neglecia fowleri akanthomiba and balmuthya those three are pathogenic free-living amoeba so the first one negleriofoleri which is a brain eating amoeba which belongs to genus negleria that causes primary amoebic meningoencephalitis p a pam now coming on to its history and distribution it was named after malcolm faller along with carter it is thermophilic that is it is a heat-loving organism that thrives in warm water at low oxygen tension and it is also seen in soil in last 10 years from 2002 to 2010 about 32 infections were reported in us and in india a total of 17 cases have been reported now coming on to its morphology there are two morphological forms the first one is the trophozoite and the second one is the cyst the trophozoite form is again divided into two amiibo trophozoite form and flagellate trophozoite form so here you can see three pictures of this morphological forms the first one is amoeboid form the second one the flagellate form and the third one cis form it's a stage so the amoeboid form you can see here some of the structures named as lobopodia nucleus cariosome food vacuole contractile vacuole and all and on the uh in the second picture you can see two flagella and then the last one there is a thick smooth double lead cis wall so about the amoeboid form it is a feeding growing and replicating form having a diameter of about 10 to 20 micrometer it is having a spherical nucleus big endosome and pulsating vacuoles and there is another structure called as amiibo storms these are vacuoles that appears to be densely granular and it is used for engulfing rbcs and wbcs and there is another structure called as lobopodia you can see here so this one is meant for active motility the second form is the flagellate for so you can see the picture it is having two flagellae so it is biflagelate and this form that is the flagellate form occurs when trophozoites are transferred to distilled water and this occurs within a minute and it is also known as amoebo flagellate because this flagellate form can be reverted to amoeboid foam that is it is interchangeable so hence the name amiibo flagellate and the next one is the cyst stage or this assist form it is a resistant form that offers protection from desiccation for deprivation and odd so you can see it is a spherical urn structure having a diameter of about 7 to 10 micrometer and it can withstand moderate heat about 45 degree celsius but it dies at chlorine levels of 2 ppm and salinity of 0.7 percentage and this cis form is not seen in clinical specimens and now this is the life cycle so you can see the three forms right cis trophozoite and flagellate form so this enders uh the human body uh during swimming diving and all so once it enters it penetrates this amoeba actually penetrates the nasal mucosa and through olfactory nerve it reaches the brain and it causes pa or primary amoebic meningoencephalitis so you can see this cyst trophozoite and flagellate forms are formed within the external environment and there is no need of any host for the in order to complete its life cycle so no need of hosts or no host is required and it is completed in the external environment and the amoeboid form of tropozoid multiplies by binary fission and during unfavorable condition it forms cyst and the flagellate form of trophozoid helps in spread of this informal area to new water bodies and coming on to pathogenesis the incubation period is about two days to two weeks and the man acquires infection by swimming or diving in warm water contaminated with infor lady and the amoeba invade nasal mucosa pass through the olfactory nerve invade the cribriform plate endures the meninges and rain and it initiates acute purulent meningitis and encephalitis called pan now coming on to its clinical manifestations there will be fever which is abrupt in onset and you know it is a brain eating amoeba so there will be frondal headache vomiting stick stiff neck ataxia zisa and coma now lab diagnosis the specimen used are csf and biops brain tissue now coming on to its microscopy in wet mount it detects trophozoites with active directional motility at autopsy trophozoites can be demonstrated in brain histologically by eye of staining and culture is done on non-nutrient agar plates coated with e coli and liquid accentic media and both trophozoites and cis occurs in in culture in molecular methods pcr is preferred uh and in case of treatment the drug of choice is amphotericin b which is given intravenously instilled directly into the brain and treatment combining uh myconazole and sulphur diazine has shown limited success only when administered early now coming on to the next organism that is acanthomiba there are four species akindomiba kalbazoni acanthomiba cassilani acanthomiba polyphagia economics it causes three kinds of diseases the first one is gaa granulomatous amoebic encephalitis the second one is the infections of lung and skin the third one chronic amoebic keratitis so ah first about its morphology so uh here is a picture that shows the two morphological forms same as that of the neglediopholary but here both the trophozoites and the cis i infectious so about the trophozoite it is about uh 20 to 50 micrometer in size and uh just like uh neglect there is another pseudopodia here and it is called as akandopodia which is a spine like pseudopodia and unlike negleriofolary there is no flagellate stage and now about the cyst which varies in shape and it is a double wall cyst having an ectocyst and an endocyst coming on to the life cycle you can see uh as you know both the cyst and the trophozoites are infectious and these can endorse uh the human body through various ways it can be either through the eyes or through the nasal passage or through ulcerated or broken skin and all so the transmission is by inhalation of cysts and trophozoites or by injection of the cyst or even through traumatized skin or eyes once it enters it can cause several infections like it can cause keratitis of the eyes gae and on so next is the pathogenesis here the manicures infection by inhalation of the aerosols or dust containing cysts and trophozoites and it invades the lungs and through the bloodstream it reaches the cns and multiplied by binary fission and it causes granulomatous amoebic encephalitis so in case of nagleria folary it was through the olfactory nerve it reaches the cns over the brain but in case of acanthomoeba it is through the bloodstream it reaches the cns and causes gae now coming on to the risk factors the risk factors includes immunodeficiency diabetes malignancies sle alcoholism and it is fatal within days now coming on to the clinical manifestation it can cause keratitis encephalitis so this is a picture that shows the akanto amoeba keratitis and uh look it is actually seen in the healthy individuals those who use contact lens and it's it is a severely painful condition and it resembles that of the severe hepatic keratitis and there will be unilateral photophobia excessive tearing redness and foreign body sensation and this keratitis and evidence can leads to permanent visual impairment or blindness now gae or grandla matters amoebic encephalitis this is actually seen in immunocompromised patients but the keratitis you know it is seen in healthy individuals but ga is uh commonly seen in immunocompromised patients and the clinical picture is uh similar to that of intracranial space occupying lesions with seizures perisis and mental deterioration and another disease or another infection uh includes disseminated infections which is also seen in immunocompromised patients that affects the skin lungs and sinus now coming on to its lab diagnosis the specimens uh used includes corneal scraping as it causes keratitis and csf uh because it causes gae and brain biopsy in gae then about amoeba keratitis demonstration of cysteine corneal scrapings are performed by means of wet mount histology and culture and now uh growth is also detected in neutrin agar overlaid with live or dead e coli and incubated at 30 degree celsius for rapid diagnosis fluorescent microscopy using calculus white staining and ifa test is performed in case of gae demonstration of trophozoites and cysts in brain biopsy culture and if microscopy using monoclonal antibodies are performed and the csf shows lymphocytic pleuocytosis slightly elevated protein levels and normal or slightly decreased uh glucose level and ct scan and now about the treatment for kento amoeba keratitis since it is an infection that affects the eyes uh topical administration of bygone chlorhexidine with or without diameter agent is preferred in case of severe in severe cases keratoplasty is uh and in gaa in case of gae there is no effective treatment uh multi drug combinations include including pentamidine sulfadiazine refurbishing and fluconazole are being used with limited success the last organism is balmouthium androlitis that causes gae uh and these are the pictures two pictures that shows its morphological forms the first one is the cis stage and second one is the amoeboid tropozoic stage and just like uh acanthomoeba there is no flagellate stage but in the cis form it is spherical having a diameter of about six to twenty micrometer uh unlike a kendo amoeba it is having a three layered cis wall and ectosis mesosis and endocyst and uh in light microscopy you can see outer irregular wall and in a smooth wall and its transmission is through respiratory tract skin lesions the life cycle is similar to that of that kento amoeba and clinical manifestation include gaa which is seen in both healthy individuals and immunocompromised hosts that includes children and elderly individuals and coming on to the lab diagnosis uh specimen uses csf and it detects trophozoites of belmuthia mandrillaris in the csf and trophozoids and cysts in brain tissues and for molecular diagnosis pcr so by this we come to an end of this discussion on the topics negleria foleri akinto meeba and ben muthya thank you.
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