiento y soluciones de limpieza, sistemas de ventilación y aire acondicionado, unidades de tratamiento odontológico, unidades de diálisis, duchas de emergencia y lava- los ojos. Estos géneros incluyen una diversidad de microorganismos patógenos que conducen a enfermedades infecciosas dentro del ambiente hospitalario, y es de suma importancia realizar la vigilancia, considerando principalmente a los pacientes inmunocomprometidos, que son más susceptibles a esas enfermedades. El nivel de riesgo para la salud humana y sus asociaciones en el ambiente hospitalario es desconocido, y parte de este problema es potencialmente la falta de correlación entre la exposición al protozoario y el inicio de los síntomas, que cada paciente puede desarrollar en diferentes períodos en el tiempo. Así, esta revisión presenta una visión general actual de la presencia de Acanthamoeba spp. en ambientes hospitalarios, con el objetivo de verificar su presencia en esos ambientes. Métodos: Se trata de una revisión de la literatura en las bases Lilacs, Scielo, Medline y Bdenf para reunir y sintetizar publicaciones y buscar formas eficaces de control de su presencia por medio de medidas de desinfección y monitoreo. Resultados: En el presente trabajo se analizan los resultados de la evaluación de la calidad de los alimentos y de los productos alimenticios en el medio ambiente hospitalario, que se encuentran en el agua, polvo, biofilm, aguas de refrigeración y aire acondicionados. Conclusión: Estudios sobre la ecología y distribución de patógenos no entéricos en el ambiente hospitalario son necesarios para entender su amenaza potencial salud humana.(AU)
Subject(s)
Acanthamoeba , HospitalsABSTRACT
RESUMEN Se reporta el uso del crosslinking como tratamiento de la queratitis por Acanthamoeba en una serie de 7 pacientes quienes acudieron al Servicio de Córnea por queratitis multitratadas. Se les realizó biopsia corneal, la cual se cultivó en solución de Page. Los pacientes fueron tratados con un protocolo de PACK-CXL durante más de 5 minutos y fueron sometidos a la exposición a la luz UV-A. El edema del nuevo epitelio era de 2 cruces a las 24 horas, y desapareció a las dos semanas del procedimiento en todos los casos. El porcentaje de desepitelización basal al momento del diagnóstico fue de 75,7 por ciento. La agudeza visual mejor corregida fue de entre 20/20 y 20/30. Se concluye que el uso de crosslinking en pacientes con Acanthamoeba en fases inicales pudiera ser una opción terapéutica segura y efectiva(AU)
ABSTRACT A report is presented of the use of crosslinking as treatment for Acanthamoeba keratitis in a series of 7 patients attending the Cornea Service for multitreated keratitis. Corneal biopsy was performed, which was cultured in Page solution. The patients were treated with a PACK-CXL protocol for more than 5 minutes and subjected to UV-A light exposure. Edema of the new epithelium was 2 crosses at 24 hours and disappeared 2 weeks after the procedure in all cases. Basal de-epithelialization percentage at diagnosis was 75.7 percent. Best corrected visual acuity ranged between 20/20 and 20/30. It is concluded that the use of crosslinking in patients with Acanthamoeba keratitis in its initial stages could be a safe and effective therapeutic option(AU)
Subject(s)
Humans , Adult , Middle Aged , Aged , Acanthamoeba/cytology , Acanthamoeba Keratitis/diagnosis , Acanthamoeba Keratitis/drug therapy , Research Report , Review Literature as Topic , Databases, BibliographicABSTRACT
RESUMEN Objetivo: Estandarizar una técnica de reacción en cadena de la polimerasa en tiempo real para la detección del parásito e identificar Acanthamoeba en líquidos conservantes de lentes de contacto. Métodos: Se realizó un estudio descriptivo observacional de corte transversal sobre la técnica de reacción en cadena de la polimerasa en tiempo real para la detección de Acanthamoeba, en el Instituto de Investigaciones en Ciencias de la Salud de la ciudad de Asunción, en Paraguay. Se analizaron 110 líquidos conservantes aportados por usuarios sanos de lentes de contacto, mediante reacción en cadena de la polimerasa en tiempo real y cultivo en medio PAGE - SDS. Resultados: Se estandarizó con éxito la técnica de reacción en cadena de la polimerasa en tiempo real con límite de sensibilidad de 1 pg/µL. Se aisló Acanthamoeba a partir de una muestra (1 por ciento) por método de cultivo, mientras que la carga parasitaria en el líquido conservante fue inferior al límite de detección de la reacción en cadena de la polimerasa en tiempo real. El ADN obtenido del cultivo de dicha muestra fue positivo para Acanthamoeba por este método. Conclusión: El sistema estandarizado presenta buena sensibilidad y podrá ser incorporado en los laboratorios que cuentan con acceso a equipos de reacción en cadena de la polimerasa en tiempo real para un diagnóstico rápido y más eficiente en casos de sospechas de queratitis amebiana. Recomendamos el uso combinado de métodos moleculares y cultivo para aumentar la potencia del diagnóstico, sobre todo en muestras donde la carga parasitaria es muy baja(AU)
ABSTRACT Objective: Standardize a real-time polymerase chain reaction technique for detection of the parasite and identify Acanthamoeba in contact lens solutions. Methods: A cross-sectional observational descriptive study was conducted about a real-time polymerase chain reaction technique for detection of Acanthamoeba at the Institute of Health Sciences Research in the city of Asunción, Paraguay. A total 110 solutions were analyzed, which were provided by healthy contact lens users, by real-time polymerase chain reaction and culture in SDS-PAGE medium. Results: Successful standardization was achieved of the real-time polymerase chain reaction technique with a sensitivity limit of 1 pg/µl. Acanthamoeba was isolated from one sample (1 percent) by culture, whereas the parasite load in the contact lens solution was below the detection limit of the real-time polymerase chain reaction technique. The DNA obtained from the culture of that sample was positive for Acanthamoeba by the real-time polymerase chain reaction technique method. Conclusion: The system standardized exhibits good sensitivity and may be incorporated into laboratories with real-time polymerase chain reaction technique equipment for a rapid and more efficient diagnosis of suspected amoebic keratitis. We recommend the combined use of molecular methods and culture to enhance diagnostic power, mainly in samples where the parasite load is very low(AU)
Subject(s)
Humans , Acanthamoeba/microbiology , Acanthamoeba Keratitis/etiology , Contact Lenses/adverse effects , Real-Time Polymerase Chain Reaction/methods , Epidemiology, Descriptive , Cross-Sectional Studies , Contact Lens Solutions/therapeutic use , Observational Studies as TopicABSTRACT
Abstract Purpose: To compare clinical-epidemiological profile and treatment outcome between culture negative and culture positive keratitis patients. Methods: Patients with suspected infectious keratitis seen at two ophthalmic hospitals in Curitiba, Brazil, between June 2014 and April 2016, were prospectively studied. Ophthalmological exam with corneal scraping and microbiological tests were performed. Data regarding follow up, surgical interventions and treatment outcome were collected after 12 weeks of the first visit trough medical chart review. From the results of the culture, two groups were formed: culture negative keratitis (CNK) and culture positive keratitis (CPK). Results: According to inclusion criteria 21 patients were classified as culture negative keratitis and 20 patients as culture positive keratitis. The number of patients on antibiotic drops at the first visit was greater in CNK group (90.5% versus 60%; p=0.032). Surgical procedures were necessary in 3 patients (15%) in CNK group and in 7 patients (36,8%) in CPK group (p=0.155). Treatment success was achieved by 85% (17/20) of the patients in CNK group and by 61% (11/18) of the patients in CPK group (p=0.144). There was no significant difference between groups regarding age, gender, place of residence, presence of comorbidities, risk factors for infectious keratitis, duration of symptoms and characteristics of corneal ulcer. Conclusions: Previous treatment with antibiotics correlates with negative culture results. There was no significant difference in treatment outcome between culture negative and culture positive keratitis patients.
Resumo Objetivo: Comparar os perfis clinico-epidemiológicos e os desfechos entre pacientes com ceratite com cultura positiva e pacientes com ceratite com cultura negativa. Métodos: Pacientes com ceratite infecciosa, atendidos em dois hospitais oftalmológicos em Curitiba, Brasil, entre junho de 2014 e abril de 2016, foram estudados prospectivamente. Exame oftalmológico, raspado de córnea e exames microbiológicos foram realizados no primeiro atendimento. Os dados quanto a seguimento e desfecho foram coletados após 12 semanas do primeiro atendimento através de revisão de prontuário. A partir dos resultados das culturas, dois grupos foram formados: ceratite com cultura negativa e ceratite com cultura positiva. Resultados: Vinte e um pacientes foram classificados como ceratite com cultura negativa e 20 como ceratite com cultura positiva. O número de pacientes em uso de colírio antibiótico no primeiro atendimento foi maior no grupo de cultura negativa (90,5% versus 60%; p=0,032). Sete pacientes (37%) no grupo cultura positiva precisaram de procedimentos cirúrgicos no manejo da ceratite, versus 3 pacientes (15%) do grupo cultura negativa (p=0,155). Oitenta e cinco por cento (17/20) dos pacientes do grupo cultura negativa alcançaram sucesso no tratamento, contra 61% (11/18) dos pacientes no grupo cultura positiva (p=0,144). Não houve diferença entre os grupos quanto a idade, gênero, local de procedência, presença de comorbidades, fatores de risco, duração dos sintomas e características da úlcera de córnea. Conclusão: Tratamento prévio com colírio de antibiótico correlaciona-se com resultados negativos de cultura. Não houve diferença no desfecho após tratamento entre os pacientes com cultura negativa e cultura positiva.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Keratitis/diagnosis , Keratitis/microbiology , Keratitis/parasitology , Keratitis/drug therapy , Keratitis/epidemiology , Bacteria/isolation & purification , Acanthamoeba/isolation & purification , Acanthamoeba Keratitis/diagnosis , Acanthamoeba Keratitis/parasitology , Acanthamoeba Keratitis/drug therapy , Acanthamoeba Keratitis/epidemiology , Eye Infections, Bacterial/diagnosis , Eye Infections, Bacterial/microbiology , Eye Infections, Bacterial/drug therapy , Eye Infections, Bacterial/epidemiology , Eye Infections, Fungal/diagnosis , Eye Infections, Fungal/microbiology , Eye Infections, Fungal/drug therapy , Eye Infections, Fungal/epidemiology , Prospective Studies , Microbiological Techniques/methods , Treatment Outcome , Fungi/isolation & purification , Anti-Bacterial Agents/therapeutic use , Antifungal Agents/therapeutic use , Antiprotozoal Agents/therapeutic useABSTRACT
Resumo Objetivo: A queratite infeciosa é uma doença de incidência relativamente elevada e é responsável por um número importante de internamentos. Neste estudo pretende-se estudar diversas características epidemiológicas e clínicas associadas às queratites infeciosas de alto risco num hospital terciário em Portugal. Métodos: Realizou-se um estudo retrospetivo, onde foram incluídos todos os doentes internados por abcesso da córnea no Centro Hospitalar Universitário do Porto (CHUP), entre Abril de 2013 a Março de 2018. Caracterizou-se a população em relação aos fatores de risco, apresentação clínica, tempo de internamento, resultados de culturas, resistência antibiótica in vitro, tratamento efetuado e resultado funcional. Resultados: O estudo incluiu 105 doentes. Os principais fatores de risco foram antecedentes de cirurgia de córnea, uso de lentes de contacto e história recente de trauma ocular. 74,3% dos doentes tiveram cultura positiva com 87,9% a corresponderem a cultura bacteriana pura, sendo a Pseudomonas aeruginosa e o Streptococcus pneumoniae os agentes etiológicos mais frequentes. 27,9% das culturas positivas eram resistentes a 3 ou mais classes de antibióticos. Todos os doentes iniciaram tratamento com colírios fortificados. 29,5% dos doentes necessitaram de realizar transplante de córnea. Ao final de 6 meses de seguimento, apenas 20,9% apresentavam AV>20/40. Conclusão: Na maioria dos casos, a etiologia foi bacteriana. Observou-se um número considerável de bactérias multirresistentes. Apesar do tratamento ter permitido uma melhoria da visão na maioria dos casos, um número considerável de doentes ficou com sequelas visuais importantes.
Abstract Objective: Infectious keratitis is a pathology with a high incidence and is responsible for a large number of prolonged stay hospital admissions. The purpose was to analyze the epidemiological and clinical data associated with high risk microbial keratitis at a central hospital in Portugal. Methods: A retrospective study of all inpatients presenting with corneal abscess in Centro Hospitalar Universitário do Porto, from April 2013 to March 2018 was performed. Target population was characterized by risk factors, clinical features, length of stay, culture results, in vitro antibiotic resistance, treatment and outcome. Results: This study included 105 patients. The main risk factors were previous corneal surgery, contact lenses wear and recent history of ocular trauma. 74.3% of patients had a positive culture, 87.9% of these corresponding to a pure bacterial culture, with Pseudomonas aeruginosa and Streptococcus pneumoniae being the most common pathogens. 27.9% of positive cultures were resistant to 3 or more classes of antibiotics. All patients began treatment with fortified drops. 29.5% of patients required a corneal transplant. After 6 months of follow-up, only 20.9% presented a VA>20/40. Conclusion: Most cases were caused by bacteria. A considerable number of multi-resistant bacteria was identified. Despite most cases having improved after treatment, a large number of patients had a significant visual acuity sequelae.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Eye Infections, Bacterial/epidemiology , Eye Infections, Fungal/epidemiology , Eye Infections, Parasitic/epidemiology , Eye Infections, Viral/epidemiology , Keratitis/epidemiology , Ophthalmic Solutions , Portugal , Bacteria/isolation & purification , Viruses/isolation & purification , Drug Resistance, Microbial , Acanthamoeba/isolation & purification , Eye Infections, Bacterial/microbiology , Eye Infections, Bacterial/therapy , Eye Infections, Fungal/microbiology , Eye Infections, Fungal/therapy , Eye Infections, Parasitic/microbiology , Eye Infections, Parasitic/therapy , Eye Infections, Viral/microbiology , Eye Infections, Viral/drug therapy , Retrospective Studies , Risk Factors , Corneal Transplantation , Fungi/isolation & purification , Hospitals, University/statistics & numerical data , Inpatients , Keratitis/microbiology , Keratitis/therapyABSTRACT
Acanthamoeba castellanii has ubiquitous distribution and causes primary acanthamoebic keratitis (AK). AK is a common disease in contact lens wearers and results in permanent visual impairment or blindness. In this study, we observed the cytopathic effect, in vitro cytotoxicity, and secretion pattern of cytokines in human corneal epithelial cells (HCECs) induced by A. castellanii trophozoites and/or cysts. Morphological observation revealed that panked dendritic HCECs co-cultured with amoeba cysts had changed into round shape and gradually died. Such changes were more severe in co-culture with cyst than those of co-cultivation with trophozoites. In vitro cytotoxicity assay revealed the highest cytotoxicity to HCECs in the co-culture system with amoeba cysts. A. castellanii induced the expression of IL-1α, IL-6, IL-8, and CXCL1 in HCECs. Secreted levels of IL-1α, IL-6, and IL-8 in HCECs co-cultured with both trophozoites and cysts were increased at an early incubation time (3 and 6 hr). These results suggested that cytopathic changes and pro-inflammatory cytokines release of HCECs in response to A. castellanii, especially amoebic cysts, are an important mechanism for AK development.
Subject(s)
Humans , Acanthamoeba castellanii , Acanthamoeba , Amoeba , Blindness , Coculture Techniques , Cytokines , Epithelial Cells , In Vitro Techniques , Interleukin-6 , Interleukin-8 , Keratitis , Trophozoites , Vision DisordersABSTRACT
Acanthamoeba, one of free-living amoebae (FLA), remains a high risk of direct contact with this protozoan parasite which is ubiquitous in nature and man-made environment. This pathogenic FLA can cause sight-threatening amoebic keratitis (AK) and fatal granulomatous amoebic encephalitis (GAE) though these cases may not commonly be reported in our clinical settings. Acanthamoeba has been detected from different environmental sources namely; soil, water, hot-spring, swimming pool, air-conditioner, or contact lens storage cases. The identification of Acanthamoeba is based on morphological appearance and molecular techniques using PCR and DNA sequencing for clinico-epidemiological purposes. Recent treatments have long been ineffective against Acanthamoeba cyst, novel anti-Acanthamoeba agents have therefore been extensively investigated. There are efforts to utilize synthetic chemicals, lead compounds from medicinal plant extracts, and animal products to combat Acanthamoeba infection. Applied nanotechnology, an advanced technology, has shown to enhance the anti-Acanthamoeba activity in the encapsulated nanoparticles leading to new therapeutic options. This review attempts to provide an overview of the available data and studies on the occurrence of pathogenic Acanthamoeba among the Association of Southeast Asian Nations (ASEAN) members with the aim of identifying some potential contributing factors such as distribution, demographic profile of the patients, possible source of the parasite, mode of transmission and treatment. Further, this review attempts to provide future direction for prevention and control of the Acanthamoeba infection.
Subject(s)
Animals , Humans , Acanthamoeba , Amoeba , Asia, Southeastern , Asian People , Encephalitis , Keratitis , Nanoparticles , Nanotechnology , Parasites , Plants, Medicinal , Polymerase Chain Reaction , Sequence Analysis, DNA , Soil , Swimming Pools , WaterABSTRACT
Acanthamoeba keratitis (AK) is a rare sight-threatening corneal infection, often reporting from contact lens wearers. An asymptomatic human immunodeficiency virus (HIV)-infected Thai male without history of contact lens use complained foreign body sensation at his left eye during motorbike riding. He had neither specific keratitis symptoms nor common drugs responding, which contributed to delayed diagnosis. By corneal re-scraping, Acanthamoeba-like cysts were detected by calcofluor white staining and agar culture. The etiological agent obtained from the culture was molecularly confirmed by Acanthamoeba spp.-specific PCR, followed by DNA sequencing. The results from BLAST and phylogenetic analysis based on the DNA sequences, revealed that the pathogen was Acanthamoeba T4, the major genotype most frequently reported from clinical isolates. The infection was successfully treated with polyhexamethylene biguanide resulting in corneal scar. This appears the first reported AK case from a non-contact lens wearer with HIV infection in Thailand. Although AK is sporadic in developing countries, a role of free-living Acanthamoeba as an opportunistic pathogen should not be neglected. The report would increase awareness of AK, especially in the case presenting unspecific keratitis symptoms without clinical response to empirical antimicrobial therapy.
Subject(s)
Humans , Male , Acanthamoeba Keratitis , Acanthamoeba , Agar , Asian People , Base Sequence , Corneal Injuries , Delayed Diagnosis , Developing Countries , Foreign Bodies , Genotype , HIV Infections , HIV , Keratitis , Off-Road Motor Vehicles , Polymerase Chain Reaction , Sensation , Sequence Analysis, DNA , ThailandABSTRACT
Abstract We report an Acanthamoeba keratitis case associated with the use of contact lens in a 28-year-old female from Brasília, Brazil. Samples from corneal scraping and contact lens case were used for culture establishment, PCR amplification, and partial sequencing (fragments of ~400kb) of small subunit rDNA; both culture and PCR were positive. The sequence analyses of the cornea and of isolates from the contact lens case showed similarity with the T4 genotype. To the best of our knowledge, this is the first report of T4 Acanthamoeba keratitis case from the Midwest region of Brazil.
Subject(s)
Humans , Male , Adult , Acanthamoeba/genetics , Acanthamoeba Keratitis/diagnosis , Contact Lenses/parasitology , Acanthamoeba/isolation & purification , Acanthamoeba Keratitis/surgery , Acanthamoeba Keratitis/etiology , GenotypeABSTRACT
BACKGROUND: This study aimed to evaluate the adhesion of Acanthamoeba trophozoites on cosmetic contact lenses (CLs) with and without CL care multipurpose solution (MPS) treatment. METHODS: Acanthamoeba lugdunensis L3a trophozoites were inoculated onto disks trimmed from CLs: 1-day Acuvue moist, 1-day Acuvue define, Acuvue 2, and Acuvue 2 define. After 18-hour inoculation, the number of adherent trophozoites was counted under phase contrast microscopy. The effects of MPS, Opti-Free Express, soaking CLs for 6 hours, on Acanthamoeba adhesion were analyzed. Scanning electron microscopic examination was performed for assessment of Acanthamoeba attached on the lens surface. RESULTS: Acanthamoeba trophozoites showed greater adhesion to cosmetic CL (P = 0.017 for 1-day CL and P = 0.009 for 2-week CL) although there was no significant difference between the types of cosmetic CL. On all lenses, the number of adherent Acanthamoeba was significantly reduced after treatment with MPS (P < 0.001 for 1-day Acuvue moist, P = 0.046 for 1-day Acuvue define, P < 0.001 for Acuvue 2, and P = 0.015 for Acuvue 2 define), but there was still significant difference between conventional and cosmetic CLs (P = 0.003 for 1-day CL and P < 0.001 for 2-week CL, respectively). More attachment of Acanthamoeba was observed on colored area and the acanthopodia of Acanthamoeba was placed on the rough surface of colored area. CONCLUSION: Acanthamoeba showed a greater affinity for cosmetic CL and mostly attached on colored area. Although MPS that contained myristamidopropyl dimethylamine reduced the adhesion rate, there was a significant difference between conventional and cosmetic CLs.
Subject(s)
Acanthamoeba , Contact Lenses , Microscopy, Phase-Contrast , TrophozoitesABSTRACT
Multipurpose contact lens disinfecting solutions (MPDS) are widely used to cleanse and disinfect microorganisms. However, disinfection efficacy of these MPDS against Acanthamoeba cyst remain insufficient. 2, 6-dichlorobenzonitrile (DCB), a cellulose synthesis inhibitor, is capable of increasing the amoebical effect against Acanthamoeba by inhibiting its encystation. In this study, we investigated the possibility of DCB as a disinfecting agent to improve the amoebicidal activity of MPDS against Acanthamoeba cyst. Eight commercial MPDS (from a to h) were assessed, all of which displayed insufficient amoebicidal activity against the mature cysts. Solution e, f, and h showed strong amoebicidal effect on the immature cysts. Amoebicidal efficacy against mature cysts remained inadequate even when the 8 MPDS were combined with 100 μM DCB. However, 4 kinds of MPDS (solution d, e, f, and h) including 100 μM DCB demonstrated strong amoebicidal activity against the immature cysts. The amoebicidal activity of solution d was increased by addition of DCB. Cytotoxicity was absent in human corneal epithelial cells treated with either DCB or mixture of DCB with MPDS. These results suggested that DCB can enhance the amoebicical activity of MPDS against Acanthamoeba immature cyst in vitro.
Subject(s)
Humans , Acanthamoeba , Cellulose , Disinfection , Epithelial Cells , In Vitro TechniquesABSTRACT
Acanthamoeba spp. are free-living protozoa that are opportunistic pathogens for humans. Cysteine proteases of Acanthamoeba have been partially characterized, but their biochemical and functional properties are not clearly understood yet. In this study, we isolated a gene encoding cysteine protease of A. castellanii (AcCP) and its biochemical and functional properties were analyzed. Sequence analysis of AcCP suggests that this enzyme is a typical cathepsin L family cysteine protease, which shares similar structural characteristics with other cathepsin L-like enzymes. The recombinant AcCP showed enzymatic activity in acidic conditions with an optimum at pH 4.0. The recombinant enzyme effectively hydrolyzed human proteins including hemoglobin, albumin, immunoglobuins A and G, and fibronectin at acidic pH. AcCP mainly localized in lysosomal compartment and its expression was observed in both trophozoites and cysts. AcCP was also identified in cultured medium of A. castellanii. Considering to lysosomal localization, secretion or release by trophozoites and continuous expression in trophozoites and cysts, the enzyme could be a multifunctional enzyme that plays important biological functions for nutrition, development and pathogenicity of A. castellanii. These results also imply that AcCP can be a promising target for development of chemotherapeutic drug for Acanthamoeba infections.
Subject(s)
Humans , Acanthamoeba castellanii , Acanthamoeba , Cathepsin L , Cathepsins , Cysteine Proteases , Cysteine , Fibronectins , Genes, vif , Hydrogen-Ion Concentration , Lysosomes , Sequence Analysis , Trophozoites , VirulenceABSTRACT
Members of genus Acanthamoeba are widely distributed in the environment. Some are pathogenic and cause keratitis and fatal granulomatous amoebic encephalitis. In this study, we isolated an Acanthamoeba CJW/W1 strain from tap water in Wuxi, Jiangsu Province, China. Its 18S rDNA was sequenced and a phylogenetic tree was constructed. The isolated cysts belonged to morphologic group II. Comparison of 18S rDNA sequences of CJW/W1 strain and other isolates showed high similarity (99.7%) to a clinical isolate Asp, KA/E28. A phylogeny analysis confirmed this isolate belonged to the pathogenic genotype T4, the most common strain associated with Acanthamoeba-related diseases. This is the first report of an Acanthamoeba strain isolated from tap water in Wuxi, China. Acanthamoeba could be a public health threat to the contact lens wearers and, therefore, its prevalence should be monitored.