151
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Gamaletsou MN, Sipsas NV, Roilides E, Walsh TJ. Rhino-Orbital-Cerebral Mucormycosis. Curr Infect Dis Rep 2012; 14:423-34. [DOI: 10.1007/s11908-012-0272-6] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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152
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Rammaert B, Lanternier F, Poirée S, Kania R, Lortholary O. Diabetes and mucormycosis: A complex interplay. DIABETES & METABOLISM 2012; 38:193-204. [DOI: 10.1016/j.diabet.2012.01.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Accepted: 01/09/2012] [Indexed: 01/13/2023]
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153
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Su H, Thompson GR, Cohen SH. Hepatic mucormycosis with abscess formation. Diagn Microbiol Infect Dis 2012; 73:192-4. [DOI: 10.1016/j.diagmicrobio.2012.02.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 02/25/2012] [Accepted: 02/27/2012] [Indexed: 11/29/2022]
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154
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Spellberg B, Ibrahim A, Roilides E, Lewis RE, Lortholary O, Petrikkos G, Kontoyiannis DP, Walsh TJ. Combination therapy for mucormycosis: why, what, and how? Clin Infect Dis 2012; 54 Suppl 1:S73-8. [PMID: 22247449 DOI: 10.1093/cid/cir885] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The high mortality rate of mucormycosis with currently available monotherapy, particularly in hematology patients, has stimulated interest in studying novel combinations of antifungal agents to determine whether superior outcomes might be achieved. Combination lipid polyene-echinocandin therapy is the most promising of such regimens based on safety profile, the availability of parenteral formulations of echinocandins, their synergy in murine models of mucormycosis, and observational clinical data that are concordant. Other options include combination lipid polyene plus deferasirox or posaconazole therapy. Definitive, randomized, placebo-controlled phase III clinical trials are needed to determine whether combination therapy with any of these options is superior to monotherapy. Until such studies are conducted, clinicians will continue to be placed in the unacceptable position of not knowing if and when to administer combination therapy. Such a state of confusion may lead to undertreatment if combination therapy is indeed superior but is not used and, conversely, may lead to unacceptable toxicity and cost to patients if combination therapy is not superior but is used. It is critical that sponsors step forward with funding to conduct these clinical trials to determine whether outcomes from these devastating infections can be improved.
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Affiliation(s)
- Brad Spellberg
- Division of General Internal Medicine, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, University of California at Los Angeles, 1124 West Carson St., Torrance, CA 90502, USA.
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155
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Kontoyiannis DP, Lewis RE, Lortholary O, Spellberg B, Petrikkos G, Roilides E, Ibrahim A, Walsh TJ. Future directions in mucormycosis research. Clin Infect Dis 2012; 54 Suppl 1:S79-85. [PMID: 22247450 DOI: 10.1093/cid/cir886] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Mucormycosis has emerged as an important opportunistic infection, especially in severely immunosuppressed hosts. The evolving epidemiology, immunopathogenesis, molecular virulence studies, early diagnosis, and pitfalls in designing clinical studies of mucormycosis are discussed in this article.
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Affiliation(s)
- Dimitrios P Kontoyiannis
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA.
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156
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Ibrahim AS, Spellberg B, Walsh TJ, Kontoyiannis DP. Pathogenesis of mucormycosis. Clin Infect Dis 2012; 54 Suppl 1:S16-22. [PMID: 22247441 DOI: 10.1093/cid/cir865] [Citation(s) in RCA: 430] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mucormycosis is a life-threatening infection that occurs in patients who are immunocompromised because of diabetic ketoacidosis, neutropenia, organ transplantation, and/or increased serum levels of available iron. Because of the increasing prevalence of diabetes mellitus, cancer, and organ transplantation, the number of patients at risk for this deadly infection is increasing. Despite aggressive therapy, which includes disfiguring surgical debridement and frequently adjunctive toxic antifungal therapy, the overall mortality rate is high. New strategies to prevent and treat mucormycosis are urgently needed. Understanding the pathogenesis of mucormycosis and the host response to invading hyphae ultimately will provide targets for novel therapeutic interventions. In this supplement, we review the current knowledge about the virulence traits used by the most common etiologic agent of mucormycosis, Rhizopus oryzae. Because patients with elevated serum levels of available iron are uniquely susceptible to mucormycosis and these infections are highly angioinvasive, emphasis is placed on the ability of the organism to acquire iron from the host and on its interactions with endothelial cells lining blood vessels. Several promising therapeutic strategies in preclinical stages are identified.
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Affiliation(s)
- Ashraf S Ibrahim
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, University of California-Los Angeles, 1124 W Carson St., Torrance, CA 90502, USA.
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157
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Cerebro-rhino orbital mucormycosis: An update. J Infect Public Health 2012; 5:116-26. [DOI: 10.1016/j.jiph.2012.01.003] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 11/07/2011] [Accepted: 01/27/2012] [Indexed: 11/22/2022] Open
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158
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Spellberg B, Kontoyiannis DP, Fredricks D, Morris MI, Perfect JR, Chin-Hong PV, Ibrahim AS, Brass EP. Risk factors for mortality in patients with mucormycosis. Med Mycol 2012; 50:611-8. [PMID: 22435877 DOI: 10.3109/13693786.2012.669502] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Optimal clinical care and clinical investigation of patients with mucormycosis are limited by absence of controlled trials, and absence of well-defined predictors of mortality or clinical response. The Deferasirox-AmBisome Therapy for mucormycosis (DEFEAT Mucor) study was the first randomized clinical trial conducted on patients with mucormycosis, and demonstrated that adjunctive deferasirox therapy did not improve outcomes of the disease. The current study describes clinical factors from the 20 patients enrolled to identify those associated with 90-day mortality of the 11 (55%) patients who died by day 90. Age, diabetes mellitus, transplant status, or antifungal therapy were not associated with mortality. However, active malignancy or neutropenia at enrollment were associated with increased mortality. Pulmonary infection was linked with lower Kaplan-Meier survival compared to non-pulmonary infection. Higher baseline serum concentrations of iron and ferritin were also associated with mortality. No patient who progressed clinically during the first 14 days of study therapy survived; however, many patients who clinically improved during that time did not survive to 90 days. In contrast, day 30 clinical response was predictive of 90-day survival. These factors may be useful in defining enrollment randomization stratification critieria for future clinical trials, and in supporting clinical care of patients with mucormycosis.
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Affiliation(s)
- Brad Spellberg
- Division of General Internal Medicine, Los Angeles Biomedical Research Institute, Harbor-University of California Los Angeles (UCLA) Medical Center, Los Angeles, CA, USA.
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159
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Lanternier F, Sun HY, Ribaud P, Singh N, Kontoyiannis DP, Lortholary O. Mucormycosis in Organ and Stem Cell Transplant Recipients. Clin Infect Dis 2012. [DOI: 10.1093/cid/cis195] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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160
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Luo G, Spellberg B, Gebremariam T, Bolaris M, Lee H, Fu Y, French SW, Ibrahim AS. Diabetic murine models for Acinetobacter baumannii infection. J Antimicrob Chemother 2012; 67:1439-45. [PMID: 22389456 DOI: 10.1093/jac/dks050] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVES Extremely drug-resistant (XDR; i.e. resistant to all antibiotics except colistin or tigecycline) Acinetobacter baumannii has emerged as one of the most common and highly antibiotic-resistant causes of infection. Diabetes is a risk factor for acquisition of and worse outcomes from A. baumannii infection. We sought to develop diabetic mouse models of A. baumannii bacteraemia and pneumonia and validate these models by comparing the efficacy of antibiotic treatment in these models with the established neutropenic mouse models. METHODS Diabetic or neutropenic mice were infected via intravenous inoculation or inhalation in an aerosol chamber with an XDR A. baumannii. Treatment with colistin started 24 h after infection and continued daily for 7 days. Survival served as the primary endpoint while tissue bacterial burden and histopathological examination served as secondary endpoints. RESULTS Lethal infection was achieved for the neutropenic and diabetic mice when infected intravenously or via inhalation. Neutropenic mice were more susceptible to infection than diabetic mice in the pneumonia model and equally susceptible in the bacteraemia model. Both models of bacteraemia were sensitive enough to detect virulence differences among different clinical strains of A. baumannii. In the pneumonia model, colistin treatment was effective in improving survival, reducing lung bacterial burden and histologically resolving the infection compared with placebo only in diabetic mice. CONCLUSIONS We developed novel models of A. baumannii bacteraemia and pneumonia in diabetic mice. These models can be used to study mechanisms of infection, develop immunotherapeutic strategies and evaluate drug efficacies against highly lethal A. baumannii infections.
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Affiliation(s)
- Guanpingsheng Luo
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
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161
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Abstract
Increases in the rates of fungal infections, as well as their associated morbidity and mortality has led to a need for additional antifungal agents. The most common serious fungal agents in immunosuppressed and critically ill patients are Candida spp. and Aspergillus spp., although other emerging fungi must be considered. Rational, early systemic antifungal treatment should be based on diagnostic imaging techniques and conventional mycological and non-culture-based procedures. While the availability of new therapeutic options is an important advance, antifungal therapy has become increasingly complex. In addition to the available antifungal armamentarium, recent research has resulted in the introduction of three new antifungal agents: micafungin, anidulafungin, and posaconazole. This article provides an update, based on the latest scientific evidence, of the clinical efficacy, pharmacokinetics, safety and dosing of antifungal drugs administered in the management of Candida spp., Aspergillus spp., Cryptococcus spp., Zygomycetes, Scedosporium spp. and Fusarium spp.
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Affiliation(s)
- Jesús Fortún
- Servicio de Enfermedades Infecciosas, Hospital Ramón y Cajal, Madrid, España.
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162
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Zhou T, Ma Y, Kong X, Hider RC. Design of iron chelators with therapeutic application. Dalton Trans 2012; 41:6371-89. [DOI: 10.1039/c2dt12159j] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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163
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Tan S, Aronowitz P. A common fungus, an unusual (and deadly) infection. Am J Med 2011; 124:1023-4. [PMID: 22017779 DOI: 10.1016/j.amjmed.2011.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 08/10/2011] [Accepted: 08/10/2011] [Indexed: 11/18/2022]
Affiliation(s)
- Susanna Tan
- Department of Internal Medicine, California Pacific Medical Center, San Francisco, CA, USA.
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164
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Katragkou A, Roilides E. Immunotherapy of infections caused by rare filamentous fungi. Clin Microbiol Infect 2011; 18:134-9. [PMID: 22044625 DOI: 10.1111/j.1469-0691.2011.03689.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Invasive fungal infections caused by rare filamentous fungi constitute a significant cause of morbidity and mortality in patients with defective immune responses. Despite the advent of new antifungal agents, the problem is escalating as the number of susceptible hosts increases and virulent, more resistant fungal strains emerge. There is evidence that reconstitution of the host immune function is a major contributor to the resolution of these infections. Therapeutic modalities aimed at increasing phagocyte numbers, such as granulocyte transfusions, stimulating the immune response, such as administration of haematopoietic growth factors and other proinflammatory cytokines, or indirectly augmenting immune function have shown promising results in the preclinical setting. Because of the rarity of the infections, multicentre clinical trials are needed to demonstrate the efficacy and safety of the new immunomodulating approaches.
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Affiliation(s)
- A Katragkou
- Infectious Diseases Unit, 3rd Department of Paediatrics, Aristotle University School of Medicine, Hippokration Hospital, Thessaloniki, Greece
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165
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Spellberg B, Ibrahim AS, Chin-Hong PV, Kontoyiannis DP, Morris MI, Perfect JR, Fredricks D, Brass EP. The Deferasirox-AmBisome Therapy for Mucormycosis (DEFEAT Mucor) study: a randomized, double-blinded, placebo-controlled trial. J Antimicrob Chemother 2011; 67:715-22. [PMID: 21937481 DOI: 10.1093/jac/dkr375] [Citation(s) in RCA: 204] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
OBJECTIVES Host iron availability is fundamental to mucormycosis pathogenesis. The combination of liposomal amphotericin B (LAmB) and deferasirox iron chelation therapy synergistically improved survival in diabetic mice with mucormycosis. To determine the safety of combination deferasirox plus LAmB therapy for mucormycosis, a multicentred, placebo-controlled, double-blinded clinical trial was conducted. METHODS Twenty patients with proven or probable mucormycosis were randomized to receive treatment with LAmB plus deferasirox (20 mg/kg/day for 14 days) or LAmB plus placebo (NCT00419770, clinicaltrials.gov). The primary analyses were for safety and exploratory efficacy. RESULTS Patients in the deferasirox arm (n=11) were more likely than those in the placebo arm (n=9) to have active malignancy, neutropenia and corticosteroid therapy, and were less likely to receive concurrent non-study antifungal therapy. Reported adverse events and serious adverse events were similar between the groups. However, death was more frequent in the deferasirox than in the placebo arm at 30 days (45% versus 11%, P=0.1) and 90 days (82% versus 22%, P=0.01). Global success (alive, clinically stable, radiographically improved) for the deferasirox arm versus the placebo arm at 30 and 90 days, respectively, was 18% (2/11) versus 67% (6/9) (P=0.06) and 18% (2/11) versus 56% (5/9) (P=0.2). CONCLUSIONS Patients with mucormycosis treated with deferasirox had a higher mortality rate at 90 days. Population imbalances in this small Phase II study make generalizable conclusions difficult. Nevertheless, these data do not support a role for initial, adjunctive deferasirox therapy for mucormycosis.
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Affiliation(s)
- Brad Spellberg
- Division of General Internal Medicine, Los Angeles Biomedical Research Institute, Harbor-University of California Los Angeles (UCLA) Medical Center, Torrance, CA, USA.
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166
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Host cell invasion in mucormycosis: role of iron. Curr Opin Microbiol 2011; 14:406-11. [PMID: 21807554 DOI: 10.1016/j.mib.2011.07.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2011] [Revised: 06/10/2011] [Accepted: 07/01/2011] [Indexed: 11/24/2022]
Abstract
Clinical hallmarks of mucormycosis infections include the unique susceptibility of patients with increased available serum iron, the propensity of the organism to invade blood vessels, and defective phagocytic function. These hallmarks underscore the crucial roles of iron metabolism, phagocyte function, and interactions with endothelial cells lining blood vessels, in the organism's virulence strategy. In an attempt to understand how Mucorales invade the host, we will review the current knowledge about interactions between Mucorales and the host while evading phagocyte-mediated killing. Additionally, since iron is an important determinant of the disease, we will focus on the role of iron on these interactions. Ultimately, a superior understanding of the pathogenesis of mucormycosis will enable development of novel therapies for this disease.
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167
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Abstract
In recent years, substantial advances have been achieved in the treatment of mucormycosis. It is now clear that early initiation of therapy results in substantially better outcomes, underscoring the need to maintain a high index of suspicion and aggressively biopsy potential lesions. Increasing data support the need for surgical excision of infected and/or necrosed tissue whenever feasible. Based on their superior safety and efficacy, lipid formulations of amphotericin B have become the standard treatment for mucormycosis. Posaconazole may be useful as salvage therapy, but cannot be recommended as primary therapy for mucormycosis based on available data. Pre-clinical and limited retrospective clinical data suggest that combination therapy with lipid formulations of amphotericin and an echinocandin improves survival during mucormycosis. A definitive trial is needed to confirm these results. The use of the iron chelator, deferasirox, as adjunctive therapy also improved outcomes in animal models of mucormycosis. However, its efficacy was not confirmed in a recent, phase 2 clinical trial. Additional study is required of the potential for abrogation of iron acquisition as adjunctive treatment of mucormycosis. Combination polyene-posaconazole therapy was of no benefit in pre-clinical studies. Adjunctive therapy with recombinant cytokines, hyperbaric oxygen, and/or granulocyte transfusions can be considered in selected patients. Large-scale, prospective, randomized clinical trials are needed to define optimal management strategies for mucormycosis.
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168
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Busca A, Limerutti G, Locatelli F, Barbui A, De Rosa FG, Falda M. The reversed halo sign as the initial radiographic sign of pulmonary zygomycosis. Infection 2011; 40:77-80. [DOI: 10.1007/s15010-011-0156-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 06/16/2011] [Indexed: 12/16/2022]
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169
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170
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Sun HY, Singh N. Mucormycosis: its contemporary face and management strategies. THE LANCET. INFECTIOUS DISEASES 2011; 11:301-11. [PMID: 21453871 DOI: 10.1016/s1473-3099(10)70316-9] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Several countries have seen rising frequencies of mucormycosis among patients with haematological disorders, malignancies, or diabetes mellitus, and among transplant recipients. Growing numbers of immunocompromised hosts, widespread use of antifungal agents inactive against mucormycosis, or other unidentified factors, could be contributing to this situation. The predominant clinical manifestations of mucormycosis vary from host to host. Additionally, risk factors specific to different subgroups have been identified, such as leukaemia, allogeneic haemopoietic stem-cell transplant, voriconazole prophylaxis, diabetes, and malnutrition. We summarise the current state of knowledge of characteristics and risk factors and discuss topical developments in therapeutic methods and strategies in the management of mucormycosis.
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Affiliation(s)
- Hsin-Yun Sun
- Infectious Diseases Section, VA Pittsburgh Healthcare System, Pittsburgh, PA 15240, USA
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171
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Kanda J, Kawabata H, Chao NJ. Iron overload and allogeneic hematopoietic stem-cell transplantation. Expert Rev Hematol 2011; 4:71-80. [PMID: 21322780 DOI: 10.1586/ehm.10.81] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Iron overload is frequently observed in patients with hematologic diseases before and after allogeneic stem-cell transplantation because they usually receive multiple red blood cell transfusions. Elevated pretransplant serum ferritin levels, which are widely used as indicators of body iron status, are significantly associated with a lower overall survival rate and a higher incidence of treatment-related complications; for example, infections and hepatic veno-occlusive disease. As serum ferritin levels are affected, not only by iron loading but also by inflammation, imaging techniques to quantify tissue iron levels have been developed, for example, quantitative MRI using the transverse magnetic relaxation rate, and superconducting quantum interference devices. Iron chelators, such as deferasirox, a new oral iron-chelating agent, reduce iron load in transfusion-dependent patients. Iron-chelating therapy before and/or after transplantation is a promising strategy to improve the clinical outcomes of transplant patients with iron overload. However, further research is needed to prove the direct relationship between iron overload and adverse outcomes, as well as to determine the effects of treatment for iron overload on outcomes of allogeneic stem-cell transplantation.
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Affiliation(s)
- Junya Kanda
- Division of Cellular Therapy, Department of Medicine, Duke University Medical Center, 2400 Pratt Street, Suite 1100, Durham, NC 27705, USA.
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172
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Fungicidal monoclonal antibody C7 interferes with iron acquisition in Candida albicans. Antimicrob Agents Chemother 2011; 55:3156-63. [PMID: 21518848 DOI: 10.1128/aac.00892-10] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
We have developed a monoclonal antibody (MAb), C7, that reacts with the Als3p and enolase present in the Candida albicans cell wall and exerts three anti-Candida activities: candidacidal activity and inhibition of both adhesion and filamentation. To investigate the mode of action of MAb C7 on fungal viability, we examined changes in the genome-wide gene expression profile of C. albicans grown in the presence of a subinhibitory concentration of MAb C7 (12.5 μg/ml) by using microarrays. A total of 49 genes were found to be differentially expressed upon treatment with MAb C7. Of these, 28 were found to be upregulated and 21 were found to be downregulated. The categories of upregulated genes with the largest number of variations were those involved in iron uptake or related to iron homeostasis (42.86%), while the energy-related group accounted for 38.10% of the downregulated genes (8/21). Results were validated by real-time PCR. Since these effects resembled those found under iron-limited conditions, the activity of MAb C7 on C. albicans mutants with deletions in key genes implicated in the three iron acquisition systems described in this yeast was also assessed. Only mutants lacking the TPK1 gene and, to a lesser extent, the TPK2 gene were less sensitive to the candidacidal effect of MAb C7. FeCl(3) or hemin at concentrations of ≥ 7.8 μM reversed the candidacidal effect of MAb C7 on C. albicans in a concentration-dependent manner. The results presented in this study provide evidence that the candidacidal effect of MAb C7 is related to the blockage of the reductive iron uptake pathway of C. albicans.
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173
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Neupane GP, Kim DM. Comparison of the effects of deferasirox, deferiprone, and deferoxamine on the growth and virulence of Vibrio vulnificus. Transfusion 2011; 49:1762-9. [PMID: 19413741 DOI: 10.1111/j.1537-2995.2009.02186.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Since deferoxamine (DFO), a standard iron-chelating agent that is widely used in patients with iron overload such as hemochromatosis or thalassemia, is a kind of hydroxamine siderophore of Streptomyces species, it can accelerate the in vitro growth of ferophilic organisms such as Vibrio vulnificus, Yersinia enterocolitica, and Mucorales. STUDY DESIGN AND METHODS We compared the effects of the two oral iron chelators, deferiprone (DFP) and deferasirox (DFS), on the growth and virulence of V. vulnificus with that of the parenteral iron-chelating drug DFO used to treat patients with iron overload. RESULTS When V. vulnificus ATCC 27562 was grown in iron-poor liquid medium with α,α′-dipryridyl, addition of DFO promoted its growth, whereas DFP and DFS did not. Only DFP and DFS showed growth inhibitory effect by chelating iron and causing iron deprivation. Similarly, on iron-poor agar plates, various clinical V. vulnificus strains were only able to grow around filter paper disks impregnated with DFO. Our in vitro study data showed that DFS or DFP has more potential clinical application for preventing V. vulnificus infection in patients receiving iron chelation therapy. CONCLUSIONS When patients with iron overload need iron chelation therapy, especially in a population at high risk for V. vulnificus in its endemic season, DFS or DFP may be safely used rather than DFO.
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Affiliation(s)
- Ganesh Prasad Neupane
- Division of Infectious Diseases, Department of Internal Medicine, Research Center for Resistant Cells, Chosun University School of Medicine, Gwangju, Republic of Korea
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174
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Almyroudis NG, Segal BH. Antifungal prophylaxis and therapy in patients with hematological malignancies and hematopoietic stem cell transplant recipients. Expert Rev Anti Infect Ther 2011; 8:1451-66. [PMID: 21133669 DOI: 10.1586/eri.10.141] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Patients with acute leukemia and hematopoietic stem cell transplant recipients are at risk of a spectrum of invasive fungal diseases corresponding to the type and intensity of immunosuppression. The development of newer antifungal agents has broadened therapeutic options. In the 1990s, lipid formulations of amphotericin B became widely used as safer alternatives to amphotericin B deoxycholate. In addition, fluconazole was shown to be beneficial as a yeast-active prophylaxis in hematopoietic stem cell transplant recipients. In the past decade, the antifungal armamentarium was further enhanced with the availability of extended-spectrum azoles and echinocandins. The development of effective broad-spectrum antifungal agents has led to their use as prophylaxis rather than delaying treatment until clinical signs of infection manifest. Antigen-based and PCR-based diagnostic adjuncts facilitate earlier detection of invasive fungal diseases compared with conventional culture, and have been incorporated into strategies in which initiation or modification of an antifungal regimen is targeted to patients with the highest likelihood of having fungal disease. Here, we review the pharmacological data and major clinical trials that guide the use of antifungals, as well as areas of uncertainty and future perspectives.
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175
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Abstract
The fungal kingdom is vast, spanning ~1.5 to as many as 5 million species diverse as unicellular yeasts, filamentous fungi, mushrooms, lichens, and both plant and animal pathogens. The fungi are closely aligned with animals in one of the six to eight supergroups of eukaryotes, the opisthokonts. The animal and fungal kingdoms last shared a common ancestor ~1 billion years ago, more recently than other groups of eukaryotes. As a consequence of their close evolutionary history and shared cellular machinery with metazoans, fungi are exceptional models for mammalian biology, but prove more difficult to treat in infected animals. The last common ancestor to the fungal/metazoan lineages is thought to have been unicellular, aquatic, and motile with a posterior flagellum, and certain extant species closely resemble this hypothesized ancestor. Species within the fungal kingdom were traditionally assigned to four phyla, including the basal fungi (Chytridiomycota, Zygomycota) and the more recently derived monophyletic lineage, the dikarya (Ascomycota, Basidiomycota). The fungal tree of life project has revealed that the basal lineages are polyphyletic, and thus there are as many as eight to ten fungal phyla. Fungi that infect vertebrates are found in all of the major lineages, and virulence arose multiple times independently. A sobering recent development involves the species Batrachochytrium dendrobatidis from the basal fungal phylum, the Chytridiomycota, which has emerged to cause global amphibian declines and extinctions. Genomics is revolutionizing our view of the fungal kingdom, and genome sequences for zygomycete pathogens (Rhizopus, Mucor), skin-associated fungi (dermatophytes, Malassezia), and the Candida pathogenic species clade promise to provide insights into the origins of virulence. Here we survey the diversity of fungal pathogens and illustrate key principles revealed by genomics involving sexual reproduction and sex determination, loss of conserved pathways in derived fungal lineages that are retained in basal fungi, and shared and divergent virulence strategies of successful human pathogens, including dimorphic and trimorphic transitions in form. The overarching conclusion is that fungal pathogens of animals have arisen repeatedly and independently throughout the fungal tree of life, and while they share general properties, there are also unique features to the virulence strategies of each successful microbial pathogen.
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Affiliation(s)
- Joseph Heitman
- Department of Molecular Genetics and Microbiology Duke University Medical Center
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176
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Combination therapy of murine mucormycosis or aspergillosis with iron chelation, polyenes, and echinocandins. Antimicrob Agents Chemother 2011; 55:1768-70. [PMID: 21263057 DOI: 10.1128/aac.01577-10] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Liposomal amphotericin B (LAmB) combined wither either micafungin or deferasirox was synergistic in previous murine studies with mucormycosis or aspergillosis. We hypothesized that triple therapy using LAmB, micafungin, and deferasirox could further improve outcomes of mucormycosis or aspergillosis. Triple therapy improved survival and reduced tissue fungal burden of mice with mucormycosis and to a lesser extent with aspergillosis. Continued investigation into the use of triple therapy against mucormycosis and aspergillosis is warranted.
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177
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178
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Candida albicans Hap43 is a repressor induced under low-iron conditions and is essential for iron-responsive transcriptional regulation and virulence. EUKARYOTIC CELL 2010; 10:207-25. [PMID: 21131439 DOI: 10.1128/ec.00158-10] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Candida albicans is an opportunistic fungal pathogen that exists as normal flora in healthy human bodies but causes life-threatening infections in immunocompromised patients. In addition to innate and adaptive immunities, hosts also resist microbial infections by developing a mechanism of "natural resistance" that maintains a low level of free iron to restrict the growth of invading pathogens. C. albicans must overcome this iron-deprived environment to cause infections. There are three types of iron-responsive transcriptional regulators in fungi; Aft1/Aft2 activators in yeast, GATA-type repressors in many fungi, and HapX/Php4 in Schizosaccharomyces pombe and Aspergillus species. In this study, we characterized the iron-responsive regulator Hap43, which is the C. albicans homolog of HapX/Php4 and is repressed by the GATA-type repressor Sfu1 under iron-sufficient conditions. We provide evidence that Hap43 is essential for the growth of C. albicans under low-iron conditions and for C. albicans virulence in a mouse model of infection. Hap43 was not required for iron acquisition under low-iron conditions. Instead, it was responsible for repression of genes that encode iron-dependent proteins involved in mitochondrial respiration and iron-sulfur cluster assembly. We also demonstrated that Hap43 executes its function by becoming a transcriptional repressor and accumulating in the nucleus in response to iron deprivation. Finally, we found a connection between Hap43 and the global corepressor Tup1 in low-iron-induced flavinogenesis. Taken together, our data suggest a complex interplay among Hap43, Sfu1, and Tup1 to coordinately regulate iron acquisition, iron utilization, and other iron-responsive metabolic activities.
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179
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León GA, Herazo JG. Zigomicosis. INFECTIO 2010. [DOI: 10.1016/s0123-9392(10)70135-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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180
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Nairz M, Schroll A, Sonnweber T, Weiss G. The struggle for iron - a metal at the host-pathogen interface. Cell Microbiol 2010; 12:1691-702. [DOI: 10.1111/j.1462-5822.2010.01529.x] [Citation(s) in RCA: 283] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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181
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Activity of deferasirox in Mucorales: influences of species and exogenous iron. Antimicrob Agents Chemother 2010; 55:411-3. [PMID: 20956598 DOI: 10.1128/aac.00792-10] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Differences in deferasirox susceptibility among members of the order Mucorales are unknown. Here we show that Cunninghamella bertholletiae (four isolates) and Mucor species (five isolates) display higher deferasirox MICs and minimal fungicidal concentrations compared to Rhizopus species (six isolates). Exogenous iron further attenuated the deferasirox susceptibility of Mucorales isolates with low MICs. Vital staining revealed damage to subapical compartments in susceptible strains.
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182
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Unal S, Kuskonmaz B, Hazirolan T, Eldem G, Aytac S, Cetin M, Uckan D, Gumruk F. Deferasirox use after hematopoietic stem cell transplantation in pediatric patients with beta-thalassemia major: preliminary results. Pediatr Hematol Oncol 2010; 27:482-9. [PMID: 20615065 DOI: 10.3109/08880018.2010.493573] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
There are limited data on the posttransplantation pharmacological treatment of iron overload in ex-thalassemic patients and the current approach is phlebotomy. The authors chelated 2 ex-thalassemic patients after hematopoietic stem cell transplantation with deferasirox for 6 and 24 months. Although serum ferritin levels decreased, cardiac and hepatic iron load, measured by T2* magnetic resonance imaging (MRI), showed decrease in iron overload in these organs. The drug was tolerated well by both patients and no adverse effect on donor hematopoiesis was observed. This preliminary study demonstrates that deferasirox is well tolerated in these patients and will be a good potential therapy when more data have been obtained from larger studies.
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Affiliation(s)
- Sule Unal
- Division of Pediatric Hematology, Hacettepe University, Ankara, Turkey.
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183
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Abstract
Serious infections due to non-Aspergillus molds are being encountered with increasing frequency. Factors likely responsible for the rise of these infections include aging populations in countries with advanced medical technologies, the resultant increase in incidence of many cancers, increasingly intensive myeloablative therapies for these cancers, increasingly intensive care for critically ill patients, and increases in the frequency of solid organ and hematopoietic stem cell transplantation. Although diagnostic and therapeutic modalities have improved, mortality rates for invasive mold infections remain high. In this review, we summarize current knowledge about non-Aspergillus mold infections of the chest, with a focus on risk factors, clinical features, diagnosis, and treatment.
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184
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Intra-abdominal Rhizopus microsporus infection successfully treated by combined aggressive surgical, antifungal, and iron chelating therapy. J Pediatr Hematol Oncol 2010; 32:e238-40. [PMID: 20661158 DOI: 10.1097/mph.0b013e3181e622bf] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Zygomycetes are widely distributed in the environment as inhabitants of soil and decaying matter. On rare occasions, these organisms can cause invasive infections in immunocompromised hosts. As zygomycetes are resistant to most conventional antifungal agents, its infection is often fatal. We report 2 cases of unusual intra-abdominal Rhizopus microsporus infection in children with acute leukemia as a result of an unprecedented outbreak due to oral intake of contaminated allopurinol tablets and ready-to-eat food items. Among the 2 patients, one of them survived after aggressive combined surgical, antifungal (AmBisome, Caspofungin, and Posaconazole) and iron chelation therapy.
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185
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Successful treatment of periodontal mucormycosis: report of a case and literature review. ACTA ACUST UNITED AC 2010; 109:e64-9. [PMID: 20219588 DOI: 10.1016/j.tripleo.2009.11.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 10/29/2009] [Accepted: 11/03/2009] [Indexed: 11/23/2022]
Abstract
Mucormycosis is an aggressive and potentially devastating fungal infection which typically manifests in pulmonary, rhinocerebral, or disseminated forms in patients with hematologic malignancy. Mucormycosis confined to the periodontium is uncommon, and to our knowledge only 6 cases have been reported in the English-language literature. This case report describes a patient with acute leukemia and periodontal mucormycosis. Calcofluor fluorescence microscopy is also proposed as a method for establishing a prompt diagnosis and guiding extent of intraoperative surgical debridement.
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186
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Iron chelation therapy in myelodysplastic syndromes. Adv Hematol 2010; 2010:756289. [PMID: 20672005 PMCID: PMC2905902 DOI: 10.1155/2010/756289] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 01/18/2010] [Accepted: 04/20/2010] [Indexed: 01/19/2023] Open
Abstract
Myelodysplastic syndromes (MDS) are a heterogeneous disorder of the hematopoietic stem cells, frequently characterized by anemia and transfusion dependency. In low-risk patients, transfusion dependency can be long lasting, leading to iron overload. Iron chelation therapy may be a therapeutic option for these patients, especially since the approval of oral iron chelators, which are easier to use and better accepted by the patients. The usefulness of iron chelation in MDS patients is still under debate, mainly because of the lack of solid prospective clinical trials that should take place in the future. This review aims to summarize what is currently known about the incidence and clinical consequences of iron overload in MDS patients and the state-of the-art of iron chelation therapy in this setting. We also give an overview of clinical guidelines for chelation in MDS published to date and some perspectives for the future.
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187
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Kontoghiorghes GJ, Kolnagou A, Skiada A, Petrikkos G. The Role of Iron and Chelators on Infections in Iron Overload and Non Iron Loaded Conditions: Prospects for the Design of New Antimicrobial Therapies. Hemoglobin 2010; 34:227-39. [DOI: 10.3109/03630269.2010.483662] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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188
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Liu M, Spellberg B, Phan QT, Fu Y, Fu Y, Lee AS, Edwards JE, Filler SG, Ibrahim AS. The endothelial cell receptor GRP78 is required for mucormycosis pathogenesis in diabetic mice. J Clin Invest 2010; 120:1914-24. [PMID: 20484814 PMCID: PMC2877958 DOI: 10.1172/jci42164] [Citation(s) in RCA: 206] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Accepted: 03/24/2010] [Indexed: 02/06/2023] Open
Abstract
Mucormycosis is a fungal infection of the sinuses, brain, or lungs that causes a mortality rate of at least 50% despite first-line therapy. Because angioinvasion is a hallmark of mucormycosis infections, we sought to define the endothelial cell receptor(s) for fungi of the order Mucorales (the fungi that cause mucormycosis). Furthermore, since patients with elevated available serum iron, including those with diabetic ketoacidosis (DKA), are uniquely susceptible to mucormycosis, we sought to define the role of iron and glucose in regulating the expression of such a receptor. Here, we have identified glucose-regulated protein 78 (GRP78) as what we believe to be a novel host receptor that mediates invasion and damage of human endothelial cells by Rhizopus oryzae, the most common etiologic species of Mucorales, but not Candida albicans or Aspergillus fumigatus. Elevated concentrations of glucose and iron, consistent with those seen during DKA, enhanced GRP78 expression and the resulting R. oryzae invasion and damage of endothelial cells in a receptor-dependent manner. Mice with DKA, which have enhanced susceptibility to mucormycosis, exhibited increased expression of GRP78 in sinus, lungs, and brain compared with normal mice. Finally, GRP78-specific immune serum protected mice with DKA from mucormycosis. These results suggest a unique susceptibility of patients with DKA to mucormycosis and provide a foundation for the development of new therapeutic interventions for these deadly infections.
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Affiliation(s)
- Mingfu Liu
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and
Division of General Internal Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Brad Spellberg
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and
Division of General Internal Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Quynh T. Phan
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and
Division of General Internal Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Yue Fu
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and
Division of General Internal Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Yong Fu
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and
Division of General Internal Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Amy S. Lee
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and
Division of General Internal Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - John E. Edwards
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and
Division of General Internal Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Scott G. Filler
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and
Division of General Internal Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Ashraf S. Ibrahim
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and
Division of General Internal Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
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189
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Ibrahim AS, Gebremariam T, Lin L, Luo G, Husseiny MI, Skory CD, Fu Y, French SW, Edwards JE, Spellberg B. The high affinity iron permease is a key virulence factor required for Rhizopus oryzae pathogenesis. Mol Microbiol 2010; 77:587-604. [PMID: 20545847 DOI: 10.1111/j.1365-2958.2010.07234.x] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Rhizopus oryzae is the most common cause of mucormycosis, an angioinvasive fungal infection that causes more then 50% mortality rate despite first-line therapy. Clinical and animal model data clearly demonstrate that the presence of elevated available serum iron predisposes the host to mucormycosis. The high affinity iron permease gene (FTR1) is required for R. oryzae iron transport in iron-depleted environments. Here we demonstrate that FTR1 is required for full virulence of R. oryzae in mice. We show that FTR1 is expressed during infection in diabetic ketoacidosis (DKA) mice. In addition, we disrupted FTR1 by double cross-over homologous recombination, but multinucleated R. oryzae could not be forced to segregate to a homokaryotic null allele. Nevertheless, a reduction of the relative copy number of FTR1 and inhibition of FTR1 expression by RNAi compromised the ability of R. oryzae to acquire iron in vitro and reduced its virulence in DKA mice. Importantly, passive immunization with anti-Ftr1p immune sera protected DKA mice from infection with R. oryzae. Thus, FTR1 is a virulence factor for R. oryzae, and anti-Ftr1p passive immunotherapy deserves further evaluation as a strategy to improve outcomes of deadly mucormycosis.
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Affiliation(s)
- Ashraf S Ibrahim
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-University of California Los Angeles (UCLA) Medical Center, Torrance, CA, USA.
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190
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Gruber I, Lackinger B. Verlaufsbeobachtung einer rhinozerebralen Zygomykose bei einem nur teilweise complianten Patienten. SPEKTRUM DER AUGENHEILKUNDE 2010. [DOI: 10.1007/s00717-010-0400-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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191
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Manzoori JL, Jouyban A, Amjadi M, Panahi-Azar V, Tamizi E, Vaez-Gharamaleki J. Terbium-sensitized fluorescence method for the determination of deferasirox in biological fluids and tablet formulation. LUMINESCENCE 2010; 26:244-50. [DOI: 10.1002/bio.1218] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 04/04/2010] [Accepted: 04/13/2010] [Indexed: 10/19/2022]
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192
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193
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Abstract
We report three cases of ileocolic mucormycosis in adult immunocompromised patients presenting as acute abdomen. All patients underwent laparotomy but two of them died from multiorgan failure before the diagnoses were confirmed. The diagnosis of gastrointestinal mucormycosis is rarely suspected, and antemortem diagnosis is made in only 25%-50% of cases. These cases illustrate the difficulty encountered by surgeons in managing acute abdomen in neutropenic patients with hematological malignancy. The management of colonic mucormycosis in the published literature is also reviewed.
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194
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Busca A, Falda M, Manzini P, D'Antico S, Valfrè A, Locatelli F, Calabrese R, Chiappella A, D'Ardia S, Longo F, Piga A. Iron Overload in Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation: Quantification of Iron Burden by a Superconducting Quantum Interference Device (SQUID) and Therapeutic Effectiveness of Phlebotomy. Biol Blood Marrow Transplant 2010; 16:115-22. [DOI: 10.1016/j.bbmt.2009.09.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Accepted: 09/16/2009] [Indexed: 10/20/2022]
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195
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Mitchell TG, Verweij P, Hoepelman AI. Opportunistic and systemic fungi. Infect Dis (Lond) 2010. [DOI: 10.1016/b978-0-323-04579-7.00178-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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196
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Ibrahim AS, Gebremariam T, French SW, Edwards JE, Spellberg B. The iron chelator deferasirox enhances liposomal amphotericin B efficacy in treating murine invasive pulmonary aspergillosis. J Antimicrob Chemother 2009; 65:289-92. [PMID: 19942619 DOI: 10.1093/jac/dkp426] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Increased bone marrow iron levels in patients with haematological malignancies is an independent risk factor for developing invasive pulmonary aspergillosis (IPA), suggesting an important role for iron uptake in the pathogenesis of IPA. We sought to determine the potential for combination therapy with the iron chelator deferasirox + liposomal amphotericin B (LAmB) to improve the outcome of murine IPA compared with LAmB monotherapy. METHODS In vitro MIC and minimum fungicidal concentration (MFC) values of the iron chelator, deferasirox, for Aspergillus fumigatus were determined by microdilution assay. In addition, we studied the efficacy of deferasirox alone or combined with LAmB in treating immunocompromised mice infected with A. fumigatus via inhalation. RESULTS Deferasirox was cidal in vitro against A. fumigatus, with an MIC and MFC of 25 and 50 mg/L, respectively. Deferasirox monotherapy modestly prolonged survival of mice with IPA. Combination deferasirox + LAmB therapy synergistically improved survival and reduced lung fungal burden compared with either monotherapy alone. CONCLUSIONS Iron chelation therapy with deferasirox alone or in combination with LAmB is effective in treating experimental IPA. Further study of deferasirox is warranted as adjunctive therapy for IPA infections.
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Affiliation(s)
- Ashraf S Ibrahim
- Los Angeles Biomedical Research Institute at Harbor-University of California Los Angeles Medical Center, Torrance, CA 90502, USA.
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197
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Adachi JA, Kontoyiannis DP. Gastrointestinal Mucormycosis: An Elusive, Unusual, and Severe Opportunistic Mycosis. Gastroenterol Hepatol (N Y) 2009; 5:661-662. [PMID: 37967456 PMCID: PMC2886422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Affiliation(s)
- Javier A Adachi
- The University of Texas-M. D. Anderson Cancer Center, Houston, Texas
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198
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Shoham S, Roilides E, Walsh TJ. Augmentation of innate host defenses against opportunistic fungal pathogens. CURRENT FUNGAL INFECTION REPORTS 2009. [DOI: 10.1007/s12281-009-0024-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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199
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Absence of functional Hfe protects mice from invasive Salmonella enterica serovar Typhimurium infection via induction of lipocalin-2. Blood 2009; 114:3642-51. [PMID: 19700664 DOI: 10.1182/blood-2009-05-223354] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mutations of HFE are associated with hereditary hemochromatosis, but their influence on host susceptibility to infection is incompletely understood. We report that mice lacking one or both Hfe alleles are protected from septicemia with Salmonella Typhimurium, displaying prolonged survival and improved control of bacterial replication. This increased resistance is paralleled by an enhanced production of the enterochelin-binding peptide lipocalin-2 (Lcn2), which reduces the availability of iron for Salmonella within Hfe-deficient macrophages. Accordingly, Hfe(-/-)Lcn2(-/-) macrophages are unable to efficiently control the infection or to withhold iron from intracellular Salmonella. Correspondingly, the protection conferred by the Hfe defect is abolished in Hfe(-/-) mice infected with enterochelin-deficient Salmonella as well as in Hfe(-/-)Lcn2(-/-) mice infected with wild-type bacteria. Thus, by induction of the iron-capturing peptide Lcn2, absence of functional Hfe confers host resistance to systemic infection with Salmonella, thereby providing an evolutionary advantage which may account for the high prevalence of genetic hemochromatosis.
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200
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Naggie S, Perfect JR. Molds: hyalohyphomycosis, phaeohyphomycosis, and zygomycosis. Clin Chest Med 2009; 30:337-53, vii-viii. [PMID: 19375639 DOI: 10.1016/j.ccm.2009.02.009] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Emerging fungi previously thought to be nonpathogenic are now recognized as playing a significant role in the increased incidence of invasive fungal disease. This change in the epidemiology of invasive fungal infections (IFIs) has occurred in the era of aggressive new therapies for hematopoietic stem cell transplantation and other malignancies that lead to profound immunosuppression for longer durations and has extended the survival of these critically ill patients. The significant morbidity and mortality associated with these infections is not only related to the host populations but to delayed recognition and diagnosis and high rates of resistance in some of these emerging pathogens to standard antifungal therapies.
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Affiliation(s)
- Susanna Naggie
- Division of Infectious Diseases, Department of Internal Medicine, Duke University Medical Center, Durham, NC 27710, USA.
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