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Garnacho-Montero J, Barrero-García I, León-Moya C. Fungal infections in immunocompromised critically ill patients. JOURNAL OF INTENSIVE MEDICINE 2024; 4:299-306. [PMID: 39035612 PMCID: PMC11258510 DOI: 10.1016/j.jointm.2024.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/01/2024] [Accepted: 01/02/2024] [Indexed: 07/23/2024]
Abstract
Diverse pathogenic fungi can produce severe infections in immunocompromised patients, thereby justifying intensive care unit (ICU) admissions. In some cases, the infections can develop in immunocompromised patients who were previously admitted to the ICU. Aspergillus spp., Pneumocystis jirovecii, Candida spp., and Mucorales are the fungi that are most frequently involved in these infections. Diagnosis continues to be challenging because symptoms and signs are unspecific. Herein, we provide an in-depth review about the diagnosis, with emphasis on recent advances, and treatment of these invasive fungal infections in the ICU setting.
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Affiliation(s)
- José Garnacho-Montero
- Unidad Clínica de Cuidados Intensivos, Hospital Universitario Virgen Macarena, Sevilla, Spain
| | - Irene Barrero-García
- Unidad Clínica de Cuidados Intensivos, Hospital Universitario Virgen Macarena, Sevilla, Spain
| | - Cristina León-Moya
- Unidad Clínica de Cuidados Intensivos, Hospital Universitario Virgen Macarena, Sevilla, Spain
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Desoubeaux G, Lemaignen A, Alanio A, Ehrmann S. Re: 'Which trial do we need? Combination treatment of Pneumocystis jirovecii pneumonia in non-HIV infected patients' by Cornely et al. Clin Microbiol Infect 2023; 29:1455-1456. [PMID: 37321395 DOI: 10.1016/j.cmi.2023.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 06/06/2023] [Indexed: 06/17/2023]
Affiliation(s)
- Guillaume Desoubeaux
- CHRU de Tours, Parasitologie - Mycologie - Médecine tropicale, Tours, France; Université de Tours, INSERM U1100, Centre d'étude des pathologies respiratoires, Tours, France.
| | - Adrien Lemaignen
- CHRU de Tours, Maladies Infectieuses et tropicales, Tours, France
| | - Alexandre Alanio
- CHU Saint-Louis, Laboratoire de Parasitologie - Mycologie, Paris, France; Institut Pasteur, Centre-National de référence des mycoses et antifongiques, Paris, France
| | - Stephan Ehrmann
- Université de Tours, INSERM U1100, Centre d'étude des pathologies respiratoires, Tours, France; CHRU de Tours, Médecine Intensive Réanimation, CIC INSERM 1415, CRICS-TriggerSep Network, Tours, France
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Qi H, Dong D, Liu N, Xu Y, Qi M, Gu Q. Efficacy of initial caspofungin plus trimethoprim/sulfamethoxazole for severe PCP in patients without human immunodeficiency virus infection. BMC Infect Dis 2023; 23:409. [PMID: 37328748 PMCID: PMC10273704 DOI: 10.1186/s12879-023-08372-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 06/03/2023] [Indexed: 06/18/2023] Open
Abstract
BACKGROUND The number of pneumocystis pneumonia (PCP) cases is increasing in immunocompromised patients without human immunodeficiency virus infection (HIV), causing serious morbidity with high mortality. Trimethoprim/sulfamethoxazole (TMP/SMZ) monotherapy has limited effectiveness in the treatment of PCP. Clinical data on whether initial caspofungin plus TMP/SMZ for this disease is superior to monotherapy in non-HIV-infected patients are limited. We aimed to compare the clinical effectiveness of these regimens for severe PCP in non-HIV patients. METHODS A retrospective study reviewed 104 non-HIV-infected patients with confirmed PCP in the intensive care unit between January 2016 and December 2021. Eleven patients were excluded from the study because TMP/SMZ could not be used due to severe hematologic disorders or clinical data were missing. All enrolled patients were divided into three groups according to different treatment strategies: Group 1 received TMP/SMZ monotherapy, Group 2 received caspofungin combined with TMP/SMZ as first-line therapy, and Group 3 initially received TMP/SMZ monotherapy and later received caspofungin as salvage therapy. The clinical characteristics and outcomes were compared among the groups. RESULTS A total of 93 patients met the criteria. The overall positive response rate of anti-PCP treatment was 58.06%, and the overall 90-day all-cause mortality rate was 49.46%. The median APACHE II score was 21.44. The concurrent infection rate was 74.19%, among whom 15.05% (n = 14) of those patients had pulmonary aspergillosis, 21.05% (n = 20) had bacteremia, and 23.65% (n = 22) had CMV infections. The patients who received initial caspofungin combination with TMP/SMZ had the best positive response rate (76.74%) compared to others (p = 0.001). Furthermore, the group that received initial caspofungin combined with TMP/SMZ had a 90-day all-cause mortality rate (39.53%) that was significantly different from that of the shift group (65.51%, p = 0.024), but this rate showed no statistically significant difference compared with that in the monotherapy group (48.62%, p = 0.322). None of the patients had serious adverse events from caspofungin therapy. CONCLUSIONS For non-HIV-infected patients with severe PCP, initial combination therapy with caspofungin and TMP/SMZ is a promising first-line treatment option compared with TMP/SMZ monotherapy and combination therapy as salvage therapy.
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Affiliation(s)
- Hui Qi
- Department of Intensive Care Unit, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, China
| | - Danjiang Dong
- Department of Intensive Care Unit, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, China
| | - Ning Liu
- Department of Intensive Care Unit, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, China
| | - Ying Xu
- Department of Intensive Care Unit, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, China
| | - Mengzhi Qi
- Department of Intensive Care Unit, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, China
| | - Qin Gu
- Department of Intensive Care Unit, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, China.
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Xu Y, Li Z, Ouyang L, Su Y, Wang C. Successful treatment of severe Pneumocystis Jirovecii pneumonia in a diffuse large B-cell lymphoma patient after R-CHOP chemotherapy: A case report. SAGE Open Med Case Rep 2023; 11:2050313X231178050. [PMID: 37325165 PMCID: PMC10265330 DOI: 10.1177/2050313x231178050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 05/09/2023] [Indexed: 06/17/2023] Open
Abstract
R-CHOP chemotherapy has been established as the first-line standard treatment for elderly patients diagnosed with diffuse large B-cell lymphoma. However, an increased risk of Pneumocystis jirovecii pneumonia in diffuse large B-cell lymphoma patients after the rituximab-based chemotherapy has been reported. We describe a case who developed intermittent cough, fever and shortness of breath after five cycles of R-CHOP treatment for diffuse large B-cell lymphoma. A rapid deterioration in patient's respiratory condition prompted us to adopt an aggressive anti- Pneumocystis jirovecii pneumonia strategy that combined the conventional trimethoprim/sulfamethoxazole and another two antimicrobials, caspofungin and clindamycin. This is the first report mentioning the successful treatment of severe Pneumocystis jirovecii pneumonia with a triple-drug regimen in a HIV-uninfected patient. The aim of our report is also to emphasize that early and correct diagnosis of Pneumocystis jirovecii pneumonia in immunocompromised HIV-uninfected patients is very important. Relevant oncologists should be alert to the risk of Pneumocystis jirovecii pneumonia in patients receiving R-CHOP chemotherapy.
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Affiliation(s)
- Yan Xu
- Department of Critical Care Medicine, Guangdong Second Provincial General Hospital, Guangzhou, People’s Republic of China
| | - Zhaolin Li
- Department of Pulmonary and Critical Care Medicine, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Lamei Ouyang
- Department of Critical Care Medicine, Guangdong Second Provincial General Hospital, Guangzhou, People’s Republic of China
| | - Yinqing Su
- Department of Critical Care Medicine, Guangdong Second Provincial General Hospital, Guangzhou, People’s Republic of China
| | - Canmin Wang
- Department of Critical Care Medicine, Guangdong Second Provincial General Hospital, Guangzhou, People’s Republic of China
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Wang M, Zhang Z, Dong X, Zhu B. Targeting β-glucans, vital components of the Pneumocystis cell wall. Front Immunol 2023; 14:1094464. [PMID: 36845149 PMCID: PMC9947646 DOI: 10.3389/fimmu.2023.1094464] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 01/16/2023] [Indexed: 02/11/2023] Open
Abstract
β-glucan is the most abundant polysaccharide in the cell wall of Pneumocystis jirovecii, which has attracted extensive attention because of its unique immunobiological characteristics. β-glucan binds to various cell surface receptors, which produces an inflammatory response and accounts for its immune effects. A deeper comprehension of the processes by Pneumocystis β-glucan recognizes its receptors, activates related signaling pathways, and regulates immunity as required. Such understanding will provide a basis for developing new therapies against Pneumocystis. Herein, we briefly review the structural composition of β-glucans as a vital component of the Pneumocystis cell wall, the host immunity mediated by β-glucans after their recognition, and discuss opportunities for the development of new strategies to combat Pneumocystis.
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Affiliation(s)
- Mengyan Wang
- Department II of Infectious Diseases, Xixi Hospital of Hangzhou, Hangzhou, China,Department of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zhongdong Zhang
- Department II of Infectious Diseases, Xixi Hospital of Hangzhou, Hangzhou, China
| | - Xiaotian Dong
- Department of Clinical Laboratory, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Biao Zhu
- Department of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China,*Correspondence: Biao Zhu,
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Extrapulmonary Pneumocystis jirovecii Infection in an Immunocompromised Patient With Concomitant Cytomegalovirus Reactivation: A Case Report and Literature Review. INFECTIOUS DISEASES IN CLINICAL PRACTICE 2023. [DOI: 10.1097/ipc.0000000000001181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Guo J, Chen Z, Kong C, Yu B, Wang T, Zhang Y, Liu Y, Zhou J, Qiu T. Meta-analysis of echinocandins combined with trimethoprim-sulfamethoxazole for treatment of Pneumocystis pneumonia. J Chemother 2022:1-7. [PMID: 35815561 DOI: 10.1080/1120009x.2022.2095155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Jiayu Guo
- Department of Organ Transplantation, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Zhongbao Chen
- Department of Organ Transplantation, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Chenyang Kong
- Department of Organ Transplantation, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Bo Yu
- Department of Organ Transplantation, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Tianyu Wang
- Department of Organ Transplantation, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Yalong Zhang
- Department of Organ Transplantation, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Yiting Liu
- Department of Organ Transplantation, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Jiangqiao Zhou
- Department of Organ Transplantation, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Tao Qiu
- Department of Organ Transplantation, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
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Bateman M, Oladele R, Kolls JK. Diagnosing Pneumocystis jirovecii pneumonia: A review of current methods and novel approaches. Med Mycol 2020; 58:1015-1028. [PMID: 32400869 PMCID: PMC7657095 DOI: 10.1093/mmy/myaa024] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 03/13/2020] [Accepted: 05/07/2020] [Indexed: 12/13/2022] Open
Abstract
Pneumocystis jirovecii can cause life-threatening pneumonia in immunocompromised patients. Traditional diagnostic testing has relied on staining and direct visualization of the life-forms in bronchoalveolar lavage fluid. This method has proven insensitive, and invasive procedures may be needed to obtain adequate samples. Molecular methods of detection such as polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), and antibody-antigen assays have been developed in an effort to solve these problems. These techniques are very sensitive and have the potential to detect Pneumocystis life-forms in noninvasive samples such as sputum, oral washes, nasopharyngeal aspirates, and serum. This review evaluates 100 studies that compare use of various diagnostic tests for Pneumocystis jirovecii pneumonia (PCP) in patient samples. Novel diagnostic methods have been widely used in the research setting but have faced barriers to clinical implementation including: interpretation of low fungal burdens, standardization of techniques, integration into resource-poor settings, poor understanding of the impact of host factors, geographic variations in the organism, heterogeneity of studies, and limited clinician recognition of PCP. Addressing these barriers will require identification of phenotypes that progress to PCP and diagnostic cut-offs for colonization, generation of life-form specific markers, comparison of commercial PCR assays, investigation of cost-effective point of care options, evaluation of host factors such as HIV status that may impact diagnosis, and identification of markers of genetic diversity that may be useful in diagnostic panels. Performing high-quality studies and educating physicians will be crucial to improve the rates of diagnosis of PCP and ultimately to improve patient outcomes.
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Affiliation(s)
- Marjorie Bateman
- Center for Translational Research in Infection and Inflammation, Tulane University School of Medicine, New Orleans, LA 70122, USA
| | - Rita Oladele
- Department of Medical Microbiology and Parasitology, College of Medicine, University of Lagos, Nigeria
| | - Jay K Kolls
- Center for Translational Research in Infection and Inflammation, Tulane University School of Medicine, New Orleans, LA 70122, USA
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Scientific rationale for inhaled caspofungin to treat Pneumocystis pneumonia: A therapeutic innovation likely relevant to investigate in a near future…. Int J Infect Dis 2020; 95:464-467. [PMID: 32194238 DOI: 10.1016/j.ijid.2020.03.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 03/10/2020] [Indexed: 01/08/2023] Open
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Chen PY, Yu CJ, Chien JY, Hsueh PR. Anidulafungin as an alternative treatment for Pneumocystis jirovecii pneumonia in patients who cannot tolerate trimethoprim/sulfamethoxazole. Int J Antimicrob Agents 2020; 55:105820. [PMID: 31622654 DOI: 10.1016/j.ijantimicag.2019.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 09/30/2019] [Accepted: 10/05/2019] [Indexed: 10/25/2022]
Abstract
Evidence supporting the use of an echinocandin alone as an alternative agent for the treatment of Pneumocystis jirovecii pneumonia (PCP) is limited and controversial. This retrospective cohort study was conducted at National Taiwan University Hospital from 1 July 2015 to 31 December 2017. Using multivariable Cox regression analyses, the outcomes of patients receiving trimethoprim/sulfamethoxazole (TMP-SMZ) or anidulafungin single therapy as an alternative treatment for PCP were investigated. A total of 207 patients with PCP were screened and 170 patients were included in the final analysis, among whom 134 (78.8%) received TMP-SMZ and 36 (21.2%) received anidulafungin as alternative anti-PCP treatment. Overall 60-day mortality was 34.1% (58/170), and 60-day mortality did not differ significantly between the anidulafungin group (38.9%; 14/36) and the TMP-SMZ group (32.8%; 44/134) (P = 0.554). Age ≥60 years [hazard ratio (HR) = 1.840, 95% confidence interval (CI) 1.039-3.259; P = 0.036] and HIV infection (HR = 0.102, 95% CI 0.013-0.771; P = 0.027) independently predicted 60-day mortality. Patients with lower SpO2/FiO2 ratio (HR = 0.994, 95% CI 0.990-0.998; P = 0.005) showed a higher 60-day mortality. In the Kaplan-Meier survival analysis, anidulafungin as alternative anti-PCP treatment was not correlated with higher mortality (P = 0.605). Using TMP-SMZ or anidulafungin as alternative anti-PCP treatment had similar 60-day mortality. These findings suggest that anidulafungin therapy may be an effective and alternative treatment for PCP in patients who cannot tolerate TMP-SMZ.
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Affiliation(s)
- Po-Yi Chen
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, No. 7 Chung-Shan S. Road, Taipei 100, Taiwan
| | - Chong-Jen Yu
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, No. 7 Chung-Shan S. Road, Taipei 100, Taiwan
| | - Jung-Yien Chien
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, No. 7 Chung-Shan S. Road, Taipei 100, Taiwan.
| | - Po-Ren Hsueh
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, No. 7 Chung-Shan S. Road, Taipei 100, Taiwan; Department of Laboratory Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, No. 7 Chung-Shan S. Road, Taipei 100, Taiwan.
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Koshy R, Chen T. Combination therapy with trimethoprim-sulfamethoxazole and caspofungin in a case of severe pneumocystis pneumonia. IDCases 2019; 15:e00496. [PMID: 30828545 PMCID: PMC6384316 DOI: 10.1016/j.idcr.2019.e00496] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 01/21/2019] [Accepted: 01/21/2019] [Indexed: 01/15/2023] Open
Abstract
Bactrim failure adverse effects. Alternative echinocandin target. Combination echinocandin therapy.
Trimethoprim-sulfamethoxazole (TMP-SMX, co-trimoxazole, or bactrim) has been the standard first-line treatment against Pneumocystis jirovecii pneumonia (PCP) for decades. However, adverse effects and cases of treatment failure have led to a search for alternative agents. We present a case of a 50 year old immune compromised female whose course of PCP did not improve until Caspofungin was added to TMP-SMX.
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Affiliation(s)
- Robin Koshy
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Department of Infectious Disease, United States
| | - Thomas Chen
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Department of Infectious Disease, United States
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Site-Directed Mutagenesis of the 1,3-β-Glucan Synthase Catalytic Subunit of Pneumocystis jirovecii and Susceptibility Assays Suggest Its Sensitivity to Caspofungin. Antimicrob Agents Chemother 2018; 62:AAC.01159-18. [PMID: 30249686 DOI: 10.1128/aac.01159-18] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 09/11/2018] [Indexed: 12/26/2022] Open
Abstract
The echinocandin caspofungin inhibits the catalytic subunit Gsc1 of the enzymatic complex synthesizing 1,3-β-glucan, an essential compound of the fungal wall. Studies with rodents showed that caspofungin is effective against Pneumocystis asci. However, its efficacy against asci of Pneumocystis jirovecii, the species infecting exclusively humans, remains controversial. The aim of this study was to assess the sensitivity to caspofungin of the P. jirovecii Gsc1 subunit, as well as of those of Pneumocystis carinii and Pneumocystis murina infecting, respectively, rats and mice. In the absence of an established in vitro culture method for Pneumocystis species, we used functional complementation of the Saccharomyces cerevisiae gsc1 deletant. In the fungal pathogen Candida albicans, mutations leading to amino acid substitutions in Gsc1 confer resistance to caspofungin. We introduced the corresponding mutations into the Pneumocystis gsc1 genes using site-directed mutagenesis. In spot dilution tests, the sensitivity to caspofungin of the complemented strains decreased with the number of mutations introduced, suggesting that the wild-type enzymes are sensitive. The MICs of caspofungin determined by Etest and YeastOne for strains complemented with Pneumocystis enzymes (respectively, 0.125 and 0.12 μg/ml) were identical to those upon complementation with the enzyme of C. albicans, for which caspofungin presents low MICs. However, they were lower than the MICs upon complementation with the enzyme of the resistant species Candida parapsilosis (0.19 and 0.25 μg/ml). Sensitivity levels of Gsc1 enzymes of the three Pneumocystis species were similar. Our results suggest that P. jirovecii is sensitive to caspofungin during infections, as are P. carinii and P. murina.
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Ma L, Cissé OH, Kovacs JA. A Molecular Window into the Biology and Epidemiology of Pneumocystis spp. Clin Microbiol Rev 2018; 31:e00009-18. [PMID: 29899010 PMCID: PMC6056843 DOI: 10.1128/cmr.00009-18] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Pneumocystis, a unique atypical fungus with an elusive lifestyle, has had an important medical history. It came to prominence as an opportunistic pathogen that not only can cause life-threatening pneumonia in patients with HIV infection and other immunodeficiencies but also can colonize the lungs of healthy individuals from a very early age. The genus Pneumocystis includes a group of closely related but heterogeneous organisms that have a worldwide distribution, have been detected in multiple mammalian species, are highly host species specific, inhabit the lungs almost exclusively, and have never convincingly been cultured in vitro, making Pneumocystis a fascinating but difficult-to-study organism. Improved molecular biologic methodologies have opened a new window into the biology and epidemiology of Pneumocystis. Advances include an improved taxonomic classification, identification of an extremely reduced genome and concomitant inability to metabolize and grow independent of the host lungs, insights into its transmission mode, recognition of its widespread colonization in both immunocompetent and immunodeficient hosts, and utilization of strain variation to study drug resistance, epidemiology, and outbreaks of infection among transplant patients. This review summarizes these advances and also identifies some major questions and challenges that need to be addressed to better understand Pneumocystis biology and its relevance to clinical care.
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Affiliation(s)
- Liang Ma
- Critical Care Medicine Department, NIH Clinical Center, Bethesda, Maryland, USA
| | - Ousmane H Cissé
- Critical Care Medicine Department, NIH Clinical Center, Bethesda, Maryland, USA
| | - Joseph A Kovacs
- Critical Care Medicine Department, NIH Clinical Center, Bethesda, Maryland, USA
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Huang YS, Yang JJ, Lee NY, Chen GJ, Ko WC, Sun HY, Hung CC. Treatment of Pneumocystis jirovecii pneumonia in HIV-infected patients: a review. Expert Rev Anti Infect Ther 2017; 15:873-892. [PMID: 28782390 DOI: 10.1080/14787210.2017.1364991] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Pneumocystis pneumonia is a potentially life-threatening pulmonary infection that occurs in immunocompromised individuals and HIV-infected patients with a low CD4 cell count. Trimethoprim-sulfamethoxazole has been used as the first-line agent for treatment, but mutations within dihydropteroate synthase gene render potential resistance to sulfamide. Despite advances of combination antiretroviral therapy (cART), Pneumocystis pneumonia continues to occur in HIV-infected patients with late presentation for cART or virological and immunological failure after receiving cART. Areas covered: This review summarizes the diagnosis and first-line and alternative treatment and prophylaxis for Pneumocystis pneumonia in HIV-infected patients. Articles for this review were identified through searching PubMed. Search terms included: 'Pneumocystis pneumonia', 'Pneumocystis jirovecii pneumonia', 'Pneumocystis carinii pneumonia', 'trimethoprim-sulfamethoxazole', 'primaquine', 'trimetrexate', 'dapsone', 'pentamidine', 'atovaquone', 'echinocandins', 'human immunodeficiency virus infection', 'acquired immunodeficiency syndrome', 'resistance to sulfamide' and combinations of these terms. We limited the search to English language papers that were published between 1981 and March 2017. We screened all identified articles and cross-referenced studies from retrieved articles. Expert commentary: Trimethoprim-sulfamethoxazole will continue to be the first-line agent for Pneumocystis pneumonia given its cost, availability of both oral and parenteral formulations, and effectiveness or efficacy in both treatment and prophylaxis. Whether resistance due to mutations within dihydropteroate synthase gene compromises treatment effectiveness remains controversial. Continued search for effective alternatives with better safety profiles for Pneumocystis pneumonia is warranted.
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Affiliation(s)
- Yu-Shan Huang
- a Department of Internal Medicine , National Taiwan University Hospital Hsin-Chu Branch , Hsin-Chu , Taiwan
| | - Jen-Jia Yang
- b Department of Internal Medicine , Po Jen General Hospital , Taipei , Taiwan
| | - Nan-Yao Lee
- c Department of Internal Medicine , National Cheng Kung University Hospital , Tainan , Taiwan.,d Department of Medicine , College of Medicine, National Cheng Kung University , Tainan , Taiwan
| | - Guan-Jhou Chen
- e Department of Internal Medicine , National Taiwan University Hospital and National Taiwan University College of Medicine , Taipei , Taiwan
| | - Wen-Chien Ko
- c Department of Internal Medicine , National Cheng Kung University Hospital , Tainan , Taiwan.,d Department of Medicine , College of Medicine, National Cheng Kung University , Tainan , Taiwan
| | - Hsin-Yun Sun
- e Department of Internal Medicine , National Taiwan University Hospital and National Taiwan University College of Medicine , Taipei , Taiwan
| | - Chien-Ching Hung
- e Department of Internal Medicine , National Taiwan University Hospital and National Taiwan University College of Medicine , Taipei , Taiwan.,f Department of Parasitology , National Taiwan University College of Medicine , Taipei , Taiwan.,g Department of Medical Research , China Medical University Hospital , Taichung , Taiwan.,h China Medical University , Taichung , Taiwan
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Kottom TJ, Hebrink DM, Jenson PE, Ramirez-Prado JH, Limper AH. Characterization of N-Acetylglucosamine Biosynthesis in Pneumocystis species. A New Potential Target for Therapy. Am J Respir Cell Mol Biol 2017; 56:213-222. [PMID: 27632412 DOI: 10.1165/rcmb.2016-0155oc] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
N-acetylglucosamine (GlcNAc) serves as an essential structural sugar on the cell surface of organisms. For example, GlcNAc is a major component of bacterial peptidoglycan, it is an important building block of fungal cell walls, including a major constituent of chitin and mannoproteins, and it is also required for extracellular matrix generation by animal cells. Herein, we provide evidence for a uridine diphospho (UDP)-GlcNAc pathway in Pneumocystis species. Using an in silico search of the Pneumocystis jirovecii and P. murina (Pm) genomic databases, we determined the presence of at least four proteins implicated in the Saccharomyces cerevisiae UDP-GlcNAc biosynthetic pathway. These genes, termed GFA1, GNA1, AGM1, and UDP-GlcNAc pyrophosphorylase (UAP1), were either confirmed to be present in the Pneumocystis genomes by PCR, or, in the case of Pm uap1 (Pmuap1), functionally confirmed by direct enzymatic activity assay. Expression analysis using quantitative PCR of Pneumocystis pneumonia in mice demonstrated abundant expression of the Pm uap1 transcript. A GlcNAc-binding recombinant protein and a novel GlcNAc-binding immune detection method both verified the presence of GlcNAc in P. carinii (Pc) lysates. Studies of Pc cell wall fractions using high-performance gas chromatography/mass spectrometry documented the presence of GlcNAc glycosyl residues. Pc was shown to synthesize GlcNAc in vitro. The competitive UDP-GlcNAc substrate synthetic inhibitor, nikkomycin Z, suppressed incorporation of GlcNAc by Pc preparations. Finally, treatment of rats with Pneumocystis pneumonia using nikkomycin Z significantly reduced organism burdens. Taken together, these data support an important role for GlcNAc generation in the cell surface of Pneumocystis organisms.
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Affiliation(s)
- Theodore J Kottom
- 1 Thoracic Diseases Research Unit, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota; and
| | - Deanne M Hebrink
- 1 Thoracic Diseases Research Unit, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota; and
| | - Paige E Jenson
- 1 Thoracic Diseases Research Unit, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota; and
| | - Jorge H Ramirez-Prado
- 2 Unidad de Biotecnologia, Centro de Investigacion Cientifica de Yucatan, Asociación Civil, Merida, Yucatan, Mexico
| | - Andrew H Limper
- 1 Thoracic Diseases Research Unit, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota; and
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Luraschi A, Cissé OH, Pagni M, Hauser PM. Identification and Functional Ascertainment of the Pneumocystis jirovecii Potential Drug Targets Gsc1 and Kre6 Involved in Glucan Synthesis. J Eukaryot Microbiol 2016; 64:481-490. [PMID: 27859907 DOI: 10.1111/jeu.12385] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 11/11/2016] [Accepted: 11/11/2016] [Indexed: 12/23/2022]
Abstract
The most efficient drug against the human pathogenic fungus Pneumocystis jirovecii is cotrimoxazole targeting the folate biosynthesis. However, resistance toward it is emerging and adverse effects occur in some patients. Studies in rodent models suggested that echinocandins could be useful to treat Pneumocystis pneumonia. Echinocandins inhibit the catalytic subunit Gsc1 of the enzymatic complex ensuring the synthesis of 1,3-β glucan, an essential constituent of cell walls of most fungi. Besides, inhibitors of the enzyme Kre6 involved in the synthesis of 1,6-β glucan, another essential component of fungal walls, were recently described. We identified and functionally characterized these two potential drug targets in the human pathogen P. jirovecii by rescue of the null allele of the orthologous gene in Saccharomyces cerevisiae. The P. jirovecii proteins Gsc1 and Kre6 identified using those of the relative Pneumocystis carinii as the query sequence showed high sequence identity to the putative fungal orthologs (53-97% in conserved functional domains). The expression of their encoding genes on plasmid rescued the increased sensitivity to, respectively, caspofungin or calcofluor white of the corresponding S. cerevisiae null allele. The uniqueness and likely essentiality of these proteins suggest that they are potential good drug targets.
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Affiliation(s)
- Amanda Luraschi
- Institute of Microbiology, Lausanne University Hospital and University of Lausanne, Lausanne, 1011, Switzerland
| | - Ousmane H Cissé
- Institute of Microbiology, Lausanne University Hospital and University of Lausanne, Lausanne, 1011, Switzerland.,Vital-IT Group, SIB Swiss Institute of Bioinformatics, Lausanne, 1015, Switzerland
| | - Marco Pagni
- Vital-IT Group, SIB Swiss Institute of Bioinformatics, Lausanne, 1015, Switzerland
| | - Philippe M Hauser
- Institute of Microbiology, Lausanne University Hospital and University of Lausanne, Lausanne, 1011, Switzerland
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Li H, Huang H, He H. Successful treatment of severe Pneumocystis pneumonia in an immunosuppressed patient using caspofungin combined with clindamycin: a case report and literature review. BMC Pulm Med 2016; 16:144. [PMID: 27835947 PMCID: PMC5106782 DOI: 10.1186/s12890-016-0307-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Accepted: 11/07/2016] [Indexed: 12/16/2022] Open
Abstract
Background Pneumocystis jirovecii is responsible for Pneumocystis pneumonia (PCP), which occurs almost exclusively in immunocompromised individuals. Trimethoprim-sulfamethoxazole (TMP-SMZ) is regarded as the first-line treatment and prophylaxis for P. jirovecii infection, but the frequency of adverse reactions and newly emerged antibiotic resistance limit its use. Case presentation Ulcerations and hemorrhages involving the tongue were noted secondary to TMP-SMZ desensitization against PCP in a 46-year-old male who had previously been diagnosed with IgA nephropathy and sustained prolonged corticosteroid therapy. There was an urgent need for an alternative regimen due to the severe response to TMP-SMZ. The patient was successfully treated with a combination therapy of caspofungin and clindamycin. Conclusion Caspofungin combined with clindamycin is an optional treatment for PCP when treatment with TMP-SMZ fails or in patients who cannot tolerate TMP-SMZ.
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Affiliation(s)
- Hongjuan Li
- Department of Emergency, Guangdong Hospital of Traditional Chinese Medicine, Guangzhou, Guangdong, 510105, China.
| | - Haoming Huang
- Department of Emergency, Guangzhou University of Traditional Chinese Medicine First Affiliated Hospital, Guangzhou, Guangdong, 510405, China
| | - Hangyong He
- Department of Respiratory and Critical Care Medicine, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China.
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Song JC, Stevens DA. Caspofungin: Pharmacodynamics, pharmacokinetics, clinical uses and treatment outcomes. Crit Rev Microbiol 2015; 42:813-46. [PMID: 26369708 DOI: 10.3109/1040841x.2015.1068271] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Over the past decade, echinocandins have emerged as first-line antifungal agents for many Candida infections. The echinocandins have a unique mechanism of action, inhibiting the synthesis of β-1,3-d-glucan polymers, key components of the cell wall in pathogenic fungi. Caspofungin was the first echinocandin antifungal agent to become licensed for use. The objectives of this review are to summarize the existing published data on caspofungin, under the subject headings of chemistry and mechanism of action, spectrum of activity, pharmacodynamics, pharmacokinetics, clinical studies, safety, drug interactions, dosing, and an overview of the drug's current place in therapy.
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Affiliation(s)
- Jessica C Song
- a Department of Pharmacy , Santa Clara Valley Medical Center , San Jose , CA , USA .,b California Institute for Medical Research , San Jose , CA , USA , and
| | - David A Stevens
- b California Institute for Medical Research , San Jose , CA , USA , and.,c Division of Infectious Diseases and Geographic Medicine , Stanford University School of Medicine , Stanford , CA , USA
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Skalski JH, Kottom TJ, Limper AH. Pathobiology of Pneumocystis pneumonia: life cycle, cell wall and cell signal transduction. FEMS Yeast Res 2015; 15:fov046. [PMID: 26071598 DOI: 10.1093/femsyr/fov046] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/08/2015] [Indexed: 12/28/2022] Open
Abstract
Pneumocystis is a genus of ascomycetous fungi that are highly morbid pathogens in immunosuppressed humans and other mammals. Pneumocystis cannot easily be propagated in culture, which has greatly hindered understanding of its pathobiology. The Pneumocystis life cycle is intimately associated with its mammalian host lung environment, and life cycle progression is dependent on complex interactions with host alveolar epithelial cells and the extracellular matrix. The Pneumocystis cell wall is a varied and dynamic structure containing a dominant major surface glycoprotein, β-glucans and chitins that are important for evasion of host defenses and stimulation of the host immune system. Understanding of Pneumocystis cell signaling pathways is incomplete, but much has been deduced by comparison of the Pneumocystis genome with homologous genes and proteins in related fungi. In this mini-review, the pathobiology of Pneumocystis is reviewed, with particular focus on the life cycle, cell wall components and cell signal transduction.
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Affiliation(s)
- Joseph H Skalski
- Thoracic Diseases Research Unit, Division of Pulmonary and Critical Care Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Theodore J Kottom
- Thoracic Diseases Research Unit, Division of Pulmonary and Critical Care Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Andrew H Limper
- Thoracic Diseases Research Unit, Division of Pulmonary and Critical Care Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
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Liesche J, Marek M, Günther-Pomorski T. Cell wall staining with Trypan blue enables quantitative analysis of morphological changes in yeast cells. Front Microbiol 2015; 6:107. [PMID: 25717323 PMCID: PMC4324143 DOI: 10.3389/fmicb.2015.00107] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Accepted: 01/27/2015] [Indexed: 11/13/2022] Open
Abstract
Yeast cells are protected by a cell wall that plays an important role in the exchange of substances with the environment. The cell wall structure is dynamic and can adapt to different physiological states or environmental conditions. For the investigation of morphological changes, selective staining with fluorescent dyes is a valuable tool. Furthermore, cell wall staining is used to facilitate sub-cellular localization experiments with fluorescently-labeled proteins and the detection of yeast cells in non-fungal host tissues. Here, we report staining of Saccharomyces cerevisiae cell wall with Trypan Blue, which emits strong red fluorescence upon binding to chitin and yeast glucan; thereby, it facilitates cell wall analysis by confocal and super-resolution microscopy. The staining pattern of Trypan Blue was similar to that of the widely used UV-excitable, blue fluorescent cell wall stain Calcofluor White. Trypan Blue staining facilitated quantification of cell size and cell wall volume when utilizing the optical sectioning capacity of a confocal microscope. This enabled the quantification of morphological changes during growth under anaerobic conditions and in the presence of chemicals, demonstrating the potential of this approach for morphological investigations or screening assays.
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Affiliation(s)
- Johannes Liesche
- Department of Plant and Environmental Sciences, University of Copenhagen Copenhagen, Denmark
| | - Magdalena Marek
- Department of Plant and Environmental Sciences, University of Copenhagen Copenhagen, Denmark
| | - Thomas Günther-Pomorski
- Department of Plant and Environmental Sciences, University of Copenhagen Copenhagen, Denmark
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