Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 125
Filter
Add more filters

Publication year range
1.
Med Mycol ; 59(7): 720-727, 2021 Jul 06.
Article in English | MEDLINE | ID: mdl-33418569

ABSTRACT

Coccidioides fungi are found primarily in the southwestern United States and are the cause of coccidioidomycosis. Tumor necrosis factor α inhibitors (TNFIs) are therapies for autoimmune and inflammatory conditions; their association with coccidioidomycosis is not well characterized. We aimed to determine the prevalence and characteristics of coccidioidomycosis among TNFI recipients with different inflammatory disorders at a tertiary care center. We retrospectively reviewed the electronic health records of patients at our institution from April 4, 2010 to December 17, 2017, who received TNFIs (infliximab, etanercept, adalimumab, certolizumab pegol, or golimumab) and had positive culture, pathologic, and/or serologic results for coccidioidomycosis. Among 1770 patients identified who received TNFIs, 49 (2.8%) had proven or probable coccidioidomycosis. Of these 49, 28 (57%) were men, 47 (96%) were White, and 42 (86%) had pulmonary coccidioidomycosis. The most common TNFIs used were adalimumab, infliximab, and etanercept. Coccidioidomycosis was identified in 25 of 794 patients with rheumatologic disorders (3.1%), 18 of 783 patients with inflammatory bowel disease (IBD) (2.3%), and six of 193 patients with dermatologic disorders (3.1%) (P = .34). There was no difference in coccidioidal infections among recipients of any particular TNFI agents. A minority of patients (7/49, 14%) had an extrapulmonary infection, and the majority of these (6/7) had IBD. Our study shows a low prevalence of coccidioidomycosis in TNFI recipients, even within the Coccidioides-endemic area. Persons with IBD were disproportionately represented among those with extrapulmonary coccidioidomycosis. Treatment with azoles was effective. LAY SUMMARY: Among 1770 patients who received tumor necrosis factor α inhibitors, 49 (2.8%) had newly acquired coccidioidomycosis over a 7-year period. Dissemination occurred in 14.3%, but disproportionately among those with underlying inflammatory bowel disease. All patients recovered with medical management.


Subject(s)
Coccidioidomycosis/epidemiology , Inflammation/drug therapy , Tumor Necrosis Factor Inhibitors/therapeutic use , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adult , Aged , Coccidioides/pathogenicity , Coccidioidomycosis/etiology , Humans , Inflammation/classification , Inflammatory Bowel Diseases/drug therapy , Middle Aged , Prevalence , Retrospective Studies , Southwestern United States/epidemiology , Tumor Necrosis Factor Inhibitors/adverse effects , Tumor Necrosis Factor Inhibitors/classification , Young Adult
2.
Article in English | MEDLINE | ID: mdl-30455238

ABSTRACT

Coccidioidomycosis is a systemic fungal infection caused by the inhalation of the arthroconidia of either of two closely related dimorphic fungi, Coccidioides immitis and C. posadasii, that are endemic in the southwestern United States and other areas in the Western Hemisphere. Chronic cavitary pulmonary infections and extrapulmonary sites of infection are very difficult to treat and often require lifelong azole therapy. APX001A is the first in a new class of broad-spectrum antifungal agents that inhibit Gwt1, an enzyme which is required for cell wall localization of glycosylphosphatidylinositol (GPI)-anchored mannoproteins in fungi. APX001A and several analogs were highly active against clinical isolates of Coccidioides, inhibiting hyphal growth at low nanogram/ml concentrations. APX001 is the N-phosphonooxymethyl prodrug of APX001A, currently in clinical trials for the treatment of invasive fungal infections. Mice were treated orally once daily with 26 mg/kg/day of APX001 and the prodrug analog APX2097, 2 h after administration of the pan-cytochrome P450 inhibitor 1-aminobenzotriazole, which was used to enhance drug half-life and exposures to more closely mimic human pharmacokinetics of APX001A. Five days of treatment reduced lung colony counts by nearly 3 logs and prevented dissemination, similar to the efficacy of fluconazole dosed orally at 25 mg/kg twice daily. In a survival experiment, both APX001- and APX2097-treated mice survived significantly longer than control and fluconazole-treated mice. APX001 and other members of this new class of antifungal agents may offer great promise as effective therapies for coccidioidomycosis.


Subject(s)
Aminopyridines/therapeutic use , Antifungal Agents/therapeutic use , Coccidioides/pathogenicity , Isoxazoles/therapeutic use , Pneumonia/drug therapy , Amphotericin B/therapeutic use , Animals , Coccidioides/drug effects , Disease Models, Animal , Female , Fluconazole/therapeutic use , Mice , Mice, Inbred C57BL , Microbial Sensitivity Tests , Prodrugs/therapeutic use , Triazoles/therapeutic use
3.
BMC Infect Dis ; 19(1): 722, 2019 Aug 16.
Article in English | MEDLINE | ID: mdl-31420023

ABSTRACT

BACKGROUND: Coccidioides spp. are dimorphic fungi endemic to Central America, regions of South America and southwestern USA. Two species cause most human disease: Coccidioides immitis (primarily California isolates) and Coccidioides posadasii. Coccidioidomycosis is typically acquired through inhalation of soil or dust containing spores. Coccidioidal meningitis (CM), most common in the immunocompromised host, can also affect immunocompetent hosts. CASE PRESENTATION: We report a case of C. posadasii meningoencephalitis in a previously healthy 42-year-old Caucasian male who returned to Canada after spending time working in New Mexico. He presented with a 3-week history of headache, malaise and low-grade fevers. He developed progressive confusion and decreasing level of consciousness following hospitalization. Evidence of hydrocephalus and leptomeningeal enhancement was demonstrated on magnetic resonance imaging (MRI) of his brain. Serologic and PCR testing of the patient's CSF confirmed Coccidioides posadasii. Despite appropriate antifungal therapy he continues to have significant short-term memory deficits and has not returned to his full baseline functional status. CONCLUSIONS: Travel to endemic regions can result in disease secondary to Coccidioides spp. and requires physicians in non-endemic areas to have a high index of suspicion. Effective therapeutic options have reduced the mortality rate of CM, however, it is still associated with significant morbidity and requires life-long therapy.


Subject(s)
Antifungal Agents/therapeutic use , Coccidioidomycosis/microbiology , Meningitis, Fungal/microbiology , Meningoencephalitis/microbiology , Adult , Antitubercular Agents/therapeutic use , Brain/diagnostic imaging , Brain/microbiology , Brain/pathology , Canada , Coccidioides/genetics , Coccidioides/pathogenicity , Coccidioidomycosis/drug therapy , Humans , Immunocompetence , Immunoglobulin M/cerebrospinal fluid , Magnetic Resonance Imaging , Male , Meningitis, Fungal/diagnostic imaging , Meningitis, Fungal/drug therapy , Meningoencephalitis/drug therapy , New Mexico , Travel
4.
Article in English | MEDLINE | ID: mdl-29437615

ABSTRACT

Coccidioidal meningitis can cause significant morbidity, and lifelong antifungal therapy is often required. VT-1598 is a fungus-specific Cyp51 inhibitor that has potent in vitro activity against Coccidioides species. We evaluated the in vivo efficacy of VT-1598 in murine models of central nervous system coccidioidomycosis caused by C. posadasii and C. immitis Infection was introduced via intracranial inoculation, and therapy began 48 h postinoculation. Oral treatments consisted of vehicle control, VT-1598, and positive controls of fluconazole in the C. immitis study and VT-1161 in the C. posadasii study. Treatment continued for 7 and 14 days in the fungal-burden and survival studies, respectively. Fungal burden was assessed in brain tissue collected 24 to 48 h posttreatment in the fungal-burden studies, on the days the mice succumbed to infection, or at prespecified endpoints in the survival studies. VT-1598 plasma concentrations were also measured in the C. posadasii study. VT-1598 resulted in significant improvements in survival in mice infected with either species. In addition, the fungal burden was significantly reduced in the fungal-burden studies. Plasma concentrations 48 h after dosing stopped remained above the VT-1598 MIC against the C. posadasii isolate, although levels were undetectable in the survival study after a 4-week washout. Whereas fungal burden remained suppressed after a 2-week washout in the C. immitis model, a higher fungal burden was observed in the survival arm of the C. posadasii model. This in vivo efficacy supports human studies to establish the utility of VT-1598 for the treatment of coccidioidomycosis.


Subject(s)
14-alpha Demethylase Inhibitors/therapeutic use , Coccidioides/drug effects , Coccidioides/pathogenicity , Coccidioidomycosis/drug therapy , Animals , Fluconazole/therapeutic use , Male , Mice , Mice, Inbred ICR , Microbial Sensitivity Tests , Models, Theoretical
5.
Am J Transplant ; 16(12): 3562-3567, 2016 12.
Article in English | MEDLINE | ID: mdl-27376472

ABSTRACT

Donor-derived coccidioidomycosis has caused unexpected morbidity and mortality in transplant recipients. All proven or probable reports of donor-derived coccidioidomycosis to the Disease Transmission Advisory Committee between 2005 and August 2012 were reviewed. Six reports of proven or probable coccidioidomycosis were discovered. In four of six, the infection was first detected at autopsy in the recipient. In two cases it was first identified in the donor. Twenty-one recipients received organs from these six donors. Transmission occurred in 43% at a median of 30 days posttransplant with a mortality rate of 28.5%. Eleven recipients received preemptive antifungals, seven did not receive treatment, and treatment information was not reported for three recipients. Five of seven who did not receive prophylaxis/treatment died and all 11 who received early therapy survived. Six deaths occurred 14 to 55 days after transplant, with a median of 21 days. For exposed recipients, donor-derived coccidioidomycosis is a significant cause of morbidity and mortality. Evidence of infection in one recipient should prompt immediate evaluation for treatment of all other recipients from the same donor as preemptive treatment was effective. Further studies are needed to decide whether all donors from endemic areas should have routine serologic screening.


Subject(s)
Coccidioides/pathogenicity , Coccidioidomycosis/transmission , Disease Transmission, Infectious , Organ Transplantation/adverse effects , Tissue Donors , Advisory Committees , Coccidioidomycosis/epidemiology , Coccidioidomycosis/etiology , Donor Selection , Humans , Patient Safety , Prognosis , Risk Assessment , Tissue and Organ Procurement , Transplant Recipients , United States/epidemiology
6.
Emerg Infect Dis ; 21(11): 1997-2005, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26484688

ABSTRACT

Coccidioidomycosis is associated with soil-disruptive work in Coccidioides-endemic areas of the southwestern United States. Among 3,572 workers constructing 2 solar power-generating facilities in San Luis Obispo County, California, USA, we identified 44 patients with symptom onset during October 2011-April 2014 (attack rate 1.2 cases/100 workers). Of these 44 patients, 20 resided in California outside San Luis Obispo County and 10 resided in another state; 9 were hospitalized (median 3 days), 34 missed work (median 22 days), and 2 had disseminated disease. Of the 25 patients who frequently performed soil-disruptive work, 6 reported frequent use of respiratory protection. As solar farm construction in Coccidioides-endemic areas increases, additional workers will probably be exposed and infected unless awareness is emphasized and effective exposure reduction measures implemented, including limiting dust generation and providing respiratory protection. Medical providers, including those in non-Coccidioides-endemic areas, should suspect coccidioidomycosis in workers with compatible illness and report cases to their local health department.


Subject(s)
Coccidioidomycosis/epidemiology , Disease Outbreaks , Adult , California/epidemiology , Coccidioides/pathogenicity , Coccidioidomycosis/economics , Female , Hospitalization/economics , Humans , Incidence , Male , Middle Aged , Solar Energy
7.
Mycoses ; 58(10): 598-602, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26393436

ABSTRACT

The goal of this study was to report on the potential utility of cerebrospinal fluid (CSF) Coccidioides antigen testing in the diagnosis and management of Coccidioides meningitis. We retrospectively reviewed medical records of seven patients with Coccidioides meningitis who had Coccidioides antigen tests performed on CSF. In two severely immunocompromised patients, CSF Coccidioides antigen testing was helpful in the diagnosis when other testing modalities were negative. Coccidioides antigen testing was also useful in the management of patients who had progression of disease due to non-adherence, development of resistance, failure of therapy and the presence of vasculitis. Changing antigen levels helped identify disease complications in three patients that led to alterations in therapy or management. On the basis of our review of these seven patients with Coccidioides meningitis, we concluded that the Coccidioides antigen test contributed to the diagnosis and management of patients with Coccidioides meningitis.


Subject(s)
Antigens, Fungal/analysis , Antigens, Fungal/cerebrospinal fluid , Central Nervous System/microbiology , Coccidioidomycosis/cerebrospinal fluid , Coccidioidomycosis/diagnosis , Meningitis, Fungal/diagnosis , Adult , Coccidioides/immunology , Coccidioides/pathogenicity , Coccidioidomycosis/complications , Coccidioidomycosis/immunology , Female , Humans , Immunoassay , Immunocompromised Host , Male , Meningitis, Fungal/drug therapy , Meningitis, Fungal/microbiology , Middle Aged , Retrospective Studies
8.
Mycopathologia ; 179(1-2): 1-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25318989

ABSTRACT

Coccidioidomycosis ('Valley Fever'), caused by the inhalation of the fungus Coccidioides, remains a recalcitrant health problem in large parts of California. The incidence and severity of the disease continues to rise in many parts of the state. In this manuscript, we highlight unanswered questions about the disease. Specifically, the extent of disease burden, genetic determinants of host susceptibility, diagnostic and treatment guidelines, natural reservoirs of the pathogens, antifungal drug resistance, and fungal determinants of mild or severe disease are all areas awaiting in depth investigations. We also recommend establishment of a California Coccidioidomycosis Registry to improve clinical care and translational research.


Subject(s)
Coccidioides/drug effects , Coccidioidomycosis/drug therapy , Coccidioidomycosis/epidemiology , Disease Reservoirs/microbiology , California/epidemiology , Coccidioides/genetics , Coccidioides/pathogenicity , Coccidioidomycosis/diagnosis , Drug Resistance, Fungal/genetics , Humans
9.
Emerg Infect Dis ; 20(6): 983-90, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24865953

ABSTRACT

In Arizona, USA, primary pulmonary coccidioidomycosis accounts for 15%-29% of community-acquired pneumonia. To determine the evolution of symptoms and changes in laboratory values for patients with mild to moderate coccidioidomycosis during 2010-2012, we conducted a prospective 24-week study of patients with primary pulmonary coccidioidomycosis. Of the 36 patients, 16 (44%) were men and 33 (92%) were White. Median age was 53 years, and 20 (56%) had received antifungal treatment at baseline. Symptom scores were higher for patients who received treatment than for those who did not. Median times from symptom onset to 50% reduction and to complete resolution for patients in treatment and nontreatment groups were 9.9 and 9.1 weeks, and 18.7 and 17.8 weeks, respectively. Median times to full return to work were 8.4 and 5.7 weeks, respectively. One patient who received treatment experienced disseminated infection. For otherwise healthy adults with acute coccidioidomycosis, convalescence was prolonged, regardless of whether they received antifungal treatment.


Subject(s)
Coccidioides/pathogenicity , Coccidioidomycosis/physiopathology , Convalescence , Lung Diseases, Fungal/physiopathology , Pneumonia/physiopathology , Adult , Aged , Antifungal Agents/therapeutic use , Arizona/epidemiology , Coccidioides/drug effects , Coccidioides/growth & development , Coccidioidomycosis/drug therapy , Coccidioidomycosis/epidemiology , Coccidioidomycosis/microbiology , Community-Acquired Infections , Female , Humans , Lung Diseases, Fungal/drug therapy , Lung Diseases, Fungal/epidemiology , Lung Diseases, Fungal/microbiology , Male , Middle Aged , Pneumonia/drug therapy , Pneumonia/epidemiology , Pneumonia/microbiology , Prospective Studies , Severity of Illness Index
10.
Med Mycol ; 52(2): 149-55, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24576996

ABSTRACT

Coccidioides immitis and C. posadasii, the causative agents of the mammalian disease coccidioidomycosis, are dimorphic fungal pathogens distributed throughout desert-like environments in North and South America. Coccidioides spp. are members of the Onygenales, a diverse group of pathogenic and nonpathogenic fungi. Recently, full genomes have been published for Coccidioides and a number of other Onygenales species. Phylogenomic comparisons and additional studies in Coccidioides population genomics and gene expression have shed light on the ecology and pathogenesis of Coccidioides and the other medically important species in this clade. Observed patterns of gene family expansion/contraction and evidence of gene flow have provided insight to the evolution of Coccidioides and greatly broadened our understanding of the diversity and sources of genetic variation found in fungi. In the future, expansion of the number of sequenced isolates from all populations will allow deeper insight into the evolutionary processes that have shaped this unique human pathogen. In addition, deep sequencing of isolates from a single Coccidioides population and pairing of those data with phenotype information on growth and pathogenicity for genome-wide association analysis will allow researchers to find genes responsible for any phenotype, virulence included, that shows variation in the population.


Subject(s)
Coccidioides/genetics , Coccidioides/pathogenicity , Coccidioidomycosis/microbiology , Ecology , Genomics , Americas/epidemiology , Coccidioidomycosis/epidemiology , Evolution, Molecular , Genes, Fungal , Humans , Virulence , Virulence Factors/genetics
11.
Semin Cutan Med Surg ; 33(3): 140-5, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25577855

ABSTRACT

Coccidioidomycosis is a common, environmentally acquired, pulmonary fungal infection in arid and semi-arid regions of the West, especially Arizona and California. The infection is frequently associated with striking cutaneous manifestations. Reactive, immunologically mediated eruptions include erythema nodosum, a generalized exanthem, Sweet syndrome, and reactive granulomatous dermatitis. Less commonly, the skin can harbor the actual organisms as a result of dissemination from the lungs. Dermatologists may play a key role in the recognition of coccidioidomycosis


Subject(s)
Coccidioidomycosis/diagnosis , Coccidioidomycosis/drug therapy , Biopsy , Coccidioides/classification , Coccidioides/pathogenicity , Coccidioides/ultrastructure , Coccidioidomycosis/pathology , Coccidioidomycosis/transmission , Dermatomycoses/diagnosis , Dermatomycoses/drug therapy , Dermatomycoses/pathology , Dermatomycoses/transmission , Diagnosis, Differential , Humans , Lung Diseases, Fungal/diagnosis , Lung Diseases, Fungal/drug therapy , Lung Diseases, Fungal/pathology , Lung Diseases, Fungal/transmission , Skin/pathology
12.
Microb Pathog ; 59-60: 19-28, 2013.
Article in English | MEDLINE | ID: mdl-23583291

ABSTRACT

Coccidioides is the causative agent of a potentially life-threatening respiratory disease of humans. A feature of this mycosis is that pH measurements of the microenvironment of pulmonary abscesses are consistently alkaline due to ammonia production during the parasitic cycle. We previously showed that enzymatically active urease is partly responsible for elevated concentrations of extracellular ammonia at sites of lung infection and contributes to both localized host tissue damage and exacerbation of the respiratory disease in BALB/c mice. Disruption of the urease gene (URE) of Coccidioides posadasii only partially reduced the amount of ammonia detected during in vitro growth of the parasitic phase, suggesting that other ammonia-producing pathways exist that may also contribute to the virulence of this pathogen. Ureidoglycolate hydrolase (Ugh) expressed by bacteria, fungi and higher plants catalyzes the hydrolysis of ureidoglycolate to yield glyoxylate and the release CO2 and ammonia. This enzymatic pathway is absent in mice and humans. Ureidoglycolate hydrolase gene deletions were conducted in a wild type (WT) isolate of C. posadasii as well as the previously generated Δure knock-out strain. Restorations of UGH in the mutant stains were performed to generate and evaluate the respective revertants. The double mutant revealed a marked decrease in the amount of extracellular ammonia without loss of reproductive competence in vitro compared to both the WT and Δure parental strains. BALB/c mice challenged intranasally with the Δugh/Δure mutant showed 90% survival after 30 days, decreased fungal burden, and well-organized pulmonary granulomas. We conclude that loss of both Ugh and Ure activity significantly reduced the virulence of this fungal pathogen.


Subject(s)
Amidine-Lyases/metabolism , Ammonia/metabolism , Coccidioides/metabolism , Coccidioides/pathogenicity , Coccidioidomycosis/pathology , Lung Diseases, Fungal/pathology , Urease/metabolism , Amidine-Lyases/genetics , Animals , Coccidioides/enzymology , Coccidioides/genetics , Coccidioidomycosis/microbiology , Disease Models, Animal , Gene Knockout Techniques , Humans , Lung Diseases, Fungal/microbiology , Mice , Mice, Inbred BALB C , Survival Analysis , Urease/genetics , Virulence
13.
Klin Lab Diagn ; (4): 43-5, 2013 Apr.
Article in Russian | MEDLINE | ID: mdl-23984556

ABSTRACT

The article deals with analysis of morphologic characteristics of microscopic fungi of genus of Coccididoides spp. under cultivation on culture of mouse splenocytes culture. During two days, the strains of C. imitis and C. posadasii converse from filamentous to spherulic form. This process makes it possible to apply this test to identify agents of coccidioidomycosis.


Subject(s)
Coccidioides/isolation & purification , Coccidioidomycosis/microbiology , Animals , Coccidioides/growth & development , Coccidioides/pathogenicity , Coccidioidomycosis/pathology , Fungi/growth & development , Fungi/isolation & purification , Fungi/pathogenicity , Mice , Mycelium/growth & development , Mycelium/isolation & purification , Mycelium/pathogenicity , Spleen/cytology , Spleen/growth & development , Spleen/microbiology
14.
BMC Microbiol ; 12: 218, 2012 Sep 24.
Article in English | MEDLINE | ID: mdl-23006927

ABSTRACT

BACKGROUND: Coccidioidomycosis results from airborne infections caused by either Coccidioides immitis or C. posadasii. Both are pathogenic fungi that live in desert soil in the New World and can infect normal hosts, but most infections are self-limited. Disseminated infections occur in approximately 5% of cases and may prove fatal. Mouse models of the disease have identified strains that are resistant (e.g. DBA/2) or susceptible (e.g. C57BL/6) to these pathogens. However, the genetic and immunological basis for this difference has not been fully characterized. RESULTS: Microarray technology was used to identify genes that were differentially expressed in lung tissue between resistant DBA/2 and sensitive C57BL/6 mice after infection with C. immitis. Differentially expressed genes were mapped onto biological pathways, gene ontologies, and protein interaction networks, which revealed that innate immune responses mediated by Type II interferon (i.e., IFNG) and the signal transducer and activator of transcription 1 (STAT1) contribute to the resistant phenotype. In addition, upregulation of hypoxia inducible factor 1A (HIF1A), possibly as part of a larger inflammatory response mediated by tumor necrosis factor alpha (TNFA), may also contribute to resistance. Microarray gene expression was confirmed by real-time quantitative PCR for a subset of 12 genes, which revealed that IFNG HIF1A and TNFA, among others, were significantly differentially expressed between the two strains at day 14 post-infection. CONCLUSION: These results confirm the finding that DBA/2 mice express more Type II interferon and interferon stimulated genes than genetically susceptible strains and suggest that differential expression of HIF1A may also play a role in protection.


Subject(s)
Coccidioides/immunology , Coccidioidomycosis/genetics , Coccidioidomycosis/immunology , Host-Pathogen Interactions , Hypoxia-Inducible Factor 1, alpha Subunit/immunology , Interferon-gamma/immunology , Animals , Coccidioides/pathogenicity , Disease Models, Animal , Gene Expression Profiling , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Microarray Analysis
15.
Eukaryot Cell ; 10(1): 34-42, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21076011

ABSTRACT

Because most fungi have evolved to be free-living in the environment and because the infections they cause are usually opportunistic in nature, it is often difficult to identify specific traits that contribute to fungal pathogenesis. In recent years, there has been a surge in the number of sequenced genomes of human fungal pathogens, and comparison of these sequences has proved to be an excellent resource for exploring commonalities and differences in how these species interact with their hosts. In order to survive in the human body, fungi must be able to adapt to new nutrient sources and environmental stresses. Therefore, genes involved in carbohydrate and amino acid metabolism and transport and genes encoding secondary metabolites tend to be overrepresented in pathogenic species (e.g., Aspergillus fumigatus). However, it is clear that human commensal yeast species such as Candida albicans have also evolved a range of specific factors that facilitate direct interaction with host tissues. The evolution of virulence across the human pathogenic fungi has occurred largely through very similar mechanisms. One of the most important mechanisms is gene duplication and the expansion of gene families, particularly in subtelomeric regions. Unlike the case for prokaryotic pathogens, horizontal transfer of genes between species and other genera does not seem to have played a significant role in the evolution of fungal virulence. New sequencing technologies promise the prospect of even greater numbers of genome sequences, facilitating the sequencing of multiple genomes and transcriptomes within individual species, and will undoubtedly contribute to a deeper insight into fungal pathogenesis.


Subject(s)
Evolution, Molecular , Fungi/genetics , Fungi/pathogenicity , Aspergillus/genetics , Aspergillus/pathogenicity , Candida/genetics , Candida/pathogenicity , Coccidioides/genetics , Coccidioides/pathogenicity , Cryptococcus/genetics , Cryptococcus/pathogenicity , Genome-Wide Association Study , Humans , Virulence Factors/genetics
16.
BMC Microbiol ; 11: 108, 2011 May 16.
Article in English | MEDLINE | ID: mdl-21575248

ABSTRACT

BACKGROUND: Since 1991 several outbreaks of acute coccidioidomycosis (CM) were diagnosed in the semi-arid Northeast of Brazil, mainly related to disturbance of armadillo burrows caused by hunters while digging them for the capture of these animals. This activity causes dust contaminated with arthroconidia of Coccidioides posadasii, which, once inhaled, cause the mycosis. We report on the identification of C. posadasii in soil samples related to outbreaks of CM. RESULTS: Twenty four soil samples had their DNA extracted and subsequently submitted to a semi-nested PCR technique using specific primers. While only 6 (25%) soil samples were positive for C. posadasii by mice inoculation, all (100%) were positive by the molecular tool. CONCLUSION: This methodology represents a simple, sensitive and specific molecular technique to determine the environmental distribution of Coccidioides spp. in endemic areas, but cannot distinguish the species. Moreover, it may be useful to identify culture isolates. Key-words: 1. Coccidioidomycosis. 2. Coccidioides spp. 3. C. posadasii. 4. Semi-arid. 5. Semi-nested PCR.


Subject(s)
Coccidioides/classification , Coccidioides/isolation & purification , Mycology/methods , Polymerase Chain Reaction/methods , Soil Microbiology , Animal Experimentation , Animals , Brazil , Coccidioides/genetics , Coccidioides/pathogenicity , Mice , Mycoses/microbiology , Mycoses/pathology , Sensitivity and Specificity
17.
Microb Pathog ; 51(6): 432-41, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21896326

ABSTRACT

Production of reactive oxygen species (ROS) resulting from phagocytic NADPH oxidase (NOX2) activity has been reported to contribute to host defense against numerous microbial pathogens. In this study we explored the role of NOX2 production in experimental coccidioidomycosis, a human respiratory disease caused by a soil-borne fungal pathogen. Activated and non-activated macrophages isolated from either NOX2(-/-) knock-out or wild type (WT) mice showed comparable ROS production and killing efficiency in vitro when infected with parasitic cells of Coccidioides. Both mouse strains also revealed similar fungal burden in their lungs and spleen at 7 and 11 days after intranasal challenge with Coccidioides spores, although the NOX2(-/-) mice died earlier than the WT strain. Immunization of the NOX2(-/-) and WT mice with a live, attenuated vaccine strain of Coccidioides also resulted in comparable reduction of the fungal burden in both lungs and spleen. These combined results initially suggested that NOX2 activity and ROS production are not essential for protection against Coccidioides infection. However, the reduced survival of non-vaccinated NOX2(-/-) mice correlated with high, sustained numbers of lung-infiltrated neutrophils on days 7 and 11 postchallenge, an expansion of the regulatory T cell population in infected lungs in the knock-out mice, and elevated concentrations of pro-inflammatory cytokines and chemokines in lung homogenates compared to infected WT mice. Although NOX2-derived ROS appeared to be dispensable for both innate and acquired immunity to pulmonary Coccidioides infection, evidence is presented that NOX2 production plays a role in limiting pathogenic inflammation in this murine model of coccidioidomycosis.


Subject(s)
Coccidioides/pathogenicity , Coccidioidomycosis/immunology , Inflammation/pathology , Lung/immunology , Membrane Glycoproteins/immunology , NADPH Oxidases/immunology , Phagocytes/enzymology , Animals , Coccidioides/immunology , Colony Count, Microbial , Cytokines/metabolism , Disease Models, Animal , Fungal Vaccines/administration & dosage , Fungal Vaccines/immunology , Lung/pathology , Membrane Glycoproteins/genetics , Mice , Mice, Knockout , NADPH Oxidase 2 , NADPH Oxidases/genetics , Phagocytes/immunology , Reactive Oxygen Species/immunology , Reactive Oxygen Species/metabolism , Spleen/microbiology , Survival Analysis , T-Lymphocytes, Regulatory/immunology , Time Factors
18.
Microb Pathog ; 51(3): 161-8, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21513788

ABSTRACT

The functions of inducible nitric oxide synthase (iNOS) activity in protection against microbial insults are still controversial. In this study, we explored the role of iNOS in protection against Coccidioides infection in mice. We observed that wild type (WT) and iNOS(-/-) mice showed similar percent survival and fungal burden in their lungs at days 7 and 11 after intranasal challenge with Coccidioides. Vaccinated WT and iNOS(-/-) mice revealed comparable fungal burden in their lungs and spleen at 7 and 11 days postchallenge. However, at 11 days the non-vaccinated, iNOS-deficient mice had significantly higher fungal burden in their spleen compared to WT mice. Additionally, higher numbers of lung-infiltrated neutrophils, macrophages and dendritic cells were observed in WT mice at day 11 postchallenge compared to iNOS(-/-) mice. Moreover, no difference in numbers of T, B, NK or regulatory T cells, or concentrations of selected cytokines and chemokines were detected in lungs of both mouse strains at 7 and 11 days postchallenge. Although iNOS-derived NO production appears to influence the inflammatory response and dissemination of the fungal pathogen, our results suggest that iNOS activity does not play a significant role in the control of coccidioidal infection in mice and that other, still undefined mechanisms of host protection are involved.


Subject(s)
Coccidioides/immunology , Coccidioides/pathogenicity , Coccidioidomycosis/immunology , Nitric Oxide Synthase/immunology , Nitric Oxide Synthase/metabolism , Animals , Coccidioidomycosis/mortality , Coccidioidomycosis/pathology , Colony Count, Microbial , Cytokines/immunology , Killer Cells, Natural/immunology , Lung/microbiology , Lymphocytes/immunology , Mice , Mice, Inbred C57BL , Mice, Knockout , Neutrophils/immunology , Nitric Oxide Synthase/deficiency , Spleen/microbiology , Survival Analysis
19.
Semin Respir Crit Care Med ; 32(6): 754-63, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22167403

ABSTRACT

Coccidioidomycosis refers to the spectrum of disease caused by the dimorphic fungi Coccidioides immitis and Coccidioides posadasii. Clinical manifestations vary depending upon both the extent of infection and the immune status of the host. Coccidioidomycosis has been reported to involve almost all organ systems; however, pulmonary disease is the most common clinical manifestation. The incidence of coccidioidomycosis continues to rise, and primary coccidioidal pneumonia accounts for 17 to 29% of all cases of community-acquired pneumonia in endemic regions. The majority of patients with coccidioidomycosis resolve their initial infection without sequelae; however, several patients develop complications of disease ranging in severity from complicated pulmonary coccidioidomycosis to widely disseminated disease with immediately life-threatening manifestations. This review focuses on complications of pulmonary coccidioidomycosis with an emphasis on the management of primary coccidioidal infection, solitary pulmonary nodules, pleural effusions, cavitary disease, acute respiratory distress syndrome (ARDS), miliary disease, and sepsis.


Subject(s)
Antifungal Agents/therapeutic use , Coccidioides/pathogenicity , Coccidioidomycosis/complications , Lung Diseases, Fungal/complications , Coccidioides/immunology , Coccidioidomycosis/diagnosis , Coccidioidomycosis/drug therapy , Coccidioidomycosis/physiopathology , Humans , Lung Diseases, Fungal/diagnosis , Lung Diseases, Fungal/drug therapy , Lung Diseases, Fungal/physiopathology , Pleural Effusion/etiology , Respiratory Distress Syndrome/etiology , Serologic Tests , Solitary Pulmonary Nodule/etiology
20.
New Microbiol ; 34(3): 307-16, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21811752

ABSTRACT

A protein microarray containing fungal antigens (the "mycoarray") has been set up to provide rapid and appropriate serodiagnosis of primitive endemic mycoses, an important cause of morbidity and mortality in an increasingly high number of patients. The mycoarray consists of three antigen extracts (histoplasmin, coccidioidin and Coccidioides "TP") and antibody dilution curves were spotted on microarray slides. The arrays were processed with coccidioidomycosis and histoplasmosis patients� sera or with control sera and the occurring immunocomplexes were detected by indirect immunofluorescence. In agreement with clinical and microbiological diagnosis, the results distinguished between histoplasmosis and coccidioidomycosis patients. In addition, the assay could clearly discriminate between IgM and IgG antibody reactivity. No reactivity was ever observed in the arrays processed with negative control sera. Therefore, this pilot study demonstrates that the "mycoarray" is sensitive and specific enough to discriminate between healthy individuals and patients with histoplasmosis or coccidioidomycosis. Because of miniaturization and multiparametricity, the new assay cuts costs and processing time. Thus, once clinically validated and implemented as a large-scale array, the "mycoarray" will be ready to be applied to the daily clinical practice.


Subject(s)
Antigens, Fungal/analysis , Mycoses/diagnosis , Mycoses/metabolism , Protein Array Analysis/methods , Coccidioides/metabolism , Coccidioides/pathogenicity , Humans , Mycoses/microbiology
SELECTION OF CITATIONS
SEARCH DETAIL