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1.
J Int Med Res ; 50(5): 3000605221093217, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35505464

RESUMO

Balamuthia mandrillaris is a free-living heterotrophic amoeba found in soil that causes a rare and usually fatal granulomatous amebic encephalitis. We report an immunocompetent patient infected with B. mandrillaris encephalitis diagnosed by next-generation sequencing (NGS). Clinical manifestations included sudden headache and epilepsy with disturbance of consciousness. The opening pressure of cerebrospinal fluid (CSF) was 220 mmH2O, with mildly elevated white blood cell numbers and elevated protein levels. Cranial magnetic resonance imaging revealed abnormal signals in the right frontal lobe, left parietal lobe, and left occipital lobe. CSF NGS detected B. mandrillaris. Albendazole and metronidazole combined with fluconazole were administered to the patient immediately, but his condition deteriorated and he eventually died. Encephalitis caused by B. mandrillaris is rare and has a high mortality rate. Clinical manifestations are complex and diverse, but early diagnosis is very important for successful treatment. This can be aided by the metagenomic NGS of CSF.


Assuntos
Amebíase , Balamuthia mandrillaris , Encefalite , Amebíase/diagnóstico , Amebíase/tratamento farmacológico , Balamuthia mandrillaris/genética , Encefalite/diagnóstico por imagem , Encefalite/tratamento farmacológico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imageamento por Ressonância Magnética , Masculino
2.
BMC Infect Dis ; 22(1): 54, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35032997

RESUMO

BACKGROUND: Granulomatous amoebic encephalitis (GAE) is a rare central nervous system infection caused by the Balamuthia mandrillaris or Acanthamoeba species. Diagnosis is challenging because of the non-specific clinical presentation, cerebrospinal fluid analysis, and radiological features. There is no effective treatment for GAE to date. CASE PRESENTATION: A 54-year-old male was admitted to hospital after experiencing acute onset of numbness and weakness on his left limb. Due to the initial consideration of intracranial tumor, surgical removal of the right parietal lesion was performed. However, the patient had a headache accompanied by diplopia, difficulty walking and a new lesion was found in the left occipital-parietal lobe two weeks after the first operation. High-throughput next-generation sequencing (NGS) detected the presence of high copy reads of the B. mandrillaris genome sequence in the patient's blood, cerebral spinal fluid (CSF), and brain tissue. Pathological investigation of the brain tissue showed granulomatous changes and amoebic trophozoite scattered around blood vessels under high magnification. The patient was re-operated due to developing progressive confusion caused by subfalcine herniation of the left cerebral hemisphere. The lesions of the right parietal lobe were obviously decreasing in size after the first surgery, and the lesions of the left occipital lobe and the sunfalcine herniation didn't ameliorate two months after the second surgery. The patient was transferred to local hospital for continuous treatment with sulfamethoxazole and azithromycin. After five months of the second surgery, the patient showed good recovery with mild headache. CONCLUSIONS: This is the first report of a patient with B. mandrillaris encephalitis initially confirmed by NGS and have experienced two excisions, responding favorably to the combination of surgeries and medications. Early surgical resection of intracranial lesions combined with drug treatment may offer the chance of a cure.


Assuntos
Amebíase , Balamuthia mandrillaris , Infecções Protozoárias do Sistema Nervoso Central , Encefalite , Encefalite Infecciosa , Amebíase/diagnóstico , Amebíase/tratamento farmacológico , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico , Infecções Protozoárias do Sistema Nervoso Central/tratamento farmacológico , Encefalite/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade
4.
Lancet Infect Dis ; 22(3): e93-e100, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34838200

RESUMO

Cutaneous infection by Balamuthia mandrillaris is a rare condition that is sometimes complicated by life-threatening CNS involvement. It often evades timely diagnosis due to its rarity and non-specific clinical manifestations. Patients can be either immunocompetent or immunocompromised. It is probably transmitted via inhalation or inoculation through broken skin, and then spreads to the brain and other organs through haematogenous spread. It is important for clinicians to be aware of this disease because rapid diagnosis and subsequent therapy has, in some cases, been associated with survival. In this Grand Round, we report the case of a 7-year-old boy who presented with large, chronic plaques on his face. Several biopsies showed non-specific granulomatous inflammation. The patient deteriorated rapidly and died within 1 month of displaying abnormal symptoms in the CNS. Immunohistochemical staining of skin tissue identified B mandrillaris as the infectious agent. The diagnosis was confirmed with PCR, which detected B mandrillaris DNA in formalin-fixed skin tissue sections. B mandrillaris infection should be considered in the differential diagnosis of patients with chronic granulomatous lesions. We also reviewed the epidemiology, B mandrillaris in nature and in the laboratory, clinical manifestations, histopathology, diagnosis, and treatment of infection.


Assuntos
Amebíase , Balamuthia mandrillaris , Amebíase/diagnóstico , Amebíase/tratamento farmacológico , Amebíase/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Criança , Face/patologia , Granuloma , Humanos , Masculino
5.
Pediatr Infect Dis J ; 41(2): e54-e57, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34862343

RESUMO

Cerebral amebic encephalitis due to Balamuthia mandrillaris is a rare yet typically fatal disease. As such, identification of the clinical characteristics, appropriate diagnostic workup and commencement of treatment is frequently delayed. Here, we present a case of a 4-year-old male with a B. mandrillaris cerebral abscess successfully treated with expedited neurosurgical resection and broad-spectrum antimicrobial therapy.


Assuntos
Amebíase , Balamuthia mandrillaris , Abscesso Encefálico , Infecções Protozoárias do Sistema Nervoso Central , Amebíase/diagnóstico por imagem , Amebíase/tratamento farmacológico , Amebíase/cirurgia , Anti-Infecciosos/uso terapêutico , Encéfalo/diagnóstico por imagem , Encéfalo/parasitologia , Encéfalo/patologia , Abscesso Encefálico/diagnóstico por imagem , Abscesso Encefálico/tratamento farmacológico , Abscesso Encefálico/cirurgia , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico por imagem , Infecções Protozoárias do Sistema Nervoso Central/tratamento farmacológico , Infecções Protozoárias do Sistema Nervoso Central/cirurgia , Pré-Escolar , Humanos , Masculino
6.
Trends Parasitol ; 38(3): 230-245, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34758928

RESUMO

Naegleria fowleri, Balamuthia mandrillaris, and Acanthamoeba spp. can cause devastating brain infections in humans which almost always result in death. The symptoms of the three infections overlap, but brain inflammation and the course of the disease differ, depending on the amoeba that is responsible. Understanding the differences between these amoebae can result in the development of strategies to prevent and treat these infections. Recently, numerous scientific advancements have been made in the understanding of pathogenicity mechanisms in general, and the basic biology, epidemiology, and the human immune response towards these amoebae in particular. In this review, we combine this knowledge and aim to identify which factors can explain the differences between the lethal brain infections caused by N. fowleri, B. mandrillaris, and Acanthamoeba spp.


Assuntos
Acanthamoeba , Amebíase , Amoeba , Balamuthia mandrillaris , Encefalite , Naegleria fowleri , Acanthamoeba/fisiologia , Amebíase/diagnóstico , Amebíase/epidemiologia , Encefalite/diagnóstico , Humanos , Naegleria fowleri/fisiologia
7.
J Clin Microbiol ; 60(1): e0022821, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-34133896

RESUMO

Infections caused by Naegleria fowleri, Acanthamoeba spp., and Balamuthia mandrillaris result in a variety of clinical manifestations in humans. These amoebae are found in water and soil worldwide. Acanthamoeba spp. and B. mandrillaris cause granulomatous amoebic encephalitis (GAE), which usually presents as a mass, while N. fowleri causes primary amoebic meningoencephalitis (PAM). Acanthamoeba spp. can also cause keratitis, and both Acanthamoeba spp. and B. mandrillaris can cause lesions in skin and respiratory mucosa. These amoebae can be difficult to diagnose clinically as these infections are rare and, if not suspected, can be misdiagnosed with other more common diseases. Microscopy continues to be the key first step in diagnosis, but the amoeba can be confused with macrophages or other infectious agents if an expert in infectious disease pathology or clinical microbiology is not consulted. Although molecular methods can be helpful in establishing the diagnosis, these are only available in referral centers. Treatment requires combination of antibiotics and antifungals and, even with prompt diagnosis and treatment, the mortality for neurological disease is extremely high.


Assuntos
Acanthamoeba , Amebíase , Amoeba , Balamuthia mandrillaris , Naegleria fowleri , Amebíase/diagnóstico , Humanos
8.
Ann Lab Med ; 42(2): 196-202, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635613

RESUMO

BACKGROUND: Identifying the causal pathogen of encephalitis remains a clinical challenge. A 50-year-old man without a history of neurological disease was referred to our department for the evaluation of an intracranial lesion observed on brain magnetic resonance imaging (MRI) scans, and the pathology results suggested protozoal infection. We identified the species responsible for encephalitis using thymine-adenine (TA) cloning, suitable for routine clinical practice. METHODS: We extracted DNA from a paraffin-embedded brain biopsy sample and performed TA cloning using two universal eukaryotic primers targeting the V4-5 and V9 regions of the 18S rRNA gene. The recombinant plasmids were extracted, and the inserted amplicons were identified by Sanger sequencing and a homology search of sequences in the National Center for Biotechnology Information Basic Local Alignment Search Tool. RESULTS: The infection was confirmed to be caused by the free-living amoeba Balamuthia mandrillaris. Two of 41 colonies recombinant with 18S V4-5 primers and 35 of 63 colonies recombinant with the 18S V9 primer contained B. mandrillaris genes; all other colonies contained human genes. Pathogen-specific PCR ruled out Entamoeba histolytica, Naegleria fowleri, Acanthamoeba spp., and Toxoplasma gondii infections. CONCLUSIONS: This is the first report of B. mandrillaris-induced encephalitis in Korea based on molecular identification. TA cloning with the 18S rRNA gene is a feasible and affordable diagnostic tool for the detection of infectious agents of unknown etiology.


Assuntos
Balamuthia mandrillaris , Encefalite , Adenina , Balamuthia mandrillaris/genética , Clonagem Molecular , Encefalite/diagnóstico , Eucariotos , Humanos , Masculino , Pessoa de Meia-Idade , Timina
9.
Infect Genet Evol ; 97: 105190, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34954104

RESUMO

We reported a case of B.mandrillaris amoebic encephalitis in mainland China. Metagenomics next-generation sequencing helped initial diagnosis and then polymerase chain reaction of the B.mandrillaris in the infected nasal skin tissues reported positive and amoeba cysts were found in the tissue under microscopic observation.


Assuntos
Amebíase/parasitologia , Balamuthia mandrillaris/isolamento & purificação , Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Encefalite Infecciosa/parasitologia , Adolescente , China , Evolução Fatal , Humanos , Masculino
10.
Front Med ; 15(6): 842-866, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34825341

RESUMO

Among various genera of free-living amoebae prevalent in nature, some members are identified as causative agents of human encephalitis, in which Naegleria fowleri followed by Acanthamoeba spp. and Balamuthia mandrillaris have been successively discovered. As the three dominant genera responsible for infections, Acanthamoeba and Balamuthia work as opportunistic pathogens of granulomatous amoebic encephalitis in immunocompetent and immunocompromised individuals, whereas Naegleria induces primary amoebic meningoencephalitis mostly in healthy children and young adults as a more violent and deadly disease. Due to the lack of typical symptoms and laboratory findings, all these amoebic encephalitic diseases are difficult to diagnose. Considering that subsequent therapies are also affected, all these brain infections cause significant mortality worldwide, with more than 90% of the cases being fatal. Along with global warming and population explosion, expanding areas of human and amoebae activity in some regions lead to increased contact, resulting in more serious infections and drawing increased public attention. In this review, we summarize the present information of these pathogenic free-living amoebae, including their phylogeny, classification, biology, and ecology. The mechanisms of pathogenesis, immunology, pathophysiology, clinical manifestations, epidemiology, diagnosis, and therapies are also discussed.


Assuntos
Amebíase , Balamuthia mandrillaris , Infecções Protozoárias do Sistema Nervoso Central , Naegleria fowleri , Amebíase/diagnóstico , Amebíase/epidemiologia , Encéfalo , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico , Infecções Protozoárias do Sistema Nervoso Central/epidemiologia , Criança , Humanos
11.
Sci Rep ; 11(1): 21664, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34737367

RESUMO

Balamuthia mandrillaris, a pathogenic free-living amoeba, causes cutaneous skin lesions as well as granulomatous amoebic encephalitis, a 'brain-eating' disease. As with the other known pathogenic free-living amoebas (Naegleria fowleri and Acanthamoeba species), drug discovery efforts to combat Balamuthia infections of the central nervous system are sparse; few targets have been validated or characterized at the molecular level, and little is known about the biochemical pathways necessary for parasite survival. Current treatments of encephalitis due to B. mandrillaris lack efficacy, leading to case fatality rates above 90%. Using our recently published methodology to discover potential drugs against pathogenic amoebas, we screened a collection of 85 compounds with known antiparasitic activity and identified 59 compounds that impacted the growth of Balamuthia trophozoites at concentrations below 220 µM. Since there is no fully annotated genome or proteome of B. mandrillaris, we sequenced and assembled its transcriptome from a high-throughput RNA-sequencing (RNA-Seq) experiment and located the coding sequences of the genes potentially targeted by the growth inhibitors from our compound screens. We determined the sequence of 17 of these target genes and obtained expression clones for 15 that we validated by direct sequencing. These will be used in the future in combination with the identified hits in structure guided drug discovery campaigns to develop new approaches for the treatment of Balamuthia infections.


Assuntos
Balamuthia mandrillaris/genética , Desenho de Fármacos/métodos , Trofozoítos/genética , Acanthamoeba/genética , Amebíase/tratamento farmacológico , Amoeba/genética , Balamuthia mandrillaris/efeitos dos fármacos , Balamuthia mandrillaris/crescimento & desenvolvimento , Sequência de Bases , Encéfalo/patologia , Descoberta de Drogas/métodos , Encefalite/patologia , Expressão Gênica/genética , Naegleria fowleri/genética , Transcriptoma/genética , Trofozoítos/efeitos dos fármacos
12.
BMC Neurol ; 21(1): 392, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627183

RESUMO

BACKGROUND: Granulomatous amoebic encephalitis (GAE) is an infrequent and fatal infectious disease worldwide. Antemortem diagnosis in this condition is very difficult because clinical manifestations and neuroimaging are nonspecific. CASE PRESENTATION: A 60-year-old Japanese woman was admitted with a chief complaint of left homonymous hemianopsia. Brain-MRI showed extensive necrotizing lesions enhanced by gadolinium, in the right frontal lobe, right occipital lobe, and left parietal lobe. Epithelioid granulomas of unknown etiology were found in the biopsied brain specimens. Shotgun metagenomic sequencing using a next-generation sequencer detected DNA fragments of Balamuthia mandrillaris in the tissue specimens. The diagnosis of granulomatous amoebic encephalitis was confirmed using an amoeba-specific polymerase chain reaction and immunostaining on the biopsied tissues. CONCLUSIONS: Shotgun metagenomics is useful for the diagnosis of central nervous system infections such as GAE wherein the pathogens are difficult to identify.


Assuntos
Amebíase , Balamuthia mandrillaris , Encefalite , Amebíase/diagnóstico , Balamuthia mandrillaris/genética , Encefalite/diagnóstico , Feminino , Granuloma/diagnóstico , Humanos , Metagenômica , Pessoa de Meia-Idade
13.
Yonsei Med J ; 62(6): 563-567, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34027644

RESUMO

Central nervous system infections caused by free-living amoeba are very rare, but often fatal. The typical image findings of amebic meningoencephalitis are non-specific, showing ring-like enhancement. We report the first case of fulminant disseminating fatal granulomatous amebic encephalitis caused by Balamuthia mandrillaris in an immunocompetent patient in South Korea. Our case exhibited two interesting features: one was the unusual clinical course and the other was additional image findings. Magnetic resonance imaging revealed a rim-enhancing lesion with intralesional blooming dark signal intensity on susceptibility weighted imaging and low signal intensity on diffusion weighted images and on apparent diffusion coefficient maps. Differential diagnosis was started from a tumor or non-tumorous lesion, and diagnosis was difficult due to the rarity of the disease. Following the clinical and diagnostic courses of our case, we recommend inspecting image findings of granulomatous amebic encephalitis for early diagnosis.


Assuntos
Amebíase , Amoeba , Balamuthia mandrillaris , Encefalite , Amebíase/diagnóstico por imagem , Encéfalo , Encefalite/diagnóstico por imagem , Humanos , República da Coreia
14.
Parasite ; 28: 36, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33843581

RESUMO

In this review, we focus on the sequenced genomes of the pathogens Naegleria fowleri, Acanthamoeba spp. and Balamuthia mandrillaris, and the remarkable discoveries regarding the pathogenicity and genetic information of these organisms, using techniques related to the various omics branches like genomics, transcriptomics, and proteomics. Currently, novel data produced through comparative genomics analyses and both differential gene and protein expression in these free-living amoebas have allowed for breakthroughs to identify genes unique to N. fowleri, genes with active transcriptional activity, and their differential expression in conditions of modified virulence. Furthermore, orthologous genes of the various nuclear genomes within the Naegleria and Acanthamoeba genera have been clustered. The proteome of B. mandrillaris has been reconstructed through transcriptome data, and its mitochondrial genome structure has been thoroughly described with a unique characteristic that has come to light: a type I intron with the capacity of interrupting genes through its self-splicing ribozymes activity. With the integration of data derived from the diverse omic sciences, there is a potential approximation that reflects the molecular complexity required for the identification of virulence factors, as well as crucial information regarding the comprehension of the molecular mechanisms with which these interact. Altogether, these breakthroughs could contribute to radical advances in both the fields of therapy design and medical diagnosis in the foreseeable future.


TITLE: Application des sciences de l'omique à l'étude de Naegleria fowleri, Acanthamoeba spp. et Balamuthia mandrillaris : état actuel et projections futures. ABSTRACT: Dans cette revue, l'accent est mis sur les génomes séquencés des agents pathogènes Naegleria fowleri, Acanthamoeba spp. et Balamuthia mandrillaris, et les découvertes remarquables concernant la pathogénicité et l'information génétique de ces organismes, en utilisant des techniques liées aux diverses branches de l'omique comme la génomique, la transcriptomique et la protéomique. Actuellement, de nouvelles données produites par des analyses génomiques comparatives et l'expression différentielle des gènes et des protéines dans ces amibes libres ont permis des percées pour identifier des gènes uniques à N. fowleri, des gènes avec une activité transcriptionnelle active et leur expression différentielle dans des conditions de virulence modifiée. En outre, les gènes orthologues des divers génomes nucléaires des genres Naegleria et Acanthamoeba ont été regroupés. Le protéome de B. mandrillaris a été reconstruit grâce aux données du transcriptome, et la structure de son génome mitochondrial décrite de manière détaillée, mettant ainsi une caractéristique unique à jour : un intron de type I avec la capacité d'interrompre les gènes par son activité d'auto-épissage des ribozymes. Avec l'intégration des données issues des diverses sciences omiques, il existe une approximation potentielle qui reflète la complexité moléculaire requise pour l'identification des facteurs de virulence, ainsi que des informations cruciales concernant la compréhension des mécanismes moléculaires avec lesquels ceux-ci interagissent. Dans l'ensemble, ces percées pourraient contribuer à des progrès notables à la fois dans les domaines de la conception de la thérapie et du diagnostic médical dans un avenir proche.


Assuntos
Acanthamoeba , Balamuthia mandrillaris , Naegleria fowleri , Acanthamoeba/genética , Balamuthia mandrillaris/genética , Genoma de Protozoário , Genômica , Naegleria fowleri/genética , Proteômica , Transcriptoma , Virulência
15.
Diagn Microbiol Infect Dis ; 100(4): 115180, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33887622

RESUMO

Balamuthia mandrillaris encephalitis is a rare disease with high mortality in the children. Due to the lack of specificity in clinical manifestations, laboratory tests, and neuroimaging, the diagnosis of the disease is difficult, especially the diagnosis of etiology. Currently, the evidence shows that the diagnosis of the disease depends on local brain biopsy or autopsy, and it is difficult to detect the pathogens by traditional etiological detection methods in blood and cerebrospinal fluid. We report a 9-year-old Chinese girl with B. mandrillaris encephalitis who was diagnosed with metagenomic next-generation sequencing (mNGS). The technology of mNGS can provide rapid, early etiological diagnosis without the need for a local brain biopsy, which can buy time for the early treatment of patients. We also provide a comprehensive literature review on this disease.


Assuntos
Amebíase/diagnóstico por imagem , Balamuthia mandrillaris/genética , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico por imagem , Encefalite/diagnóstico por imagem , Metagenômica/métodos , Amebíase/parasitologia , Balamuthia mandrillaris/patogenicidade , Encéfalo/diagnóstico por imagem , Encéfalo/parasitologia , Criança , Encefalite/parasitologia , Evolução Fatal , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imageamento por Ressonância Magnética
16.
J Zoo Wildl Med ; 52(1): 310-314, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33827191

RESUMO

Granulomatous amoebic encephalitis caused by the free-living amoeba Balamuthia mandrillaris is a highly fatal disease that was first isolated from a mandrill (Mandrillus sphinx), and has since been diagnosed in several nonhuman primates including orangutans. Indirect immunofluorescence antibody (IFA) techniques for Balamuthia have been used in the fields of human medicine and epidemiology both for exposure assessment and screening of clinical patients for antemortem diagnosis. Stored serum samples from five captive Northwest Bornean orangutans (Pongo pygmaeus pygmaeus), including one who had died from B. mandrillaris infection, housed at a single facility were screened with a human IFA assay for B. mandrillaris. Only the single, clinically affected individual was seropositive, and the results suggest that the use of the available human B. mandrillaris IFA assay is a novel diagnostic option for detection of Balamuthia antibodies in this species. A validated screening serological test could be used in individuals exhibiting signs consistent with granulomatous amoebic encephalitis to facilitate earlier antemortem diagnosis of Balamuthia infection, which is critical if treatment is to be pursued. This pilot study presents the use of serological detection methods for B. mandrillaris screening in a nonhuman primate. Subsequent use of the B. mandrillaris IFA assay in the larger captive population should be pursued for validation of the test and to provide further information on seroprevalence and evaluation of risk factors for exposure to Balamuthia and subsequent development of disease.


Assuntos
Amebíase/veterinária , Doenças dos Símios Antropoides/diagnóstico , Balamuthia mandrillaris , Técnica Indireta de Fluorescência para Anticorpo/métodos , Pongo pygmaeus/parasitologia , Amebíase/diagnóstico , Animais , Animais de Zoológico , Doenças dos Símios Antropoides/parasitologia , Feminino , Humanos
17.
Am J Trop Med Hyg ; 104(5): 1836-1840, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33720845

RESUMO

It is about half a century since free-living amoebae were recognized as pathogenic organisms, but there is still much we should learn about these rare fatal human infectious agents. A recently introduced causative agent of granulomatous amoebic encephalitis, Balamuthia mandrillaris, has been reported in a limited number of countries around the world. A 3-year-old girl was referred to our tertiary hospital because of inability to establish a proper diagnosis. She had been experiencing neurologic complaints including ataxia, altered level of consciousness, dizziness, seizure, and left-sided hemiparesis. The patient's history, physical examination results, and laboratory investigations had led to a wide differential diagnosis. Computed tomography (CT) scan and magnetic resonance imaging analyses revealed multiple mass lesions. As a result, the patient underwent an intraoperative frozen section biopsy of the brain lesion. The frozen section study showed numerous cells with amoeba-like appearances in the background of mixed inflammatory cells. Medications for free-living amoebic meningoencephalitis were administered. PCR assay demonstrated B. mandrillaris as the pathogenic amoeba. Unfortunately, the patient died 14 days after her admission. To our knowledge, this is the first report of B. mandrillaris meningoencephalitis in the Middle East and the first time we have captured the organism during a frozen-section study.


Assuntos
Amebíase/parasitologia , Ataxia/parasitologia , Balamuthia mandrillaris/patogenicidade , Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Tontura/parasitologia , Paresia/parasitologia , Convulsões/parasitologia , Amebíase/diagnóstico por imagem , Amebíase/patologia , Ataxia/diagnóstico por imagem , Ataxia/patologia , Balamuthia mandrillaris/crescimento & desenvolvimento , Biópsia , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico por imagem , Infecções Protozoárias do Sistema Nervoso Central/patologia , Pré-Escolar , Tontura/diagnóstico por imagem , Tontura/patologia , Evolução Fatal , Feminino , Humanos , Irã (Geográfico) , Imageamento por Ressonância Magnética , Paresia/diagnóstico por imagem , Paresia/patologia , Convulsões/diagnóstico por imagem , Convulsões/patologia , Tomografia Computadorizada por Raios X
18.
Rev Argent Microbiol ; 53(2): 129-134, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33012571

RESUMO

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.


Assuntos
Amebíase , Balamuthia mandrillaris , Adulto , Amebíase/diagnóstico , Evolução Fatal , Granuloma , Humanos , Peru , Adulto Jovem
19.
Primates ; 62(1): 51-61, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32920664

RESUMO

A female Bornean orangutan (Pongo pygmaeus) aged 11 years and 6 months was examined by veterinarians after caretakers observed lethargy and facial grimacing. Within 72 h the primate had left-sided hemiparesis that worsened over the next week. An MRI revealed a focal right-sided cerebral mass suspected to be a neoplasm. Ten days after onset of clinical signs, the orangutan died. On postmortem exam, the medial right parietal lobe was replaced by a 7 × 4 × 3.5 cm focus of neuromalacia and hemorrhage that displaced the lateral ventricle and abutted the corpus callosum. Histopathology of the cerebral lesion revealed pyogranulomatous meningoencephalitis with intralesional amoeba trophozoites and rare cysts. Fresh parietal lobe was submitted to the Centers for Disease Control and Prevention lab for multiplex free-living amoebae real-time PCR and detected Balamuthia mandrillaris DNA at a high burden. Mitochondrial DNA was sequenced, and a 760-bp locus 19443F/20251R was compared to several human infections of B. mandrillaris and shown to be identical to the isolates from four human cases of encephalitis: 1998 in Australia, 1999 in California, 2000 in New York, and 2010 in Arizona. Indirect immunofluorescent antibody testing of stored serum samples indicated exposure to B. mandrillaris for at least 2 years prior to death. Within 1 week of the orangutan's death, water from the exhibit was analyzed and identified the presence of B. mandrillaris DNA, elucidating a possible source of exposure. B. mandrillaris, first reported in a mandrill in 1986, has since occurred in humans and animals and is now considered an important emerging pathogen.


Assuntos
Balamuthia mandrillaris/isolamento & purificação , Infecções Protozoárias do Sistema Nervoso Central/veterinária , Meningoencefalite/veterinária , Pongo pygmaeus , Doenças dos Primatas/parasitologia , Animais , Arizona , Balamuthia mandrillaris/genética , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico , DNA Mitocondrial/isolamento & purificação , DNA de Protozoário/isolamento & purificação , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Meningoencefalite/diagnóstico , Meningoencefalite/parasitologia , Doenças dos Primatas/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Água/parasitologia
20.
Front Immunol ; 12: 768065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069540

RESUMO

Balamuthia mandrillaris is one cause of a rare and severe brain infection called granulomatous amoebic encephalitis (GAE), which has a mortality rate of >90%. Diagnosis of Balamuthia GAE is difficult because symptoms are non-specific. Here, we report a case of Balamuthia amoebic encephalomyelitis (encephalitis and myelitis) in a woman with breast cancer. She sustained trauma near a garbage dump 2 years ago and subsequently developed a skin lesion with a Mycobacterium abscessus infection. She experienced dizziness, lethargy, nausea and vomiting, inability to walk, and deterioration of consciousness. Next-generation sequencing of cerebrospinal fluid (CSF) samples revealed B. mandrillaris, and MRI of both brain and spinal cord showed abnormal signals. T-cell receptor (TCR) sequencing of the CSF identified the Top1 TCR. A combination of amphotericin B, flucytosine, fluconazole, sulfamethoxazole, trimethoprim, clarithromycin, pentamidine, and miltefosine was administrated, but she deteriorated gradually and died on day 27 post-admission.


Assuntos
Amebíase , Neoplasias da Mama , Encefalomielite , Adulto , Amebíase/tratamento farmacológico , Amebíase/genética , Amebíase/imunologia , Balamuthia mandrillaris/genética , Balamuthia mandrillaris/imunologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/parasitologia , Encefalomielite/tratamento farmacológico , Encefalomielite/genética , Encefalomielite/imunologia , Encefalomielite/parasitologia , Evolução Fatal , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imageamento por Ressonância Magnética
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