Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 189
Filter
Add more filters

Publication year range
1.
BMC Neurol ; 20(1): 297, 2020 Aug 12.
Article in English | MEDLINE | ID: mdl-32787794

ABSTRACT

BACKGROUND: Cerebral cryptococcomas is a rare form of central nervous system cryptococcosis. Most previous cases were mistaken for neoplasm before surgery. We present a case of cerebral cryptococcomas whose radiological profiles resembled demyelinating disease, especially tumefactive demyelinating lesion. CASE PRESENTATION: A 40-year-old male was admitted for 1-week-long unconsciousness. Brain MRI revealed a rim-enhanced mass within the corpus callosum body. Central nervous system demyelinating disease was suspected. Empirical corticosteroid treatment led to some improvement, but his condition deteriorated 2 months later. Brain MRI revealed punctate new foci. Cryptococcus neoformans was detected in cerebrospinal fluid. Cryptococcus antigen test was positive in his current and previous cerebrospinal fluid samples. The patient died despite standard antifungal treatment. CONCLUSION: Diagnosis of cerebral cryptococcomas is challenging. It may mimic demyelinating diseases.


Subject(s)
Central Nervous System Bacterial Infections/diagnosis , Cryptococcosis/diagnosis , Demyelinating Diseases/diagnosis , Adult , Antigens, Fungal/cerebrospinal fluid , Central Nervous System Bacterial Infections/cerebrospinal fluid , Cryptococcosis/cerebrospinal fluid , Cryptococcus neoformans/isolation & purification , Diagnosis, Differential , Humans , Magnetic Resonance Imaging , Male , Neuroimaging
2.
Mycopathologia ; 185(3): 503-514, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32440853

ABSTRACT

The basidiomycete yeast Cryptococcus neoformans causes disease in immunocompromized patients. Whole genome sequencing (WGS) technology provides insights into the molecular epidemiology of C. neoformans. However, the number of such studies is limited. Here we used WGS and multilocus sequence typing (MLST) to determine the genetic diversity of C. neoformans isolates and genetic structures of their populations among patients admitted to a single hospital in Bangkok, Thailand. Seven isolates from six patients collected during 1 year were identified as C. neoformans sensu stricto according to colony morphology, microscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and nucleotide sequence analysis of internal transcribed sequences. These isolates were sensitive to the antifungal drugs amphotericin B, fluconazole, 5-flucytosine, voriconazole, itraconazole and posaconazole and were mating type α and molecular type VNI. MLST analysis identified ST4, ST5 and ST6. We further employed WGS to determine the genetic diversity and relationships of C. neoformans isolated here combined with C. neoformans sequences data acquired from a public database (n = 42). We used the data to construct a phylogenetic tree. WGS provided additional genomics data and achieved high discriminatory power for identifying C. neoformans isolates isolated in Thailand. This report further demonstrates the applicability of WGS analysis for conducting molecular epidemiology and provides insight into the genetic diversity of C. neoformans isolates from one hospital in Thailand.


Subject(s)
Cryptococcosis/microbiology , Cryptococcus neoformans/classification , Genetic Variation , Antifungal Agents/pharmacology , Cryptococcosis/blood , Cryptococcosis/cerebrospinal fluid , Cryptococcus neoformans/drug effects , Cryptococcus neoformans/genetics , Cryptococcus neoformans/isolation & purification , Genotype , Humans , Multilocus Sequence Typing , Thailand , Whole Genome Sequencing
3.
Infection ; 47(4): 565-570, 2019 Aug.
Article in English | MEDLINE | ID: mdl-30725316

ABSTRACT

PURPOSE: Fungal central nervous system (CNS) infections show a high mortality rate and only a few antifungal agents are available to treat these infections. We hypothesize that the different biochemical properties of human cerebrospinal fluid (CSF) compared to the standard growth medium lead to the altered activity of antifungal agents in CSF. We investigated the in vitro activity of two of these agents, i.e., amphotericin B (AmB) and voriconazole (VOR), against three different fungi in CSF in comparison to sabouraud-dextrose broth (SDB). METHODS: CSF samples from patients who did not receive any antibiotics were collected. Time-kill curves were performed in CSF and SDB using static antibiotic concentrations of AmB and VOR against ATCC strains of Candida albicans, Candida krusei, and Cryptococcus neoformans. RESULTS: In our experiments, both AmB and VOR showed superior activity in SDB compared to CSF. Nevertheless, AmB achieved fungicidal activity in CSF after 24 h against all test strains. Voriconazole only achieved fungistatic activity against C. albicans and C. neoformans in CSF. CONCLUSIONS: In summary, our data demonstrate that growth of fungal pathogens but even more importantly activity of antifungal agents against Candida and Cryptococcus species can differ significantly in CSF compared to the standard growth medium. Both findings should be taken into consideration when applying PK/PD simulations to fungal infections of the CNS.


Subject(s)
Amphotericin B/pharmacology , Antifungal Agents/pharmacology , Candida/drug effects , Cerebrospinal Fluid/microbiology , Cryptococcus neoformans/drug effects , Voriconazole/pharmacology , Candida albicans/drug effects , Candidiasis/cerebrospinal fluid , Central Nervous System Infections/cerebrospinal fluid , Cryptococcosis/cerebrospinal fluid , Humans
4.
BMC Infect Dis ; 19(1): 108, 2019 Feb 04.
Article in English | MEDLINE | ID: mdl-30717679

ABSTRACT

BACKGROUND: For definitive diagnosis of cryptococcal meningitis, Cryptococcus neoformans and/or C. gattii must be identified within cerebral spinal fluid from the patients. The traditional methods for detecting Cryptococcus spp. such as India ink staining and culture are not ideal. Although sensitive and specific enough, detection of cryptococcal antigen polysaccharide has a high dose hook effect. Therefore, the aim of this study was to introduce a new rapid and simple detection method of Cryptococcus neoformans and C. gattii in cerebral spinal fluid. METHODS: The lateral flow strips combined with recombinase polymerase amplification (LF-RPA) assay was constructed to detect the specific DNA sequences of C. neoformans and C. gattii. The detection limit was evaluated using serial dilutions of C. neoformans and C. gattii genomic DNA. The specificity was assessed by excessive amount of other pathogens genomic DNA. The optimal detection time and amplification temperature were also analyzed. The diagnostic parameters were first calculated using 114 clinical specimens and then compared with that of other diagnostic method. A brief analysis and comparison of different DNA extraction methods was discussed, too. RESULTS: The LF-RPA assay could detect 0.64 pg of genomic DNA of C. neoformans per reaction within 10 min and was highly specific for Cryptococcus spp.. The system could work well at a wide range of temperature from 25 to 45 °C. The overall sensitivity and specificity were 95.2 and 95.8% respectively. As amplification template for LF-RPA assay, both cell lysates and genomic DNA produce similar experimental results. CONCLUSIONS: The LF-RPA system described here is shown to be a sensitive and specific method for the visible, rapid, and accurate detection of Cryptococcus spp. in cerebral spinal fluid and might be useful for clinical preliminary screening of cryptococcal meningitis.


Subject(s)
Cryptococcosis/diagnosis , Cryptococcus gattii/isolation & purification , Cryptococcus neoformans/isolation & purification , Meningitis, Cryptococcal/diagnosis , Polymerase Chain Reaction/methods , RNA, Fungal/cerebrospinal fluid , Antigens, Fungal/cerebrospinal fluid , Antigens, Fungal/genetics , Cryptococcosis/cerebrospinal fluid , Cryptococcus gattii/genetics , Cryptococcus neoformans/genetics , DNA Primers/genetics , Early Diagnosis , Humans , Limit of Detection , Meningitis, Cryptococcal/cerebrospinal fluid , Microfluidic Analytical Techniques/methods , RNA, Fungal/analysis , Recombinases/genetics , Sensitivity and Specificity , Temperature
5.
Clin Infect Dis ; 65(9): 1551-1559, 2017 Oct 16.
Article in English | MEDLINE | ID: mdl-29048509

ABSTRACT

BACKGROUND: Patients with human immunodeficiency virus/AIDS-associated cryptococcal meningitis (CM) frequently experience clinical deterioration, known as cryptococcosis-associated immune reconstitution inflammatory syndrome (C-IRIS), upon initiation of antiretroviral therapy (ART). The immunological mechanisms underlying C-IRIS are incompletely defined and no reliable predictive biomarkers exist. We investigated whether plasma or cerebrospinal fluid (CSF) levels of cytokines and chemokines predicted C-IRIS and are potential predictive biomarkers. METHODS: Patients with CM who experienced C-IRIS (N = 27) upon ART initiation were compared to CD4+ T-cell count-matched patients without C-IRIS (N = 27). Plasma and CSF collected pre-ART were assayed for cytokines and chemokines using a 17-plex Luminex kit or enzyme-linked immunosorbent assay. Cox proportional hazards regression and principal component analyses were also performed. RESULTS: Plasma interleukin (IL) 2, IL-4, IL-5, IL-7, IL-17, interferon-γ, and tumor necrosis factor-α levels were higher in C-IRIS patients compared to controls (all P < .05), with IL-5 and IL-7 significant after Bonferroni-Holm correction. In multivariate Cox proportional hazards regression, high IL-5 (hazard ratio [HR], 5.76 [95% confidence interval {CI}, .77-43.0]; P = .088) and IL-7 (HR, 9.30 [95% CI, 1.96-44.0]; P = .005) were predictive of C-IRIS. Plasma IL-5 (P = .0008) and IL-10 (P = .0089) were lower in those who achieved CSF cryptococcal culture negativity compared to those with positive cultures pre-ART. There were no significant differences in CSF cytokine or chemokine levels between cases and controls. CONCLUSIONS: High plasma IL-5 and IL-7 levels pre-ART were associated with increased risk of developing C-IRIS. High IL-5 levels may reflect a Th2 environment associated with impaired clearance of cryptococci while high IL-7 levels may reflect IL-7/IL-7R pathway dysfunction in T cells, both of which could be associated with C-IRIS immunopathogenesis.


Subject(s)
AIDS-Related Opportunistic Infections/blood , Cryptococcosis/blood , Immune Reconstitution Inflammatory Syndrome/blood , Interleukin-5/blood , Interleukin-7/blood , AIDS-Related Opportunistic Infections/cerebrospinal fluid , AIDS-Related Opportunistic Infections/epidemiology , Adult , Anti-Retroviral Agents/administration & dosage , Anti-Retroviral Agents/therapeutic use , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/epidemiology , Female , HIV Infections/drug therapy , HIV Infections/epidemiology , Humans , Immune Reconstitution Inflammatory Syndrome/cerebrospinal fluid , Immune Reconstitution Inflammatory Syndrome/epidemiology , Interleukin-5/cerebrospinal fluid , Interleukin-7/cerebrospinal fluid , Male , Principal Component Analysis , Prospective Studies
6.
Eur J Pediatr ; 176(9): 1235-1244, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28776195

ABSTRACT

Cryptococcosis is a rare pediatric disease. The aim of the study is to describe clinical characteristics and prognosis of pediatric cryptococcosis from 2002 to 2014 in Beijing Children's Hospital. A total of 53 cases of cryptococcosis were identified, 69.8% of which were males. The mean age was 7 years. Forty-one (77.4%) patients had no underlying conditions. Fever, headache, and vomiting were the most common symptoms. The most common sites were the central nervous system (CNS), followed by the lungs. Most patients received a combination of amphotericin B and fluconazole with or without flucytosine as their initial regimen. Twenty-seven patients received a follow-up and six patients (22.2%) had died. The factors associated with neurological complications or death were headache (P = 0.008), seizures (P = 0.006), visual impairment (P = 0.011), neck stiffness (P = 0.008), low erythrocyte sedimentation rate (ESR) (P = 0.024), and a cerebral spinal fluid (CSF) cryptococcal antigen titer ≥ 1:1024 (P = 0.038). CONCLUSIONS: The majority of cryptococcosis cases in China occurred in children without underlying conditions, causing multiple organ damage. The CNS was the most common site. Patients who had headaches, seizures, or high CSF antigen titers experienced neurological complications or died. What is known: • Cryptococcosis is a rare cause of infection in children. What is new: • This review gives a brief overview over pediatric cryptococcosis in China.


Subject(s)
Antifungal Agents/therapeutic use , Central Nervous System Fungal Infections/microbiology , Cryptococcosis , Lung Diseases, Fungal/microbiology , Adolescent , Central Nervous System Fungal Infections/drug therapy , Central Nervous System Fungal Infections/epidemiology , Child , Child, Preschool , China , Cryptococcosis/blood , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/diagnosis , Cryptococcosis/drug therapy , Cryptococcus neoformans/isolation & purification , Female , Headache/etiology , Humans , Infant , Lung Diseases, Fungal/drug therapy , Lung Diseases, Fungal/epidemiology , Magnetic Resonance Imaging , Male , Prognosis , Retrospective Studies , Seizures/etiology , Treatment Outcome
7.
An Acad Bras Cienc ; 87(2 Suppl): 1293-309, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26247147

ABSTRACT

Brain infection by the fungus Cryptococcus neoformans results in an estimated 500,000 human deaths per annum. Colonization of the central nervous system (CNS) by C. neoformans causes different clinical syndromes that involve interaction of a number of fungal components with distinct brain cells. In this manuscript, our literature review confirmed the notion that the Cryptococcus field is expanding rapidly, but also suggested that studies on neuropathogenesis still represent a small fraction of basic research activity in the field. We therefore discussed anatomical and physiological aspects of the brain during infection by C. neoformans, in addition to mechanisms by which brain resident cells interact with the fungus. This review suggests that multiple efforts are necessary to improve the knowledge on how C. neoformans affects brain cells, in order to enable the generation of new therapeutic tools in a near future.


Subject(s)
Brain Diseases/microbiology , Cryptococcosis/microbiology , Cryptococcosis/pathology , Cryptococcus neoformans , Animals , Brain Diseases/cerebrospinal fluid , Brain Diseases/pathology , Brain Diseases/physiopathology , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/physiopathology , Disease Models, Animal , Humans
8.
Clin Infect Dis ; 58(12): 1771-7, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24668125

ABSTRACT

BACKGROUND: Knowledge of central nervous system (CNS) opportunistic infections (OIs) among people living with human immunodeficiency virus (HIV) in sub-Saharan Africa is limited. METHODS: We analyzed 1 cerebrospinal fluid (CSF) sample from each of 331 HIV-infected adults with symptoms suggestive of CNS OI at a tertiary care center in Zambia. We used pathogen-specific primers to detect DNA from JC virus (JCV), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV) types 1 and 2, Mycobacterium tuberculosis, and Toxoplasma gondii via real-time polymerase chain reaction (PCR). RESULTS: The patients' median CD4(+) T-cell count was 89 cells/µL (interquartile range, 38-191 cells/µL). Of 331 CSF samples, 189 (57.1%) had at least 1 pathogen. PCR detected DNA from EBV in 91 (27.5%) patients, M. tuberculosis in 48 (14.5%), JCV in 20 (6.0%), CMV in 20 (6.0%), VZV in 13 (3.9%), HSV-1 in 5 (1.5%), and HSV-2 and T. gondii in none. Fungal and bacteriological studies showed Cryptococcus in 64 (19.5%) patients, pneumococcus in 8 (2.4%), and meningococcus in 2 (0.6%). Multiple pathogens were found in 68 of 189 (36.0%) samples. One hundred seventeen of 331 (35.3%) inpatients died during their hospitalization. Men were older than women (median, 37 vs 34 years; P = .01), more recently diagnosed with HIV (median, 30 vs 63 days; P = .03), and tended to have a higher mortality rate (40.2% vs 30.2%; P = .07). CONCLUSIONS: CNS OIs are frequent, potentially treatable complications of AIDS in Zambia. Multiple pathogens often coexist in CSF. EBV is the most prevalent CNS organism in isolation and in coinfection. Whether it is associated with CNS disease or a marker of inflammation requires further investigation. More comprehensive testing for CNS pathogens could improve treatment and patient outcomes in Zambia.


Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , Bacterial Infections/diagnosis , Central Nervous System Infections/diagnosis , DNA/cerebrospinal fluid , Herpesviridae/genetics , Virus Diseases/diagnosis , AIDS-Related Opportunistic Infections/cerebrospinal fluid , AIDS-Related Opportunistic Infections/mortality , Adult , Bacterial Infections/cerebrospinal fluid , Bacterial Infections/mortality , CD4 Lymphocyte Count , Central Nervous System Infections/cerebrospinal fluid , Central Nervous System Infections/mortality , Cross-Sectional Studies , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/diagnosis , Cryptococcosis/mortality , Cryptococcus/genetics , DNA, Bacterial/cerebrospinal fluid , DNA, Fungal/cerebrospinal fluid , DNA, Protozoan/cerebrospinal fluid , DNA, Viral/cerebrospinal fluid , Female , Humans , JC Virus/genetics , Male , Molecular Diagnostic Techniques , Mycobacterium tuberculosis/genetics , Neisseria meningitidis/genetics , Seizures/microbiology , Seizures/parasitology , Streptococcus pneumoniae/genetics , Toxoplasma/genetics , Toxoplasmosis/cerebrospinal fluid , Toxoplasmosis/diagnosis , Virus Diseases/cerebrospinal fluid , Virus Diseases/mortality , Zambia
9.
J Biol Chem ; 287(19): 15298-306, 2012 May 04.
Article in English | MEDLINE | ID: mdl-22418440

ABSTRACT

Cryptococcus neoformans is a pathogenic yeast that can invade the brain and cause meningoencephalitis. Our previous in vitro studies suggested that the interaction between C. neoformans hyaluronic acid and human brain endothelial CD44 could be the initial step of brain invasion. In this report, we used a CD44 knock-out (KO or CD44(-/-)) mouse model to explore the importance of CD44 in C. neoformans brain invasion. Our results showed that C. neoformans-infected CD44 KO mice survived longer than the infected wild-type mice. Consistent with our in vitro results, the brain and cerebrospinal fluid fungal burden was reduced in CD44-deficient mice. Histopathological studies showed smaller and fewer cystic lesions in the brains of CD44 KO mice. Interestingly, the cystic lesions contained C. neoformans cells embedded within their polysaccharide capsule and were surrounded by host glial cells. We also found that a secondary hyaluronic acid receptor, RHAMM (receptor of hyaluronan-mediated motility), was present in the CD44 KO mice. Importantly, our studies demonstrated an in vivo blocking effect of simvastatin. These results suggest that the CD44 and RHAMM receptors function on membrane lipid rafts during invasion and that simvastatin may have a potential therapeutic role in C. neoformans infections of the brain.


Subject(s)
Brain/metabolism , Cryptococcosis/metabolism , Cryptococcus neoformans/metabolism , Extracellular Matrix Proteins/metabolism , Hyaluronan Receptors/metabolism , Animals , Blotting, Western , Brain/drug effects , Brain/microbiology , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/microbiology , Cryptococcus neoformans/pathogenicity , Cryptococcus neoformans/physiology , Extracellular Matrix Proteins/genetics , Female , Host-Pathogen Interactions , Hyaluronan Receptors/genetics , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Mice , Mice, Inbred C57BL , Mice, Knockout , Microscopy, Fluorescence , Neuroglia/drug effects , Neuroglia/metabolism , Neuroglia/microbiology , Protein Binding , RNA Interference , Simvastatin/pharmacology , Virulence
10.
J Mycol Med ; 31(2): 101113, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33540367

ABSTRACT

INTRODUCTION: Cryptococcus gattii species complex is endemic to tropical and subtropical regions and is described as a causative agent of cryptococcosis in immunocompetent individuals. CASE PRESENTATION: We describe the first case of cryptococcosis in a HIV-negative patient from Ivory Coast infected by Cryptococcus gattii sensu stricto VGI. Isolates were recovered from cerebrospinal fluid (CSF) prior to systemic antifungal treatment up to 42 days after detection of the presence of yeasts in the CSF. Eighteen isolates were recovered, genetic diversity and antifungal susceptibility analyses were performed. All the isolates belonged to the Cryptococcus gattii sensu stricto (B;VGI) and were identified as a new sequence type (ST) 553 by Multilocus Sequence Typing (MLST) analyses. Susceptibility testing showed that all the strains had a wild-type phenotype for fluconazole, amphotericin B and flucytosine. Treatment with fluconazole (1200mg/day) was initiated with success. CONCLUSION: This is the first case report of the presence of C. gattii sensu stricto VGI in a HIV-negative ivorian patient and the second report of the presence of species from the C. gattii complex species in this country.


Subject(s)
Antifungal Agents/pharmacology , Cryptococcosis/diagnosis , Cryptococcus gattii/drug effects , Cryptococcus gattii/genetics , Genotype , Adult , Antifungal Agents/therapeutic use , Cote d'Ivoire , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/drug therapy , Cryptococcosis/microbiology , Cryptococcus gattii/classification , Cryptococcus gattii/pathogenicity , Female , Genetic Variation , HIV Infections , Humans , Microbial Sensitivity Tests
11.
mBio ; 12(6): e0231321, 2021 12 21.
Article in English | MEDLINE | ID: mdl-34724829

ABSTRACT

Cryptococcus neoformans is a major human central nervous system (CNS) fungal pathogen causing considerable morbidity and mortality. In this study, we provide the widest view to date of the yeast transcriptome directly from the human subarachnoid space and within cerebrospinal fluid (CSF). We captured yeast transcriptomes from C. neoformans of various genotypes in 31 patients with cryptococcal meningoencephalitis as well as several Cryptococcus gattii infections. Using transcriptome sequencing (RNA-seq) analyses, we compared the in vivo yeast transcriptomes to those from other environmental conditions, including in vitro growth on nutritious media or artificial CSF as well as samples collected from rabbit CSF at two time points. We ranked gene expressions and identified genetic patterns and networks across these diverse isolates that reveal an emphasis on carbon metabolism, fatty acid synthesis, transport, cell wall structure, and stress-related gene functions during growth in CSF. The most highly expressed yeast genes in human CSF included those known to be associated with survival or virulence and highlighted several genes encoding hypothetical proteins. From that group, a gene encoding the CMP1 putative glycoprotein (CNAG_06000) was selected for functional studies. This gene was found to impact the virulence of Cryptococcus in both mice and the CNS rabbit model, in agreement with a recent study also showing a role in virulence. This transcriptional analysis strategy provides a view of regulated yeast genes across genetic backgrounds important for human CNS infection and a relevant resource for the study of cryptococcal genes, pathways, and networks linked to human disease. IMPORTANCE Cryptococcus is the most common fungus causing high-morbidity and -mortality human meningitis. This encapsulated yeast has a unique propensity to travel to the central nervous system to produce disease. In this study, we captured transcriptomes of yeasts directly out of the human cerebrospinal fluid, the most concerning site of infection. By comparing the RNA transcript levels with other conditions, we gained insights into how the basic machinery involved in metabolism and environmental responses enable this fungus to cause disease at this body site. This approach was applied to clinical isolates with diverse genotypes to begin to establish a genotype-agnostic understanding of how the yeast responds to stress. Based on these results, future studies can focus on how these genes and their pathways and networks can be targeted with new therapeutics and possibly classify yeasts with bad infection outcomes.


Subject(s)
Cryptococcosis/microbiology , Cryptococcus neoformans/genetics , Meningoencephalitis/microbiology , Animals , Central Nervous System/microbiology , Cryptococcosis/cerebrospinal fluid , Cryptococcus neoformans/classification , Cryptococcus neoformans/isolation & purification , Cryptococcus neoformans/pathogenicity , Disease Models, Animal , Female , Fungal Proteins/genetics , Fungal Proteins/metabolism , Genotype , Humans , Male , Meningoencephalitis/diagnosis , Mice , RNA-Seq , Rabbits , Transcriptome , Virulence
12.
Eur J Clin Microbiol Infect Dis ; 29(5): 571-6, 2010 May.
Article in English | MEDLINE | ID: mdl-20221657

ABSTRACT

Fluorescence in situ hybridisation (FISH) is a suitable technique for the rapid, reliable and cultivation-independent identification of microbial pathogens. This study describes the development of fluorescently labelled rRNA-targeted oligonucleotides and a FISH assay to detect and identify Cryptococcus neoformans in culture and biological samples. All C. neoformans reference and clinical isolates gave positive signals with the specific oligonucleotide probes, whereas all non-target yeast species gave negative reactions with the same probes. The assay was also successfully applied to the detection of C. neoformans cells in cerebrospinal samples from patients with clinical diagnosis of cryptococcosis. The described FISH-based assay revealed to be practical, sensitive and specific for the detection and identification of C. neoformans yeasts.


Subject(s)
Cryptococcosis/microbiology , Cryptococcus neoformans/isolation & purification , DNA Probes/chemistry , Fluorescent Dyes/chemistry , In Situ Hybridization, Fluorescence/methods , Cryptococcosis/blood , Cryptococcosis/cerebrospinal fluid , Cryptococcus neoformans/genetics , DNA Probes/genetics , Humans , Molecular Diagnostic Techniques/methods
13.
J Vet Intern Med ; 24(6): 1427-38, 2010.
Article in English | MEDLINE | ID: mdl-21054543

ABSTRACT

BACKGROUND: Cryptococcus spp. is a fungal pathogen with a predilection for the central nervous system (CNS). OBJECTIVES: To compare the clinical, advanced imaging, and neuropathologic findings in dogs and cats with CNS cryptococcosis, and to evaluate outcome of treatment in these animals. ANIMALS: Twenty-six cats and 21 dogs with CNS cryptococcosis. METHODS: Medical records were reviewed for clinical findings and results of CNS imaging. Archived cerebrospinal fluid and CNS tissue specimens were reviewed for pathology. Findings in cats were compared with those in dogs and the effects of variables on survival were determined by survival curve analysis. RESULTS: When present, pain was localized to the cervical region in dogs and was generalized or localized to the thoracolumbar spine or pelvic limbs in cats. Magnetic resonance imaging (MRI) findings were variable but correlated with CNS histopathological findings of meningitis, meningitis with gelatinous pseudocyst formation, and granulomatous mass lesions. Peripherally enhancing brain lesions were seen only in cats. Histopathologically, the inflammatory response was milder in cats compared with dogs. Remissions of ≥1 year occurred in 32% of treated animals. Altered mentation was associated with negative outcome. Glucocorticoid use after diagnosis was associated with improved survival in the first 10 days. CONCLUSIONS AND CLINICAL IMPORTANCE: Lesions seen on MRI reflected neuropathological findings and were similar to those reported in human patients. The immune response to infection may differ between cats and dogs, or relate to the infecting cryptococcal species. Long-term (>6 month median survival time) survival may be possible in animals surviving ≥4 days after diagnosis.


Subject(s)
Cat Diseases/diagnosis , Central Nervous System Infections/veterinary , Cryptococcosis/veterinary , Dog Diseases/diagnosis , Animals , California/epidemiology , Cat Diseases/cerebrospinal fluid , Cat Diseases/epidemiology , Cat Diseases/pathology , Cats , Central Nervous System Infections/cerebrospinal fluid , Central Nervous System Infections/epidemiology , Central Nervous System Infections/pathology , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/epidemiology , Cryptococcosis/pathology , Dog Diseases/cerebrospinal fluid , Dog Diseases/epidemiology , Dog Diseases/pathology , Dogs , Magnetic Resonance Imaging/veterinary
15.
J Microbiol Methods ; 177: 106046, 2020 10.
Article in English | MEDLINE | ID: mdl-32920020

ABSTRACT

We prepared a newer growth medium, banana peel extract agar (BPEA) containing the extracts of chopped banana peels for the selective cultivation of Cryptococcus neoformans. Over the medium, the growth resulted in the development of light to the dark brown coloured colonies indicating the chromogenic potential of the BPEA. The organism grown over BPEA was subsequently confirmed as C. neoformans by phenotypic as well as by molecular method. This medium, being cost-effective, may be used in resource-poor settings of the developing or underdeveloped countries for selective isolation of C. neoformans.


Subject(s)
Bacteriological Techniques/methods , Cryptococcus neoformans/growth & development , Cryptococcus neoformans/isolation & purification , Culture Media/chemistry , Musa/chemistry , Plant Extracts/chemistry , Agar , Cerebrospinal Fluid/microbiology , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/diagnosis , Cryptococcosis/microbiology , Cryptococcus neoformans/genetics , DNA, Bacterial/isolation & purification , Meningoencephalitis/cerebrospinal fluid , Meningoencephalitis/diagnosis , Meningoencephalitis/microbiology
16.
Medicine (Baltimore) ; 99(50): e23213, 2020 Dec 11.
Article in English | MEDLINE | ID: mdl-33327239

ABSTRACT

Cryptococcosis caused by Cryptococcus gattii, is a life threatening fungal infection with recently increasing prevalence. C. gattii is a species complex comprising multiple independent species. However, many biological characteristics and clinical features of cryptococcosis due to C. gattii are relatively less well defined. In this paper, we identify two cases of C. gattii infection, and laboratory findings of genotype VGI and VGII in two groups of apparently immunocompetent Chinese individuals respectively. Upon detailed review of all 35 cases of C. gattii infections, it was observed that C. gattii can cause debilitating illness in both immunocompetent and immunocompromised individuals. Cryptococcosis due to C. gattii is a serious systemic fungal infection, with pulmonary central nervous system tropism. Epidemiologically, C. gattii infection is not only restricted in tropical and subtropical regions, but also in other geographical settings.


Subject(s)
Central Nervous System Fungal Infections/diagnosis , Cryptococcosis/diagnosis , Cryptococcosis/microbiology , Cryptococcus gattii/genetics , Administration, Intravenous , Adolescent , Adult , Aged , Amphotericin B/administration & dosage , Amphotericin B/therapeutic use , Antifungal Agents/administration & dosage , Antifungal Agents/therapeutic use , Asian People/genetics , Central Nervous System Fungal Infections/cerebrospinal fluid , Central Nervous System Fungal Infections/epidemiology , Central Nervous System Fungal Infections/microbiology , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/drug therapy , Drug Therapy, Combination , Female , Flucytosine/administration & dosage , Flucytosine/therapeutic use , Genotype , Geography , Humans , Immunocompromised Host/immunology , Male , Middle Aged , Prevalence , Recurrence , Spinal Puncture/methods , Treatment Outcome , Treatment Refusal , Young Adult
17.
New Microbiol ; 32(2): 209-12, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19579702

ABSTRACT

Immune reconstitution inflammatory syndrome (IRIS) in HIV-1-infected patients is associated with an exaggerated inflammatory response against an opportunistic infection during highly active antiretroviral therapy. The only review on IRIS associated with Criptococcus neoformans reported 21 episodes including lymphadenitis, necrotizing pneumonitis, breast and cutaneous abscess, and cryptococcomas. To our knowledge this is the first report of IRIS associated with previous meningeal criptococcal infection which required neurosurgical intervention with placement of a ventriculo-peritoneal shunt to drain a CSF cyst formed by exclusion of the temporal horn of the right lateral ventricle. We demonstrate that this procedure is possible without complications such as cryptococcal dissemination into the peritoneum.


Subject(s)
AIDS-Related Opportunistic Infections/microbiology , Antiretroviral Therapy, Highly Active/adverse effects , Cryptococcosis/cerebrospinal fluid , Immune Reconstitution Inflammatory Syndrome/chemically induced , Immune Reconstitution Inflammatory Syndrome/surgery , AIDS-Related Opportunistic Infections/cerebrospinal fluid , AIDS-Related Opportunistic Infections/drug therapy , Antifungal Agents/therapeutic use , Brain/pathology , Cryptococcosis/drug therapy , Cryptococcosis/microbiology , Cryptococcus neoformans/drug effects , Cryptococcus neoformans/metabolism , Female , Fluconazole/therapeutic use , HIV-1/drug effects , Humans , Immune Reconstitution Inflammatory Syndrome/pathology , Middle Aged , Ventriculoperitoneal Shunt
18.
Am J Clin Pathol ; 151(2): 198-204, 2019 01 07.
Article in English | MEDLINE | ID: mdl-30321269

ABSTRACT

Objectives: Cryptococcal meningoencephalitis is the most common fungal infection of the central nervous system diagnosed by cerebrospinal fluid cytology (CSF) studies. Existing literature suggests that routine CSF cytomorphologic evaluations are exquisitely specific; however, less is known about their sensitivity. Methods: An electronic record review of the cytopathology and microbiology files was conducted for the 21-year interval from January 1, 1995, through December 31, 2015. Results: In 21 years, 12,584 CSF samples were processed in the laboratory. Of these, 24 (0.2%) were reported positive for cryptococcal organisms by light microscopy, and 129 CSF fungal cultures were positive for Cryptococcus species. All cotested specimens with positive cytology results were positive on culture (15 specimens, 100% specificity). Twenty-four samples with positive culture results were negative by CSF cytology (sensitivity 39%). Conclusions: When culture is used as a gold standard, CSF cytology is 100% specific and 39% sensitive, with a positive predictive value of 100% and a negative predictive value of 99.8%.


Subject(s)
Antigens, Fungal/cerebrospinal fluid , Cryptococcosis/diagnosis , Cryptococcus/immunology , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/microbiology , Cryptococcus/isolation & purification , Cytodiagnosis , Electronic Health Records , Humans , Predictive Value of Tests , Retrospective Studies , Sensitivity and Specificity
19.
J Acquir Immune Defic Syndr ; 82(1): 81-87, 2019 09 01.
Article in English | MEDLINE | ID: mdl-31408451

ABSTRACT

BACKGROUND: The prevalence of cryptococcosis in people living with HIV (PLWH) in the developed world has decreased considerably in the modern antiretroviral therapy (ART) era. Although early mortality of PLWH with opportunistic infections is well understood, overall mortality has not been previously evaluated. METHODS: We conducted a retrospective cohort study of cryptococcosis in PLWH from January 1, 2002, to July 1, 2017. Data were also evaluated before and after 2008 to evaluate the possible effect of modern ART on outcomes. Death date was obtained from the hospital's medical informatics database and the Social Security Death Index. Participants were grouped as survivors, early-mortality (death <90 days), and late-mortality (death ≥90 days) individuals. RESULTS: We reviewed 105 PLWH with cryptococcosis, with 55 survivors (52.4%), 17 early-mortality (16.2%), and 33 late-mortality individuals (31.4%). Overall, mortality was 47.6% (n = 50) with a median follow-up of 3.7 years (interquartile range 1.1, 8.1 years). Late-mortality individuals were less likely to be virally suppressed at the last observation compared with survivors (24% vs 62%, P < 0.001). Individuals diagnosed in the modern ART era had significantly lower mortality (hazard ratio 0.5, confidence interval: 0.2 to 0.8) and were more likely to be virally suppressed at the last observation (57% vs 29%, P = 0.003). Individuals with government-provided insurance had a higher mortality compared to those with private insurance (hazard ratio 2.8, confidence interval: 1.1 to 7.2, P = 0.013). CONCLUSIONS: Despite improvements in ART, PLWH have high mortality after cryptococcal infection that persists beyond their initial hospitalization. Lower mortality was associated with increased HIV viral suppression and private insurance in the modern ART era.


Subject(s)
Anti-HIV Agents/therapeutic use , Cryptococcosis/complications , Cryptococcosis/mortality , HIV Infections/complications , HIV Infections/drug therapy , CD4 Lymphocyte Count , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/diagnosis , Female , Hospitalization , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Missouri , Mortality , Prevalence , Proportional Hazards Models , Retrospective Studies
20.
J Microbiol Methods ; 157: 113-116, 2019 02.
Article in English | MEDLINE | ID: mdl-30639516

ABSTRACT

PURPOSE: Molecular methods provide fast and accurate detection of both bacteria and viruses in the cerebrospinal fluid (CSF) causing infection in the central nervous system (CNS). In the present study we evaluated the bacterial detection performance of the fully automated FilmArray™ Meningitis/Encephalitis (ME) panel (bioMérieux) by comparing it with culture and multiplexed in-house PCR. METHODS: Three sample types were analysed; Contrived samples with known bacterial/fungal concentration (n = 29), clinical samples from patients with verified cause of CNS infection (n = 17) and external quality assessment (EQA) samples (n = 11). Another six samples were purposely prepared with multiple targets to evaluate multiplex capacity. RESULTS: The FilmArray™ had a slightly higher limit of detection for Streptococcus pneumoniae, Neisseria meningitidis, Listeria monocytogenes and Streptococcus agalactiae compared to in-house PCR methods but performed equal or better when compared to culture. The FilmArray™ ME panel detected the expected pathogen in 17 of 17 clinical samples and yielded detection of three additional viruses of which one was confirmed with comparator techniques. All but one of the EQA samples were correctly detected. CONCLUSIONS: The results of this study are promising and the FilmArray™ ME panel could add to the diagnostic algorithm in CNS-infections. However, the limit of detection for the important pathogens N. meningitidis and S. pneumoniae could be improved.


Subject(s)
Cryptococcus/isolation & purification , Infectious Encephalitis/diagnosis , Meningitis, Bacterial/diagnosis , Meningitis, Fungal/diagnosis , Multiplex Polymerase Chain Reaction/methods , Cryptococcosis/cerebrospinal fluid , Cryptococcosis/diagnosis , Cryptococcus/genetics , Humans , Infectious Encephalitis/cerebrospinal fluid , Infectious Encephalitis/microbiology , Listeria monocytogenes/genetics , Listeria monocytogenes/isolation & purification , Meningitis, Bacterial/cerebrospinal fluid , Meningitis, Bacterial/microbiology , Meningitis, Fungal/cerebrospinal fluid , Meningitis, Fungal/microbiology , Neisseria meningitidis/genetics , Neisseria meningitidis/isolation & purification , Streptococcus agalactiae/genetics , Streptococcus agalactiae/isolation & purification , Streptococcus pneumoniae/genetics , Streptococcus pneumoniae/isolation & purification
SELECTION OF CITATIONS
SEARCH DETAIL