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1.
J Med Microbiol ; 73(10)2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39392223

RESUMO

Introduction. Fungal infections are relevant health risks for individuals with acquired immunodeficiency in the resource-limited tropics, but available surveillance data are scarce. For Candida auris and Cryptococcus spp., the evolution from environmental reservoirs to human pathogens causing life-threatening diseases is currently discussed as a public health concern in the context of climate change and limited treatment options.Gap statement. Uncovering the gastrointestinal tract as an epidemiological niche of fungi emerging from the environment into individuals for whom fungal infections are not diagnosed.Aim. To contribute to data on the local epidemiology of C. auris and Cryptococcus spp. in Western African Ghana by analysing gastrointestinal samples of Ghanaian individuals.Methodology. Four real-time PCR assays targeting C. auris and five real-time PCR assays targeting Cryptococcus spp. were applied with stool samples of 875 non-age-stratified Ghanaian HIV patients and 30 Ghanaian control individuals without known HIV infection. Also, 664 samples from Ghanaian children under 2 years of age were investigated. The true abundance of the target micro-organism was considered as unlikely in the case of one or fewer positive signals, likely in the case of two to three positive signals and highly likely in the case of four or more positive signals per sample in the real-time PCR assays.Results. The combined application of sensitive, target-specific real-time PCR assays indicates that neither C. auris, Cryptococcus neoformans complex nor Cryptococcus gattii complex were part of the gut microbiota of Ghanaian individuals with or without HIV infection.Conclusion. Despite the significant disease burden from these pathogens in immunosuppressed Ghanaian individuals, detection from gastrointestinal samples was unlikely, which should be taken into account when discussing screening strategies for these fungi of public health concern. In contrast, the detection of these fungi from such samples should not routinely be considered as commensal colonization flora.


Assuntos
Candida , Cryptococcus , Fezes , Microbioma Gastrointestinal , Infecções por HIV , Reação em Cadeia da Polimerase em Tempo Real , Humanos , Gana/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Candida/isolamento & purificação , Candida/genética , Adulto , Feminino , Masculino , Cryptococcus/isolamento & purificação , Cryptococcus/genética , Infecções por HIV/complicações , Pessoa de Meia-Idade , Fezes/microbiologia , Adulto Jovem , Criptococose/microbiologia , Criptococose/diagnóstico , Criptococose/epidemiologia , Adolescente , Candidíase/microbiologia , Candidíase/diagnóstico , Candidíase/epidemiologia , Pré-Escolar , Criança , Lactente , Idoso
2.
BMC Infect Dis ; 24(1): 1119, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379806

RESUMO

We report a case of disseminated cryptococcosis, an uncommon fungal infection predominantly affecting the lungs and central nervous system, with the rare involvement of adrenal cryptococcosis, compounded by meningitis and pneumonia. The patient, previously diagnosed with primary myelofibrosis and undergoing oral Ruxolitinib treatment, exhibited immunosuppression. Imaging via chest and abdominal CT scans revealed inflammation in the right lung's middle lobe, splenomegaly, a splenic lesion, and a left adrenal mass, initially prompting considerations of pheochromocytoma. However, unilateral adrenalectomy and subsequent pathological examination disclosed extensive infiltration by inflammatory and multinucleate giant cells, with Periodic acid-Schiff (PAS) staining confirming the diagnosis. The identification of adrenal cryptococcosis was further supported by positive adrenal pus culture and significantly elevated capsular antigens in both serum and cerebrospinal fluid, at titers of 1:2560. Following a month of oral antifungal treatment, marked reductions in capsular antigen levels were noted, to 1:640 and 1:160 in serum and cerebrospinal fluid, respectively. The patient was discharged on a regimen of oral amphotericin B, flucytosine, and fluconazole, with regular outpatient follow-ups showing no signs of recurrence or dissemination.


Assuntos
Antifúngicos , Criptococose , Humanos , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Criptococose/diagnóstico , Antifúngicos/uso terapêutico , Masculino , Hospedeiro Imunocomprometido , Pessoa de Meia-Idade , Doenças das Glândulas Suprarrenais/microbiologia , Doenças das Glândulas Suprarrenais/tratamento farmacológico , Doenças das Glândulas Suprarrenais/patologia , Glândulas Suprarrenais/patologia , Glândulas Suprarrenais/microbiologia , Terapia de Imunossupressão/efeitos adversos , Cryptococcus neoformans/isolamento & purificação , Cryptococcus neoformans/patogenicidade , Tomografia Computadorizada por Raios X
3.
BMC Infect Dis ; 24(1): 1121, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379851

RESUMO

OBJECTIVE: To develop and validate a machine learning model for predicting mortality-associated prognostic factors in order to reduce in-hospital mortality rates among HIV/AIDS patients with Cryptococcus infection in Guangxi, China. METHODS: This retrospective prognostic study included HIV/AIDS patients with cryptococcosis in the Fourth People's Hospital of Nanning from October 2011 to June 2019. Clinical features were extracted and used to train ten machine learning models, including Logistic Regression, KNN, DT, RF, Adaboost, Xgboost, LightGBM, Catboost, SVM, and NBM, to predict the outcome of HIV patients with cryptococcosis infection. The sensitivity, specificity, AUC, and F1 value were applied to assess model performance in both the testing and training sets. The optimal model was selected and interpreted. RESULTS: A total of 396 patients were included in the study. The average in-hospital mortality of HIV/AIDS patients with cryptococcosis was 12.9% from 2012 to 2019. After feature screening, 20 clinical features were selected for model construction, accounting for 93.8%, including ART, Electrolyte disorder, Anemia, and 17 laboratory tests. The RF model (AUC 0.9787, Sensitivity 0.9535, Specificity 0.8889, F1 0.7455) and the SVM model (AUC 0.9286, Sensitivity 0.7907, Specificity 0.9786, F1 0.8293) had excellent performance. The SHAP analysis showed that the primary risk factors for prognosis prediction were identified as BUN/CREA, Electrolyte disorder, NEUT%, Urea, and IBIL. CONCLUSIONS: RF and SVM machine learning models have shown promising predictive abilities for the prognosis of hospitalized HIV/AIDS patients with cryptococcosis, which can aid clinical assessment and treatment decisions for patient prognosis.


Assuntos
Criptococose , Infecções por HIV , Aprendizado de Máquina , Humanos , China/epidemiologia , Feminino , Masculino , Prognóstico , Criptococose/mortalidade , Criptococose/diagnóstico , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Infecções por HIV/complicações , Infecções por HIV/mortalidade , Mortalidade Hospitalar , Hospitalização , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/mortalidade
4.
BMC Pulm Med ; 24(1): 484, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39367350

RESUMO

Pulmonary cryptococcosis is an uncommon invasive fungal infection of the lungs seen in immunocompromised individuals but increasingly reported among the immunocompetent. We report a rare case of pulmonary cryptococcosis in an immunocompetent host highlighting its unique clinical and radiological presentation.Clinical trial number: Not applicable.


Assuntos
Antifúngicos , Criptococose , Imunocompetência , Pneumopatias Fúngicas , Tomografia Computadorizada por Raios X , Humanos , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/diagnóstico por imagem , Pneumopatias Fúngicas/tratamento farmacológico , Pneumopatias Fúngicas/microbiologia , Antifúngicos/uso terapêutico , Masculino , Pulmão/diagnóstico por imagem , Pulmão/patologia , Pessoa de Meia-Idade , Cryptococcus neoformans/isolamento & purificação
5.
Turk J Pediatr ; 66(4): 499-504, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39387422

RESUMO

BACKGROUND: Cryptococcus neoformans causes cryptococcosis, primarily affecting immunocompromised individuals, including solid-organ transplant recipients, and, less frequently, immunocompetent people. CASE: A 15-year-old male with congenital hepatic fibrosis, portal hypertension, and cirrhosis underwent orthotopic liver transplantation. He received perioperative antimicrobial and antifungal prophylaxis and continued immunosuppressive treatment. Thirty months post-transplant, he presented with fever, hypertension, and sacroiliac joint pain. Peripheral blood cultures showed C. neoformans, confirmed by pan-fungal polymerase chain reaction assay and latex agglutination tests. Despite initial treatment with intravenous (IV) fluconazole, his condition worsened, necessitating intubation for acute hypoxic respiratory failure. Magnetic resonance imaging and computed tomography scans indicated disseminated cryptococcosis with lymphadenitis, possible meningitis, and pneumonia. Treatment was escalated to IV liposomal amphotericin B and 5-flucytosine, while reducing immunosuppressive treatment. Despite negative fungal cultures on the tenth day, the patient deteriorated, developing pancreatitis, pneumonia, and massive gastrointestinal bleeding, leading to death on the 35th day of hospitalization. CONCLUSION: This case shows the severity and complexity of managing disseminated cryptococcosis in pediatric liver transplant recipients. Aggressive therapy and early identification are essential for improving outcomes in these high-risk patients.


Assuntos
Criptococose , Transplante de Fígado , Humanos , Masculino , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Transplante de Fígado/efeitos adversos , Adolescente , Antifúngicos/uso terapêutico , Evolução Fatal , Cryptococcus neoformans/isolamento & purificação , Hospedeiro Imunocomprometido , Anfotericina B
6.
BMC Infect Dis ; 24(1): 1155, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39402460

RESUMO

BACKGROUND: Cerebral venous sinus thrombosis (CVST), a serious cerebrovascular and neurological emergency, is common in pregnant individuals and accounts for approximately 0.5-1.0% of all cerebrovascular diseases. However, CVST with cryptococcal meningoencephalitis in immunocompetent pregnant patients is rare. CASE PRESENTATION: A 30-year-old woman who was 33 weeks pregnant presented with recurrent dizziness, headache, and vomiting as the main clinical manifestations, all of which were initially nonspecific. After assessment of the cerebrospinal fluid, skull computerized tomography, magnetic resonance imaging, and other laboratory and imaging examinations, the patient was diagnosed with secondary pregnancy-related CVST with cryptococcal meningoencephalitis. Despite receiving potent anticoagulant and antifungal treatment, the patient's condition deteriorated, and the patient's family opted to cease treatment. CONCLUSIONS: We present a rare case of CVST with cryptococcal meningoencephalitis in an immunocompetent pregnant patient. The difficulty of diagnosing and treating secondary pregnancy-related CVST caused by cryptococcal meningoencephalitis, as well as the great challenges faced at present are highlighted. One crucial lesson from the present case is that when clinical and imaging signs are unusual for CVST during pregnancy, it is essential to account for the possibility of other central nervous system (CNS) diseases, such as CNS infections with Cryptococcus, which may cause CVST.


Assuntos
Meningoencefalite , Complicações Infecciosas na Gravidez , Trombose dos Seios Intracranianos , Humanos , Feminino , Gravidez , Adulto , Trombose dos Seios Intracranianos/tratamento farmacológico , Trombose dos Seios Intracranianos/diagnóstico por imagem , Trombose dos Seios Intracranianos/etiologia , Trombose dos Seios Intracranianos/microbiologia , Meningoencefalite/microbiologia , Meningoencefalite/complicações , Meningoencefalite/tratamento farmacológico , Meningoencefalite/diagnóstico por imagem , Complicações Infecciosas na Gravidez/microbiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Antifúngicos/uso terapêutico , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Criptococose/complicações , Criptococose/tratamento farmacológico , Criptococose/diagnóstico por imagem , Criptococose/diagnóstico , Criptococose/microbiologia
7.
Med Mycol ; 62(9)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39237463

RESUMO

Several false positive low serum cryptococcal antigen (SCrAg) reports by lateral flow assay (LFA) were identified in late 2016 at our tertiary care hospital. After the recall and correction of the problem in the reagent, we studied the significance of SCrAg LFA ≤ 1:10 from January 2017 to October 2023. Of 20 patients with 31 samples of SCrAg LFA ≤ 1:10, 14 patients (70%) were classified as true positives, four (20%) were indeterminate, and only two (10%) patients were false positives. If a new SCrAg LFA ≤ 1:10 is detected, it should be repeated, and additional workup should be pursued.


We studied the significance of low serum cryptococcal antigen (SCrAg) titer lateral flow assay (LFA) ≤ 1:10 from January 2017 to October 2023. Of 20 patients with SCrAg LFA ≤ 1:10, only two patients (10%) were false positives. If a new SCrAg ≤ 1:10 is detected, it should be repeated, and additional workup should be done.


Assuntos
Antígenos de Fungos , Criptococose , Cryptococcus , Centros de Atenção Terciária , Humanos , Antígenos de Fungos/sangue , Antígenos de Fungos/imunologia , Criptococose/diagnóstico , Criptococose/sangue , Masculino , Feminino , Cryptococcus/imunologia , Pessoa de Meia-Idade , Reações Falso-Positivas , Adulto , Idoso , Estudos Retrospectivos
8.
Front Immunol ; 15: 1410090, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39229268

RESUMO

Immunosenescence refers to the age-related progressive decline of immune function contributing to the increased susceptibility to infectious diseases in older people. Neurocryptococcosis, an infectious disease of central nervous system (CNS) caused by Cryptococcus neoformans (C. Neoformans) and C. gattii, has been observed with increased frequency in aged people, as result of the reactivation of a latent infection or community acquisition. These opportunistic microorganisms belonging to kingdom of fungi are capable of surviving and replicating within macrophages. Typically, cryptococcus is expelled by vomocytosis, a non-lytic expulsive mechanism also promoted by interferon (IFN)-I, or by cell lysis. However, whereas in a first phase cryptococcal vomocytosis leads to a latent asymptomatic infection confined to the lung, an enhancement in vomocytosis, promoted by IFN-I overproduction, can be deleterious, leading the fungus to reach the blood stream and invade the CNS. Cryptococcus may not be easy to diagnose in older individuals and, if not timely treated, could be potentially lethal. Therefore, this review aims to elucidate the putative causes of the increased incidence of cryptococcal CNS infection in older people discussing in depth the mechanisms of immunosenscence potentially able to predispose to neurocryptococcosis, laying the foundations for future research. A deepest understanding of this relationship could provide new ways to improve the prevention and recognition of neurocryptococcosis in aged frail people, in order to quickly manage pharmacological interventions and to adopt further preventive measures able to reduce the main risk factors.


Assuntos
Criptococose , Imunidade Inata , Imunossenescência , Humanos , Imunossenescência/imunologia , Criptococose/imunologia , Cryptococcus neoformans/imunologia , Animais , Cryptococcus gattii/imunologia , Idoso , Suscetibilidade a Doenças/imunologia
9.
J Med Primatol ; 53(5): e12733, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39245886

RESUMO

An adult female rhesus macaque presented during routine annual physical examination for evaluation of a 2.5-cm diameter superficial ulcerated dermal lesion that was subsequently diagnosed as a systemic fungal infection caused by Cryptococcus gattii. Cryptococcus gattii is one of several basidiomycetic yeasts responsible for pulmonary, neurologic, and disseminated infections in humans and animals. This report describes the diagnosis, management, and clinical resolution of a C. gattii infection in an immunocompetent 5-year-old female rhesus macaque.


Assuntos
Antifúngicos , Criptococose , Cryptococcus gattii , Macaca mulatta , Doenças dos Macacos , Animais , Cryptococcus gattii/isolamento & purificação , Criptococose/veterinária , Criptococose/tratamento farmacológico , Criptococose/diagnóstico , Criptococose/microbiologia , Feminino , Doenças dos Macacos/microbiologia , Doenças dos Macacos/diagnóstico , Doenças dos Macacos/tratamento farmacológico , Antifúngicos/uso terapêutico , Imunocompetência
10.
BMC Infect Dis ; 24(1): 1018, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304813

RESUMO

BACKGROUND: Cryptococcosis is progressively acknowledged among people, irrespective of the human with or without immunodeficiency virus (HIV). This change in epidemiology has been recorded in recent years, prompting closer examination and a broader understanding of the disease manifestations and risk factors. METHODS: The data of cryptococcal infections in China during 11 years were retrospectively analyzed. According to the position of infection, the patients were categorized into the pulmonary infection group and extrapulmonary infection group. The composition of the two groups was compared, and the potential risk factors of disseminated infection were analyzed. Logistic regression was used to analyze the prognostic risk factors of the disease. RESULTS: A total of 165 patients were enrolled. 113 (68.5%) were male, and the age was 47.49 (18-82) years. 101 cases (61.2%) had a normal immune function and 64 cases (38.8%) had impaired immune function. 45 patients had extrapulmonary infection, involving the central nervous system, bone and joint, skin and bloodstream, and 120 patients had simple pulmonary infection. The mortality of the extrapulmonary infection group (48.9%) was significantly higher than that of the pulmonary infection group (0.8%). According to univariate logistic regression analysis, immune status (hazard ratio [HR], 4.476; 95% confidence interval [CI], 1.725-11.618; P = 0.002), infection position ([HR], 113.826; [CI], 14.607-886.967; P < 0.001), white blood cell count, ([HR],1.209;[CI], 1.054-1.386; P = 0.007), hemoglobin ([HR], 0.970; [CI], 0.955-0.986; P < 0.001), platelet count ([HR], 0.993; [CI], 0.987-0.999; P = 0.026), neutrophil percentage ([HR], 1.115; [CI], 1.065-1.168; P < 0.001), lymphocyte percentage ([HR], 0.875; [CI], 0.827-0.927; P < 0.001), neutrophil-to-lymphocyte Ratio (NLR) ([HR], 1.144; [CI], 1.072-1.221; P < 0.001), monocyte percentage ([HR], 0.752; [CI], 0.618-0.915; P = 0.004) were related to the prognosis. Multivariate logistic regression analysis showed that the infection position was remained related to the prognosis with statistical significance ([HR], 0.018; [CI], 0.001-0.384; P = 0.001). CONCLUSION: Extrapulmonary infection of Cryptococcosis is an important risk factor for prognosis. High levels of neutrophils and NLR, and low levels of lymphocytes and monocytes may lead to disseminated infection of Cryptococcosis. Further studies are needed to reduce the occurrence rate of extrapulmonary infection and mortality.


Assuntos
Criptococose , Pneumopatias Fúngicas , Humanos , Criptococose/epidemiologia , Criptococose/mortalidade , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Idoso , Prognóstico , Adolescente , Estudos Retrospectivos , Adulto Jovem , China/epidemiologia , Idoso de 80 Anos ou mais , Fatores de Risco , Pneumopatias Fúngicas/epidemiologia , Pneumopatias Fúngicas/mortalidade , Pneumopatias Fúngicas/microbiologia
11.
J Neuroinflammation ; 21(1): 242, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334365

RESUMO

Cryptococcus neoformans (Cn) is an opportunistic encapsulated fungal pathogen that causes life-threatening meningoencephalitis in immunosuppressed individuals. Since IL-6 is important for blood-brain barrier support and its deficiency has been shown to facilitate Cn brain invasion, we investigated the impact of IL-6 on systemic Cn infection in vivo, focusing on central nervous system (CNS) colonization and glial responses, specifically microglia and astrocytes. IL-6 knock-out (IL-6-/-) mice showed faster mortality than C57BL/6 (Wild-type) and IL-6-/- supplemented with recombinant IL-6 (rIL-6; 40 pg/g/day) mice. Despite showing early lung inflammation but no major histological differences in pulmonary cryptococcosis progression among the experimental groups, IL-6-/- mice had significantly higher blood and brain tissue fungal burden at 7-days post infection. Exposure of cryptococci to rIL-6 in vitro increased capsule growth. In addition, IL-6-/- brains were characterized by an increased dystrophic microglia number during Cn infection, which are associated with neurodegeneration and senescence. In contrast, the brains of IL-6-producing or -supplemented mice displayed high numbers of activated and phagocytic microglia, which are related to a stronger anti-cryptococcal response or tissue repair. Likewise, culture of rIL-6 with microglia-like cells promoted high fungal phagocytosis and killing, whereas IL-6 silencing in microglia decreased fungal phagocytosis. Lastly, astrogliosis was high and moderate in infected brains removed from Wild-type and IL-6-/- supplemented with rIL-6 animals, respectively, while minimal astrogliosis was observed in IL-6-/- tissue, highlighting the potential of astrocytes in containing and combating cryptococcal infection. Our findings suggest a critical role for IL-6 in Cn CNS dissemination, neurocryptococcosis development, and host defense.


Assuntos
Criptococose , Cryptococcus neoformans , Interleucina-6 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuroglia , Animais , Camundongos , Interleucina-6/metabolismo , Neuroglia/patologia , Neuroglia/metabolismo , Neuroglia/microbiologia , Criptococose/patologia , Criptococose/imunologia , Criptococose/microbiologia , Encéfalo/patologia , Encéfalo/metabolismo
12.
Int Immunopharmacol ; 142(Pt B): 113259, 2024 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-39332096

RESUMO

Cryptococcosis, caused by infections with C. neoformans and C. gattii, presents a serious threat to global health and necessitates effective treatment strategies. Granulocyte-Macrophage Colony-Stimulating Factor, GM-CSF, is an immune-modulating cytokine that has been utilized clinically to improve host defense against infection; however, the impact of GM-CSF treatment in C. gattii infection has not been elucidated. Our current study aimed to investigate the effect of GM-CSF treatment on pulmonary immune response during C. gattii infection. In response to C. gattii infection, GM-CSF-expressing T helper cells and CD11b+ myeloid were enhanced in the lungs. The intranasal administration of GM-CSF during C. gattii infection significantly reduced pulmonary cryptococcal load, promoted an increase in pulmonary Th17 cells, as well as neutrophil infiltration in the lungs. Exposure of neutrophils to C. gattii in the presence of GM-CSF resulted in an increased neutrophil phagocytosis and fungal killing capacity, generation of reactive oxygen species (ROS), and upregulation of inflammatory cytokines and anti-microbial peptides. Although GM-CSF treatment in C. neoformans-infected mice had a comparable impact on the reduction of lung fungal burden, it resulted in the enhancement of Th1-type cytokine IFN-γ and the activation of M1 macrophages. Altogether, this study demonstrated that the intranasal delivery of GM-CSF has distinct effects on promoting the protection against C. gattii and C. neoformans by activating neutrophil/type-17 immune response and stimulating M1 macrophage/type-1 immunity, respectively.


Assuntos
Administração Intranasal , Criptococose , Cryptococcus gattii , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Pulmão , Animais , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Cryptococcus gattii/efeitos dos fármacos , Criptococose/tratamento farmacológico , Criptococose/imunologia , Pulmão/imunologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Feminino , Neutrófilos/imunologia , Neutrófilos/efeitos dos fármacos , Citocinas/metabolismo , Células Th17/imunologia , Células Th17/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Humanos
13.
Nat Microbiol ; 9(10): 2684-2695, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39232204

RESUMO

Cryptococcus neoformans is a ubiquitous soil fungus and airborne pathogen that causes over 180,000 deaths each year. Cryptococcus must adapt to host CO2 levels to cause disease, but the genetic basis for this adaptation is unknown. We utilized quantitative trait loci mapping with 374 progeny from a cross between a CO2-tolerant clinical isolate and a CO2-sensitive environmental isolate to identify genetic regions regulating CO2 tolerance. To identify specific quantitative trait genes, we applied fine mapping through bulk segregant analysis of near-isogenic progeny with distinct tolerance levels to CO2. We found that virulence among near-isogenic strains in a murine model of cryptococcosis correlated with CO2 tolerance. Moreover, we discovered that sensitive strains may adapt in vivo to become more CO2 tolerant and more virulent. These findings highlight the underappreciated role of CO2 tolerance and its importance in the ability of an opportunistic environmental pathogen to cause disease.


Assuntos
Dióxido de Carbono , Criptococose , Cryptococcus neoformans , Locos de Características Quantitativas , Cryptococcus neoformans/genética , Cryptococcus neoformans/patogenicidade , Virulência/genética , Animais , Dióxido de Carbono/metabolismo , Criptococose/microbiologia , Camundongos , Modelos Animais de Doenças , Mapeamento Cromossômico , Humanos , Adaptação Fisiológica/genética , Genes Fúngicos , Feminino
14.
BMC Pulm Med ; 24(1): 441, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251951

RESUMO

BACKGROUND: To explore the associations of computed tomography (CT) image features with the serum cryptococcal antigen (CrAg) titers measured by the lateral flow assay (LFA) in localized pulmonary cryptococcosis patients. METHODS: A retrospective analysis of patients with pathologically confirmed pulmonary cryptococcosis admitted to the First Affiliated Hospital of Xiamen University from January 2016 to December 2022 was performed. Clinical data, CT results, serum CrAg-LFA test results, and follow-up data were collected and analyzed. RESULTS: A total of 107 patients with localized pulmonary cryptococcosis were included, of which 31 had a single lesion in chest CT and the other 76 had multiple lesions. The positivity rate was (94.74% vs 64.52%) and titers of serum CrAg-LFA (1.77 ± 0.87 vs 0.91 ± 0.98) in the multiple lesion group were higher than those in the single lesion group, respectively. Multivariate linear regression analysis showed that the serum CrAg titers were positively associated with the number of lesions (ß, 0.08; 95% CI, 0.05 to 0.12) and the lesion size (ß, 0.40; 95% CI, 0.31 to 0.50) after adjusting other covariates. The serum CrAg-LFA titers of 60 pulmonary cryptococcosis patients showed a decreasing trend with the reduction in pulmonary lesion size after effective therapy. CONCLUSION: In pulmonary cryptococcosis patients, the number and size of lung lesions are positively correlated with the titers of the serum CrAg-LFA test. The CrAg-LFA test could be a useful tool for the diagnosis, severity assessment, and therapeutic monitoring of localized pulmonary cryptococcosis patients.


Assuntos
Antígenos de Fungos , Criptococose , Pneumopatias Fúngicas , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Antígenos de Fungos/sangue , Criptococose/diagnóstico por imagem , Criptococose/sangue , Pneumopatias Fúngicas/diagnóstico por imagem , Pneumopatias Fúngicas/sangue , Pneumopatias Fúngicas/imunologia , Adulto , Idoso , Pulmão/diagnóstico por imagem , Pulmão/patologia
15.
Front Cell Infect Microbiol ; 14: 1448229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39193507

RESUMO

The basidiomycete fungus Cryptococcus neoformans is a useful model for investigating mechanisms of fungal pathogenesis in mammalian hosts. This pathogen is the causative agent of cryptococcal meningitis in immunocompromised patients and is in the critical priority group of the World Health Organization fungal priority pathogens list. In this study, we employed a mutant lacking the OPI3 gene encoding a methylene-fatty-acyl-phospholipid synthase to characterize the role of phosphatidylcholine (PC) and lipid homeostasis in the virulence of C. neoformans. We first confirmed that OPI3 was required for growth in nutrient limiting conditions, a phenotype that could be rescued with exogenous choline and PC. Additionally, we established that loss of Opi3 and the lack of PC lead to an accumulation of neutral lipids in lipid droplets and alterations in major lipid classes. The growth defect of the opi3Δ mutant was also rescued by sorbitol and polyethylene glycol (PEG), a result consistent with protection of ER function from the stress caused by lipid imbalance. We then examined the impact of Opi3 on virulence and found that the dependence of PC synthesis on Opi3 caused reduced capsule size and this was accompanied by an increase in shed capsule polysaccharide and changes in cell wall composition. Further tests of virulence demonstrated that survival in alveolar macrophages and the ability to cause disease in mice were not impacted by loss of Opi3 despite the choline auxotrophy of the mutant in vitro. Overall, this work establishes the contribution of lipid balance to virulence factor elaboration by C. neoformans and suggests that host choline is sufficient to support proliferation during disease.


Assuntos
Criptococose , Cryptococcus neoformans , Modelos Animais de Doenças , Cryptococcus neoformans/patogenicidade , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , Cryptococcus neoformans/crescimento & desenvolvimento , Animais , Virulência , Criptococose/microbiologia , Camundongos , Metabolismo dos Lipídeos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fosfatidilcolinas/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Cápsulas Fúngicas/metabolismo , Cápsulas Fúngicas/genética , Parede Celular/metabolismo , Colina/metabolismo , Feminino , Gotículas Lipídicas/metabolismo
16.
Front Cell Infect Microbiol ; 14: 1407807, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39206044

RESUMO

Background: Cryptococcosis is an invasive infection that commonly affects immunosuppressed individuals, especially patients with HIV infection. Cryptococcal infection in HIV-infected patients should be considered a major health concern because it is associated with high morbidity and mortality rates. In this study, we aimed to evaluate the clinical characteristics and prognostic factors of cryptococcal infections in human immunodeficiency virus (HIV)-infected patients to facilitate effective clinical management and improve patient outcomes. Methods: We reviewed and analyzed the clinical data and relevant laboratory test results of HIV-infected patients with positive cryptococcal cultures and reserved strains between 2013 and 2023 from Beijing Youan Hospital affiliated to Capital Medical University. The clinical characteristics and laboratory test results of the patients were compared, and the correlation between parameters and the prognoses of the patients at different observation timepoints (3, 6, 9, and 12 months) was analyzed. Results: A total of 76 patients (70 males and six females; median age, 37 years) were included in this study. The results indicated that the later the initiation of antiretroviral therapy (ART) after the diagnosis of HIV infection (> 6 months), the higher the probability of death. Analysis of the correlation between the time of ART initiation and the timing of treatment for cryptococcal infections showed that the time of ART initiation was strongly related to survival at different timepoints. Initiation of ART time within 0-4 weeks, 4-6 weeks and more than 6weeks of starting treatment for Cryptococcus infection was associated with a lower mortality rate at 12-month, the 3-month, 6- and 9-month follow-up timepoint separately. Conclusions: Although cryptococcal infection in HIV-infected patients continues to be a challenging and intricate issue, ART is a key factor that affects its prognosis. The later ART is started, the worse the prognosis of the infection. The time of ART initiation and the timing of treatment for cryptococcal infections should be further refined and balanced based on different clinical courses. Thus, clinicians should pay closer attention to cryptococcal infections in patients with HIV infection and initiate ART based on the patient's clinical condition.


Assuntos
Criptococose , Infecções por HIV , Humanos , Feminino , Masculino , Adulto , Infecções por HIV/complicações , Prognóstico , Criptococose/mortalidade , Criptococose/tratamento farmacológico , Criptococose/complicações , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Antifúngicos/uso terapêutico , Cryptococcus/isolamento & purificação , Hospitais , China/epidemiologia
17.
mBio ; 15(9): e0184724, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39136442

RESUMO

Cryptococcus neoformans (Cn) is an opportunistic fungal microorganism that causes life-threatening meningoencephalitis. During the infection, the microbial population is heterogeneously composed of cells with varying generational ages, with older cells accumulating during chronic infections. This is attributed to their enhanced resistance to phagocytic killing and tolerance of antifungals like fluconazole (FLC). In this study, we investigated the role of ergosterol synthesis, ATP-binding cassette (ABC) transporters, and mitochondrial metabolism in the regulation of age-dependent FLC tolerance. We find that old Cn cells increase the production of ergosterol and exhibit upregulation of ABC transporters. Old cells also show transcriptional and phenotypic characteristics consistent with increased metabolic activity, leading to increased ATP production. This is accompanied by increased production of reactive oxygen species, which results in mitochondrial fragmentation. This study demonstrates that the metabolic changes occurring in the mitochondria of old cells drive the increase in ergosterol synthesis and the upregulation of ABC transporters, leading to FLC tolerance. IMPORTANCE: Infections caused by Cryptococcus neoformans cause more than 180,000 deaths annually. Estimated 1-year mortality for patients receiving care ranges from 20% in developed countries to 70% in developing countries, suggesting that current treatments are inadequate. Some fungal cells can persist and replicate despite the usage of current antifungal regimens, leading to death or treatment failure. Aging in fungi is associated with enhanced tolerance against antifungals and resistance to killing by host cells. This study shows that age-dependent increase in mitochondrial reactive oxygen species drive changes in the regulation of membrane transporters and ergosterol synthesis, ultimately leading to the heightened tolerance against fluconazole in old C. neoformans cells. Understanding the underlying molecular mechanisms of this age-associated antifungal tolerance will enable more targeted antifungal therapies for cryptococcal infections.


Assuntos
Antifúngicos , Cryptococcus neoformans , Farmacorresistência Fúngica , Fluconazol , Mitocôndrias , Espécies Reativas de Oxigênio , Cryptococcus neoformans/efeitos dos fármacos , Fluconazol/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Antifúngicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Ergosterol/metabolismo , Criptococose/microbiologia , Criptococose/imunologia , Testes de Sensibilidade Microbiana , Humanos , Regulação Fúngica da Expressão Gênica
18.
JBJS Case Connect ; 14(3)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39208152

RESUMO

CASE: A 38-year-old woman presented to our clinic with right knee pain and difficulty ambulating. After cultures were obtained, a cryptococcal infection of the patella was identified. Subsequent workup revealed previously undiagnosed HIV/AIDS and a disseminated cryptococcal infection. CONCLUSION: Over a 20-month course, the patient was treated with fluconazole and antiretroviral therapy with very limited medication compliance. The disseminated infection caused cutaneous, hepatic, and cerebral complications. Eventually, compliance improved, and a final procedure to obtain post-treatment cultures and apply antifungal bone matrix was completed. The patient cleared the infection and will likely require lifetime antifungal treatment.


Assuntos
Criptococose , Osteomielite , Patela , Humanos , Feminino , Adulto , Criptococose/tratamento farmacológico , Criptococose/diagnóstico por imagem , Patela/diagnóstico por imagem , Patela/microbiologia , Osteomielite/microbiologia , Osteomielite/diagnóstico por imagem , Osteomielite/tratamento farmacológico , Antifúngicos/uso terapêutico , Fluconazol/uso terapêutico
19.
Hell J Nucl Med ; 27(2): 149-153, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39097809

RESUMO

OBJECTIVE: Cryptococcus, a genus of fungi, primarily includes Cryptococcus neoformans and Cryptococcus gattii, both known to cause human infections. Skeletal infections are rare, and there have been no reported cases of bone cryptococcal infection in conjunction with differentiated thyroid carcinoma. SUBJECT AND METHODS: A 56-year-old female presented with a one-month history of "cough and throat irritation." Chest CT revealed scattered small nodules in both lungs,suggestive of metastasis.There was minimal inflammation in both lungs, and scattered lymph nodes were observed in the mediastinum and upper pulmonary hilum. RESULTS: The patient was diagnosed with differentiated thyroid carcinoma complicated by cryptococcal infection. Antifungal treatment with itraconazole 200mg/day was initiated, and after 3 months, clinical symptoms disappeared, with a reduction in lung nodules observed in follow-up chest CT. CONCLUSION: When diagnosing distant metastasis in differentiated thyroid carcinoma, a comprehensive analysis combining imaging studies and serum thyroid globulin plays a complementary role, as illustrated in this case of differentiated thyroid carcinoma concurrent with cryptococcal infection.


Assuntos
Criptococose , Neoplasias da Glândula Tireoide , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Criptococose/diagnóstico por imagem , Criptococose/complicações , Inflamação/diagnóstico por imagem , Inflamação/complicações , Granuloma/diagnóstico por imagem , Granuloma/complicações , Tomografia Computadorizada por Raios X
20.
PLoS One ; 19(8): e0308216, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39088434

RESUMO

Cryptococcosis is a fungal infection that is becoming increasingly prevalent worldwide, particularly among individuals with compromised immune systems, such as HIV patients. Amphotericin B (AmB) is the first-line treatment mainly combined with flucytosine. The scarcity and the prohibitive cost of this regimen urge the use of fluconazole as an alternative, leading to increased rates of treatment failure and relapses. Therefore, there is a critical need for efficient and cost-effective therapy to enhance the efficacy of AmB. In this study, we evaluated the efficacy of the HIV protease inhibitors (PIs) to synergize the activity of AmB in the treatment of cryptococcosis. Five PIs (ritonavir, atazanavir, saquinavir, lopinavir, and nelfinavir) were found to synergistically potentiate the killing activity of AmB against Cryptococcus strains with Æ©FICI ranging between 0.09 and 0.5 against 20 clinical isolates. This synergistic activity was further confirmed in a time-kill assay, where different AmB/PIs combinations exhibited fungicidal activity within 24 hrs. Additionally, PIs in combination with AmB exhibited an extended post-antifungal effect on treated cryptococcal cells for approximately 10 hrs compared to 4 hours with AmB alone. This promising activity against cryptococcal cells did not exhibit increased cytotoxicity towards treated kidney cells, ruling out the risk of drug combination-induced nephrotoxicity. Finally, we evaluated the efficacy of AmB/PIs combinations in the Caenorhabditis elegans model of cryptococcosis, where these combinations significantly reduced the fungal burden of the treated nematodes by approximately 2.44 Log10 CFU (92.4%) compared to the untreated worms and 1.40 Log10 ((39.4%) compared to AmB alone. The cost-effectiveness and accessibility of PIs in resource-limited geographical areas compared to other antifungal agents, such as flucytosine, make them an appealing choice for combination therapy.


Assuntos
Anfotericina B , Antifúngicos , Criptococose , Sinergismo Farmacológico , Inibidores da Protease de HIV , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Inibidores da Protease de HIV/uso terapêutico , Inibidores da Protease de HIV/farmacologia , Animais , Criptococose/tratamento farmacológico , Humanos , Caenorhabditis elegans/microbiologia , Caenorhabditis elegans/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Cryptococcus neoformans/efeitos dos fármacos , Quimioterapia Combinada , Ritonavir/uso terapêutico , Ritonavir/farmacologia , Cryptococcus/efeitos dos fármacos
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