<i>Pneumocystis</i> Colonization in HIV‐Infected Patients

Huang, Laurence; Crothers, Kristina; Morris, Alison; Groner, Gena; Fox, Melissa; Turner, Joan; Merrifield, Cynthia; Eiser, Shary; Zucchi, Patrizia; Beard, Charles B.

doi:10.1111/j.1550-7408.2003.tb00651.x

Cited by 53 publications

(38 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Interestingly, a study by Morris et al (50) found an association of chronic obstructive pulmonary lung disease severity and Pneumocystis colonization of the lung in patients with chronic obstructive pulmonary lung disease. Furthermore, there are increasing reports of pulmonary complications in AIDS patients, such as emphysema, pulmonary hypertension, noninfectious inflammatory disease, and asthma, as well as the clinical presentation of PCP as asthma (51)(52)(53). It is likely that depending on the immune status of a patient infected with HIV, the clinical manifestation of Pneumocystis infection is variable, and chronic colonization (that may or may not be detectable) in a partially immune-reconstituted patient may lead to pulmonary complications other than classical PCP.…”

Section: Discussionmentioning

confidence: 99%

Role of Type I IFNs in Pulmonary Complications of Pneumocystis murina Infection

Meissner

Swain

Tighe

et al. 2005

The Journal of Immunology

View full text Add to dashboard Cite

Despite the advent of highly active antiretroviral therapy, pulmonary complications in AIDS are a common clinical problem. Pneumocystis jiroveci infection causes a life-threatening pneumonia, especially in individuals with CD4 T cell deficiencies as occurs in AIDS. Although Pneumocystis sp. is an extracellular fungal pathogen, CD8 T cells are the predominant lymphocyte recruited to the lung in CD4-deficient humans and mice during Pneumocystis pneumonia, and we have found that these CD8 T cells are responsible for subsequent lung damage in CD4 T cell-depleted mice. Comparing CD4 T cell-depleted IFN-α receptor knockout (KO) mice to wild-type mice, we found that this CD8 T cell recruitment and lung damage is type I IFN (IFN-αβ) dependent. However, in both CD4 competent, wild-type and IFN-α receptor (IFNAR) KO mice, Pneumocystis infection leads to an eosinophilic granulocyte influx with bronchial epithelial changes as seen in asthma. This response is delayed in IFNAR KO mice, as is pathogen clearance. Although the inflammation is transient in wild-type animals and resolves upon Pneumocystis clearance, it is more severe and persists through day 35 postinfection in IFNAR KO mice, leading to fibrosis. In addition, IFNAR KO, but not wild-type, mice mount a Pneumocystis-specific IgE response, an indicator of allergic sensitization. Thus, in the absence of IFNAR signaling and CD4 T cells, Pneumocystis-mediated lung damage does not occur, whereas in CD4-competent animals, the absence of IFNAR signaling results in an exacerbated Th2 response, asthma-like symptoms, and fibrosis. Therefore, both CD4 T cell- and type I IFN-mediated mechanisms can determine pulmonary complications from Pneumocystis infection.

show abstract

Section: Discussionmentioning

confidence: 99%

Role of Type I IFNs in Pulmonary Complications of Pneumocystis murina Infection

Meissner

Swain

Tighe

et al. 2005

The Journal of Immunology

View full text Add to dashboard Cite

show abstract

“…Colonization has also been noted in patients with various chronic disease such as diabetes mellitus, sarcoidosis, and multiple myeloma (230). (107,121,174,217,230,249,285,308,310). This variability likely results from differences in the patient populations studied, the samples collected, and the use of different detection methods.…”

Section: Colonization In Animalsmentioning

confidence: 99%

“…This variability likely results from differences in the patient populations studied, the samples collected, and the use of different detection methods. A higher prevalence of colonization is more common in inpatients with pneumonia or in HIV-infected individuals dying from causes other than PCP (121,217). The most recent study of colonization in HIV examined oropharyngeal washes from 20 HIV-infected teenagers without respiratory symptoms and found colonization in 20% (107).…”

Section: Colonization In Animalsmentioning

confidence: 99%

“…One study found that colonization increased from 10% in persons with a CD4 ϩ cell count of greater than 400 cells/l to 40% in those with counts of less than 60 cells/l (175). Other studies have not replicated this relationship, and it is clear that colonization does occur even in individuals with higher CD4 cell counts as well as those on antiretroviral therapy or anti-Pneumocystis prophylaxis (121,217). Other risk factors for colonization in HIV include cigarette smoking and geographic location (217).…”

Section: Colonization In Animalsmentioning

confidence: 99%

See 1 more Smart Citation

Colonization by Pneumocystis jirovecii and Its Role in Disease

2012

Self Cite

View full text Add to dashboard Cite

SUMMARY Although the incidence of Pneumocystis pneumonia (PCP) has decreased since the introduction of combination antiretroviral therapy, it remains an important cause of disease in both HIV-infected and non-HIV-infected immunosuppressed populations. The epidemiology of PCP has shifted over the course of the HIV epidemic both from changes in HIV and PCP treatment and prevention and from changes in critical care medicine. Although less common in non-HIV-infected immunosuppressed patients, PCP is now more frequently seen due to the increasing numbers of organ transplants and development of novel immunotherapies. New diagnostic and treatment modalities are under investigation. The immune response is critical in preventing this disease but also results in lung damage, and future work may offer potential areas for vaccine development or immunomodulatory therapy. Colonization with Pneumocystis is an area of increasing clinical and research interest and may be important in development of lung diseases such as chronic obstructive pulmonary disease. In this review, we discuss current clinical and research topics in the study of Pneumocystis and highlight areas for future research.

show abstract

“…HIVinfected individuals are at increased risk of oral and esophageal candidiasis and other fungal diseases, and Candida is a normal colonizer of mucosal surfaces. We have also found that the fungus Pneumocystis is a frequent respiratory colonizer in HIVinfected individuals, particularly in those with COPD (34)(35)(36). (1→3)-b-D-glucan (BG) is a component of fungal cell walls that is shed into the blood and can be detected in the serum of patients with fungal pneumonia (37,38).…”

Section: Fungi As Possible Agents Of Microbial Translocationmentioning

confidence: 99%

Heart–Lung Interaction via Infection

Morris

2014

Annals ATS

Self Cite

View full text Add to dashboard Cite

Lung and cardiovascular disease are increasingly recognized to occur in the same patient populations. Infections, either through stimulation of inflammation or through direct infection, can lead to end-organ damage and have been postulated as a potential link between lung and cardiovascular diseases. Mechanisms by which infections may link lung and cardiac diseases include effects of systemic infections, microbial translocation of pathogens from the gastrointestinal tract or other sites, damaging effects of metabolic products, or influences of smoking on the microbiome.Other mechanisms, such as alterations in the local microbiome, environmental exposures, or immune regulation by microbial communities, may be important. These relationships are likely quite complex, with multiple routes between infection and disease possible. A better understanding of the links of infection to lung and heart disease can improve our understanding of the pathogenesis of these disorders and uncover novel therapeutic approaches.Keywords: microbial translocation; metabolomics; pulmonary function; cardiovascular; HIV Correspondence and requests for reprints should be addressed to Alison Morris, M.D., M.S.,

show abstract

Pneumocystis Colonization in HIV‐Infected Patients

Cited by 53 publications

References 24 publications

Role of Type I IFNs in Pulmonary Complications of Pneumocystis murina Infection

Role of Type I IFNs in Pulmonary Complications of Pneumocystis murina Infection

Colonization by Pneumocystis jirovecii and Its Role in Disease

Heart–Lung Interaction via Infection

Contact Info

Product

Resources

About