RESUMEN
A key factor in the development of obesity is the overconsumption of fatty foods, which, in addition to facilitating weight gain, alters neuronal structures within brain reward circuitry. Our previous work demonstrates that sustained consumption of a high-fat diet (HFD) attenuates spine density in the prefrontal cortex (PFC). Whether HFD promotes structural adaptation among inhibitory cells of the PFC is presently unknown. One structure of interest is the perineuronal net (PNN), a specialized extracellular matrix surrounding, primarily, parvalbumin-containing GABAergic interneurons. PNNs contribute to synaptic stabilization, protect against oxidative stress, regulate the ionic microenvironment within cells, and modulate regional excitatory output. To examine diet-induced changes in PNNs, we maintained rats on one of three dietary conditions for 21 days: ad libitum chow, ad libitum 60% high fat (HF-AL), or limited-access calorically matched high fat (HF-CM), which produced no significant change in weight gain or adiposity with respect to chow controls. The PNN "number" and intensity were then quantified in the prelimbic (PL-PFC), infralimbic (IL-PFC), and ventral orbitofrontal cortex (OFC) using Wisteria floribunda agglutinin (WFA). Our results demonstrated that fat exposure, independent of weight gain, induced a robust decrease in the PNN intensity in the PL-PFC and OFC and a decrease in the PNN number in the OFC.
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Dieta Alta en Grasa/efectos adversos , Red Nerviosa/fisiopatología , Corteza Prefrontal/fisiopatología , Animales , Dieta Alta en Grasa/tendencias , Interneuronas/patología , Masculino , Red Nerviosa/patología , Nervios Periféricos/patología , Nervios Periféricos/fisiopatología , Corteza Prefrontal/patología , Ratas , Ratas Sprague-DawleyRESUMEN
Dientamoeba fragilis is a common enteropathogen of humans. Recently a cyst stage of the parasite was described in an animal model; however, no cyst stage has been described in detail from clinical samples. We describe both cyst and precystic forms from human clinical samples.
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Dientamoeba/citología , Dientamebiasis/parasitología , Esporas Protozoarias/citología , Dientamoeba/fisiología , Humanos , Microscopía , Esporas Protozoarias/fisiologíaRESUMEN
Genetic variants in ATP7A are associated with a spectrum of X-linked disorders. In descending order of severity, these are Menkes disease, occipital horn syndrome, and X-linked distal spinal muscular atrophy. After 30 years of diagnostic investigation, we identified a deep intronic ATP7A variant in four males from a family affected to variable degrees by a predominantly skeletal phenotype, featuring bowing of long bones, elbow joints with restricted mobility which dislocate frequently, coarse curly hair, chronic diarrhoea, and motor coordination difficulties. Analysis of whole genome sequencing data from the Genomics England 100,000 Genomes Project following clinical re-evaluation identified a deep intronic ATP7A variant, which was predicted by SpliceAI to have a modest splicing effect. Using a mini-gene splicing assay, we determined that the intronic variant results in aberrant splicing. Sanger sequencing of patient cDNA revealed ATP7A transcripts with exon 5 skipping, or inclusion of a novel intron 4 pseudoexon. In both instances, frameshift leading to premature termination are predicted. Quantification of ATP7A mRNA transcripts using a qPCR assay indicated that the majority of transcripts (86.1 %) have non-canonical splicing, with 68.0 % featuring exon 5 skipping, and 18.1 % featuring the novel pseudoexon. We suggest that the variability of the phenotypes within the affected males results from the stochastic effects of splicing. This deep intronic variant, resulting in aberrant ATP7A splicing, expands the understanding of intronic variation on the ATP7A-related disease spectrum.
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Cutis Laxo , Síndrome de Ehlers-Danlos , Humanos , Masculino , ATPasas Transportadoras de Cobre/genética , Cutis Laxo/genética , Síndrome de Ehlers-Danlos/genética , Mutación , Fragmentos de Péptidos/genética , FenotipoRESUMEN
Blastocystis is one of the most common enteric parasites present in humans. There is still much uncertainty about the pathogenic potential of this parasite, and it was suggested that its pathogenicity could be subtype-related. This report aimed to study 98 Blastocystis isolates found in human stool specimens to identify the subtypes present and carry out phylogenetic analysis on these isolates. This study also aimed to show the relationship between subtype and symptoms. Five-hundred and thirteen stool samples were submitted to five different diagnostic techniques for the detection of Blastocystis. Polymerase chain reaction (PCR)-positive samples were then sequenced and the small subunit (SSU) rDNA sequences were aligned and submitted to phylogenetic analysis. Ninety-eight samples were positive by any of the diagnostic methods for Blastocystis and 96 were positive by PCR. There were seven different subtypes (1, 2, 3, 4, 6, 7 and 8) identified by PCR and sequencing. This is the first large-scale study to examine the occurrence of Blastocystis in Australia. This study reports the high incidence of subtype 3 (44 %) in this population and discusses the emerging idea of subtype-dependent pathogenicity.
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Infecciones por Blastocystis/epidemiología , Infecciones por Blastocystis/parasitología , Blastocystis/clasificación , Blastocystis/patogenicidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Blastocystis/aislamiento & purificación , Infecciones por Blastocystis/patología , Niño , Preescolar , Análisis por Conglomerados , ADN Protozoario/química , ADN Protozoario/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Heces/parasitología , Femenino , Genotipo , Humanos , Lactante , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
Dientamoeba fragilis is a commonly encountered trichomonad which has been implicated as a cause of gastrointestinal disease in humans. Despite the frequency of reports recording infections with this parasite, little research has been undertaken in terms of antimicrobial susceptibility. The aim of this study was to evaluate the susceptibility of D. fragilis to several commonly used antiparasitic agents: diloxanide furoate, furazolidone, iodoquinol, metronidazole, nitazoxanide, ornidazole, paromomycin, secnidazole, ronidazole, tetracycline, and tinidazole. Antibiotic susceptibility testing was performed on four clinical strains of D. fragilis, designated A, E, M, and V, respectively. Molecular testing followed, and all strains were determined to be genotype 1. The activities of antiprotozoal compounds at concentrations ranging from 2 µg/ml to 500 µg/ml were determined via cell counts of D. fragilis trophozoites grown in dixenic culture. Minimum lethal concentrations (MLCs) were as follows: ornidazole, 8 to 16 µg/ml; ronidazole, 8 to 16 µg/ml; tinidazole, 31 µg/ml; metronidazole, 31 µg/ml; secnidazole, 31 to 63 µg/ml; nitazoxanide, 63 µg/ml; tetracycline, 250 µg/ml; furazolidone, 250 to 500 µg/ml; iodoquinol, 500 µg/ml; paromomycin, 500 µg/ml; and diloxanide furoate, >500 µg/ml. This is the first study to report the profiles of susceptibility to a wide range of commonly used treatments for clinical isolates of D. fragilis. Our study indicated 5-nitroimidazole derivatives to be the most active compounds in vitro against D. fragilis.
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Antiprotozoarios/farmacología , Dientamoeba/efectos de los fármacos , Dientamebiasis/tratamiento farmacológico , Nitroimidazoles/farmacología , Técnicas de Tipificación Bacteriana , Recuento de Células , Técnicas de Cultivo de Célula , Dientamoeba/genética , Dientamoeba/aislamiento & purificación , Dientamebiasis/parasitología , Relación Dosis-Respuesta a Droga , Genotipo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Trofozoítos/efectos de los fármacosRESUMEN
There are many neglected nonenteric protozoa able to cause serious morbidity and mortality in humans, particularly in the developing world. Diseases caused by certain protozoa are often more severe in the presence of HIV. While information regarding neglected tropical diseases caused by trypanosomatids and Plasmodium is abundant, these protozoa are often not a first consideration in Western countries where they are not endemic. As such, diagnostics may not be available in these regions. Due to global travel and immigration, this has become an increasing problem. Inversely, in certain parts of the world (particularly sub-Saharan Africa), the HIV problem is so severe that diseases like microsporidiosis and toxoplasmosis are common. In Western countries, due to the availability of highly active antiretroviral therapy (HAART), these diseases are infrequently encountered. While free-living amoebae are rarely encountered in a clinical setting, when infections do occur, they are often fatal. Rapid diagnosis and treatment are essential to the survival of patients infected with these organisms. This paper reviews information on the diagnosis and treatment of nonenteric protozoal diseases in immunocompromised people, with a focus on patients infected with HIV. The nonenteric microsporidia, some trypanosomatids, Toxoplasma spp., Neospora spp., some free-living amoebae, Plasmodium spp., and Babesia spp. are discussed.
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Huésped Inmunocomprometido , Infecciones por Protozoos/inmunología , Infecciones por Protozoos/parasitología , África del Sur del Sahara , Amoeba/inmunología , Amoeba/patogenicidad , Terapia Antirretroviral Altamente Activa , Femenino , Infecciones por VIH/parasitología , Infecciones por VIH/fisiopatología , Humanos , Plasmodium/inmunología , Plasmodium/patogenicidad , Embarazo , Infecciones por Protozoos/diagnóstico , Infecciones por Protozoos/terapia , Trypanosomatina/inmunología , Trypanosomatina/patogenicidadRESUMEN
INTRODUCTION: Bladder exstrophy-epispadias complex (BEEC) comprises a spectrum of anterior midline congenital malformations, involving the lower urinary tract. BEEC is usually sporadic, but families with more than one affected member have been reported, and a twin concordance study supported a genetic contribution to pathogenesis. Moreover, diverse chromosomal aberrations have been reported in a small subset of individuals with BEEC. The commonest are 22q11.2 microduplications, identified in approximately 3% of BEEC index cases. OBJECTIVES: We aimed to refine the chromosome 22q11.2 locus, and to determine whether the encompassed genes are expressed in normal developing and mature human urinary bladders. RESULTS: Using DNA from an individual with CBE, the 22q11.2 duplicated locus was refined by identification of a maternally inherited 314 kb duplication (chr22:21,147,293-21,461,017), as depicted in this image. Moreover, the eight protein coding genes within the locus were found to be expressed during normal developing and mature bladders. To determine whether duplications in any of these individual genes were associated with CBE, we undertook copy number analyses in 115 individuals with CBE without duplications of the whole locus. No duplications of individual genes were found. DISCUSSION: The current study has refined the 22q11.2 locus associated with BEEC and has shown that the eight protein coding genes are expressed in human bladders both during antenatal development and postnatally. Nevertheless, the precise biological explanation as to why duplication of the phenocritical region of 22q11 confers increased susceptibility to BEEC remains to be determined. The fact that individuals with CBE without duplications of the whole locus also lacked duplication of any of the individual genes suggests that in individuals with BEEC and duplication of the 22q11.2 locus altered dosage of more than one gene may be important in BEEC etiology. CONCLUSIONS: The study has refined the 22q11.2 locus associated with BEEC and has shown that the eight protein coding genes within this locus are expressed in human bladders.
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Extrofia de la Vejiga , Epispadias , Extrofia de la Vejiga/genética , Extrofia de la Vejiga/patología , Cromosomas/metabolismo , Epispadias/genética , Epispadias/patología , Femenino , Humanos , Embarazo , Vejiga Urinaria/anomalíasRESUMEN
The aim of this study was to describe the first development and evaluation of a multiplex tandem PCR (MT-PCR) assay for the detection and identification of 4 common pathogenic protozoan parasites, Cryptosporidium spp., Dientamoeba fragilis, Entamoeba histolytica, and Giardia intestinalis, from human clinical samples. A total of 472 fecal samples submitted to the Department of Microbiology at St. Vincent's Hospital were included in the study. The MT-PCR assay was compared to four real-time PCR (RT-PCR) assays and microscopy by a traditional modified iron hematoxylin stain. The MT-PCR detected 28 G. intestinalis, 26 D. fragilis, 11 E. histolytica, and 9 Cryptosporidium sp. isolates. Detection and identification of the fecal protozoa by MT-PCR demonstrated 100% correlation with the RT-PCR results, and compared to RT-PCR, MT-PCR exhibited 100% sensitivity and specificity, while traditional microscopy of stained fixed fecal smears exhibited sensitivities and specificities of 56% and 100% for Cryptosporidium spp., 38% and 99% for D. fragilis, 47% and 97% for E. histolytica, and 50% and 100% for G. intestinalis. No cross-reactivity was detected in 100 stool samples containing various other bacterial, viral, and protozoan species. The MT-PCR assay was able to provide rapid, sensitive, and specific simultaneous detection and identification of the four most important diarrhea-causing protozoan parasites that infect humans. This study also highlights the lack of sensitivity demonstrated by microscopy, and thus, molecular methods such as MT-PCR must be considered the diagnostic methods of choice for enteric protozoan parasites.
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Cryptosporidium/aislamiento & purificación , Dientamoeba/aislamiento & purificación , Entamoeba histolytica/aislamiento & purificación , Giardia lamblia/aislamiento & purificación , Parasitología/métodos , Reacción en Cadena de la Polimerasa/métodos , Infecciones por Protozoos/diagnóstico , Cryptosporidium/genética , Dientamoeba/genética , Entamoeba histolytica/genética , Heces/parasitología , Giardia lamblia/genética , Humanos , Microscopía , Infecciones por Protozoos/parasitología , Sensibilidad y EspecificidadRESUMEN
Dientamoeba fragilis is a pathogenic protozoan parasite that is implicated as a cause of human diarrhoea. A case-controlled study was conducted to determine the clinical signs associated with D. fragilis infection in children presenting to a Sydney Hospital. Treatment options are also discussed. Stool specimens were collected from children aged 15 years or younger and analysed for the presence of D. fragilis. In total, 41 children were included in the study along with a control group. Laboratory diagnosis was performed by microscopy of permanently stained, fixed faecal smears and by real-time PCR. Gastrointestinal symptoms were present in 40/41 (98%) of these children with dientamoebiasis, with diarrhoea (71%) and abdominal pain (29%) the most common clinical signs. Chronic gastrointestinal symptoms were present in 2% of cases. The most common anti-microbial used for treatment was metronidazole (n=41), with complete resolution of symptoms and clearance of parasite occurring in 85% of cases. A treatment failure rate occurred in 15% of those treated with metronidazole. Follow-up treatment comprised of an additional course of metronidazole or iodoquinol was needed in order to achieve complete resolution of infection and symptoms in this group. This study demonstrates the pathogenic potential of D. fragilis in children and as such it is recommended that all laboratories must routinely test for this organism and treat if detected.
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Dientamebiasis/diagnóstico , Dientamebiasis/tratamiento farmacológico , Metronidazol/uso terapéutico , Dolor Abdominal/etiología , Adolescente , Antiprotozoarios/uso terapéutico , Australia/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Diarrea/etiología , Dientamoeba/fisiología , Dientamebiasis/complicaciones , Dientamebiasis/epidemiología , Dientamebiasis/patología , Heces/parasitología , Femenino , Humanos , Lactante , Yodoquinol/uso terapéutico , Masculino , Resultado del TratamientoRESUMEN
Globally, the number of immunosuppressed people increases each year, with the human immunodeficiency virus (HIV) pandemic continuing to spread unabated in many parts of the world. Immunosuppression may also occur in malnourished persons, patients undergoing chemotherapy for malignancy, and those receiving immunosuppressive therapy. Components of the immune system can be functionally or genetically abnormal as a result of acquired (e.g., caused by HIV infection, lymphoma, or high-dose steroids or other immunosuppressive medications) or congenital illnesses, with more than 120 congenital immunodeficiencies described to date that either affect humoral immunity or compromise T-cell function. All individuals affected by immunosuppression are at risk of infection by opportunistic parasites (such as the microsporidia) as well as those more commonly associated with gastrointestinal disease (such as Giardia). The outcome of infection by enteric protozoan parasites is dependent on absolute CD4(+) cell counts, with lower counts being associated with more severe disease, more atypical disease, and a greater risk of disseminated disease. This review summarizes our current state of knowledge on the significance of enteric parasitic protozoa as a cause of disease in immunosuppressed persons and also provides guidance on recent advances in diagnosis and therapy for the control of these important parasites.
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Huésped Inmunocomprometido , Parasitosis Intestinales/parasitología , Infecciones Oportunistas/parasitología , Infecciones por Protozoos/parasitología , Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/inmunología , Infecciones Oportunistas Relacionadas con el SIDA/parasitología , Infecciones Oportunistas Relacionadas con el SIDA/patología , Antiprotozoarios/uso terapéutico , Humanos , Parasitosis Intestinales/tratamiento farmacológico , Parasitosis Intestinales/inmunología , Parasitosis Intestinales/patología , Infecciones Oportunistas/tratamiento farmacológico , Infecciones Oportunistas/inmunología , Infecciones Oportunistas/patología , Infecciones por Protozoos/diagnóstico , Infecciones por Protozoos/tratamiento farmacológico , Infecciones por Protozoos/inmunologíaRESUMEN
Dientamoeba fragilis is a pathogenic protozoan parasite that is notoriously difficult to diagnose. The aim of this study was to determine the gold standard for laboratory detection of D. fragilis. A total of 650 human faecal samples were included in the study. All specimens underwent the following: microscopy using a permanent stain (modified iron-haematoxylin), culture using a modified Boeck and Drbohlav's medium (MBD) and TYGM-9, a conventional polymerase chain reaction (PCR) and a real-time PCR (RT-PCR). The overall prevalence of D. fragilis in the study population was 5.4% (35/650). RT-PCR detected 35 isolates, conventional PCR detected 15 isolates, MBD culture detected 14 isolates, TYGM-9 detected ten isolates, while microscopy detected 12 isolates. RT-PCR detected an additional 15 positive samples compared to the other diagnostic methods, all of which were confirmed by sequencing. When all methods were compared to each other, RT-PCR showed a sensitivity and specificity of 100 and 100%, conventional PCR 42.9 and 100%, MBD culture 40 and 100%, TYGM-9 culture 28.6 and 100%, and microscopy 34.3 and 99%, respectively. These results show that RT-PCR is the diagnostic method of choice for the detection of D. fragilis in clinical samples and, as such, should be considered as the gold standard for diagnosis.
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Técnicas de Laboratorio Clínico/métodos , Dientamoeba/aislamiento & purificación , Dientamebiasis/diagnóstico , Heces/parasitología , Microscopía/métodos , Reacción en Cadena de la Polimerasa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Técnicas de Cultivo de Célula/métodos , Niño , Preescolar , ADN Protozoario/química , ADN Protozoario/genética , Dientamoeba/citología , Dientamoeba/genética , Dientamoeba/crecimiento & desarrollo , Dientamebiasis/parasitología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
Dientamoeba fragilis is a pathogen of the human gastrointestinal tract that is a common cause of diarrhoea. A paucity of knowledge on the in vitro cultivation and cryopreservation of Dientamoeba has meant that few studies have been conducted to investigate its biology. The objective of this study was to define, for the first time, in vitro culture conditions able to support the long-term in vitro growth of Dientamoeba. Also, we aimed to define a suitable method for cryopreserving viable Dientamoeba trophozoites. A modified BD medium, TYGM-9, Loeffler's slope medium, Robinson's medium, Medium 199, Trichosel and a Tritrichomonas fetus medium were compared, using cell counts, for their ability to support the growth of D. fragilis at various temperatures and atmospheric conditions. Loeffler's slope medium supported significantly better growth compared to other media. A temperature of 42°C and a microaerophilic atmosphere were also optimum for Dientamoeba growth. To our knowledge, this is the first study to describe and compare different culture media and conditions for the growth of clinical isolates of D. fragilis. This new technology will aid the development of diagnostics for dientamoebiasis as well as facilitate large-scale sequencing projects that will fast track molecular studies on D. fragilis.
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Criopreservación/métodos , Medios de Cultivo , Dientamoeba/crecimiento & desarrollo , Dientamebiasis/parasitología , Parasitología/métodos , Animales , ADN Protozoario/análisis , ADN Protozoario/aislamiento & purificación , Dientamoeba/genética , Dientamoeba/aislamiento & purificación , Dientamoeba/metabolismo , Humanos , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , TemperaturaRESUMEN
P2/N95 filtering face piece respirators (FFRs) protect healthcare workers (HCWs) from airborne infections. This study assessed the impact of facial hair on quantitative respirator fit in 105 male HCWs, of whom 38 were clean shaven, and assessed the prevalence of male facial hair at the study facility. Only 34 (32%) male HCWs overall achieved an adequate FFR fit, including 47% of clean-shaven men. No full-bearded HCWs achieved a fit. Adequate respirator fit decreased significantly with increasing facial hair (P<0.01 for trend). Facial hair was present on 49% of male employees. This study supports quantitative fit testing prior to P2/N95 respirator use.
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Cara , Cabello , Dispositivos de Protección Respiratoria/normas , Adulto , Benchmarking , Diseño de Equipo , Femenino , Personal de Salud , Humanos , Masculino , Respiradores N95/normas , Nueva Gales del Sur , Exposición Profesional/prevención & controlRESUMEN
Microsporidia are intracellular parasites, with over 1200 species belonging to 143 genera described to date. They are opportunistic pathogens in humans and can cause chronic diarrhoea in immunosuppressed patients. Both Enterocytozoon bieneusi and Encephalitozoon intestinalis cause intestinal disease, with Enterocytozoon bieneusi more commonly identified in patients with human immunodeficiency virus (HIV) infection. In this study, intestinal microsporidial clinical isolates from patients in Sydney, Australia, were genotyped. All specimens were from HIV-infected men with low CD4(+) T-cell counts (<100 cells mm(-3)). Genotyping of the internal transcribed spacer regions of the rRNA gene showed the presence of only one genotype, the anthroponotic Enterocytozoon bieneusi genotype B strain. This study thus highlighted the limited genetic diversity among Australian Enterocytozoon bieneusi isolates, and it is hypothesized that, due to the reduced incidence of microsporidia and the subsequent reduction in the human reservoir of the anthroponotic genotype B, locally acquired intestinal microsporidiosis will rarely be seen in HIV-infected persons undergoing highly active antiretroviral therapy in the future in Australia.
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Enterocytozoon/genética , Variación Genética , Infecciones por VIH/complicaciones , Enfermedades Intestinales/microbiología , Microsporidiosis/microbiología , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , ADN de Hongos/química , ADN Ribosómico/química , Enterocytozoon/clasificación , Enterocytozoon/aislamiento & purificación , Heces/microbiología , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Humanos , Enfermedades Intestinales/complicaciones , Masculino , Microsporidiosis/complicaciones , Epidemiología Molecular , Nueva Gales del Sur , Reacción en Cadena de la Polimerasa , ARN de Hongos/genética , ARN Ribosómico/genética , Estudios RetrospectivosRESUMEN
Screening of patients is an important component for methicillin-resistant Staphylococcus aureus (MRSA) containment. The aim of this study was to determine the utility of molecular methods compared to selective agars for MRSA detection. Consecutive high risk patients (n = 200) were screened for nasal MRSA colonization using chromogenic selective agars (MRSA ID and CMRSA) as well as the BD GeneOhm MRSA (previously known as IDI-MRSA) and the Easy-Plex commercial real time PCR assays. The sensitivities of the molecular methods were similar to the BD GeneOhm MRSA (86%) and Easy-Plex (84%). The chromogenic agars, MRSA ID and CMRSA, showed sensitivities of 62% and 84%, respectively. Sensitivity was influenced by both the MRSA antibiograms and MRSA clonal type. The specificity was >98% in all methods except for the Easy-Plex assay (90%). Sensitivity of selective agars increased with 48 hours of incubation with a corresponding decrease in specificity. In conclusion, molecular detection methods for MRSA remain sensitive and rapid but are associated with greater expense.
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Técnicas Bacteriológicas/métodos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Cavidad Nasal/microbiología , Reacción en Cadena de la Polimerasa/métodos , Agar , Medios de Cultivo/química , Humanos , Sensibilidad y EspecificidadRESUMEN
The present study was conducted to compare two stool antigen detection kits with PCR for the diagnosis of Entamoeba histolytica infections by using fecal specimens submitted to the Department of Microbiology at St. Vincent's Hospital, Sydney, and the Institute of Medical and Veterinary Science, Adelaide, Australia. A total of 279 stool samples containing the E complex (E. histolytica, Entamoeba dispar, and Entamoeba moshkovskii) were included in this study. The stool specimens were tested by using two commercially produced enzyme immunoassays (the Entamoeba CELISA PATH and TechLab E. histolytica II kits) to detect antigens of E. histolytica. DNA was extracted from all of the samples with a Qiagen DNA stool mini kit (Qiagen, Hilden, Germany), and a PCR targeting the small-subunit ribosomal DNA was performed on all of the samples. When PCR was used as a reference standard, the CELISA PATH kit showed 28% sensitivity and 100% specificity. The TechLab ELISA (enzyme-linked immunosorbent assay) kit did not prove to be useful in detecting E. histolytica, as it failed to identify any of the E. histolytica samples which were positive by PCR. With the TechLab kit, cross-reactivity was observed for three specimens, one of which was positive for both E. dispar and E. moshkovskii while the other two samples contained E. moshkovskii. Quantitative assessment of the PCR and ELISA results obtained showed that the ELISA kits were 1,000 to 10,000 times less sensitive, and our results show that the CELISA PATH kit and the TechLab ELISA are not useful for the detection of E. histolytica in stool samples from patients in geographical regions where this parasite is not endemic.
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Entamoeba/aislamiento & purificación , Entamebiasis/diagnóstico , Ensayo de Inmunoadsorción Enzimática/métodos , Heces/parasitología , Reacción en Cadena de la Polimerasa/métodos , Animales , Antígenos de Protozoos/aislamiento & purificación , Australia , ADN Protozoario/genética , ADN Protozoario/aislamiento & purificación , ADN Ribosómico/genética , ADN Ribosómico/aislamiento & purificación , Entamoeba/genética , Entamoeba/inmunología , Humanos , Sensibilidad y EspecificidadRESUMEN
We report a case of prosthetic valve infective endocarditis and aortic root abscesses caused by Achromobacter xylosoxidans subsp. xylosoxidans. The patient was an intravenous drug user and had injected amphetamines using 'duck pond water' as a diluent. After surgical intervention and 6 weeks of intravenous meropenem therapy, the patient made an uneventful recovery.
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Absceso/microbiología , Achromobacter denitrificans/aislamiento & purificación , Aorta/microbiología , Válvula Aórtica/microbiología , Endocarditis Bacteriana/microbiología , Prótesis Valvulares Cardíacas/microbiología , Achromobacter denitrificans/clasificación , Achromobacter denitrificans/genética , Adulto , Bioprótesis/microbiología , Infecciones por Bacterias Gramnegativas/microbiología , Enfermedades de las Válvulas Cardíacas/microbiología , Humanos , MasculinoRESUMEN
Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder in which abdominal pain is associated with a defect or a change in bowel habits. Gut inflammation is one of the proposed mechanisms of pathogenesis. Recent studies have described a possible role for protozoan parasites, such as Blastocystis hominis and Dientamoeba fragilis, in the etiology of IBS. Dientamoeba fragilis is known to cause IBS-like symptoms and has a propensity to cause chronic infections but its diagnosis relies on microscopy of stained smears, which many laboratories do not perform, thereby leading to the misdiagnosis of dientamoebiasis as IBS. The role of B. hominis as an etiological agent of IBS is inconclusive, due to contradictory reports and the controversial nature of B. hominis as a human pathogen. Although Entamoeba histolytica infections occur predominately in developing regions of the world, clinical diagnosis of amebiasis is often difficult because symptoms of patients with IBS may closely mimic those patients with non-dysenteric amoebic colitis. Clinical manifestations of Giardia intestinalis infection also vary from asymptomatic carriage to acute and chronic diarrhoea with abdominal pain. These IBS-like symptoms can be continuous, intermittent, sporadic or recurrent, sometimes lasting years without correct diagnosis. It is essential that all patients with IBS undergo routine parasitological investigations in order to rule out the presence of protozoan parasites as the causative agents of the clinical signs.
Asunto(s)
Parasitosis Intestinales/diagnóstico , Síndrome del Colon Irritable/parasitología , Infecciones por Protozoos/diagnóstico , Animales , Infecciones por Blastocystis/complicaciones , Infecciones por Blastocystis/diagnóstico , Infecciones por Blastocystis/parasitología , Blastocystis hominis/aislamiento & purificación , Dientamoeba/aislamiento & purificación , Dientamebiasis/complicaciones , Dientamebiasis/diagnóstico , Dientamebiasis/parasitología , Disentería Amebiana/complicaciones , Disentería Amebiana/diagnóstico , Disentería Amebiana/parasitología , Entamoeba histolytica/aislamiento & purificación , Giardia lamblia/aislamiento & purificación , Giardiasis/diagnóstico , Humanos , Parasitosis Intestinales/complicaciones , Parasitosis Intestinales/parasitología , Síndrome del Colon Irritable/complicaciones , Infecciones por Protozoos/complicacionesRESUMEN
A case of sinus-orbital Rhizopus microsporus var. rhizopodiformis infection in a patient with graft versus host disease following allogeneic blood stem cell transplantation is reported. Commercially available pea straw compost used for gardening was suspected to be the source of the infection. After an initial relapse, treatment with surgical debridement, liposomal amphotericin B and posaconazole was successful.
Asunto(s)
Infecciones Fúngicas del Ojo/microbiología , Huésped Inmunocomprometido , Enfermedades Orbitales/microbiología , Enfermedades de los Senos Paranasales/microbiología , Rhizopus/aislamiento & purificación , Triazoles/uso terapéutico , Cigomicosis/tratamiento farmacológico , Cigomicosis/microbiología , Adulto , Anfotericina B/uso terapéutico , Infecciones Fúngicas del Ojo/tratamiento farmacológico , Enfermedades Hematológicas/complicaciones , Trasplante de Células Madre Hematopoyéticas , Humanos , Masculino , Enfermedades Orbitales/tratamiento farmacológico , Enfermedades de los Senos Paranasales/tratamiento farmacológico , Rhizopus/efectos de los fármacos , Suelo , Microbiología del Suelo , Trasplante Homólogo , Cigomicosis/cirugíaRESUMEN
The first isolation of Bordetella petrii from a patient with chronic suppurative mastoiditis is reported. Molecular characterization of the isolate was performed by sequencing the small-subunit rRNA gene, the Bordetella outer-membrane protein A gene (ompA) and the RisA response regulator gene (risA). This is the first reported case of B. petrii causing suppurative mastoiditis and only the second documented case of a clinically significant B. petrii isolate.