The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform

Andrew H. Limper - One of the best experts on this subject based on the ideXlab platform.

  • Preadmission Corticosteroid Therapy and the Risk of Respiratory Failure in Adults Without HIV Presenting With Pneumocystis Pneumonia.
    Journal of intensive care medicine, 2019
    Co-Authors: Patrick M. Wieruszewski, Erin F. Barreto, Jason N. Barreto, Hemang Yadav, Pritish K. Tosh, Kristin C. Mara, Andrew H. Limper
    Abstract:

    Background:Corticosteroid therapy is a well-recognized risk factor for Pneumocystis Pneumonia (PCP); however, it has also been proposed as an adjunct to decrease inflammation and respiratory failur...

  • Update on the Diagnosis and Treatment of Pneumocystis Pneumonia
    Therapeutic advances in respiratory disease, 2010
    Co-Authors: Eva M. Carmona, Andrew H. Limper
    Abstract:

    Pneumocystis is an opportunistic fungal pathogen that causes an often-lethal Pneumonia in immunocompromised hosts. Although the organism was discovered in the early 1900s, the first cases of Pneumocystis Pneumonia in humans were initially recognized in Central Europe after the Second World War in premature and malnourished infants. This unusual lung infection was known as plasma cellular interstitial pneumonitis of the newborn, and was characterized by severe respiratory distress and cyanosis with little or no fever and no pathognomic physical signs. At that time, only anecdotal cases were reported in adults and usually these patients had a baseline malignancy that led to a malnourished state. In the 1960-1970s additional cases were described in adults and children with hematological malignancies, but Pneumocystis Pneumonia was still considered a rare disease. However, in the 1980s, with the onset of the HIV epidemic, Pneumocystis prevalence increased dramatically and became widely recognized as an opportunistic infection that caused potentially life-treating Pneumonia in patients with impaired immunity. During this time period, prophylaxis against this organism was more generally instituted in high-risk patients. In the 1990s, with widespread use of prophylaxis and the initiation of highly active antiretroviral therapy (HAART) in the treatment of HIV-infected patients, the number of cases in this specific population decreased. However, Pneumocystis Pneumonia still remains an important cause of severe Pneumonia in patients with HIV infection and is still considered a principal AIDS-defining illness. Despite the decreased number of cases among HIV-infected patients over the past decade, Pneumocystis Pneumonia continues to be a serious problem in immunodeficient patients with other immunosuppressive conditions. This is mostly due to increased use of immunosuppressive medications to treat patients with autoimmune diseases, following bone marrow and solid organ transplantation, and in patients with hematological and solid malignancies. Patients with hematologic disorders and solid organ and hematopoietic stem cell transplantation are currently the most vulnerable groups at risk for developing this infection. However, any patient with an impaired immunity, such as those receiving moderate doses of oral steroids for greater than 4 weeks or those receiving other immunosuppressive medications are at also at significant risk.

  • Pneumocystis Pneumonia: Current Concepts in Pathogenesis, Diagnosis, and Treatment
    Clinics in chest medicine, 2009
    Co-Authors: Bryan J. Krajicek, Charles F. Thomas, Andrew H. Limper
    Abstract:

    Pneumocystis Pneumonia (PCP) is an infection of the lungs caused by the opportunistic fungal genus Pneumocystis. In humans, PCP is a serious and potentially life-threatening infection occurring in immunocompromised individuals, particularly those who have AIDS, or following immune suppression from malignancy, organ transplantation, or therapies for inflammatory diseases. Several recent studies have contributed to understanding of the biology and pathogenesis of the organism yielding new diagnostic approaches and therapeutic targets. Although trimethoprim-sulfamethoxazole remains the mainstay of prophylaxis and treatment, ongoing concerns for emerging Pneumocystis resistance supports the continuing investigation for novel therapeutic agents.

Anne Totet - One of the best experts on this subject based on the ideXlab platform.

  • Quantification and Spread of Pneumocystis jirovecii in the Surrounding Air of Patients with Pneumocystis Pneumonia
    Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2010
    Co-Authors: Firas Choukri, Jean Menotti, Claudine Sarfati, Jean-christophe Lucet, Gilles Nevez, Yves J. F. Garin, Francis Derouin, Anne Totet
    Abstract:

    Background. Airborne transmission of Pneumocystis has been demonstrated in animal models and is highly probable in humans. However, information concerning burdens of Pneumocystis jirovecii (human-derived Pneumocystis) in exhaled air from infected patients is lacking. Our objective is to evaluate P. jirovecii air diffusion in patients with Pneumocystis Pneumonia. Methods. Patients admitted with Pneumocystis Pneumonia were prospectively enrolled from 9 January 2008 to 21 July 2009. Air samples (1.5 m 3 ) were collected on liquid medium with a commercial sampler at 1-, 3-, 5-, and 8-m distances from patients' heads. Air control samples were collected away from Pneumocystis Pneumonia patient wards and outdoors. Samples were examined for P. jirovecii detection and quantification using a real-time polymerase chain reaction assay targeting the mitochondrial large subunit ribosomal RNA gene. Results. Forty patients were diagnosed as having Pneumocystis Pneumonia. Air sampling was performed in the environment for 19 of them. At a 1-m distance from patients' heads, P. jirovecii DNA was detected in 15 (79.8%) of 19 patients, with fungal burdens ranging from 7.5 X 10 3 to 4.5 X 10 6 gene copies/m 3 . These levels decreased with distance from the patients (P

  • quantification and spread of Pneumocystis jirovecii in the surrounding air of patients with Pneumocystis Pneumonia
    Clinical Infectious Diseases, 2010
    Co-Authors: Firas Choukri, Jean Menotti, Claudine Sarfati, Jean-christophe Lucet, Gilles Nevez, Yves J. F. Garin, Francis Derouin, Anne Totet
    Abstract:

    Background. Airborne transmission of Pneumocystis has been demonstrated in animal models and is highly probable in humans. However, information concerning burdens of Pneumocystis jirovecii (human-derived Pneumocystis) in exhaled air from infected patients is lacking. Our objective is to evaluate P. jirovecii air diffusion in patients with Pneumocystis Pneumonia. Methods. Patients admitted with Pneumocystis Pneumonia were prospectively enrolled from 9 January 2008 to 21 July 2009. Air samples (1.5 m 3 ) were collected on liquid medium with a commercial sampler at 1-, 3-, 5-, and 8-m distances from patients' heads. Air control samples were collected away from Pneumocystis Pneumonia patient wards and outdoors. Samples were examined for P. jirovecii detection and quantification using a real-time polymerase chain reaction assay targeting the mitochondrial large subunit ribosomal RNA gene. Results. Forty patients were diagnosed as having Pneumocystis Pneumonia. Air sampling was performed in the environment for 19 of them. At a 1-m distance from patients' heads, P. jirovecii DNA was detected in 15 (79.8%) of 19 patients, with fungal burdens ranging from 7.5 X 10 3 to 4.5 X 10 6 gene copies/m 3 . These levels decreased with distance from the patients (P<.002). Nevertheless, 4 (33.3%) of the 12 samples taken at 8 m, in the corridor adjacent to their room, were still positive. Forty control samples were collected and remained negative. Conclusion. This study provides the first quantitative data on the spread of P. jirovecii in exhaled air from infected patients. It sustains the risk of P. jirovecii direct transmission in close contact with patients with Pneumocystis Pneumonia and leads the way for initiating a quantitative risk assessment for airborne transmission of P. jirovecii.

Naoto Tamura - One of the best experts on this subject based on the ideXlab platform.

Gilles Nevez - One of the best experts on this subject based on the ideXlab platform.

  • Quantification and Spread of Pneumocystis jirovecii in the Surrounding Air of Patients with Pneumocystis Pneumonia
    Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2010
    Co-Authors: Firas Choukri, Jean Menotti, Claudine Sarfati, Jean-christophe Lucet, Gilles Nevez, Yves J. F. Garin, Francis Derouin, Anne Totet
    Abstract:

    Background. Airborne transmission of Pneumocystis has been demonstrated in animal models and is highly probable in humans. However, information concerning burdens of Pneumocystis jirovecii (human-derived Pneumocystis) in exhaled air from infected patients is lacking. Our objective is to evaluate P. jirovecii air diffusion in patients with Pneumocystis Pneumonia. Methods. Patients admitted with Pneumocystis Pneumonia were prospectively enrolled from 9 January 2008 to 21 July 2009. Air samples (1.5 m 3 ) were collected on liquid medium with a commercial sampler at 1-, 3-, 5-, and 8-m distances from patients' heads. Air control samples were collected away from Pneumocystis Pneumonia patient wards and outdoors. Samples were examined for P. jirovecii detection and quantification using a real-time polymerase chain reaction assay targeting the mitochondrial large subunit ribosomal RNA gene. Results. Forty patients were diagnosed as having Pneumocystis Pneumonia. Air sampling was performed in the environment for 19 of them. At a 1-m distance from patients' heads, P. jirovecii DNA was detected in 15 (79.8%) of 19 patients, with fungal burdens ranging from 7.5 X 10 3 to 4.5 X 10 6 gene copies/m 3 . These levels decreased with distance from the patients (P

  • quantification and spread of Pneumocystis jirovecii in the surrounding air of patients with Pneumocystis Pneumonia
    Clinical Infectious Diseases, 2010
    Co-Authors: Firas Choukri, Jean Menotti, Claudine Sarfati, Jean-christophe Lucet, Gilles Nevez, Yves J. F. Garin, Francis Derouin, Anne Totet
    Abstract:

    Background. Airborne transmission of Pneumocystis has been demonstrated in animal models and is highly probable in humans. However, information concerning burdens of Pneumocystis jirovecii (human-derived Pneumocystis) in exhaled air from infected patients is lacking. Our objective is to evaluate P. jirovecii air diffusion in patients with Pneumocystis Pneumonia. Methods. Patients admitted with Pneumocystis Pneumonia were prospectively enrolled from 9 January 2008 to 21 July 2009. Air samples (1.5 m 3 ) were collected on liquid medium with a commercial sampler at 1-, 3-, 5-, and 8-m distances from patients' heads. Air control samples were collected away from Pneumocystis Pneumonia patient wards and outdoors. Samples were examined for P. jirovecii detection and quantification using a real-time polymerase chain reaction assay targeting the mitochondrial large subunit ribosomal RNA gene. Results. Forty patients were diagnosed as having Pneumocystis Pneumonia. Air sampling was performed in the environment for 19 of them. At a 1-m distance from patients' heads, P. jirovecii DNA was detected in 15 (79.8%) of 19 patients, with fungal burdens ranging from 7.5 X 10 3 to 4.5 X 10 6 gene copies/m 3 . These levels decreased with distance from the patients (P<.002). Nevertheless, 4 (33.3%) of the 12 samples taken at 8 m, in the corridor adjacent to their room, were still positive. Forty control samples were collected and remained negative. Conclusion. This study provides the first quantitative data on the spread of P. jirovecii in exhaled air from infected patients. It sustains the risk of P. jirovecii direct transmission in close contact with patients with Pneumocystis Pneumonia and leads the way for initiating a quantitative risk assessment for airborne transmission of P. jirovecii.

  • Strain typing methods and molecular epidemiology of Pneumocystis Pneumonia.
    Emerging infectious diseases, 2004
    Co-Authors: Charles B. Beard, Gilles Nevez, Joseph A Kovacs, Patricia Roux, Philippe M. Hauser, Thomas R. Unnasch, Bettina Lundgren
    Abstract:

    Pneumocystis Pneumonia (PCP) caused by the opportunistic fungal agent Pneumocystis jirovecii (formerly P. carinii) continues to cause illness and death in HIV-infected patients. In the absence of a culture system to isolate and maintain live organisms, efforts to type and characterize the organism have relied on polymerase chain reaction-based approaches. Studies using these methods have improved understanding of PCP epidemiology, shedding light on sources of infection, transmission patterns, and potential emergence of antimicrobial resistance. One concern, however, is the lack of guidance regarding the appropriateness of different methods and standardization of these methods, which would facilitate comparing results reported by different laboratories.

Ruming Xie - One of the best experts on this subject based on the ideXlab platform.

  • Differences and similarities of high-resolution computed tomography features between Pneumocystis Pneumonia and cytomegalovirus Pneumonia in AIDS patients.
    Infectious diseases of poverty, 2020
    Co-Authors: Jingyuan Liu, Hui Chen, Shuo Yan, Haofeng Xiong, Pan Xiang, Ming Zhang, Ruming Xie
    Abstract:

    Background Accurately differentiating Pneumocystis from cytomegalovirus Pneumonia is crucial for correct therapy selection in AIDS patients. Hence, the goal of this study was to compare the computerized tomography (CT) features of Pneumocystis Pneumonia and cytomegalovirus Pneumonia in AIDS patients and identify clinical hallmarks to accurately distinguish these two pathologies. Methods A total of 112 AIDS patients (78 with Pneumocystis Pneumonia and 34 cytomegalovirus Pneumonia) at Beijing Ditan Hospital from January 2017 to May 2019 were included in this study. Two experienced chest radiologists retrospectively reviewed CT images for 17 features including ground-glass opacity, consolidation, nodules, and halo sign. Binary logistic regression analyses were conducted to identify the significant parameters that distinguished Pneumocystis Pneumonia from cytomegalovirus Pneumonia. Correlations were analyzed by Pearson or Spearman correlation analyses. Result were considered significant if P Results The presence of consolidation, halo signs, and nodules (all P 0.05) were common in both groups. Conclusions Analysis of consolidation, nodules, and halo signs may contribute to the differential diagnosis of Pneumocystis Pneumonia or cytomegalovirus Pneumonia. However, some CT features considered typical in one or other diseases appear with similar frequency in both cohorts of AIDS patients. CT features are potentially useful for the differential diagnosis of Pneumocystis Pneumonia and cytomegalovirus Pneumonia in AIDS patients.

  • Differences and similarities of high-resolution computed tomography features between Pneumocystis Pneumonia and cytomegalovirus Pneumonia in AIDS patients
    2020
    Co-Authors: Jingyuan Liu, Hui Chen, Shuo Yan, Haofeng Xiong, Pan Xiang, Ming Zhang, Ruming Xie
    Abstract:

    Abstract Background: Accurately differentiating Pneumocystis from cytomegalovirus Pneumonia is crucial for correct therapy selection in AIDS patients. Hence, the goal of this study was to compare the computerized tomography (CT ) features of Pneumocystis Pneumonia and cytomegalovirus Pneumonia in AIDS patients and identify clinical hallmarks to accurately distinguish these two pathologies. Methods: A total of 112 AIDS patients (78 with Pneumocystis Pneumonia and 34 cytomegalovirus Pneumonia) at Beijing Ditan Hospital from January 2017 to May 2019 were included in this study. Two experienced chest radiologists retrospectively reviewed CT images for 17 features including ground-glass opacity, consolidation, nodules, and halo sign. Binary logistic regression analyses were conducted to identify the significant parameters that distinguished Pneumocystis Pneumonia from cytomegalovirus Pneumonia. Correlations were analyzed by Pearson or Spearman correlation analyses. Result were considered significant if P < 0.05. Results: The presence of consolidation, halo signs, and nodules (all P ＜0.05) were significantly more frequent in patients with cytomegalovirus Pneumonia than in those with Pneumocystis Pneumonia. Small nodules (32.5% in cytomegalovirus Pneumonia, 6.41% in Pneumocystis Pneumonia, P ＜0.001) without perilymphatic distribution were particularly common in patients with cytomegalovirus Pneumonia. Large nodules were not found in any of patients with cytomegalovirus Pneumonia. The presence of ground-glass opacity, reticulation, and bronchial wall thickening (all P > 0.05) were common in both groups. Conclusions: Analysis of consolidation, nodules, and halo signs may contribute to the differential diagnosis of Pneumocystis Pneumonia or cytomegalovirus Pneumonia. However, some CT features considered typical in one or other diseases appear with similar frequency in both cohorts of AIDS patients. CT features are potentially useful for the differential diagnosis of Pneumocystis Pneumonia and cytomegalovirus Pneumonia in AIDS patients.

  • Differences and similarities of high-resolution computed tomography features between Pneumocystis Pneumonia and Cytomegalovirus Pneumonia in AIDS patients
    2020
    Co-Authors: Jingyuan Liu, Hui Chen, Shuo Yan, Haofeng Xiong, Pan Xiang, Ming Zhang, Ruming Xie
    Abstract:

    Abstract Background: Accurately differentiating Pneumocystis from cytomegalovirus Pneumonia is crucial for correct therapy selection in AIDS patients. Hence, the goal of this study was to compare the computerized tomography (CT) features of Pneumocystis Pneumonia and cytomegalovirus Pneumonia in AIDS patients and identify clinical hallmarks to accurately distinguish these two pathologies.Methods: A total of 112 AIDS patients (78 with Pneumocystis Pneumonia and 34 cytomegalovirus Pneumonia) at Beijing Ditan Hospital from January 2017 to May 2019 were included in this study. Two experienced chest radiologists retrospectively reviewed CT images for 17 features including ground-glass opacity, consolidation, nodules, and halo sign. Significance was calculated by the chi-square (χ2) test. Binary logistic regression analyses were conducted to identify the significant parameters that distinguished Pneumocystis Pneumonia from cytomegalovirus Pneumonia. Correlations were analyzed by Pearson or Spearman correlation analyses. Result were considered significant if P < 0.05.Results: The presence of consolidation, halo signs, and nodules (all P＜0.05) were significantly more frequent in patients with cytomegalovirus Pneumonia than in those with Pneumocystis Pneumonia. Small nodules (32.5% in cytomegalovirus Pneumonia, 6.41% in Pneumocystis Pneumonia, P＜0.001) without perilymphatic distribution were particularly common in patients with cytomegalovirus Pneumonia. Large nodules were not found in any of patients with cytomegalovirus Pneumonia. The presence of ground-glass opacity, reticulation, and bronchial wall thickening (all P > 0.05) were common in both groups. Conclusions: Analysis of consolidation, nodules, and halo signs may contribute to the differential diagnosis of Pneumocystis Pneumonia or cytomegalovirus Pneumonia. However, some CT features considered typical in one or other diseases appear with similar frequency in both cohorts of AIDS patients. CT features are potentially useful for the differential diagnosis of Pneumocystis Pneumonia and cytomegalovirus Pneumonia in AIDS patients. Add potential implications