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Primary Amoebic Meningoencephalitis in an Infant due to Naegleria fowleri
Vinay Khanna,Ruchee Khanna,Shrikiran Hebbar,V. Shashidhar,Sunil Mundkar,Frenil Munim,Karthick Annamalai,Deepak Nayak,Chiranjay Mukhopadhayay
Case Reports in Neurological Medicine , 2011, DOI: 10.1155/2011/782539
Abstract: Primary amoebic meningoencephalitis (PAM) caused by free-living amebae Naegleria fowleri is a rare and fatal condition. A fatal case of primary amoebic meningoencephalitis was diagnosed in a 5-month-old infant who presented with the history of decrease breast feeding, fever, vomiting, and abnormal body movements. Trophozoites of Naegleria fowleri were detected in the direct microscopic examination of CSF and infant was put on amphotericin B and ceftazidime. Patient condition deteriorated, and he was discharged against medical advice and subsequently expired. We also reviewed previously reported 8 Indian cases of primary amoebic meningoencephalitis (PAM) and observed that for the last 5 years, none of the patients responded to amphotericin B. Has an era of amphotericin B-resistant Naegleria fowleri been emerged? Management strategy of PAM needs to be reviewed further.
Primary amoebic meningoencephalitis due to Naegleria fowleri  [PDF]
A Angrup,L Chandel,A Sood,K Thakur,SC Jaryal
Journal of Institute of Medicine , 2010, DOI: 10.3126/joim.v32i2.4949
Abstract: The genus Naegleria comprises of free living ameboflagellates found in soil and fresh water. More than 30 species have been isolated but only N. fowleri has been associated with human disease. N. fowleri causes primary amoebic meningoencephalitis (PAM), an acute, often fulminant infection of CNS. Here we report a rare and first case of PAM in an immunocompetent elderly patient from this part of the country. Amoeboid and flagellate forms of N. fowleri were detected in the direct microscopic examination of CSF and confirmed by flagellation test in distilled water, demonstrating plaques /clear areas on 1.5% non nutrient agar and its survival at 42°C.
Primary Amoebic Meningoencephalitis Caused by Naegleria fowleri: An Old Enemy Presenting New Challenges  [PDF]
Ruqaiyyah Siddiqui,Naveed Ahmed Khan
PLOS Neglected Tropical Diseases , 2014, DOI: 10.1371/journal.pntd.0003017
Abstract: First discovered in 1899, Naegleria fowleri is a protist pathogen, known to infect the central nervous system and produce primary amoebic meningoencephalitis. The most distressing aspect is that the fatality rate has remained more than 95%, despite our advances in antimicrobial chemotherapy and supportive care. Although rare worldwide, most cases have been reported in the United States, Australia, and Europe (France). A large number of cases in developing countries go unnoticed. In particular, religious, recreational, and cultural practices such as ritual ablution and/or purifications, Ayurveda, and the use of neti pots for nasal irrigation can contribute to this devastating infection. With increasing water scarcity and public reliance on water storage, here we debate the need for increased awareness of primary amoebic meningoencephalitis and the associated risk factors, particularly in developing countries.
Meningoencephalitis by Naegleria fowleri: epidemiological study in Anzoategui state, Venezuela
Cerme?o, Julman R.;Hernández, Isabel;El Yasin, Helal;Tinedo, Rubén;Sánchez, Raúl;Pérez, Gladys;Gravano, Rosalía;Ruiz, Aida;
Revista da Sociedade Brasileira de Medicina Tropical , 2006, DOI: 10.1590/S0037-86822006000300007
Abstract: a case of primary amoebic meningoencephalitis produced by naegleria fowleri was diagnosed in the independencia county of anzoategui state, venezuela. this case motivated the realization of the present epidemiological study with the aim of identifying free-living amoebae in this area. representative water samples were taken and physicochemical and microbiologic analyses were carried out. trophozoites and cysts of naegleria spp, were detected in 44.4% (n=4). an excellent concordance was found among the observations of free-living amoebae in smears and those of monoxenic cultures in non nourishing agar with klebsiella pneumoniae (kappa=1; p= 0.003). a variable load of aerobic mesophils was obtained. moulds and yeast averages presented 3.0 cfu/ml (sd± 2.0) and 102.9 cfu/ml (sd± 32.2), respectively. one hundred per cent of the samples presented a most probable number of total and fecal coliforms of 240,000 nmp/100ml. naegleria spp was present in waters of the independence county of anzoategui state, which constitutes a risk for people that use these sources.
ITS and pB2.5 gene expression of Naegleria fowleri in drug resistance  [PDF]
Jundee Rabablert, Supathra Tiewcharoen, Virach Junnu
Health (Health) , 2011, DOI: 10.4236/health.2011.38088
Abstract: Naegleria fowleri was causative agent of primary amoebic meningoencephalitis (PAM). Accroding to the failure of treatment, several researches reported the activity of chemotherapeutic drugs against N.fowleri but we did not know the drug resistance of the amoebae. The purpose of this study was to examine the effects of drugs (amphotericin B, artesunate, azithromycin, voriconazole, chlorpromazine, fluconazole and gentamicin sulphate) on ITS and pB2.3 genes of Naegleria fowleri trophozoites. Our study demonstrated gene expression of treated N.fowleri by RT-PCR. The results reviewed that ITS gene of N. fowleri showed up regulate to amphotericin B, azithromicin and gentamicin sulphate, while pB2.3 gene showed up regulate to artesunate. These results compared with beta actin (house keeping gene) expression at time intervals 15 - 120 min. The change of gene expression of treated N.fowleri was possibly to cause of drug resistance. The mechanism of drug resistance genes ITS and pB2.3 of N.fowleri should be clarified in further study.
Primary Amoebic Meningoencephalitis in an Iranian Infant
Zahra Movahedi,Mohammad Reza Shokrollahi,Mohammad Aghaali,Hosein Heydari
Case Reports in Medicine , 2012, DOI: 10.1155/2012/782854
Abstract: Introduction. Naegleria fowleri, a free living amoeba, can cause devastating and deadly diseases in humans. This is the first report of primary amoebic meningoencephalitis from Iran. Case report. A five-month-old male infant presented with the history of fever and eye gaze for three days, after beginning of bacterial meningitis, a plain and contrast CT revealed communicated hydrocephalus. In the repeat of CSF analysis on microscopic examination of wet preparation of CSF, Naegleria Fowleri was seen. Then, Amphotericin B and Rifampin were started. On followup, two months later, the patient was totally asymptomatic. Conclusion. Though occurrence of PAM is rare, this unusual disease has grave prognosis, so infection with free living amoebas must be considered in differential diagnosis of pediatric patients of purulent meningitis without evidence of bacteria on Gram’s stain and imaging findings, nonspecific brain edema on CT or hydrocephalus even without history of contact.
Survey of Naegleria fowleri in Geothermal Recreational Waters of Guadeloupe (French West Indies)  [PDF]
Mirna Moussa, Johan F. De Jonckheere, Jér?me Guerlotté, Vincent Richard, Alexandra Bastaraud, Marc Romana, Antoine Talarmin
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0054414
Abstract: In 2008 a fatal case of primary amoebic meningoencephalitis, due to the amoeboflagellate Naegleria fowleri, occurred in Guadeloupe, French West Indies, after a child swam in a bath fed with geothermal water. In order to improve the knowledge on free-living amoebae in this tropical part of France, we investigated on a monthly basis, the presence of Naegleria spp. in the recreational baths, and stream waters which feed them. A total of 73 water samples, 48 sediments and 54 swabs samples were collected from 6 sampling points between June 2011 and July 2012. The water samples were filtered and the filters transferred to non-nutrient agar plates seeded with a heat-killed suspension of Escherichia coli while sediment and swab samples were placed directly on these plates. The plates were incubated at 44°C for the selective isolation of thermophilic Naegleria. To identify the Naegleria isolates the internal transcribed spacers, including the 5.8S rDNA, were amplified by polymerase chain reaction and the sequence of the PCR products was determined. Thermophilic amoebae were present at nearly all collection sites. The pathogenic N. fowleri was the most frequently encountered thermophilic species followed by N. lovaniensis. The concentration of N. fowleri was rather low in most water samples, ranging from 0 to 22 per liter. Sequencing revealed that all N. fowleri isolates belonged to a common Euro-American genotype, the same as detected in the human case in Guadeloupe. These investigations need to be continued in order to counsel the health authorities about prevention measures, because these recreational thermal baths are used daily by local people and tourists.
Demostración del ameboflagelado Naegleria fowleri como agente etiológico de meningoencefalitis amébica primaria en Santiago de Cuba Demonstration of flagellum ameba Naegleria fowleri as etiological agent of primary amebic meningoencephalitis in Santiago de Cuba
Lillian Sierra Calzado
Revista Cubana de Investigaciones Biom??dicas , 2011,
Abstract: En los últimos a os se ha demostrado que el amebo-flagelado Naegleria fowleri es el causante de la meningoencefalitis amébica primaria (MEAP). En Cuba ha sido mencionada la sospecha de su presencia en un líquido céfalo-raquídeo (LCR) de una ameba cuya locomoción y circunstancias sugería que pudiera ser esta ameba. Se realizó el análisis en fresco y en cultivo, con Test de Flagelación de 64 muestras de LCR seleccionadas al azar a partir de las 173 que presentaron las características de transparencia y negatividad a bacterias, requisitos iniciales en búsqueda de este agente, partiendo de una muestra inicial de 1 488 muestras de LCR procedentes de pacientes con meningoencefalitis clínicamente establecidas. De estos 64 LCR, 2 resultaron positivos a la evaluación por los diferentes métodos lo que permitió te irlos con Giemsa, demostrar su capacidad de flagelación y su resistencia a TMT. Las características citoquímicas de los líquidos concordaban con lo planteado en la literatura y uno de los pacientes sobrevivió, el otro falleció. La patogenicidad de los ameboflagelados aislados de esas dos muestras de LCR se comprobó en el modelo animal ratón albino suizo y fueron observados al microscopio electrónico. Lo anterior confirma microbiológicamente por primera vez en el país este agente etiológico, aunque ya había elementos clínicos y de laboratorio de sospecha en casos anteriores. During the last years it has been demonstrated that the flagellae-carring ameba Naegleria fowleri is the aethiologic agent of the primary amoebic meningoencephalitis (PAME), in Cuba the suspicion of its presence has been mentioned in a Cefalo Raquideal Fluid (CRF) of an ameba whose locomotion and circumstances suggested that it could be this organism. The present work carries out the analysis in fresh CRF samples and after culture, performing the Flagelation Test of the 64 CRF that presented the characteristics of transparency and negativity to bacterial culture ,needed to suspicion of this flagellae-carring ameba, leaving of an starting sample of 1488 CRF.From this analysed sample of CRF only two were positive to the observation of amebas what allowed to tint them with Giemsa and also with Lugol, to demonstrate their flagelation capacity and their resistance to TMT in the corresponding test. The citochemical characteristics of the liquids agreed with that outlined in the literature for this organisms,and one of the patients survived, the other one died. The patogenicity of the isolated flagellae-carring amebas was proven in the animal model of Swiss albino mouse and both isolated str
Improved Method for the Detection and Quantification of Naegleria fowleri in Water and Sediment Using Immunomagnetic Separation and Real-Time PCR  [PDF]
Bonnie J. Mull,Jothikumar Narayanan,Vincent R. Hill
Journal of Parasitology Research , 2013, DOI: 10.1155/2013/608367
Abstract: Primary amebic meningoencephalitis (PAM) is a rare and typically fatal infection caused by the thermophilic free-living ameba, Naegleria fowleri. In 2010, the first confirmed case of PAM acquired in Minnesota highlighted the need for improved detection and quantification methods in order to study the changing ecology of N. fowleri and to evaluate potential risk factors for increased exposure. An immunomagnetic separation (IMS) procedure and real-time PCR TaqMan assay were developed to recover and quantify N. fowleri in water and sediment samples. When one liter of lake water was seeded with N. fowleri strain CDC:V212, the method had an average recovery of 46% and detection limit of 14 amebas per liter of water. The method was then applied to sediment and water samples with unknown N. fowleri concentrations, resulting in positive direct detections by real-time PCR in 3 out of 16 samples and confirmation of N. fowleri culture in 6 of 16 samples. This study has resulted in a new method for detection and quantification of N. fowleri in water and sediment that should be a useful tool to facilitate studies of the physical, chemical, and biological factors associated with the presence and dynamics of N. fowleri in environmental systems. 1. Introduction Naegleria fowleri, a thermophilic free-living ameba found in freshwater environments, causes primary amoebic meningoencephalitis (PAM), a rare and typically fatal disease in children and young adults [1, 2]. In the USA, N. fowleri is commonly detected in warm freshwater environments such as lakes, rivers, inadequately disinfected swimming pools, geothermal waters (e.g., hot springs), thermally impacted surface water (e.g., from power plants), and water distribution systems [3–15]. While N. fowleri is generally considered to be widespread in the environment, especially in warm weather geographic areas, environmental factors are likely associated with the distribution of PAM in the USA. In recent years there has been an increase in the geographical distribution of PAM cases in the USA and in 2010, the first confirmed case of PAM was identified in Minnesota, the northernmost USA state in which this infection has been documented [9, 16]. These developments highlight the need for improved environmental detection and quantification methods in order to study the ecology of N. fowleri and to evaluate potential risk factors for increased exposure to this ameba. The most probable number (MPN) method is reliant on culture methods developed in the 1970s [17] and consists of spreading Escherichia coli over agar plates and
Activity of chlorpromazine on nfa1 and Mp2CL5 genes of Naegleria fowleri trophozoites  [PDF]
Supathra Tiewcharoen, Jundee Rabablert, Prucksawan Chetannachan, Dusit Worawirunwong, Virach Junnu, Noppamas Pungsub
Health (Health) , 2011, DOI: 10.4236/health.2011.33032
Abstract: Amoeba treatment of patients suffering from pri-mary amoebic meningoencephalitis caused by Naegleria fowleri has not been successful. Dam-aged morphology and effect on genes of N. fowleri as the result of its initial interaction with drug may provide clue to the success of treatment. In this study, we investigated the activity of chlorpromazine compared with amphotericin B and voriconazole against N.fowleri Khon Kaen strain using cell based assay and molecular techniques. Scanning electron and light micro-graph showed the drug interaction of treated amoebae with 0.098 ug/ml chlorpromazine was faster than 0.002 ug/ml amphotericin B and 12.5 ug/ml of voriconazole. The morphological cha-racteristics of treated amoebae with Gomori’s trichrome stain correlated to the scanning elec-tron microscope study. The effect of drugs to nfa1 and Mp2CL5 genes of treated amoebae found that at 120 min post exposure, chlorpromazine, voriconazole inhibited both genes except amphotericin B. Most of drug inhibited nfa1 except fluconazole. The results evaluated that chlorpromazine was higher potency and rapidly activity than amphotericin B and voriconazole against N. fowleri trophozoites.
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