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BACKGROUND: Opportunistic Candida species causes severe infections when the human immune system is weakened, leading to high mortality. METHODS: In our study, bioinformatics analysis was used to study the high-throughput sequencing data of samples infected with four kinds of Candida species. And the hub genes were obtained by statistical analysis. RESULTS: A total of 547, 422, 415 and 405 differentially expressed genes (DEGs) of Candida albicans, Candida glabrata, Candida parapsilosis and Candida tropicalis groups were obtained, respectively. A total of 216 DEGs were obtained after taking intersections of DEGs from the four groups. A protein-protein interaction (PPI) network was established using these 216 genes. The top 10 hub genes (FOSB, EGR1, JUNB, ATF3, EGR2, NR4A1, NR4A2, DUSP1, BTG2, and EGR3) were acquired through calculation by the cytoHubba plug-in in Cytoscape software. Validated by the sequencing data of peripheral blood, JUNB, ATF3 and EGR2 genes were significant statistical significance. CONCLUSIONS: In conclusion, our study demonstrated the potential pathogenic genes in Candida species and their underlying mechanisms by bioinformatic analysis methods. Further, after statistical validation, JUNB, ATF3 and EGR2 genes were attained, which may be used as potential biomarkers with Candida species infection.
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Biomarcadores , Candidiasis/diagnóstico , Candidiasis/genética , Candidiasis/fisiopatología , Biología Computacional/métodos , Transducción de Señal/genética , Candida albicans/genética , Candida glabrata/genética , Candida tropicalis/genética , Regulación de la Expresión Génica , Variación Genética , Genotipo , HumanosRESUMEN
Candida albicans (C. albicans) is an opportunistic pathogen causing infections ranging from superficial to life-threatening disseminated infections. In a susceptible host, C. albicans is able to translocate through the gut barrier, promoting its dissemination into deeper organs. C. albicans hyphae can invade human epithelial cells by two well-documented mechanisms: epithelial-driven endocytosis and C. albicans-driven active penetration. One mechanism by which host cells protect themselves against intracellular C. albicans is termed autophagy. The protective role of autophagy during C. albicans infection has been investigated in myeloid cells; however, far less is known regarding the role of this process during the infection of epithelial cells. In the present study, we investigated the role of autophagy-related proteins during the infection of epithelial cells, including intestinal epithelial cells and gut explants, by C. albicans. Using cell imaging, we show that key molecular players of the autophagy machinery (LC3-II, PI3P, ATG16L1, and WIPI2) were recruited at Candida invasion sites. We deepened these observations by electron microscopy analyses that reveal the presence of autophagosomes in the vicinity of invading hyphae. Importantly, these events occur during active penetration of C. albicans into host cells and are associated with plasma membrane damage. In this context, we show that the autophagy-related key proteins ATG5 and ATG16L1 contribute to plasma membrane repair mediated by lysosomal exocytosis and participate in protecting epithelial cells against C. albicans-induced cell death. Our findings provide a novel mechanism by which epithelial cells, forming the first line of defense against C. albicans in the gut, can react to limit C. albicans invasion.
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Autofagia , Candida albicans/fisiología , Candidiasis/microbiología , Membrana Celular/microbiología , Células Epiteliales/microbiología , Proteína 5 Relacionada con la Autofagia/genética , Proteína 5 Relacionada con la Autofagia/metabolismo , Proteínas Relacionadas con la Autofagia/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Candida albicans/genética , Candidiasis/genética , Candidiasis/metabolismo , Candidiasis/fisiopatología , Células Epiteliales/citología , Células Epiteliales/metabolismo , Microbioma Gastrointestinal , Interacciones Huésped-Patógeno , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas de Unión a Fosfato/genética , Proteínas de Unión a Fosfato/metabolismoRESUMEN
RATIONALE: Studies on Candida infections in the central nervous system, especially in infants and young children that did or did not have postoperative surgery, are rarely reported. Thus far, intrathecal (i.t.) amphotericin B (AmB) is not routinely recommended as a therapy for Candida meningitis. We report the first case of Candida meningitis in an infant who underwent abdominal surgery and was successfully treated with i.t. and intravenous (i.v.) AmB in the mainland of China. PATIENT CONCERNS: Candida meningitis was confirmed by culture and immunoserological tests in a 1-day-old girl after surgery. She was treated with fluconazole for 1 month, but the patient's symptoms showed no improvement. DIAGNOSES: After surgery, the infant started having recurrent attacks of fever, and laboratory tests of the cerebrospinal fluid (CSF) revealed antigens of Candida tropicalis. CSF tests revealed a high total protein level and a low glucose level. She was diagnosed with a secondary Candida meningitis. INTERVENTIONS: After azole therapy failure, intrathecal and intravenous AmB therapy were used as rescue therapies. OUTCOMES: After nearly 2âmonths of AmB treatment, all repeat CSF cultures were negative, the infant was deemed stable and was discharged home, and she continued taking voriconazole orally as an outpatient. LESSONS: The combination of i.t. and i.v. administration of AmB can provide a safe and effective alternative to managing this rare but severe disease.
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Anfotericina B/farmacología , Meningitis Fúngica/tratamiento farmacológico , Administración Intravenosa/métodos , Anfotericina B/uso terapéutico , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida tropicalis/efectos de los fármacos , Candida tropicalis/patogenicidad , Candidiasis/tratamiento farmacológico , Candidiasis/fisiopatología , China , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Femenino , Humanos , Recién Nacido , Inyecciones Espinales/métodos , Meningitis Fúngica/fisiopatología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/fisiopatologíaRESUMEN
Although Candida albicans remains the main cause of candidiasis, in recent years a significant number of infections has been attributed to non-albicans Candida (NAC) species, including Candida krusei. This epidemiological change can be partly explained by the increased resistance of NAC species to antifungal drugs. C. krusei is a diploid, dimorphic ascomycetous yeast that inhabits the mucosal membrane of healthy individuals. However, this yeast can cause life-threatening infections in immunocompromised patients, with hematologic malignancy patients and those using prolonged azole prophylaxis being at higher risk. Fungal infections are usually treated with five major classes of antifungal agents which include azoles, echinocandins, polyenes, allylamines, and nucleoside analogues. Fluconazole, an azole, is the most commonly used antifungal drug due to its low host toxicity, high water solubility, and high bioavailability. However, C. krusei possesses intrinsic resistance to this drug while also rapidly developing acquired resistance to other antifungal drugs. The mechanisms of antifungal resistance of this yeast involve the alteration and overexpression of drug target, reduction in intracellular drug concentration and development of a bypass pathway. Antifungal resistance menace coupled with the paucity of the antifungal arsenal as well as challenges involved in antifungal drug development, partly due to the eukaryotic nature of both fungi and humans, have left researchers to exploit alternative therapies. Here we briefly review our current knowledge of the biology, pathophysiology and epidemiology of a potential multidrug-resistant fungal pathogen, C. krusei, while also discussing the mechanisms of drug resistance of Candida species and alternative therapeutic approaches.
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Antifúngicos/farmacología , Candida/efectos de los fármacos , Candida/patogenicidad , Candidiasis/tratamiento farmacológico , Candidiasis/epidemiología , Candidiasis/fisiopatología , Farmacorresistencia Fúngica , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
INTRODUCTION: The role of fungi in infections in immunocompromised patients is a growing problem in both diagnosis and treatment. Candida species are the most common cause of fungal, endogenous endophthalmitis and infections of the cornea. CASE STUDY: A patient was admitted to hospital due to acute inflammation of the tissue of the left orbit, 1.5 years after the corneal penetrating transplantation of the left eye with intracapsular extraction of lens and simultaneous anterior vitrectomy. The microbiological system identified: Streptococcus pyogenes, Staphylococcus aureus, and Candida glabrata in the patient. CONCLUSIONS: The factors conducive to fungal infections are: patient's old age, immune disorders and diabetes, as well as the presence of a necrotic tissue or a foreign body. All these parameters were met in this case. Only antibiotic therapy and long-term antifungal therapy, together with surgical debridement of the site of the ongoing infection produces clinical effects in such severe cases.
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Antifúngicos/uso terapéutico , Candida glabrata/aislamiento & purificación , Candidiasis/diagnóstico , Desbridamiento , Infecciones Fúngicas del Ojo/diagnóstico , Panoftalmitis/diagnóstico , Anciano , Antibacterianos/uso terapéutico , Candidiasis/microbiología , Candidiasis/fisiopatología , Infecciones Fúngicas del Ojo/microbiología , Femenino , Humanos , Panoftalmitis/microbiología , Polonia , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/terapia , Staphylococcus aureus/aislamiento & purificación , Infecciones Estreptocócicas/diagnóstico , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/terapia , Streptococcus pyogenes/aislamiento & purificación , Resultado del TratamientoRESUMEN
SIGNIFICANCE: Two fungal endophthalmitis cases demonstrate safety and efficiency of intravitreal caspofungin as a new therapy option in fungal endophthalmitis. PURPOSE: The purpose of this study was to evaluate the intravitreal application of caspofungin for the treatment of fungal endophthalmitis because rising resistance to voriconazole and amphotericin B leads to a need for new antifungal therapy options. CASE REPORT: Initially, both patients with fungal endophthalmitis underwent pars plana vitrectomy. Microbiological analysis revealed Aspergillus terreus and Candida dubliniensis, which both possess atypical resistance patterns. Caspofungin has a low bioavailability in the eye when given systemically. It was injected intravitreally into the eyes affected by fungal endophthalmitis. An injection of 100 µg of caspofungin in a volume 0.1 mL was applied repeatedly. Clinical parameters were recorded. Both eyes were stabilized by the treatment. Finally, the intraocular infections with atypical mycotic agents were eliminated. Visual acuity improved to 0.4 logMAR (20/50 Snellen) in the first case and to 1.0 logMAR (20/200 Snellen) in the second case. During the treatment course, we have not seen any toxic effects or damage of intraocular structures related to the intravitreal administration of caspofungin. CONCLUSIONS: In summary, intravitreal caspofungin was effective and well tolerated in both cases. Therefore, caspofungin seems to be a safe and effective intravitreal alternative to voriconazole and amphotericin B in fungal endophthalmitis.
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Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Barrera Hematorretinal/fisiología , Candidiasis/tratamiento farmacológico , Caspofungina/uso terapéutico , Endoftalmitis/tratamiento farmacológico , Infecciones Fúngicas del Ojo/tratamiento farmacológico , Adulto , Anciano , Anfotericina B/uso terapéutico , Aspergilosis/microbiología , Aspergilosis/fisiopatología , Aspergillus/aislamiento & purificación , Candida/aislamiento & purificación , Candidiasis/microbiología , Candidiasis/fisiopatología , Endoftalmitis/microbiología , Endoftalmitis/fisiopatología , Infecciones Fúngicas del Ojo/microbiología , Infecciones Fúngicas del Ojo/fisiopatología , Humanos , Inyecciones Intravítreas , Masculino , Agudeza Visual/fisiología , Vitrectomía , Voriconazol/uso terapéuticoRESUMEN
BACKGROUND: Candida auris is a novel Candida species, and has emerged globally as a multidrug-resistant health care-associated fungal pathogen. YouTube™ (http://www.youtube.com) as the largest free video-sharing website is increasingly used to search health information. Thus, the aim of this study was to evaluate the content, reliability and quality of YouTube™ videos regarding Candida auris infection, and to identify whether it is a useful resource for people. METHODS: The YouTube™ was used to search systematically for videos using the keywords: "Candida auris infection" and "Candida auris". Strict inclusion and exclusion criteria were used to select the videos. The videos were reviewed and scored by two independent reviewers and recorded the "title", "length", "views", "comments", "dislike", "like", "posted days" and "category of videos". The videos were categorized as "poor", "good" and "excellent" by the score. The DISCERN tool was used to assess the reliability of the YouTube™ videos. RESULTS: Seventy-six videos were included in final analysis in our study. Most videos (59.2%, 55/76) had better quality. There were no statistically significant differences between groups in respect of the number of likes, dislikes, views, comments, percentage positivity, likebility, view rate and viewers' interaction. Length and posted days were significantly associated with the classification. The videos were categorized as "educational video", "new report", "personal experience and blog entertainment" and "interview". Significant differences were found in the source of videos and the characteristics of the individuals appearing in a video between the groups. CONCLUSION: YouTube™ has striking potential to be an effective user-friendly learning interface for people to obtain information of Candida auris infection.
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Candidiasis/epidemiología , Candidiasis/fisiopatología , Exactitud de los Datos , Promoción de la Salud/métodos , Internet/normas , Medios de Comunicación Sociales/normas , Grabación en Video/normas , Humanos , Reproducibilidad de los ResultadosRESUMEN
The emerging opportunistic pathogens comprising the Candida haemulonii complex (C. haemulonii [Ch], C. duobushaemulonii [Cd] and C. haemulonii var. vulnera[Chv]) are notable for their intrinsic antifungal resistance. Different clinical manifestations are associated with these fungal infections; however, little is known about their biology and potential virulence attributes. Herein, we evaluated some surface properties of 12 clinical isolates of Ch (n = 5), Cd (n = 4) and Chv (n = 3) as well as their virulence on murine macrophages and Galleria mellonella larvae. Scanning electron microscopy demonstrated the presence of homogeneous populations among the species of the C. haemulonii complex, represented by oval yeasts with surface irregularities able to form aggregates. Cell surface hydrophobicity was isolate-specific, exhibiting high (16.7%), moderate (25.0%) and low (58.3%) hydrophobicity. The isolates had negative surface charge, except for one. Mannose/glucose- and N-acetylglucosamine-containing glycoconjugates were evidenced in considerable amounts in all isolates; however, the surface expression of sialic acid was poorly detected. Cd isolates presented significantly higher amounts of chitin than Ch and Chv. Membrane sterol and lipid bodies, containing neutral lipids, were quite similar among all fungi studied. All isolates adhered to inert surfaces in the order: polystyrene > poly-L-lysine-coated glass > glass. Likewise, they interacted with murine macrophages in a quite similar way. Regarding in vivo virulence, the C. haemulonii species complex were able to kill at least 80% of the larvae after 120 hours. Our results evidenced the ability of C. haemulonii complex to produce potential surface-related virulence attributes, key components that actively participate in the infection process described in Candida spp.
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Adhesividad/efectos de los fármacos , Antifúngicos/uso terapéutico , Candida/aislamiento & purificación , Candidiasis/tratamiento farmacológico , Candidiasis/fisiopatología , Farmacorresistencia Fúngica Múltiple/efectos de los fármacos , Virulencia/efectos de los fármacos , Arthrodermataceae/aislamiento & purificación , Brasil , Humanos , Macrófagos/efectos de los fármacos , Esporas Fúngicas/ultraestructuraRESUMEN
PURPOSE: To identify the causative microorganism of fungal endogenous endophthalmitis in our tertiary referral uveitis center and review the therapeutic role of pars plana vitrectomy in patients with fungal endogenous endophthalmitis. METHODS: Seven eyes of six cases were identified as fungal endogenous endophthalmitis through positive cultures of ocular fluids and clinical presentations. The final anatomical and functional results were evaluated. RESULTS: Four women (66.7%) and two men (33.3%) underwent vitrectomy. Control of infection was achieved early on in all cases. Candida (71.4%) and Aspergillus (28.6%) species were identified as causative fungi in patients with fungal endogenous endophthalmitis. Two patients were reoperated due to reinfection and retinal detachment, respectively. Visual acuity improved in six eyes (85.7%) and worsened in one eye (14.3%). At the final examination, the retina was flat in all cases. No eye developed phthisis bulbi. CONCLUSION: Candida species are the most common causative organisms of fungal endogenous endophthalmitis in this study. Pars plana vitrectomy in fungal endogenous endophthalmitis may enhance the treatment of infection by removing fungal elements in the vitreous and aid in diagnosis. Vitrectomy may also be an important tool in the management of vision-threatening post-infectious sequelae such as retinal detachment and reinfections.
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Aspergilosis/cirugía , Candidiasis/cirugía , Endoftalmitis/cirugía , Infecciones Fúngicas del Ojo/cirugía , Vitrectomía/métodos , Adulto , Anciano , Aspergilosis/microbiología , Aspergilosis/fisiopatología , Candidiasis/microbiología , Candidiasis/fisiopatología , Endoftalmitis/microbiología , Endoftalmitis/fisiopatología , Infecciones Fúngicas del Ojo/microbiología , Infecciones Fúngicas del Ojo/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reoperación , Desprendimiento de Retina/cirugía , Estudios Retrospectivos , Centros de Atención Terciaria , Agudeza Visual/fisiología , Cuerpo Vítreo/microbiología , Adulto JovenRESUMEN
Candidalysin is a cytolytic peptide toxin secreted by the invasive form of the human pathogenic fungus, Candida albicans. Candidalysin is critical for mucosal and systemic infections and is a key driver of host cell activation, neutrophil recruitment and Type 17 immunity. Candidalysin is regarded as the first true classical virulence factor of C. albicans but also triggers protective immune responses. This review will discuss how candidalysin was discovered, the mechanisms by which this peptide toxin contributes to C. albicans infections, and how its discovery has advanced our understanding of fungal pathogenesis and disease.
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Candida albicans/metabolismo , Candidiasis/fisiopatología , Proteínas Fúngicas/metabolismo , Interacciones Huésped-Patógeno , Micotoxinas/metabolismo , Factores de Virulencia/metabolismo , Animales , Candidiasis/microbiología , Proteínas Fúngicas/inmunología , Humanos , Micotoxinas/inmunología , Factores de Virulencia/inmunologíaRESUMEN
The fungal species Candida albicans is most frequently associated with biofilm formation in immune-compromised and medically compromised patients, and it is now firmly established that biofilm formation represents a major virulence factor during candidiasis. A growing body of evidence has demonstrated that C. albicans biofilm development is a highly regulated and coordinated process, where adhesive interactions, morphogenetic conversions, and consortial behavior play significant roles. Cells within the biofilms are protected from environmental stresses including host immune defenses and antifungal treatment, which carries important clinical consequences for the treatment of biofilm-associated infections. Dispersal of cells from biofilms represents one of the hallmarks of the biofilm life-style, and in the case of C. albicans dispersed cells are responsible for candidemia and dissemination leading to the establishment of invasive disease.
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Biopelículas/crecimiento & desarrollo , Candida albicans/crecimiento & desarrollo , Candida albicans/patogenicidad , Candidiasis/microbiología , Candidiasis/fisiopatología , Animales , Humanos , VirulenciaRESUMEN
Candida albicans, a major human fungal pathogen, can cause a wide variety of both mucosal and systemic infections, particularly in immunocompromised individuals. Multiple lines of evidence suggest a strong association between virulence and the ability of C. albicans to undergo a reversible morphological transition from yeast to filamentous cells in response to host environmental cues. Most previous studies on mechanisms important for controlling the C. albicans morphological transition have focused on signaling pathways and sequence-specific transcription factors. However, in recent years a variety of novel mechanisms have been reported, including those involving global transcriptional regulation and translational control. A large-scale functional genomics screen has also revealed new roles in filamentation for certain key biosynthesis pathways. This review article will highlight several of these exciting recent discoveries and discuss how they are relevant to the development of novel antifungal strategies. Ultimately, components of mechanisms that control C. albicans morphogenesis and pathogenicity could potentially serve as viable antifungal targets.
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Candida albicans/citología , Candida albicans/crecimiento & desarrollo , Hifa/citología , Hifa/crecimiento & desarrollo , Animales , Candida albicans/patogenicidad , Candidiasis/microbiología , Candidiasis/fisiopatología , Regulación Fúngica de la Expresión Génica , Humanos , Transducción de Señal , VirulenciaRESUMEN
INTRODUCTION: Respiratory tract Candida spp. colonization is associated with more frequent bacterial ventilator-associated pneumonia (VAP). However, this colonization could be causally related to VAP or simply reflect the immune paralysis associated with multiple organ failure. OBJECTIVE: To prospectively evaluate the relationship between Candida spp. colonization and bacterial VAP in mechanically ventilated patients with multiple organ failure. INCLUSION: Patients receiving mechanical ventilation for > 4 days and presenting multiple organ failure were included. Tracheal colonization with Candida spp. was evaluated at inclusion (day 0, D0) and every 4 days until extubation. Quantitative proximal and tracheal cultures were performed at each VAP episode. Monocyte human leukocyte antigen-DR isotype (mHLA-DR) expression and the ratio of polymononuclear leukocytes to lymphocytes were used to evaluate immunoparalysis at D0 and D7. The relationship between fungal colonization and VAP was modelled using cause-specific models for repeated events with adjustment for time-dependent confounders and immune factors. RESULTS: A total of 213 patients, with a median age of 64, simplified acute physiology score II (SAPS II) score 55 and sequential organ failure assessment (SOFA) score 10, mainly admitted for medical reasons (n = 197, 92%), were enrolled in 2012-2015. The median ICU stay was 24 days and the mortality rate was 32% (69 cases). Median mHLA-DR was 5916 Ab-bound/cell [3863-8934]; median lymphocyte count, 0.9Giga/L [0.6-1.3]; neutrophil-to-lymphocyte ratio, 10.9 [6.5-19.7]. Overall, 146 cases (68.5%) had tracheal colonization with Candida spp. An episode of VAP occurred (either for the first or only time) in 62 (29.1%) cases 5.5 days (median) after D0; a second episode occurred in 12 (5.6%) cases, 15.5 days (median) after D0. After adjustment, bronchial colonization with Candida was not associated with VAP [adjusted cause-specific hazard ratio = 0.98 (0.59-1.65), p = 0.95]. CONCLUSION: In patients with mechanical ventilation for more than 4 days and multiple organ failure, bronchial colonization with Candida spp. was not associated with VAP, even after adjustment for immune function.
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Candidiasis/complicaciones , Neumonía Asociada al Ventilador/etiología , Adulto , Bronquios/efectos de los fármacos , Bronquios/microbiología , Candida/efectos de los fármacos , Candida/patogenicidad , Candidiasis/epidemiología , Candidiasis/fisiopatología , Estudios de Cohortes , Femenino , Francia/epidemiología , Humanos , Unidades de Cuidados Intensivos/organización & administración , Unidades de Cuidados Intensivos/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Puntuaciones en la Disfunción de Órganos , Neumonía Asociada al Ventilador/epidemiología , Neumonía Asociada al Ventilador/fisiopatología , Estudios Prospectivos , Factores de Riesgo , Puntuación Fisiológica Simplificada AgudaRESUMEN
Candida osteomyelitis is a debilitating disease that is difficult to diagnose and treat. As there are no animal models or prospective studies for this uncommon infection, little is known about the pathogenesis, diagnosis, or treatment. We therefore sought to establish an animal model for the study of the pathophysiology, diagnostic modalities, and therapeutic interventions of Candida osteomyelitis. We developed a modified version of the Norden rabbit model of tibial osteomyelitis, in which the right tibia was inoculated intraoperatively with different inocula of C. albicans or normal saline as control. On days 7, 14, and 21 after inoculation, the animals underwent bone radiography, 18-fluoro-2-deoxy-D-glucose positron emission tomography combined with computed tomography (PET/CT) scan, and blood sampling for blood cultures, blood counts, erythrocyte sedimentation rate, and Candida mannan antigen serum levels. On day 21, animals were euthanized, and infected tibias harvested for culture and histology. Among eight evaluable animals inoculated with 1 × 106 to 1 × 107 cfu, histology and bone cultures established the presence of Candida osteomyelitis in seven, with a host response of neutrophils, mononuclear cells, multinucleate giant cells, fibrosis, and necrosis. Infected animals demonstrated radiological signs of osteomyelitis with significantly increased tracer uptake in 18FDG-PET/CT scans (P < .01) and elevated serum mannan levels (P < .01). All blood cultures were negative. Indices of inflammation were only slightly increased. In conclusion, we report successful establishment of a new animal model of Candida albicans osteomyelitis that may be applicable to advancing our understanding of the pathophysiology, diagnostic modalities, and treatment of this debilitating infection.
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Candida albicans/crecimiento & desarrollo , Candidiasis/patología , Modelos Animales de Enfermedad , Osteomielitis/patología , Animales , Células Sanguíneas/patología , Análisis Químico de la Sangre , Candidiasis/fisiopatología , Fluorodesoxiglucosa F18/administración & dosificación , Histocitoquímica , Masculino , Mananos/sangre , Osteomielitis/fisiopatología , Tomografía Computarizada por Tomografía de Emisión de Positrones , Conejos , Radiofármacos/administración & dosificación , Tibia/diagnóstico por imagen , Tibia/microbiología , Tibia/patologíaRESUMEN
Life-threatening systemic infections often occur due to the translocation of pathogens across the gut barrier and into the bloodstream. While the microbial and host mechanisms permitting bacterial gut translocation are well characterized, these mechanisms are still unclear for fungal pathogens such as Candida albicans, a leading cause of nosocomial fungal bloodstream infections. In this study, we dissected the cellular mechanisms of translocation of C. albicans across intestinal epithelia in vitro and identified fungal genes associated with this process. We show that fungal translocation is a dynamic process initiated by invasion and followed by cellular damage and loss of epithelial integrity. A screen of >2,000 C. albicans deletion mutants identified genes required for cellular damage of and translocation across enterocytes. Correlation analysis suggests that hypha formation, barrier damage above a minimum threshold level, and a decreased epithelial integrity are required for efficient fungal translocation. Translocation occurs predominantly via a transcellular route, which is associated with fungus-induced necrotic epithelial damage, but not apoptotic cell death. The cytolytic peptide toxin of C. albicans, candidalysin, was found to be essential for damage of enterocytes and was a key factor in subsequent fungal translocation, suggesting that transcellular translocation of C. albicans through intestinal layers is mediated by candidalysin. However, fungal invasion and low-level translocation can also occur via non-transcellular routes in a candidalysin-independent manner. This is the first study showing translocation of a human-pathogenic fungus across the intestinal barrier being mediated by a peptide toxin.IMPORTANCECandida albicans, usually a harmless fungus colonizing human mucosae, can cause lethal bloodstream infections when it manages to translocate across the intestinal epithelium. This can result from antibiotic treatment, immune dysfunction, or intestinal damage (e.g., during surgery). However, fungal processes may also contribute. In this study, we investigated the translocation process of C. albicans using in vitro cell culture models. Translocation occurs as a stepwise process starting with invasion, followed by epithelial damage and loss of epithelial integrity. The ability to secrete candidalysin, a peptide toxin deriving from the hyphal protein Ece1, is key: C. albicans hyphae, secreting candidalysin, take advantage of a necrotic weakened epithelium to translocate through the intestinal layer.
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Candida albicans/fisiología , Candidiasis/microbiología , Células Epiteliales/microbiología , Mucosa Intestinal/microbiología , Intestinos/microbiología , Apoptosis , Candida albicans/genética , Candidiasis/fisiopatología , Enterocitos/citología , Enterocitos/microbiología , Células Epiteliales/citología , Interacciones Huésped-Patógeno , Humanos , Mucosa Intestinal/citología , Intestinos/citologíaRESUMEN
Candida prosthetic endocarditis (CPE) is an uncommon and fatal complication in adults with congenital heart disease. The current guidelines for the management of fungal endocarditis recommend a combination of surgical and medical therapy. However, it still remains uncertain when surgical management in CPE patients should be performed. Therefore, the prognosis of CPE patients is very poor. Here we report a case of CPE in a 31-year-old woman who had undergone surgical repair for tetralogy of Fallot during childhood and pulmonary valve replacement at the age of 21 years. She underwent re-pulmonary valve replacement after being sufficiently sterilized with a 5-week course of antifungal medical therapy, leading to clinical improvement. In CPE patients, it is necessary to perform surgical therapy while suppressing the activity of fungi as much as possible.
Asunto(s)
Antifúngicos/administración & dosificación , Candidiasis , Endocarditis , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Prótesis Valvulares Cardíacas , Infecciones Relacionadas con Prótesis , Válvula Pulmonar , Reoperación/métodos , Tetralogía de Fallot/cirugía , Adulto , Candidiasis/etiología , Candidiasis/fisiopatología , Candidiasis/cirugía , Endocarditis/etiología , Endocarditis/microbiología , Endocarditis/fisiopatología , Endocarditis/cirugía , Femenino , Prótesis Valvulares Cardíacas/efectos adversos , Prótesis Valvulares Cardíacas/microbiología , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Pronóstico , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Relacionadas con Prótesis/fisiopatología , Infecciones Relacionadas con Prótesis/cirugía , Válvula Pulmonar/microbiología , Válvula Pulmonar/cirugía , Resultado del TratamientoRESUMEN
Polymicrobial intra-abdominal infections (IAIs) are a significant cause of morbidity and mortality, particularly when fungal pathogens are involved. Our experimental murine model of IAI involving intraperitoneal inoculation of Candida albicans and Staphylococcus aureus results in synergistic lethality (â¼80%) due to exacerbated inflammation. Monomicrobial infection results in no mortality, despite a microbial burden and dissemination similar to those in a coinfection. In the coinfection model, the immunomodulatory eicosanoid prostaglandin E2 (PGE2) was determined to be necessary and sufficient to induce mortality, implicating PGE2 as the central mediator of the amplified inflammatory response. The aim of this study was to identify key components of the PGE2 biosynthetic and signaling pathway involved in the inflammatory response and explore whether these can be targeted to prevent or reduce mortality. Using selective pharmacological inhibitors of cyclooxygenases (COX) or PGE2 receptor antagonists in the C. albicans-S. aureus IAI mouse model, we found that inhibition of COX and/or blocking of PGE2 receptor 1 (EP1) or PGE2 receptor 3 (EP3) signaling reduced proinflammatory cytokine production, promoted interleukin-10 production, reduced cellular damage in the peritoneal cavity, and, most importantly, significantly improved survival. The greatest effect on survival was obtained by the simultaneous inhibition of COX-1 activity and EP1 and EP3 receptor signaling. Importantly, early inhibition of PGE2 pathways dramatically improved the survival of fluconazole-treated mice compared with that achieved with fluconazole treatment alone. These findings indicate that COX-1 and the EP1 and EP3 receptors mediate the downstream pathological effects of PGE2 during polymicrobial IAI and may serve as effective therapeutic targets.
Asunto(s)
Candida albicans/metabolismo , Candidiasis/fisiopatología , Eicosanoides/biosíntesis , Inflamación/fisiopatología , Infecciones Intraabdominales/fisiopatología , Infecciones Estafilocócicas/fisiopatología , Staphylococcus aureus/metabolismo , Animales , Modelos Animales de Enfermedad , Inflamación/inducido químicamente , Ratones , Transducción de Señal/efectos de los fármacosRESUMEN
BACKGROUND: Candida is frequently isolated from the respiratory tract and usually reflects airway colonization. True Candida pneumonia is rare. Our aim is to document a case of Candida pneumonia confirmed by cultures, molecular techniques, and surgical lung biopsy, and to highlight a previously unreported pathologic manifestation of this infection. CASE SUMMARY: A 59-year-old man with a history of chronic obstructive pulmonary disease (COPD) presented with dry cough, low-grade fever, and progressive dyspnea. He was eventually diagnosed with sarcoidosis based on bilateral lung infiltrates and granulomas in a transbronchial biopsy. His condition worsened after immunosuppression, prompting surgical lung biopsy, which revealed suppurative granulomas containing Candida albicans, confirmed by cultures and polymerase chain reaction. Despite multiple episodes of respiratory failure and a prolonged course in intensive care, he recovered fully after antifungal therapy and is currently alive with COPD-related dyspnea 3 years after his initial presentation. CONCLUSION: Candida can rarely cause clinically significant pneumonia in adults, and should be considered in the differential diagnosis of suppurative granulomas in the lung.
Asunto(s)
Antifúngicos/uso terapéutico , Candida albicans , Candidiasis/tratamiento farmacológico , Candidiasis/patología , Neumonía/tratamiento farmacológico , Neumonía/patología , Candidiasis/fisiopatología , Cuidados Críticos , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Neumonía/microbiología , Neumonía/fisiopatologíaRESUMEN
We performed a retrospective study involving 21 patients with chronic disseminate candidiasis (CDC) and 38 patients with candidemia. Neutropenia of >2 weeks' duration was more common in those with CDC (71%) than in those with candidemia (26%, P < .001), and the azole-resistant rate in patients with CDC (5%) was lower than that in those with candidemia (29%, P = .03). Of the 21 patients with CDC, five (24%) needed adjuvant corticosteroid therapy due to persistent debilitating fever (median, 19 days). Rapid defervescence (median, 5 days) occurred after adjuvant corticosteroid therapy. However, there were no significant differences in 90-day mortality between CDC patients with and without corticosteroid therapy. Further prospective data are needed to define the role of steroids in this setting.