Members of the genus Acanthamoeba are usually free-living amebae and are found in a variety of ecological niches including soil, fresh and brackish water, dust in air, filters of heating, ventilating, and air conditioning units, swimming pools and hot tubs, etc. Occasionally, they are also known to cause central nervous system infections in humans and other animals. We isolated into culture an ...

Acanthamoeba keratitis (AK) is a sight-threating infection of the cornea that mostly affects contact lens wearers. Until now, AK treatment remains very difficult due to the existence of a highly resistant cyst stage in the life cycle of Acanthamoeba which is extremely resistant to most of the available anti-amoebic compounds. Moreover, current treatment of AK is usually based in the combination...

Several species of free-living amoebae can cause encephalomyelitis in animals and humans. Disseminated acanthamoebiasis was diagnosed in pyogranulomatous lesions in brain, thyroid, pancreas, heart, lymph nodes, and kidney of a one-year-old dog. Acanthamoeba sp. was identified in canine tissues by conventional histology, by immunofluorescence, by cultivation of the parasite from the brain of the...

Pathogenic free-living amoebae are common in nature, but few clinical infections by these amoebae have been reported. This has prompted studies of host susceptibility factors in humans. A survey of normal human sera from three New Zealand Health Districts was made; antibodies to pathogenic free-living amoebae were found in all sera, with titers ranging from 1:5 to 1:20 for Naegleria spp. and fr...

Free-living amoebae (FLA) belonging to Acanthamoeba and Sappinia genera as well as Balamuthia mandrillaris and Naegleria fowleri species are aerobic, mitochondriate, eukaryotic protists that occur worldwide and can potentially cause infections in humans and other animals (Visvesvara and Maguire, 2006; Visvesvara et al., 2007). Due to the fact that these amoebae have the ability to exist as free...

Acanthamoeba keratitis is a rare but serious corneal disease, often observed in contact lens wearers. Clinical treatment of infected patients frequently involves the use of polyhexamethylene biguanide (PHMB), a polymer used as a disinfectant and antiseptic, which is toxic also for the epithelial cells of the cornea. Prompt and effective diagnostic tools are hence highly desiderable for both sta...

Rokitamycin is a new macrolide containing 16 carbon atoms, strongly inhibitory for Acanthamoeba castellanii, an opportunistic protozoa of humans which cause primarily amoebic keratitis and chronic, but fatal, amoebic granulomatous meningoencephalitis. Chitosan microspheres were prepared as carriers to obtain a controlled release of rokitamycin, able to improve the antiamoebic activity of this d...

Acanthamoeba spp. are the causative agents of Acanthamoeba keratitis (AK), which mainly occurs in contact lens wearers, and of skin lesions, granulomatous amoebic encephalitis (GAE), and disseminating diseases in the immunocompromised host. AK therapy is complex and irritating for the eye, skin lesions are difficult to treat, and there is no effective treatment for GAE. Therefore, new anti-Acan...

Previous molecular examination of Acanthamoeba spp. has resulted in the determination of distinct genotypes in this genus (designated T1-T12, T14). Genotype T4 has been responsible for the majority of cases of Acanthamoeba keratitis. Here we examine the relative abundance of environmental T4 isolates on beaches and ask whether they have temperature and salinity tolerances that could enhance pat...

AIMS Sensitive diagnosis of Acanthamoeba infections may prevent the clinical condition from becoming worse. In order to improve the diagnosis tool performances, we studied the implication of the DNA extraction procedures on the detection of Acanthamoeba by real-time PCR. METHODS Acanthamoeba cysts mixed with a tag virus were processed according to different DNA preparation procedures: heat, P...