Identificación de amebas de vida libre en tanques de almacenamiento de agua de edificios del área metropolitana de Ambato / Identification of free-living amoebas in water storage tanks of buildings in the metropolitan area of Ambato

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)

A history of over 40 years of potentially pathogenic free-living amoeba studies in Brazil - a systematic review

Free-living amoeba (FLA) group includes the potentially pathogenic genera Acanthamoeba, Naegleria, Balamuthia, Sappinia, and Vermamoeba, causative agents of human infections (encephalitis, keratitis, and disseminated diseases). In Brazil, the first report on pathogenic FLA was published in the 70s and showed meningoencephalitis caused by Naegleria spp. FLA studies are emerging, but no literature review is available to investigate this trend in Brazil critically. Thus, the present work aims to integrate and discuss these data. Scopus, PubMed, and Web of Science were searched, retrieving studies from 1974 to 2020. The screening process resulted in 178 papers, which were clustered into core and auxiliary classes and sorted into five categories: wet-bench studies, dry-bench studies, clinical reports, environmental identifications, and literature reviews. The papers dating from the last ten years account for 75% (134/178) of the total publications, indicating the FLA topic has gained Brazilian interest. Moreover, 81% (144/178) address Acanthamoeba-related matter, revealing this genus as the most prevalent in all categories. Brazil's Southeast, South, and Midwest geographic regions accounted for 96% (171/178) of the publications studied in the present work. To the best of our knowledge, this review is the pioneer in summarising the FLA research history in Brazil.

Encefalitis por ameba de vida libre: reporte de caso / Free-living amoeba encephalitis: case report

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

Primer informe clínico de Balamuthia mandrillaris en el distrito de Camaná, Arequipa, Perú / First case report of the Balamuthia mandrillaris in the Camaná district of Arequipa, Peru

Resumen Las infecciones por amebas de vida libre causan compromiso cutáneo y neurológico. Estas afecciones presentan una baja frecuencia pero una alta letalidad, mayor al 98%. Gene ralmente el cuadro clínico es inespecífico y los exámenes de laboratorio no son de gran ayuda, por lo que representa un reto diagnóstico y terapéutico. En este informe presentamos el caso de un paciente de 21 años que fue hospitalizado por un síndrome convulsivo con tumoraciones cerebrales, además de una lesión cutánea en el muslo derecho. El análisis histopatológico, PCR y el cuadro clínico permitieron el diagnóstico de encefalitis amebiana granulomatosa. A pesar del tratamiento, el paciente tuvo un desenlace fatal.

Abstract Infections by free-living amoebas cause cutaneous and neurological compromise. These conditions have a low frequency, but a high lethality more than 98%. Generally, the clinical picture is nonspecific; the laboratory tests dont help, so it represents a diagnostic and therapeutic challenge. In this report, we present the case of a 21-year-old patient, who was hospitalized for a convulsive syndrome with brain tumors, in addition to a cutaneous lesion on the right thigh. Histopathological analysis, PCR and the clinical picture allowed the diagnosis of granulomatous amebic encephalitis. Despite the treatment, the patient had a fatal outcome.

Occurrence of The Pathogenic Amoeba Naegleria fowleri, Pathogenesis, Diagnosis, and Treatment Options

@#Naegleria fowleri is the causative agent of primary amoebic meningoencephalitis (PAM) that infects the central nervous system (CNS). The amoeba is present ubiquitously. The infection is rare but has a high mortality rate. The pathogenic amoeba reaches the host through the nasal passage and migrates along the olfactory nerves to reach the human brain and cause severe destruction of the CNS. As Malaysia has a large population that practising ablutions in daily routine, the risk of infection increases. Two mechanisms associated with the infection include contact-dependent and contact-independent. Signs and symptoms vary from early stage to later stage of infection. CSF and brain biopsy are the common specimens collected used to diagnose the PAM infection and usually detect and identify by PCR method. As for treatment, the CDC of United States America has recommended the usage of miltefosine that provides promising in vitro therapy against N. fowleri. This review will discuss more on the occurrence of N. fowleri, pathogenicity, diagnostic tools, and pharmacotherapy approach against N. fowleri infection.

Potentially pathogenic Acanthamoeba genotype T4 isolated from dental units and emergency combination showers

BACKGROUND Acanthamoeba is the genus of free-living amoebae that is most frequently isolated in nature. To date, 20 Acanthamoeba genotypes have been described. Genotype T4 is responsible for approximately 90% of encephalitis and keratitis cases. Due to the ubiquitous presence of amoebae, isolation from environmental sources is not uncommon; to determine the clinical importance of an isolation, it is necessary to have evidence of the pathogenic potential of amoebae. OBJECTIVE The aim of this study was to physiologically characterise 8 Acanthamoeba T4 isolates obtained from dental units and emergency combination showers and to determine their pathogenic potential by employing different laboratory techniques. METHODS Eight axenic cultures of Acanthamoeba genotype T4 were used in pathogenic potential assays. Osmotolerance, thermotolerance, determination and characterisation of extracellular proteases and evaluation of cytopathic effects in MDCK cells were performed. FINDINGS All of the isolates were osmotolerant, thermotolerant and had serine proteases from 44-122 kDa. Two isolates had cytopathic effects on the MDCK cell monolayer. MAIN CONCLUSION The presence of Acanthamoeba T4 with pathogenic potential in areas such as those tested in this study reaffirms the need for adequate cleaning and maintenance protocols to reduce the possibility of infection with free-living amoebae.

Balamuthia mandrillaris en el Perú, lesiones cutáneas, meningoencefalitis y métodos de cultivo / Balamuthia mandrillaris in Perú, skin lesions, meningoencephalitis and cultivation methods

Las amebas de vida libre son microorganismos abundantes en el suelo y agua en todo el planeta. Algunas especies de estas amebas son capaces de causar muerte en el ser humano y animales, asi como Naegleria fowleri (N. fowleri), Acanthamoeba sp. T4 principalmente y Balamuthia mandrillaris (B. mandrillaris). El 98% de los casos reportados en el mundo han fallecido. En Peru alrededor de 8 casos de meningoencefalitis por Acanthamoeba sp. se han reportado y mas de 55 casos por B. mandrillaris . Ningun caso por N. fowleri ha sido documentado oficialmente en el Peru. B. mandrillaris es de dificil diagnostico y aislamiento en medios de cultivo. En esta revision pretendo documentar la historia de casos reportados de los ultimos 40 años y describir los medios de cultivo utiles para su crecimiento. La identificacion morfologica y molecular de Balamuthia es critica en el diagnostico de meningoencefalitis amebiana.

Free-living amoebae are abundant microorganisms in soil and water worldwide. Some species of these amoebae are capable of causing death in humans and animals, such as Naegleria fowleri (N. fowleri) , Acanthamoeba sp . T4 , and Balamuthia mandrillaris (B. mandrillaris) . Some 98% of cases reported in the world have resulted in death. In Peru, 8 cases of meningoencephalitis due to Acanthamoeba sp. have been reported and more than 55 cases per B. mandrillaris . No case of N. fowleri has been officially documented in Peru. B. mandrillaris is difficult to diagnose and isolate in culture media. In this review we document the history of reported cases of the last 40 years and describe useful methods for their growth. Morphological and molecular identification of Balamuthia is critical to the diagnosis of amoebic meningoencephalitis.

Acanthamoeba spp. en piscinas cubiertas de la ciudad de Bahía Blanca, provincia de Buenos Aires, Argentina / Acanthamoeba spp. in indoor swimming pools in Bahía Blanca city, Buenos Aires province, Argentina

Acanthamoeba ha sido aislada de numerosos hábitats incluyendo piletas de natación. Estudiar su distribución es importante ya que algunas especies causan enfermedad en el hombre. El objetivo del presente trabajo fue la búsqueda, aislamiento y caracterización de protozoos del género Acanthamoeba en piscinas cubiertas de la ciudad de Bahía Blanca, Argentina, en las cuatro estaciones del año durante 2007-2008. Se estudiaron 7 piscinas y en cada una se tomaron cuatro muestras: fondo, superficie, raspado de pared y para análisis bacteriológico. Las muestras se analizaron por observación directa y por cultivo en agar no nutritivo a 37 °C y a 42 °C. La identificación genérica se realizó de acuerdo con las características morfológicas de quistes y trofozoítos y para identificar Naegleria se realizó la prueba de transformación ameboflagelar. En 5 de las 7 piscinas se aislaron amebas de vida libre al menos en una época del año. La prueba de transformación ameboflagelar resultó negativa, descartando al género Naegleria. Todos los aislamientos correspondieron al género Acanthamoeba Grupos II y III de Pussard y Pons. Si bien la eliminación de Acanthamoeba en las aguas de natatorios resulta muy difícil por tratarse de un protozoario ubicuo y sumamente resistente a los desinfectantes comúnmente utilizados, se recomienda una limpieza profunda de las piscinas que minimice los riesgos de infección.

Acanthamoeba spp. has been isolated from many habitats, including swimming pools. Investigations on its distribution are relevant because many of its species cause human diseases. The aim of the present work was to investigate, isolate and characterize protozoan of the genus Acanthamoeba from indoor swimming pools in Bahía Blanca, Argentina, in the four seasons, during the 2007-2008 period. Seven pools were studied and samples were collected from the bottom, surface and wall by scraping them. Besides, samples for bacteriological analysis were taken from each pool. The samples were analyzed by direct observation and by culturing on non nutritive agar at 37 °C and at 42 °C. The generic identification was performed according to the morphologic characteristics of cysts and trofozoites, while the amoebo-flagellate transformation test was carried out to identify Naegleria. Free-living amoebas were isolated from five of the seven swimming pools examinated, in at least one season. Naegleria genus was not found as the amoebo-flagellate transformation tests were negative in all samples. All the isolations corresponded to the genus Acanthamoeba belonging to Pussard & Pons morphological Groups II and III. Although elimination of Acanthamoeba from the water is difficult because it is a ubiquitous protozoan. which is highly resistant to the commonly used disinfectants, a thorough cleaning of the pools to minimize the risks of infection is recommended.

The role of domestic tap water in Acanthamoeba contamination in contact lens storage cases in Korea

A survey was carried out from August to December 2004 in Pusan, Korea to document the presence of free-living amoeba (FLA), including the genus Acanthamoeba, in both contact lens storage cases and domestic tap water. Acanthamoeba was isolated from 5 (4.2%) in 120 contact lens storage cases. Four house tap water samples from residents, whose contact lens storage cases had been contaminated by Acanthamoeba, were also found to be contaminated with Acanthamoeba. Therefore, the contamination rate of FLA and Acanthamoeba in domestic tap water was investigated in order to examine the role of domestic tap water in Acanthamoeba contamination of contact lens storage cases. FLA and Acanthamoeba were identified in 97 (46.8%) and 16 (7.7%) of the 207 domestic tap water samples, respectively. There were no significant differences between the contamination rates of FLA in tap water according to the filtration plant of origin. No FLA was detected in the tap water directly supplied by the water purification plants. Water storage tanks appear to promote FLA colonization, including Acanthamoeba, in domestic tap water. This increases the risk of Acanthamoeba contamination in contact lens storage cases as well as increasing the risk of Acanthamoeba keratitis.

Acanthamoeba Keratitis: Microscopic and Ultrastructural Findings: A case report

Acanthamoeba keratitis is uncommon and rarely reported in Korea. It has been reported in world literature as a very severe, progressive necrotizing stromal keratitis due to a non-parasitic free-living amoeba. It is frequently associated with minimal corneal trauma especially from contact lens but sometimes occurs in patients without any past history. We report a case of acanthamoeba keratitis without a specific past history in a 42-year-old man. Light and electron microscopy demonstrated severe stromal keratitis with numerous thick-walled cysts, 10~15 m in diameter, scattered in the superficial and deep stroma. Because this keratitis is most often mistaken for fungal, bacterial or herpetic keratitis, early confirmatory diagnosis by direct smear, biopsy or culture is essentially required for the prevention of visual loss or devastating eyeball loss.