Case Of Granulomatous Amoebic Encephalitis Research Articles

A Case of Granulomatous Amoebic Encephalitis diagnosed and intervened at an Early Stage

A Case of Granulomatous Amoebic Encephalitis diagnosed and intervened at an Early Stage

Occurrence and genetic evaluation of potentially pathogenic Acanthamoeba genotypes in nasal mucosa of immunocompromised patients: a case-control study in Iran.

The occurrence of granulomatous amoebic encephalitis (GAE) was investigated due to the exposure of a large number of immunocompromised patients to opportunistic Acanthamoeba infections, which in most cases are fatal. In this case-control study, 160 samples from the nasal mucosa of immunocompromised patients were collected between February 2019 to February 2020 in Isfahan, central Iran, using sterile cotton swabs; 150 ethnically matched controls were included. The pathogenic potential of the identified isolates was evaluated using temperature and osmotolerance assays. The identification of Acanthamoeba infection was confirmed by both morphological and phylomolecular tools. Of 310 collected samples, 32 strains, including 25 (15.6%) and 7 (4.6%) isolates, were positive for the Acanthamoeba genus in the patient and control groups, respectively. The topology of the phylogenetic tree indicated that all the Acanthamoeba strains belonged to the T4 genotype. Only five of the isolates genotyped as T4 were positive for potential pathogenic assays. The heterogeneity analysis of 18S ribosomal RNA sequences of Acanthamoeba in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) and hepatitis B and C patients revealed significant genetic diversity (haplotype diversity [Hd] 0.511) compared with that of healthy individuals (Hd 0.210). The circulation of pathogenic isolates of Acanthamoeba, particularly in HIV/AIDS patients, along with their genetic traits, indicates that clinicians should be more aware of fatal cases of GAE, especially in suspected encephalitis, in Iran and worldwide.

Gold-Conjugated Curcumin as a Novel Therapeutic Agent against Brain-Eating Amoebae.

Balamuthia mandrillaris and Naegleria fowleri are free-living amoebae that cause infection of the central nervous system, granulomatous amoebic encephalitis (GAE) and primary amoebic meningoencephalitis (PAM), respectively. The fact that mortality rates for cases of GAE and PAM are more than 95% indicates the need for new therapeutic agents against those amoebae. Considering that curcumin exhibits a wide range of biological properties and has shown efficacy against Acanthamoeba castellanii, we evaluated the amoebicidal properties of curcumin against N. fowleri and B. mandrillaris. Curcumin showed significant amoebicidal activities with an AC50 of 172 and 74 μM against B. mandrillaris and N. fowleri, respectively. Moreover, these compounds were also conjugated with gold nanoparticles to further increase their amoebicidal activities. After conjugation with gold nanoparticles, amoebicidal activities of the drugs were increased by up to 56 and 37% against B. mandrillaris and N. fowleri, respectively. These findings are remarkable and suggest that clinically available curcumin and our gold-conjugated curcumin nanoparticles hold promise in the improved treatment of fatal infections caused by brain-eating amoebae and should serve as a model in the rationale development of therapeutic interventions against other infections.

A case report of granulomatous amoebic encephalitis by Group 1 Acanthamoeba genotype T18 diagnosed by the combination of morphological examination and genetic analysis

BackgroundThe diagnosis of granulomatous amoebic encephalitis is challenging for clinicians because it is a rare and lethal disease. Previous reports have indicated that Acanthamoeba with some specific genotypes tend to cause the majority of human infections. We report a case of granulomatous amoebic encephalitis caused by Acanthamoeba spp. with genotype T18 in an immunodeficient patient in Japan after allogenic bone marrow transplantation, along with the morphological characteristics and genetic analysis.Case presentationA 52-year old man, who had undergone allogenic bone marrow transplantation, suffered from rapid-growing brain masses in addition to pneumonia and died within 1 month from the onset of the symptoms including fever, headache and disorientation. Infection with Acanthamoeba in the brain and lung was confirmed by histological evaluation; immunohistochemical staining and polymerase chain reaction analysis using autopsy samples also indicated the growth of Acanthamoeba in the brain. Gene sequence analysis indicated that this is the second documented case of infection with Acanthamoeba spp. with genotype T18 in a human host. Postmortem retrospective evaluation of cerebrospinal fluid sample in our case, as well as literature review, indicated that some cases of granulomatous amoebic encephalitis caused by Acanthamoeba may be diagnosable by cerebrospinal fluid examination.ConclusionThis case indicates that Acanthamoeba spp. with genotype T18 can also be an important opportunistic pathogen. For pathologists as well as physicians, increased awareness of granulomatous amoebic encephalitis is important for improving the poor prognosis along with the attempt to early diagnosis with cerebrospinal fluid.

Experimental infection of T4 Acanthamoeba genotype determines the pathogenic potential.

T4 is the Acanthamoeba genotype most related to cases of granulomatous amoebic encephalitis (GAE) in immunocompromised patients and of keratitis in contact lens wearers. The determination of the pathogenic potential of Acanthamoeba clinical and environmental isolates using experimental models is extremely important to elucidate the capacity of free-living organisms to establish and cause disease in hosts. The aim of this study was to compare and evaluate the histopathology and culture between two different routes of experimental infection of T4 Acanthamoeba isolated from environmental and clinical source in mice (intracranial and intraperitoneal). Swiss isogenic healthy mice were inoculated with 10(4) trophozoites by intracranial (IC) and intraperitoneal (IP) routes and observed during 21days. The brains from animals inoculated by the IC route were collected and from the animals of the IP inoculation group, the brains, livers, kidneys, spleens, and lungs were removed. The organs were prepared and appropriately divided to be evaluated with histopathology and culture. There was no significant difference between the inoculation routes in terms of isolates recovery (χ(2) = 0.09; p = 0.76). In the IC group, isolate recovery rate was significantly higher in histopathology than the one achieved by culture (χ(2) = 6.45; p < 0.01). Experimental infection revealed that all isolates inoculated could be considered invasive because it was possible to recover evolutive forms of Acanthamoeba in both routes. This work represents the first in vivo pathogenicity assay of primary isolation source in Central region of Brazil showing in vivo pathogenicity and hematogenous spread capacity of these protozoa, improving the knowledge on free-living amoebae isolates.

Twenty years of acanthamoeba diagnostics in Austria.

Acanthamoebae are the causative agents of an often seriously progressing keratitis (AK) occurring predominantly in contact lens wearers and can cause several disseminating infections potentially resulting in granulomatous amoebic encephalitis (GAE) in the immunocompromised host. Our institution is the Austrian reference laboratory for Acanthamoeba diagnostics and the aim of this study was to give an overview of proven cases of Acanthamoeba infections in Austria during the past 20 yr. All samples of patients with suspected AK or GAE were screened for Acanthamoeba spp. by culture and/or PCR and the detected amoebae were genotyped. Altogether, 154 cases of AK and three cases of GAE were diagnosed. Age of the AK patients ranged from 8 to 82 yr (mean 37.8) and 58% of the patients were female. Approximately 89% of the AK patients were contact lens wearers, almost all cases were unilateral and 19% of the patients required a keratoplasty. Age of the GAE patients ranged from 2 to 25 yr (mean 14.7), all were HIV-negative, but two were severely immunosuppressed at the time of diagnosis. The predominant genotype in the AK cases was T4, other genotypes found were T3, T5, T6, T10 and T11. The three GAE cases involved genotypes T2, T4 and T5.

Unusual Presentation of Multiple Nerve Palsies with Granulomatous Encephalitis Due to Acanthamoeba Species

Acanthamoeba spp is one of the common protozoa in soil, usually found in fresh water and other habitats. We are presenting a case of Granulomatous amoebic encephalitis presented with unusual symptoms of third, fourth, sixth, and seventh nerve palsy with diplopia, ptosis, and migraine. Differential diagnosis of tuberculous (TB) meningitis was initially considered but was ruled out by CSF TB PCR. There was no history of exposure to sources such as fresh water ponds and contaminated swimming pools. CSF wet mount and culture confirmed the diagnosis of Acanthamoeba spp. Specific antiparasitic therapy was started and patient improved with successful resolution of symptoms.

Acanthamoeba meningoencephalitis in an immunocompetent patient: An autopsy case report

Chronic granulomatous CNS infections may be caused by tuberculosis, fungi and rarely by free-living amoeba, especially in immunocompromised individuals. We report a rare, fatal case of granulomatous amoebic encephalitis in an immunocompetent patient mimicking CNS tuberculosis, and review the imageological features and diagnostic tests.

Granulomatous Amoebic Encephalitis Caused by Balamuthia Mandrillaris -Case Report-

A 51-year-old immunocompetent Japanese woman presented with a rare case of granulomatous amoebic encephalitis (GAE) caused by Balamuthia mandrillaris. She was brought to our hospital with epilepsy. Magnetic resonance imaging of the brain revealed a homogeneously enhanced solitary mass in the left frontal lobe. Histological diagnosis was made by a biopsy, which suggested lymphomatoid granulomatosis. After that, her neurological condition got worse. New masses were found and had spread across the whole brain. She died 2 months later of cerebral hernia. Autopsy revealed that the patient had GAE caused by Balamuthia mandrillaris. GAE is usually fatal, and is difficult to diagnose except at autopsy. Therefore, awareness of this disease is important, and earlier diagnosis and the development of a better therapeutic strategy will improve clinical outcome.

Granulomatous Amoebic Meningoencephalitis in an Immunocompetent Patient

To report a case of granulomatous amoebic encephalitis caused by Balamuthia mandrillaris. Case report. University hospital. An adult female patient without any apparent suppressor immune system factor had central nervous system infection caused by B mandrillaris. Clinical, neuroimaging, and pathology findings. This study shows the diagnosis of B mandrillaris encephalitis suspected from a cerebral biopsy specimen and confirmed by immunohistochemical and polymerase chain reaction studies. This study demonstrates that the diagnosis of amoebic encephalitis represents a clinical challenge and confirming diagnoses are made, in most cases, after death. High suspicion, histopathologic examination, and indirect immunofluorescence, polymerase chain reaction, and cytokine studies from tissue and cerebrospinal fluid are the main devices to reach the diagnosis.

Ante mortem diagnosis of amoebic encephalitis in a haematopoietic stem cell transplanted patient

Acanthamoeba species are widely distributed free-living amoebae showing an increased role as human pathogens causing encephalitis, keratitis, pneumonitis and dermatitis. A haematopoietic stem cell transplanted (HSCT) patient developed purulent meningitis while awaiting regrafting. The meningitis was thought to be an endogenous infection arising from the mucous membranes primarily involving the cervicofacial regions, probably due to haematogenous spread facilitated by surgery. We diagnosed a fatal case of granulomatous amoebic encephalitis caused by Acanthamoeba castellanii by direct microscopy of a cerebrospinal fluid sample (CSF), Acanthamoeba cultivation, Giemsa staining, polymerase chain reaction and sequencing.

Granulomatous Amoebic Encephalitis Caused by Acanthamoeba Amoebae of Genotype T2 in a Human Immunodeficiency Virus-Negative Patient

Acanthamoeba amoebae of genotype T2 were identified as the causative agent of Acanthamoeba skin lesions and granulomatous amoebic encephalitis (GAE) in a human immunodeficiency virus-negative patient with underlying tuberculosis. To our knowledge this, is the first case of GAE involving genotype T2.