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Antimicrobial Agents and Chemotherapy Oct 2019
Topics: Caspofungin; Catalytic Domain; Glucosyltransferases; Humans; Mutagenesis, Site-Directed; Pneumocystis carinii; Pneumonia, Pneumocystis
PubMed: 31548211
DOI: 10.1128/AAC.01320-19 -
Emerging Infectious Diseases Sep 2002The disease known as Pneumocystis carinii pneumonia (PCP) is a major cause of illness and death in persons with impaired immune systems. While the genus Pneumocystis has... (Review)
Review
The disease known as Pneumocystis carinii pneumonia (PCP) is a major cause of illness and death in persons with impaired immune systems. While the genus Pneumocystis has been known to science for nearly a century, understanding of its members remained rudimentary until DNA analysis showed its extensive diversity. Pneumocystis organisms from different host species have very different DNA sequences, indicating multiple species. In recognition of its genetic and functional distinctness, the organism that causes human PCP is now named Pneumocystis jiroveci Frenkel 1999. Changing the organism's name does not preclude the use of the acronym PCP because it can be read "Pneumocystis pneumonia." DNA sequence variation exists among samples of P. jiroveci, a feature that allows reexamination of the relationships between host and pathogen. Instead of lifelong latency, transient colonization may be the rule.
Topics: AIDS-Related Opportunistic Infections; Acquired Immunodeficiency Syndrome; Genotype; Humans; Phylogeny; Pneumocystis; Pneumocystis Infections; Pneumonia, Pneumocystis; Species Specificity; Terminology as Topic
PubMed: 12194762
DOI: 10.3201/eid0809.020096 -
Journal de Mycologie Medicale Mar 2023To analyze clinical characteristics and risk factors for in-hospital mortality in patients coinfected with P. jirovecii and Aspergillus.
OBJECTIVE
To analyze clinical characteristics and risk factors for in-hospital mortality in patients coinfected with P. jirovecii and Aspergillus.
METHODS
This study included 53 patients with coinfection of P. jirovecii pneumonia (PJP) and invasive pulmonary aspergillosis (IPA) in our center from January 2011 to December 2021. All cases were divided into survivor (n=27) and non-survivor groups (n=26). Medical records, laboratory and radiology data were collected. Risk factors for in-hospital mortality were identified by multivariable analyses.
RESULTS
HIV-positive patients accounted for 3.8%. Fever (77.4%), dyspnea (69.8%) and wet cough (24.5%) were common symptoms. Ground-glass opacity (83.0%), consolidation (71.7%), septal thickening (66.0%), and nodules (54.7%) were the most common radiological signs. CD4+ T cell count and serum albumin (ALB) level were significantly lower in non-survival group than in the survival group. Conversely, serum lactate dehydrogenase (LDH) and procalcitonin (PCT) levels were higher in non-survival group than in survival group. Lactic acidosis [odds ratio (OR): 33.999,95% confidential interval (CI): 3.112-371.409; p=0.004], low CD4+ T cell count (<114 cell/µL) [OR: 19.343, 95% CI: 1.533-259.380; p=0.022] and high level of LDH (> 519 U/L) [OR: 11.422, 95% CI: 1.271-102.669; p=0.030] were independent risk factors for mortality.
CONCLUSION
PJP coinfected with IPA incurs high mortality with nonspecific clinical characteristics and is more likely to involve HIV-negative patients. Lactic acidosis, low CD4+ T cell count and high LDH level are independent risk factors for mortality, close monitoring of these parameters is necessary to help distinguish high-risk patients and make appropriate clinical decisions.
Topics: Humans; Pneumocystis carinii; Coinfection; Hospital Mortality; Acidosis, Lactic; HIV Infections; Risk Factors; Pneumonia, Pneumocystis; Aspergillus; Invasive Pulmonary Aspergillosis; Retrospective Studies
PubMed: 36265259
DOI: 10.1016/j.mycmed.2022.101330 -
Medical Mycology Oct 2019The genus Pneumocystis comprises potential pathogens that reside normally in the lungs of a wide range of mammals. Although they generally behave as transient or...
The genus Pneumocystis comprises potential pathogens that reside normally in the lungs of a wide range of mammals. Although they generally behave as transient or permanent commensals, they can occasionally cause life-threatening pneumonia (Pneumocystis pneumonia; PCP) in immunosuppressed individuals. Several decades ago, the presence of Pneumocystis morphotypes (trophic forms and cysts) was described in the lungs of normal cats and cats with experimentally induced symptomatic PCP (after immunosuppression by corticosteroids); yet to date spontaneous or drug-induced PCP has not been described in the clinical feline literature, despite immunosuppression of cats by long-standing retrovirus infections or after kidney transplantation. In this study, we describe the presence of Pneumocystis DNA in the lungs of normal cats (that died of various unrelated causes; n = 84) using polymerase chain reactions (PCRs) targeting the mitochondrial small and large subunit ribosomal RNA gene (mtSSU rRNA and mtLSU rRNA). The presence of Pneumocystis DNA was confirmed by sequencing in 24/84 (29%) cats, with evidence of two different sequence types (or lineages). Phylogenetically, lineage1 (L1; 19 cats) and lineage 2 (L2; 5 cats) formed separate clades, clustering with Pneumocystis from domestic pigs (L1) and carnivores (L2), respectively. Results of the present study support the notion that cats can be colonized or subclinically infected by Pneumocystis, without histological evidence of damage to the pulmonary parenchyma referable to pneumocystosis. Pneumocystis seems most likely an innocuous pathogen of cats' lungs, but its possible role in the exacerbation of chronic pulmonary disorders or viral/bacterial coinfections should be considered further in a clinical setting.
Topics: Animals; Cat Diseases; Cats; DNA, Fungal; Female; Lung; Male; Phylogeny; Pneumocystis; Pneumonia, Pneumocystis; RNA, Mitochondrial; RNA, Ribosomal
PubMed: 30566653
DOI: 10.1093/mmy/myy139 -
Indian Journal of Pediatrics Aug 2023
Topics: Humans; Pneumocystis carinii; SARS-CoV-2; Coinfection; X-Linked Combined Immunodeficiency Diseases; COVID-19; Pneumonia, Pneumocystis
PubMed: 37249831
DOI: 10.1007/s12098-023-04661-2 -
Frontiers in Public Health 2021We performed a meta-analysis to systematically review the risk factors of mortality from non-HIV-related pneumonia (PcP) and provide the theoretical basis for managing... (Meta-Analysis)
Meta-Analysis
We performed a meta-analysis to systematically review the risk factors of mortality from non-HIV-related pneumonia (PcP) and provide the theoretical basis for managing non-HIV-related PcP. PubMed, Embase, Web of Science, the Cochrane Library and CNKI databases were searched. A meta-analysis of the risk factors of mortality from non-HIV-related PcP was conducted. A total of 19 studies and 1,310 subjects were retrieved and included in the meta-analysis, including 485 and 825 patients in the non-survivor and survivor groups, respectively. In the primary analysis, age, concomitant with other pulmonary diseases at diagnosis of PcP, solid tumors, cytomegalovirus(CMV) co-infection, lactate dehydrogenase (LDH), lymphocyte count, invasive ventilation during hospitalization, and pneumothorax were associated with mortality from non-HIV-related PcP, whereas sex, albumin, PcP prophylaxis, use of corticosteroids after admission, and time from onset of symptoms to treatment were not associated with mortality from non-HIV-related PcP. The mortality rate of non-HIV-infected patients with PcP was still high. Age, concomitant with other pulmonary diseases at diagnosis of PcP, solid tumors, CMV co-infection, LDH, lymphocyte count, invasive ventilation during hospitalization, and pneumothorax were risk factors of mortality from non-HIV-related PcP. Improved knowledge of prognostic factors is crucial to guide early treatment.
Topics: Coinfection; Cytomegalovirus Infections; Humans; Pneumocystis; Pneumonia, Pneumocystis; Risk Factors
PubMed: 34222179
DOI: 10.3389/fpubh.2021.680108 -
Transplantation Nov 2013An outbreak of 29 cases of Pneumocystis jirovecii pneumonia (PCP) occurred among renal and liver transplant recipients (RTR and LTR) in the largest Danish...
BACKGROUND
An outbreak of 29 cases of Pneumocystis jirovecii pneumonia (PCP) occurred among renal and liver transplant recipients (RTR and LTR) in the largest Danish transplantation centre between 2007 and 2010, when routine PCP prophylaxis was not used.
METHODS
P. jirovecii isolates from 22 transplant cases, 2 colonized RTRs, and 19 Pneumocystis control samples were genotyped by restriction fragment length polymorphism and multilocus sequence typing analysis. Contact tracing was used to investigate transmission. Potential risk factors were compared between PCP cases and matched non-PCP transplant patients.
RESULTS
Three unique Pneumocystis genotypes were shared among 19 of the RTRs, LTRs, and a colonized RTR in three distinct clusters, two of which overlapped temporally. In contrast, Pneumocystis control samples harbored a wide range of genotypes. Evidence of possible nosocomial transmission was observed. Among several potential risk factors, only cytomegalovirus viremia was consistently associated with PCP (P=0.03; P=0.009). Mycophenolate mofetil was associated with PCP risk only in the RTR population (P=0.04).
CONCLUSION
We identified three large groups infected with unique strains of Pneumocystis and provide evidence of an outbreak profile and nosocomial transmission. LTRs may be infected in PCP outbreaks simultaneously with RTRs and by the same strains, most likely by interhuman transmission. Patients are at risk several years after transplantation, but the risk is highest during the first 6 months after transplantation. Because patients at risk cannot be identified clinically and outbreaks cannot be predicted, 6 months of PCP chemoprophylaxis should be considered for all RTRs and LTRs.
Topics: Antifungal Agents; Contact Tracing; Cross Infection; Denmark; Disease Outbreaks; Drug Administration Schedule; Female; Genotype; Humans; Immunosuppressive Agents; Kidney Transplantation; Liver Transplantation; Male; Middle Aged; Phenotype; Pneumocystis carinii; Pneumonia, Pneumocystis; Retrospective Studies; Risk Assessment; Risk Factors; Time Factors
PubMed: 23903011
DOI: 10.1097/TP.0b013e3182a1618c -
Applied and Environmental Microbiology Nov 2012Bats belong to a wide variety of species and occupy diversified habitats, from cities to the countryside. Their different diets (i.e., nectarivore, frugivore,...
Bats belong to a wide variety of species and occupy diversified habitats, from cities to the countryside. Their different diets (i.e., nectarivore, frugivore, insectivore, hematophage) lead Chiroptera to colonize a range of ecological niches. These flying mammals exert an undisputable impact on both ecosystems and circulation of pathogens that they harbor. Pneumocystis species are recognized as major opportunistic fungal pathogens which cause life-threatening pneumonia in severely immunocompromised or weakened mammals. Pneumocystis consists of a heterogeneous group of highly adapted host-specific fungal parasites that colonize a wide range of mammalian hosts. In the present study, 216 lungs of 19 bat species, sampled from diverse biotopes in the New and Old Worlds, were examined. Each bat species may be harboring a specific Pneumocystis species. We report 32.9% of Pneumocystis carriage in wild bats (41.9% in Microchiroptera). Ecological and behavioral factors (elevation, crowding, migration) seemed to influence the Pneumocystis carriage. This study suggests that Pneumocystis-host association may yield much information on Pneumocystis transmission, phylogeny, and biology in mammals. Moreover, the link between genetic variability of Pneumocystis isolated from populations of the same bat species and their geographic area could be exploited in terms of phylogeography.
Topics: Animals; Carrier State; Chiroptera; Cluster Analysis; DNA, Fungal; DNA, Mitochondrial; DNA, Ribosomal; Genetic Variation; Lung; Molecular Sequence Data; Phylogeny; Pneumocystis; Pneumonia, Pneumocystis; Sequence Analysis, DNA
PubMed: 23001662
DOI: 10.1128/AEM.01791-12 -
Infection and Immunity May 2015Anti-CD20 antibody therapy has been a useful medication for managing non-Hodgkin's lymphoma as well as autoimmune diseases characterized by autoantibody generation. CD20...
Anti-CD20 antibody therapy has been a useful medication for managing non-Hodgkin's lymphoma as well as autoimmune diseases characterized by autoantibody generation. CD20 is expressed during most developmental stages of B lymphocytes; thus, CD20 depletion leads to B-lymphocyte deficiency. As the drug has become more widely used, there has been an increase in the number of case reports of patients developing Pneumocystis pneumonia. The role of anti-CD20 in Pneumocystis jirovecii infection is under debate due to the fact that most patients receiving it are on a regimen of multiple immunosuppressive medications. To address the specific role of CD20 depletion in host immunity against Pneumocystis, we examined a murine anti-CD20 depleting antibody. We demonstrated that anti-CD20 alone is permissive for Pneumocystis infection and that anti-CD20 impairs components of type II immunity, such as production of interleukin-4 (IL-4), IL-5, and IL-13 by whole-lung cells, in response to Pneumocystis murina. We also demonstrated that CD4(+) T cells from mice treated with anti-CD20 during Pneumocystis infection are incapable of mounting a protective immune response when transferred into Rag1(-/-) mice. Thus, CD20(+) cells are critical for generating protective CD4(+) T-cell immune responses against this organism.
Topics: Animals; CD4-Positive T-Lymphocytes; Disease Models, Animal; Disease Susceptibility; Immunologic Factors; Mice, Inbred C57BL; Pneumocystis; Pneumonia, Pneumocystis; Rituximab
PubMed: 25733518
DOI: 10.1128/IAI.03099-14 -
The Journal of Infectious Diseases May 2022We describe the prevalence of Pneumocystis jirovecii in mother-infant pairs of very low birth weight newborns <32 weeks gestation. Molecular and microscopic methods were...
We describe the prevalence of Pneumocystis jirovecii in mother-infant pairs of very low birth weight newborns <32 weeks gestation. Molecular and microscopic methods were used for detection of P. jirovecii in patients' specimens. Pneumocystis DNA was detected in 8 nasopharyngeal aspirates (14%) of 56 newborns and in 7 oral washes (21%) of 34 mothers. Pneumocystis detection immediately after birth suggests the possibility of its transplacental transmission. Compared to noncolonized infants, more frequent occurrence of bronchopulmonary dysplasia was seen in colonized infants (P = .02), suggesting a potential clinical importance of this pathogen in abnormal lung development.
Topics: Gestational Age; Humans; Infant; Infant, Newborn; Pneumocystis; Pneumocystis carinii; Pneumonia, Pneumocystis; Respiratory Distress Syndrome
PubMed: 33857302
DOI: 10.1093/infdis/jiab209