RESUMO
Infections caused by free-living amoebae pose a significant public health threat owing to growing populations of immunocompromised hosts combined with diagnostic delays, treatment difficulties, and high case fatality rates. Nasopharyngeal infections caused by Acanthamoeba are rare and the optimal treatment is not well established. We report a case of Acanthamoeba rhinosinusitis in a patient with chronic lymphocytic leukemia who presented with headaches and chronic rhinosinusitis refractory to multiple courses of antibiotics. A diagnosis of Acanthamoeba rhinosinusitis was established through broad-range polymerase chain reaction testing on sinus tissue. The patient had a favorable response to treatment, which included surgical debridement, cessation of immunosuppressants, and a three-drug regimen consisting of miltefosine, fluconazole, and sulfadiazine.
Assuntos
Acanthamoeba , Amebíase , Leucemia Linfocítica Crônica de Células B , Rinite , Sinusite , Humanos , Leucemia Linfocítica Crônica de Células B/complicações , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Sinusite/tratamento farmacológico , Sinusite/parasitologia , Sinusite/diagnóstico , Acanthamoeba/isolamento & purificação , Acanthamoeba/genética , Rinite/tratamento farmacológico , Rinite/diagnóstico , Rinite/parasitologia , Amebíase/tratamento farmacológico , Amebíase/diagnóstico , Masculino , Hospedeiro Imunocomprometido , Pessoa de Meia-Idade , Fluconazol/uso terapêutico , Idoso , Antiprotozoários/uso terapêutico , Rinossinusite , Fosforilcolina/análogos & derivadosRESUMO
Granulomatous amoebic encephalitis due to Acanthamoeba spp is a rare, near-fatal central nervous system infection. It is often seen in immunocompromised individuals. Here we describe a survivor of this infection who was co-infected with multidrug-resistant tuberculosis. He presented to us with features of meningitis and a history of chronic cough. The chest X-ray was classical for pulmonary tuberculosis. Neuroimaging was suggestive of encephalitis; herpes simplex virus PCR was negative. Cerebrospinal fluid (CSF) showed lymphocytic pleocytosis. Wet mounts revealed trophozoites of Acanthamoeba Currently, he is being treated with oral bedaquiline, levofloxacin, linezolid, clofazimine, cycloserine and pyridoxine for tuberculosis. He received intravenous amikacin and oral cotrimoxazole and fluconazole for Acanthamoeba infection for 1 month. The resolution was confirmed by repeating the CSF wet mount, culture and neuroimaging. He was then discharged with oral rifampicin, cotrimoxazole and fluconazole. He is currently under our close follow-up.
Assuntos
Acanthamoeba , Amebíase , Tuberculose Meníngea , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Masculino , Acanthamoeba/isolamento & purificação , Tuberculose Meníngea/tratamento farmacológico , Tuberculose Meníngea/complicações , Tuberculose Meníngea/diagnóstico , Amebíase/tratamento farmacológico , Amebíase/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/complicações , Imunocompetência , Coinfecção/tratamento farmacológicoRESUMO
Pathogenic and free-living Acanthamoeba are widely distributed in the environment and have been reported to cause keratitis and universally fatal encephalitis. Primary cutaneous acanthamoebiasis caused by Acanthamoeba is exceedingly rare and presents as isolated necrotic cutaneous lesions without involvement of the cornea or central nervous system. Cutaneous acanthamoebiasis often occurs in immunocompromised patients and is likely overlooked or even misdiagnosed only by cutaneous biopsy tissue histopathological analysis. Here, we report a HIV-infected 63-year-old female with oral leukoplakia for 4 months and scattered large skin ulcers all over the body for 2 months. The cause of the cutaneous lesions was unclear through cutaneous specimens histopathological analysis, and subsequently Acanthamoeba were detected by metagenomic next-generation sequencing (mNGS), which may be the cause of cutaneous lesions. Based on the mNGS results, a pathologist subsequently reviewed the previous pathological slides and found trophozoites of Acanthamoeba so that the cause was identified, and the skin ulcers improved significantly after treatment with multi-drug combination therapy. Acanthamoeba is also a host of pathogenic microorganisms. The presence of endosymbionts enhances the pathogenicity of Acanthamoeba, and no other pathogens were reported in this case. mNGS is helpful for rapidly diagnosing the etiology of rare skin diseases and can indicate the presence or absence of commensal microorganisms.
Assuntos
Acanthamoeba , Amebíase , Infecções por HIV , Sequenciamento de Nucleotídeos em Larga Escala , Metagenômica , Humanos , Feminino , Amebíase/diagnóstico , Amebíase/parasitologia , Amebíase/tratamento farmacológico , Metagenômica/métodos , Pessoa de Meia-Idade , Acanthamoeba/genética , Acanthamoeba/isolamento & purificação , Infecções por HIV/complicações , Pele/patologia , Pele/parasitologia , Resultado do TratamentoRESUMO
Acanthamoeba keratitis (AK) is a rare but potentially sight-threatening complication of corneal collagen crosslinking (CXL) for keratoconus. In this report, we describe an early adolescent male who underwent routine CXL for progressive keratoconus in his left eye. Preprocedural left visual acuity (VA) was 6/9. At day 5 postprocedure, multifocal corneal infiltrates were identified. Corneal scrape, bandage contact lens cultures and herpetic and Acanthamoeba PCR were negative. In vivo, confocal microscopy (IVCM) identified Acanthamoeba cysts within the corneal stroma. Intensive amoebicidal therapy was initiated, but recovery was complicated by significant inflammation, resulting in widespread aggressive corneal vascularisation necessitating topical steroids and steroid-sparing agents. At 10 months, his left VA was 6/24. This report emphasises the importance of maintaining a high index of suspicion for AK in cases of post-CXL microbial keratitis and highlights the diagnostic value of IVCM, particularly in culture-negative and PCR-negative cases.
Assuntos
Ceratite por Acanthamoeba , Ceratocone , Microscopia Confocal , Ceratite por Acanthamoeba/diagnóstico , Ceratite por Acanthamoeba/tratamento farmacológico , Humanos , Masculino , Ceratocone/tratamento farmacológico , Ceratocone/diagnóstico , Adolescente , Riboflavina/uso terapêutico , Colágeno , Fármacos Fotossensibilizantes/uso terapêutico , Reagentes de Ligações Cruzadas/uso terapêutico , Acuidade Visual , Córnea/parasitologia , Córnea/patologia , Acanthamoeba/isolamento & purificação , Substância Própria/patologia , Substância Própria/parasitologiaRESUMO
BACKGROUND: The genus Acanthamoeba is reported from various environmental sources and can cause multiple complications, including chronic amoebic aeratitis and amoebic granulomatous encephalitis. This study investigated the presence and genotyping of Acanthamoeba in the soil of parks and patients with malignancies referred to health centers in Zanjan city, Iran. METHODS: In this cross-sectional study, 200 soil samples were collected from amusement parks in Zanjan city from September 2017 to May 2018. Samples were cultured on 1.5% non-nutrient agar, and the Acanthamoeba genus was identified using the morphological method. PCR was performed on all positive environmental samples, and six microscopically positive clinical samples belonged to our previous study. DNA sequencing of 18S rRNA was performed to analyze the genetic pattern of some PCR-positive isolates. RESULTS: Microscopic results showed that 96 (48%) soil samples were positive. PCR confirmed all positive cases of clinical samples and 84 soil samples. Out of the PCR-positive samples, 20 soil samples and five clinical samples were sequenced successfully. All soil isolates belonged to the T4 genotype, and three and two clinical samples belonged to T4 and T5 genotypes, respectively. CONCLUSION: : The presence of Acanthamoeba in both the environment and clinical samples of Zanjan city suggests paying greater attention to the infections caused by it.
Assuntos
Acanthamoeba , Filogenia , Solo , Humanos , Acanthamoeba/genética , Acanthamoeba/isolamento & purificação , Irã (Geográfico)/epidemiologia , Estudos Transversais , Solo/parasitologia , Masculino , Amebíase/parasitologia , Amebíase/epidemiologia , Feminino , Neoplasias/genética , Neoplasias/parasitologia , Genótipo , Reação em Cadeia da Polimerase , Saúde Pública , Adulto , Pessoa de Meia-Idade , RNA Ribossômico 18S/análise , RNA Ribossômico 18S/genética , DNA de Protozoário/genética , DNA de Protozoário/análiseRESUMO
Acanthamoeba keratitis (AK) is a rare ocular disease, but it is a painful and sight-threatening infectious disease. Early diagnosis and adequate treatment are necessary to prevent serious complications. While AK is frequently diagnosis via several PCR assays or Acanthamoeba-specific antibodies, a more specific and effective diagnostic method is required. This study described the production of a polyclonal peptide antibody against the periplasmic binding protein (PBP) of A. castellanii and investigated its diagnostic potential. Western blot analysis showed that the PBP antibody specifically reacted with the cell lysates of A. castellanii. However, the PBP antibody did not interact with human corneal epithelial (HCE) cells and the other 3 major causative agents of keratitis. Immunocytochemistry (ICC) results revealed the specific detection of A. castellanii trophozoites and cysts by PBP antibodies when A. castellanii were co-cultured with HCE cells. PBP antibody specificity was further confirmed by co-culture of A. castellanii trophozoites with F. solani, S. aureus, and P. aeruginosa via ICC. The PBP antibody specifically reacted with the trophozoites and cysts of A. polyphaga, A. hatchetti, A. culbertsoni, A. royreba, and A. healyi, thus demonstrated its genus-specific nature. These results showed that the PBP polyclonal peptide antibody of A. castellanii could specifically detect several species of Acanthamoeba, contributing to the development of an effective antibody-based AK diagnostics.
Assuntos
Ceratite por Acanthamoeba , Acanthamoeba , Proteínas Periplásmicas de Ligação , Acanthamoeba/isolamento & purificação , Animais , Anticorpos , Humanos , Peptídeos , Staphylococcus aureus , TrofozoítosRESUMO
Contact lens usage has contributed to increased incidence rates of Acanthamoeba keratitis (AK), a serious corneal infection that can lead to blindness. Since symptoms associated with AK closely resemble those incurred by bacterial or fungal keratitis, developing a diagnostic method enabling rapid detection with a high degree of Acanthamoeba-specificity would be beneficial. Here, we produced a polyclonal antibody targeting the carboxylesterase (CE) superfamily protein secreted by the pathogenic Acanthamoeba and evaluated its diagnostic potential. Western blot analysis revealed that the CE antibody specifically interacts with the cell lysates and conditioned media of pathogenic Acanthamoeba, which were not observed from the cell lysates and conditioned media of human corneal epithelial (HCE) cells, Fusarium solani, Staphylococcus aureus, and Pseudomonas aeruginosa. High titers of A. castellanii-specific antibody production were confirmed sera of immunized mice via ELISA, and these antibodies were capable of detecting A. castellanii from the cell lysates and their conditioned media. The specificity of the CE antibody was further confirmed on A. castellanii trophozoites and cysts co-cultured with HCE cells, F. solani, S. aureus, and P. aeruginosa using immunocytochemistry. Additionally, the CE antibody produced in this study successfully interacted with 7 different Acanthamoeba species. Our findings demonstrate that the polyclonal CE antibody specifically detects multiple species belong to the genus Acanthamoeba, thus highlighting its potential as AK diagnostic tool.
Assuntos
Ceratite por Acanthamoeba/diagnóstico , Acanthamoeba/imunologia , Anticorpos Antiprotozoários/análise , Carboxilesterase/imunologia , Meios de Cultivo Condicionados/metabolismo , Epitélio Corneano/citologia , Acanthamoeba/classificação , Acanthamoeba/crescimento & desenvolvimento , Acanthamoeba/isolamento & purificação , Animais , Anticorpos Antiprotozoários/sangue , Especificidade de Anticorpos , Carboxilesterase/administração & dosagem , Carboxilesterase/genética , Linhagem Celular , Células Cultivadas , Lentes de Contato/parasitologia , Diagnóstico Precoce , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/parasitologia , Epitélio Corneano/metabolismo , Epitélio Corneano/parasitologia , Humanos , Imunização , Masculino , Camundongos , Proteínas de Protozoários/administração & dosagem , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologiaRESUMO
BACKGROUND: Acanthamoeba spp. are one of the free-living amoeba that spread worldwide causing keratitis. Owing to the increase in the use of lenses, whether for medical or cosmetic purposes, the incidence of disease increases every year. Contamination of the lenses with the Acanthamoeba trophozoites or cysts may lead to eye infection and cause sight-threatening keratitis in human. We isolated Acanthamoeba spp. from new lenses, used lenses, and contact lens disinfecting solutions and identified them based on morphological characteristics and molecular test. METHODS: New and used lenses and contact lens disinfecting solutions were cultured on monogenic media. Light and scanning electron microscope was used to identify Acanthamoeba spp. morphological features. Genotype identification was also evaluated using PCR sequencing of 18S rRNA gene specific primer pair JDP1 and JDP2. RESULTS: A hundred samples were examined, 29 (29%) were infected with Acanthamoeba spp. That belonged to two strains of Acanthamoeba (Acanthamoeba 41 and Acanthamoeba 68). 18S rRNA of the Acanthamoeba 41 had 99.69% sequence identity to Acanthamoeba castellanii clone HDU-JUMS-2, whereas Acanthamoeba 68 had 99.74% similar pattern to that of Acanthamoeba sp. isolate T4 clone ac2t4 that are morphologically identified as Acanthamoeba polyphaga. The obtained data revealed that the isolated strains belong to T4 genotype that was evolutionarily similar to strains isolated in Iran. CONCLUSIONS: Cosmetic lenses and disinfectant solutions are a major transmissible mode for infection. This genotype is common as the cause of Acanthamoeba keratitis. To avoid infection, care must be taken to clean the lenses and their preservative solutions and prevent contamination with the parasite.
Assuntos
Acanthamoeba/classificação , Soluções para Lentes de Contato/análise , Lentes de Contato/parasitologia , Análise de Sequência de DNA/métodos , Acanthamoeba/genética , Acanthamoeba/isolamento & purificação , Cosméticos , DNA Ribossômico/genética , Contaminação de Medicamentos , Egito , Humanos , Irã (Geográfico) , Microscopia , Microscopia Eletrônica de Varredura , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 18S/genéticaRESUMO
Acanthamoeba spp. are opportunistic human pathogens that cause granulomatous amoebic encephalitis and keratitis, and their accurate detection and enumeration in environmental samples is a challenge. In addition, information regarding the genotyping of Acanthamoeba spp. using various PCR methods is equally critical. Therefore, considering the diverse niches of habitats, it is necessary to develop an even more efficient genotyping method for Acanthamoeba spp. detection. This study improved the sensitivity of detection to avoid underestimation of Acanthamoeba spp. occurrence in aquatic environmental samples, and to accurately define the pathogenic risk by developing an efficient PCR method. In this study, a new nested genotyping method was established and compared with various PCR-based methods using in silico, lab, and empirical tests. The in silico test showed that many PCR-based methods could not successfully align specific genotypes of Acanthamoeba, except for the newly designed nested PCR and real-time PCR method. Furthermore, 52 water samples from rivers, reservoirs, and a river basin in Taiwan were analysed by six different PCR methods and compared for genotyping and detection efficiency of Acanthamoeba. The newly developed nested-PCR-based method of genotyping was found to be significantly sensitive as it could effectively detect the occurrence of Acanthamoeba spp., which was underestimated by the JDP-PCR method. Additionally, the present results are consistent with previous studies indicating that the high prevalence of Acanthamoeba in the aquatic environment of Taiwan is attributed to the commonly found T4 genotype. Ultimately, we report the development of a small volume procedure, which is a combination of recent genotyping PCR and conventional real-time PCR for enumeration of aquatic Acanthamoeba and acquirement of biologically meaningful genotyping information. We anticipate that the newly developed detection method will contribute to the precise estimation, evaluation, and reduction of the contamination risk of pathogenic Acanthamoeba spp., which is regularly found in the water resources utilised for domestic purposes.
Assuntos
Acanthamoeba/isolamento & purificação , Monitoramento Ambiental/métodos , Técnicas de Genotipagem , Reação em Cadeia da Polimerase/métodos , Rios/parasitologia , Acanthamoeba/genéticaRESUMO
Pathogenic free-living amoebae, most notably Acanthamoeba spp., are important pathogens of the human cornea. The importance of infection with free-living amoebae in cats with keratitis is currently unclear. The aim of this study was to determine the frequency of amoeba detection in corneas of cats with naturally-acquired keratitis and in the ocular surface microflora of cats without ocular disease. Clinical ophthalmic and in vivo corneal confocal microscopic examinations were performed on 60 cats with keratitis. Corneal scrapings were analyzed by amoeba culture; cytological evaluation; and Acanthamoeba, Hartmannella, and Vahlkampfia PCR assays. Following ophthalmic examination, conjunctival specimens collected from 60 cats without clinically apparent ocular disease were analyzed similarly. In one cat with ulcerative keratitis, amoeba cysts and trophozoites were detected by in vivo corneal confocal microscopy; an Acanthamoeba sp. was isolated from corneal specimens and detected by Acanthamoeba PCR assay; and suppurative corneal inflammation was present cytologically. An Acanthamoeba sp. was isolated from conjunctival specimens from one cat without clinically apparent ocular disease, but with suppurative inflammation demonstrated cytologically. Both Acanthamoeba isolates belonged to the T4 genotype. Naegleria-like amoebae were isolated in samples from two cats with keratitis and seven cats without clinical ocular disease, but amoebae were not detected by the other assays in these samples. Amoeba detection by culture was significantly (P = 0.01) associated with cytologically diagnosed corneoconjunctival inflammation. This study identified naturally-acquired Acanthamoeba keratitis in cats. Detection of Naegleria-like amoebae in samples from cats with and without keratitis is of uncertain pathological significance.
Assuntos
Amoeba/isolamento & purificação , Doenças do Gato/parasitologia , Córnea/parasitologia , Ceratite/veterinária , Acanthamoeba/classificação , Acanthamoeba/isolamento & purificação , Ceratite por Acanthamoeba/parasitologia , Ceratite por Acanthamoeba/veterinária , Amoeba/classificação , Animais , Gatos , Córnea/patologia , Feminino , Ceratite/parasitologia , MasculinoRESUMO
Accurate and rapid diagnosis of Acanthamoeba keratitis (AK) is difficult. Although the diagnostic procedure for AK has improved, further development and effective diagnostic tool utilization for AK need to continue. Chorismate mutase is a key regulatory enzyme involved in the shikimate pathway, a metabolic pathway absent in mammals but central for amino acid biosynthesis in bacteria, fungi, algae, and plants. In this study, we describe the identification and production of a polyclonal peptide antibody targeting chorismate mutase secreted by A. castellanii, which could be used for AK diagnosis. Western blot was performed using the protein lysates and conditioned media of the human corneal epithelial (HCE) cells, non-pathogenic Acanthamoeba, pathogenic Acanthamoeba, clinical isolate of Acanthamoeba spp., and other causes of keratitis such as Fusarium solani, Pseudomonas aeruginosa, and Staphylococcus aureus. Polyclonal antibodies raised against A. castellanii chorismate mutase specifically interacted with lysates of Acanthamoeba origin and their culture media, while such interactions were not observed from other samples. Acanthamoeba-specificity of chorismate mutase was also confirmed using immunocytochemistry after co-culturing Acanthamoeba with HCE cells. Specific binding of the chorismate mutase antibody to Acanthamoeba was observed, which were absent in the case of HCE cells. These results indicate that the chorismate mutase antibody of Acanthamoeba may serve as a method for rapid and differential Acanthamoeba identification.
Assuntos
Ceratite por Acanthamoeba , Acanthamoeba , Anticorpos/imunologia , Corismato Mutase/imunologia , Peptídeos/imunologia , Acanthamoeba/imunologia , Acanthamoeba/isolamento & purificação , Ceratite por Acanthamoeba/diagnóstico , Ceratite por Acanthamoeba/parasitologia , Linhagem Celular , Células Epiteliais , HumanosRESUMO
Acanthamoeba is an opportunistic protozoan pathogen which is found in diverse environment worldwide. Being ubiquitous nature of this amoeba we come across it in our daily life. Acanthamoeba species are recognized as human pathogens; that may cause blinding keratitis and rare but fatal granulomatous encephalitis involving central nervous system. To date, there is not a single report in literature demonstrating anti-Acanthamoeba antibodies among the Saudi population, and thus aim of the present study. Using ELISA, we identified the antibody level in the local population. Our results represent the secretory IgA antiAcanthamoeba in mucosal secretions from 133 individuals aged 15-60 years. The antiAcanthamoeba antibody prevalence rate was > 80%, and no considerable differences were observed between prevalence in males (80.28%) and that in females (80.64%). In addition, environmental sources (soil and water) from the environment of the participants in our study were evaluated for amoeba incidence. The amoeba was identified by morphological characteristics of cysts or trophozoites on non-nutrient agar plates grown with E. coli. Overall, 58.75% of samples from water and 32.85% of those from soil were culture positive for outgrowth of amoeba on non-nutrient agar plates. Furthermore, PCR was carried out with genus-specific primers to confirm the presence of Acanthamoeba DNA. Our results revealed that about 68% of cultures from water and 43% of those from soil were successfully amplified and proved to be amoeba DNA. Interestingly, a few samples yielded more than one product, which suggests that some other amoebic species may be present in the same sample (MAC-W1 and MADW1). To the best of our knowledge, we described for the first time the amoeba isolation from the participant's close environment and antibodies level among Saudi population. Our future studies will be focused on additional molecular characterization of isolated amoeba and their pathogenic potential which could be a possible threat for the community.
Assuntos
Acanthamoeba/isolamento & purificação , Anticorpos Antiprotozoários/isolamento & purificação , Imunoglobulina A/isolamento & purificação , Adolescente , Adulto , DNA de Protozoário/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saliva/química , Arábia Saudita , Solo/parasitologia , Água/parasitologia , Adulto JovemRESUMO
PURPOSE: To determine the prevalence and reasons for delays in diagnosis in patients with Acanthamoeba keratitis (AK) presenting to Wilmer Eye Institute, Baltimore, Maryland. METHODS: This retrospective study analysed all patients with culture-positive AK seen between 2012 and 2019 at a tertiary referral centre. Patient demographic information, clinical history, risk factors, symptom duration, referral patterns, slit lamp examination findings, visual acuity and need for surgery were collected. RESULTS: The study included 45 eyes of 43 patients. On average, patients were symptomatic for 52.6 days before culture collection. Thirty-one percent of patients were diagnosed within 28 days of symptom onset while 69% were diagnosed after 28 days. Before presentation to a tertiary care centre, 69% of patients were evaluated by an ophthalmologist outside of this institution and 27% were evaluated by a provider other than an ophthalmologist. AK was most commonly misdiagnosed as herpetic keratitis, occurring in 38% of patients. The strongest risk factor for AK was contact lens use. Only 11% of patients presented with the classic ring infiltrate and 82% had pain. Patients with an early versus late diagnosis had a mean Snellen visual acuity (VA) of 20/224 versus 20/296 at presentation (p = 0.33) and a mean Snellen VA of 20/91 versus 20/240 at final visit (p = 0.07). 11% of patients required a therapeutic penetrating keratoplasty. CONCLUSION: Delayed diagnosis of AK in our cohort occurred due to a misdiagnosis as herpetic keratitis, non-specific clinical signs including the lack of pain in a number of patients, and a delay in referral to a tertiary care centre. Any contact lens wearer with an atypical keratitis should be referred promptly for Acanthamoeba cultures.
Assuntos
Ceratite por Acanthamoeba/diagnóstico , Acanthamoeba/isolamento & purificação , Córnea/parasitologia , Diagnóstico Tardio , Infecções Oculares Parasitárias/diagnóstico , Centros de Atenção Terciária/estatística & dados numéricos , Acuidade Visual , Ceratite por Acanthamoeba/epidemiologia , Ceratite por Acanthamoeba/parasitologia , Adulto , Córnea/diagnóstico por imagem , Infecções Oculares Parasitárias/epidemiologia , Infecções Oculares Parasitárias/parasitologia , Feminino , Seguimentos , Humanos , Masculino , Microscopia Confocal , Prevalência , Estudos Retrospectivos , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
PURPOSE: In our report, we present a suspected case of donor-derived Acanthamoeba keratitis after deep anterior lamellar keratoplasty. To the authors' knowledge, there have been no confirmed cases of Acanthamoeba keratitis transmission through corneal transplantation. METHODS: Deep anterior lamellar keratoplasty was performed on the right eye of a 33-year-old man with severe bilateral keratoconus and an intolerance to all forms of contact lenses. The postoperative visual acuity deteriorated, while inflammation, rising ocular pressure, increasing corneal thickness, and severe eye pain began to present. Confocal imaging revealed hyperreflective cysts and trophozoite figures representative of amoebic keratitis. Despite an additional penetrating keratoplasty, antiamoeba therapy, and corneal crosslinking, the patient's condition worsened, resulting in stromal melt and corneal perforation. Emergent combined surgery of temporary keratoprosthesis, vitrectomy, lensectomy, and iridectomy was performed, along with Ahmed valve shunt placement and another penetrating keratoplasty. RESULTS: The infection was resistant to aggressive antiamoeba therapy, but after the emergent combined surgery, the graft re-epithelialized quickly and has since remained clear, with no presence of keratitis. CONCLUSIONS: Several signs led us to believe that this case was donor-derived. There was little opportunity for graft exposure to the amoeba, and deep amoebic cysts and trophozoites were present on postoperative week 1-a highly unusual time course and depth of invasion for primary amoebic infection. In addition, pathological analysis revealed cysts only within the confines of the donor tissue and none in the recipient; Acanthamoeba cysts would have been present in the recipient rim tissue if the infection originated from the patient himself.
Assuntos
Ceratite por Acanthamoeba/transmissão , Transplante de Córnea/efeitos adversos , Transmissão de Doença Infecciosa , Doadores de Tecidos , Acanthamoeba/isolamento & purificação , Ceratite por Acanthamoeba/diagnóstico , Ceratite por Acanthamoeba/cirurgia , Adulto , Substância Própria/parasitologia , Feminino , Humanos , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Acuidade VisualRESUMO
Acanthamoeba are free-living amoebae that cause granulomatous amoebic encephalitis and keratitis. In this study, we aimed to isolate and identify Acanthamoeba from air conditioning systems using in vitro cell culture and polymerase chain reaction assays. We also estimated the pathogenicity of the isolates by measuring their thermotolerance and studying mice models inoculated with these isolates. Of the 80 dust samples acquired, 41 (51.25%) were found to be positive for Acanthamoeba spp. using in vitro cell culture and the results were validated using PCR. Out of these 41 samples, 27 (65.9%) were thermotolerant and 16 (39%) samples could infect mice and cause histopathological effects. Highly pathogenic Acanthamoeba isolates were characterized by their thermotolerance and the ability to disseminate in all organs after infection, causing early death of infected animals. Our study thus validated the presence of pathogenic isolates of Acanthamoeba in air conditioners that may be potentially infectious to humans.
Assuntos
Acanthamoeba/isolamento & purificação , Ar Condicionado , Acanthamoeba/genética , Acanthamoeba/patogenicidade , Amebíase/mortalidade , Amebíase/fisiopatologia , Animais , Modelos Animais de Doenças , Poeira/análise , Egito , Contaminação de Equipamentos , Humanos , Camundongos , Reação em Cadeia da Polimerase , RNA Ribossômico 18S/análiseRESUMO
PURPOSE: To report a cluster of postoperative Acanthamoeba endophthalmitis after routine cataract surgeries. METHODS: A brief summary of sentinel events leading to the referral of 4 patients of postoperative endophthalmitis to our hospital is followed by clinical descriptions and the various diagnostic approaches and interventions used. Genotyping and phylogenetic analysis are also discussed. RESULTS: Four cases of postoperative cluster endophthalmitis, presumed to be bacterial and treated as such, were referred to our hospital. The presence of an atypical ring infiltrate in the first case facilitated the diagnosis of Acanthamoeba endophthalmitis. All patients had vitritis, corneal involvement, and scleral inflammation. Multiple diagnostic methods, such as corneal scrapings, confocal microscopy, aqueous and vitreous taps, scleral abscess drainage, histopathological studies, polymerase chain reaction, and genotyping and phylogenetic analyses of isolated Acanthamoeba, were used to confirm the diagnosis of endophthalmitis and to establish the extent of ocular involvement. Various medical and therapeutic interventions used to control the infections were also documented. The isolated Acanthamoeba were confirmed as belonging to the T10 genotype, an environmentally and clinically rare variety. CONCLUSIONS: This is the first report of a cluster of postoperative T10 genotype Acanthamoeba endophthalmitis, occurring after routine cataract surgery in immunocompetent individuals. Contrary to current perceptions, a rapidly evolving infection can occur with Acanthamoeba.
Assuntos
Acanthamoeba/genética , Amebíase/parasitologia , Endoftalmite/parasitologia , Infecções Oculares Parasitárias/parasitologia , Complicações Pós-Operatórias/parasitologia , Acanthamoeba/isolamento & purificação , Amebíase/diagnóstico , Amebíase/tratamento farmacológico , Antiprotozoários/uso terapêutico , Humor Aquoso/parasitologia , Extração de Catarata , Córnea/parasitologia , DNA de Protozoário/genética , DNA Ribossômico/genética , Hotspot de Doença , Endoftalmite/diagnóstico , Endoftalmite/tratamento farmacológico , Infecções Oculares Parasitárias/diagnóstico , Infecções Oculares Parasitárias/tratamento farmacológico , Feminino , Técnicas de Genotipagem , Humanos , Masculino , Microscopia Confocal , Filogenia , Reação em Cadeia da Polimerase , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/tratamento farmacológico , RNA Ribossômico 18S/genéticaRESUMO
Free-living amoeba (FLA) research in the Philippines is still in its infancy but has, by far, demonstrated the presence of potentially pathogenic species. Acanthamoeba may cause sight-threatening and central nervous system infections to humans, yet its epidemiologic distribution from local environmental sources is yet to be defined. The present study aimed to provide a baseline epidemiologic distribution of Acanthamoeba spp. in freshwater systems in the Philippines and establish potential pathogenicity of isolates through thermo-tolerance assay. A total of 63 water samples were collected from 13 freshwater systems all over the Philippine archipelago. The low-volume (50 ml) water samples were processed and cultured on non-nutrient agar lawned with Escherichia coli and observed for amoebic growth using light microscopy. Amoebic culture demonstrated 14.28% (9/63) positivity while further molecular testing of culture-positive plates using Acanthamoeba-specific primers demonstrated 100% (9/9) confirmation of Acanthamoeba species. Genotyping of Acanthamoeba isolates revealed T1, T3, T4, T5, T7, T11, and T15 genotypes. Thermo-tolerance assay demonstrated that T5 and T7 genotypes were potentially pathogenic strains. The evidence of environmental distribution of Acanthamoeba spp. in the freshwater systems in the Philippines and thermo-tolerance profile of isolates are significant aspects of amoeba study in public health and calls for initiatives in the dissemination of relevant information and the expansion of knowledge, awareness, and policies on pathogenic waterborne amoeba to mitigate, prevent, detect, and report cases of human infections.
Assuntos
Acanthamoeba/isolamento & purificação , Acanthamoeba/fisiologia , Água Doce/parasitologia , Acanthamoeba/genética , Acanthamoeba/crescimento & desenvolvimento , DNA de Protozoário/genética , Monitoramento Ambiental , Genótipo , Humanos , Filipinas , TermotolerânciaRESUMO
A collection of N-substituted quinolin-2(1H)-ones were screened against a panel of clinically relevant protozoa (Leishmania, Trypanosoma and Acanthamoeba). Three quinolin-2(1H)-one compounds were identified as selective anti-Acanthamoeba agents. Further assessment revealed that these compounds were active against both trophozoite and cyst forms of A. castellanii Neff, and caused protozoa death via apoptosis. The data presented herein identify N-acyl quinolin-2(1H)-ones as a promising new class of selective anti-Acanthamoeba agents.
Assuntos
Ceratite por Acanthamoeba/tratamento farmacológico , Acanthamoeba/efeitos dos fármacos , Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Quinolonas/farmacologia , Trypanosoma/efeitos dos fármacos , Acanthamoeba/isolamento & purificação , Antiprotozoários/síntese química , Antiprotozoários/química , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Leishmania/isolamento & purificação , Estrutura Molecular , Testes de Sensibilidade Parasitária , Quinolonas/síntese química , Quinolonas/química , Relação Estrutura-Atividade , Trypanosoma/isolamento & purificaçãoRESUMO
Water reservoirs are important manmade structures providing water security to deliver clean and safe water for drinking and other purposes to the community. Eighty water samples were collected from Magat and Ipo water reservoirs using purposive sampling between November 2018 and January 2019. Water samples were collected in sterile containers for testing. The samples were cultured in non-nutrient agar and lawned with Escherichia coli and incubated at 33 °C. Twelve out of the 80 (15%) water samples were positive for amoebic growth. Light and scanning electron microscopy (SEM) revealed double-walled cystic stages and were initially identified as Acanthamoeba spp. based on morphological characteristic in reference to Page's established criteria. Their extracted DNAs were used in polymerase chain reaction using JDP1 and JDP2 primers and confirmed the presence of Acanthamoeba DNA in agarose gel electrophoresis. Aligned sequences from PCR products were deposited in GenBank under accession numbers MK886460, MK909919, MK905437, MK910997, MK911021 and MK886514. The presence of potentially pathogenic Acanthamoeba spp. in water reservoirs is considered a potential risk for public health, requiring appropriate processing of water in treatment plants.
Assuntos
Acanthamoeba/isolamento & purificação , Água Doce/parasitologia , Abastecimento de Água , Filipinas , Reação em Cadeia da PolimeraseRESUMO
The present study aims to investigate the occurrence of free living amoeba (FLA) in water resources (rivers and tap water) in Samsun in the Black Sea. The presence of Acanthamoeba spp. was confirmed in 98 of 192 water samples collected from 32 sites of Samsun province (Samsun centre, Terme, Carsamba, Tekkekoy, Bafra) by PCR. Acanthamoeba spp. were found in 15/36 river samples from Samsun, in 58/90 from Terme, in 12/30 from Carsamba, in 7/18 from Tekkekoy and in 6/18 from Bafra. No Acanthamoeba species were detected in tap water samples. The highest rate in river waters contaminated with Acanthamoeba species was in Terme followed by Samsun centre (41.7%), Carsamba (40%), Tekkekoy (38.9%) and Bafra districts (33.3%), respectively. The result of the subsequent sequence analysis showed Haplotype I (A. triangularis) in 5%, Haplotype II (A. polyphaga) in 29.6%, Haplotype III (Acanthamoeba spp.) in 62% and Haplotype IV (A. lenticulata) in 3%. The most common genotype was Acanthamoeba T4 (Acanthamoeba spp., A. polyphaga, A. triangularis) and T5 genotype was also found in 3%. The T4 genotype is the most common genotype associated with Acanthamoeba keratitis (AK) worldwide; therefore, humans and animals living in the area are at risk after contact with such waters.