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Journal of Molecular Medicine (Berlin,... Oct 2023The transcription factor GATA2 is involved in human diseases ranging from hematopoietic disorders, to cancer, to infectious diseases. GATA2 is one of six GATA-family... (Review)
Review
The transcription factor GATA2 is involved in human diseases ranging from hematopoietic disorders, to cancer, to infectious diseases. GATA2 is one of six GATA-family transcription factors that act as pioneering transcription factors which facilitate the opening of heterochromatin and the subsequent binding of other transcription factors to induce gene expression from previously inaccessible regions of the genome. Although GATA2 is essential for hematopoiesis and lymphangiogenesis, it is also expressed in other tissues such as the lung, prostate gland, gastrointestinal tract, central nervous system, placenta, fetal liver, and fetal heart. Gene or transcriptional abnormalities of GATA2 causes or predisposes patients to several diseases including the hematological cancers acute myeloid leukemia and acute lymphoblastic leukemia, the primary immunodeficiency MonoMAC syndrome, and to cancers of the lung, prostate, uterus, kidney, breast, gastric tract, and ovaries. Recent data has also linked GATA2 expression and mutations to responses to infectious diseases including SARS-CoV-2 and Pneumocystis carinii pneumonia, and to inflammatory disorders such as atherosclerosis. In this article we review the role of GATA2 in the etiology and progression of these various diseases.
PubMed: 37624387
DOI: 10.1007/s00109-023-02359-8 -
Medical Mycology Sep 2023Pneumocystis jirovecii is a transmissible fungus responsible for severe pneumonia (Pneumocystis pneumonia [PCP]) in immunocompromised patients. Missense mutations due to... (Review)
Review
Pneumocystis jirovecii is a transmissible fungus responsible for severe pneumonia (Pneumocystis pneumonia [PCP]) in immunocompromised patients. Missense mutations due to atovaquone selective pressure have been identified on cytochrome b (CYB) gene of P. jirovecii. It was recently shown that atovaquone prophylaxis can lead to the selection of specific P. jirovecii CYB mutants potentially resistant to atovaquone among organ transplant recipients. In this context, our objectives were to provide data on P. jirovecii CYB mutants and the putative selective pressure exerted by atovaquone on P. jirovecii organisms in France. A total of 123 patients (124 P. jirovecii specimens) from four metropolitan hospitals and two overseas hospitals were retrospectively enrolled. Fourteen patients had prior exposure to atovaquone, whereas 109 patients did not at the time of P. jirovecii detection. A 638 base-pair fragment of the CYB gene of P. jirovecii was amplified and sequenced. A total of 10 single nucleotide polymorphisms (SNPs) were identified. Both missense mutations C431T (Ala144Val) and C823T (Leu275Phe), located at the Qo active site of the enzyme, were significantly associated with prior atovaquone exposure, these mutations being conversely incidental in the absence of prior atovaquone exposure (P < 0.001). Considering that the aforementioned hospitals may be representative of the national territory, these findings suggest that the overall presence of P. jirovecii CYB mutants remains low in France.
Topics: Animals; Pneumocystis carinii; Atovaquone; Cytochromes b; Retrospective Studies; Mutation
PubMed: 37656874
DOI: 10.1093/mmy/myad095 -
Clinical Microbiology and Infection :... Jul 2024Pneumocystis jirovecii pneumonia (PCP) is a common opportunistic infection among people living with HIV (PWH), particularly among new and untreated cases. Several... (Meta-Analysis)
Meta-Analysis Comparative Study Review
Comparative efficacy and safety of Pneumocystis jirovecii pneumonia prophylaxis regimens for people living with HIV: a systematic review and network meta-analysis of randomized controlled trials.
BACKGROUND
Pneumocystis jirovecii pneumonia (PCP) is a common opportunistic infection among people living with HIV (PWH), particularly among new and untreated cases. Several regimens are available for the prophylaxis of PCP, including trimethoprim-sulfamethoxazole (TMP-SMX), dapsone-based regimens (DBRs), aerosolized pentamidine (AP), and atovaquone.
OBJECTIVES
To compare the efficacy and safety of PCP prophylaxis regimens in PWH by network meta-analysis.
METHODS
DATA SOURCES: Embase, MEDLINE, and CENTRAL from inception to June 21, 2023.
STUDY ELIGIBILITY CRITERIA
Comparative randomized controlled trials (RCTs).
PARTICIPANTS
PWH.
INTERVENTIONS
Regimens for PCP prophylaxis either compared head-to-head or versus no treatment/placebo.
ASSESSMENT OF RISK OF BIAS
Cochrane risk-of-bias tool for RCTs 2.
METHODS OF DATA SYNTHESIS
Title or abstract and full-text screening and data extraction were performed in duplicate by two independent reviewers. Data on PCP incidence, all-cause mortality, and discontinuation due to toxicity were pooled and ranked by network meta-analysis. Subgroup analyses of primary versus secondary prophylaxis, by year, and by dosage were performed.
RESULTS
A total of 26 RCTs, comprising 55 treatment arms involving 7516 PWH were included. For the prevention of PCP, TMP-SMX was ranked the most favourable agent and was superior to DBRs (risk ratio [RR] = 0.54; 95% CI, 0.36-0.83) and AP (RR = 0.53; 95% CI, 0.36-0.77). TMP-SMX was also the only agent with a mortality benefit compared with no treatment/placebo (RR = 0.79; 95% CI, 0.64-0.98). However, TMP-SMX was also ranked as the most toxic agent with a greater risk of discontinuation than DBRs (RR = 1.25; 95% CI, 1.01-1.54) and AP (7.20; 95% CI, 5.37-9.66). No significant differences in PCP prevention or mortality were detected among the other regimens. The findings remained consistent within subgroups.
CONCLUSIONS
TMP-SMX is the most effective agent for PCP prophylaxis in PWH and the only agent to confer a mortality benefit; consequently, it should continue to be recommended as the first-line agent. Further studies are necessary to determine the optimal dosing of TMP-SMX to maximize efficacy and minimize toxicity.
Topics: Humans; Pneumonia, Pneumocystis; Randomized Controlled Trials as Topic; Network Meta-Analysis; Trimethoprim, Sulfamethoxazole Drug Combination; Pneumocystis carinii; HIV Infections; AIDS-Related Opportunistic Infections; Dapsone; Pentamidine; Atovaquone; Antifungal Agents; Treatment Outcome
PubMed: 38583518
DOI: 10.1016/j.cmi.2024.03.037 -
Current Opinion in Infectious Diseases Apr 2024This review highlights the epidemiology of Pneumocystis jirovecii pneumonia in solid organ transplant recipients, advancements in the diagnostic landscape, and updates... (Review)
Review
PURPOSE OF REVIEW
This review highlights the epidemiology of Pneumocystis jirovecii pneumonia in solid organ transplant recipients, advancements in the diagnostic landscape, and updates in treatment and prevention.
RECENT FINDINGS
The increasing use of immune-depleting agents in the context of solid organ transplantation has given rise to P. jirovecii pneumonia in this population. The use of prophylaxis has dramatically reduced risk of infection; however, late-onset infections occur after cessation of prophylaxis and in the setting of lymphopenia, advancing patient age, acute allograft rejection, and cytomegalovirus infection. Diagnosis requires respiratory specimens, with PCR detection of Pneumocystis replacing traditional staining methods. Quantitative PCR may be a useful adjunct to differentiate between infection and colonization. Metagenomic next-generation sequencing is gaining attention as a noninvasive diagnostic tool. Trimethoprim-sulfamethoxazole remains the drug of choice for treatment and prevention of Pneumocystis pneumonia. Novel antifungal agents are under investigation.
SUMMARY
P. jirovecii is a fungal opportunistic pathogen that remains a cause of significant morbidity and mortality in solid organ transplant recipients. Early detection and timely treatment remain the pillars of management.
Topics: Humans; Pneumocystis carinii; Pneumonia, Pneumocystis; Trimethoprim, Sulfamethoxazole Drug Combination; Organ Transplantation; Transplantation, Homologous; Transplant Recipients
PubMed: 38230604
DOI: 10.1097/QCO.0000000000001002 -
Chest Jun 2024Pneumocystis jirovecii pneumonia (PcP) remains associated with high rates of mortality, and the impact of immunocompromising underlying disease on the clinical... (Observational Study)
Observational Study
BACKGROUND
Pneumocystis jirovecii pneumonia (PcP) remains associated with high rates of mortality, and the impact of immunocompromising underlying disease on the clinical presentation, severity, and mortality of PcP has not been adequately evaluated.
RESEARCH QUESTION
Does the underlying disease and immunosuppression causing PcP impact the outcome and clinical presentation of the disease?
STUDY DESIGN AND METHODS
In this multicenter retrospective observational study, conducted from January 2011 to December 2021, all consecutive patients admitted with a proven or probable diagnosis of PcP according to the European Organisation for Research and Treatment of Cancer consensus definitions were included to assess the epidemiology and impact of underlying immunosuppressive diseases on overall and 90-day mortality.
RESULTS
Overall, 481 patients were included in the study; 180 (37.4%) were defined as proven PcP and 301 (62.6%) were defined as probable PcP. Patients with immune-mediated inflammatory diseases (IMIDs) or solid tumors had a statistically poorer prognosis than other patients with PcP at day 90. In multivariate analysis, among the HIV-negative population, solid tumor underlying disease (OR, 5.47; 95% CI, 2.16-14.1; P < .001), IMIDs (OR, 2.19; 95% CI, 1.05-4.60; P = .037), long-term corticosteroid exposure (OR, 2.07; 95% CI, 1.03-4.31; P = .045), cysts in sputum/BAL smears (OR, 1.92; 95% CI, 1.02-3.62; P = .043), and SOFA score at admission (OR, 1.58; 95% CI, 1.39-1.82; P < .001) were independently associated with 90-day mortality. Prior corticotherapy was the only immunosuppressant associated with 90-day mortality (OR, 1.67; 95% CI, 1.03-2.71; P = .035), especially for a prednisone daily dose ≥ 10 mg (OR, 1.80; 95% CI, 1.14-2.85; P = .010).
INTERPRETATION
Among patients who were HIV-negative, long-term corticosteroid prior to PcP diagnosis was independently associated with increased 90-day mortality, specifically in patients with IMIDs. These results highlight both the needs for PcP prophylaxis in patients with IMIDs and to early consider PcP curative treatment in severe pneumonia among patients with IMIDs.
Topics: Humans; Pneumonia, Pneumocystis; Male; Female; Retrospective Studies; Middle Aged; Prognosis; Aged; Pneumocystis carinii; Immunocompromised Host; Risk Factors
PubMed: 38215935
DOI: 10.1016/j.chest.2024.01.015 -
Antimicrobial Agents and Chemotherapy Mar 2024cyst life forms contain abundant β-glucan carbohydrates, synthesized using β-1,3 and β-1,6 glucan synthase enzymes and the donor uridine diphosphate (UDP)-glucose....
cyst life forms contain abundant β-glucan carbohydrates, synthesized using β-1,3 and β-1,6 glucan synthase enzymes and the donor uridine diphosphate (UDP)-glucose. In yeast, phosphoglucomutase (PGM) plays a crucial role in carbohydrate metabolism by interconverting glucose 1-phosphate and glucose 6-phosphate, a vital step in UDP pools for β-glucan cell wall formation. This pathway has not yet been defined in . Herein, we surveyed the and genomes, which predicted a homolog of the major PGM enzyme. Furthermore, we show that PjPgm2p and PmPgm2p function similarly to the yeast counterpart. When both homologs are heterologously expressed in cells, both genes can restore growth and sedimentation rates to wild-type levels. Additionally, we demonstrate that yeast cell lysates expressing the two transcripts individually can restore PGM activities significantly altered in the yeast strain. The addition of lithium, a competitive inhibitor of yeast PGM activity, significantly reduces PGM activity. Next, we tested the effects of lithium on viability and found the compound displays significant anti- activity. Finally, we demonstrate that a para-aryl derivative (ISFP10) with known inhibitory activity against the PGM protein and exhibiting 50-fold selectivity over the human PGM enzyme homolog can also significantly reduce Pmpgm2 activity . Collectively, our data genetically and functionally validate phosphoglucomutases in both and and suggest the potential of this protein as a selective therapeutic target for individuals with pneumonia.
Topics: Humans; Pneumocystis carinii; Pneumonia, Pneumocystis; Phosphoglucomutase; Saccharomyces cerevisiae; Lithium; Pneumocystis; beta-Glucans; Phosphates; Glucose; Uridine Diphosphate
PubMed: 38259086
DOI: 10.1128/aac.00756-23 -
BioRxiv : the Preprint Server For... Sep 2023spp. are host obligate fungal pathogens that can cause severe pneumonia in mammals and rely heavily on their host for essential nutrients. The lack of a sustainable...
spp. are host obligate fungal pathogens that can cause severe pneumonia in mammals and rely heavily on their host for essential nutrients. The lack of a sustainable culture system poses challenges in understanding their metabolism and the acquisition of essential nutrients from host lungs remains unexplored. Transmission electron micrographs show Extracellular Vesicles (EVs) are found near spp. within the lung. We hypothesized that EVs transport essential nutrients to the fungi during infection. To investigate this, EVs from and infected rodents were biochemically and functionally characterized. These EVs contained host proteins involved in cellular, metabolic, and immune processes as well as proteins with homologs found in other fungal EV proteomes, indicating may release EVs. Notably, EV uptake by indicated their potential involvement in nutrient acquisition and indicate a possibility for using engineered EVs for efficient therapeutic delivery. However, EVs added to , did not show increased growth or viability, implying that additional nutrients or factors are necessary to support their metabolic requirements. Exposure of macrophages to EVs increased proinflammatory cytokine levels, but did not affect macrophages' ability to kill or phagocytose . These findings provide vital insights into and host EV interactions, yet the mechanisms underlying 's survival in the lung remain uncertain. These studies are the first to isolate, characterize, and functionally assess EVs from -infected rodents, promising to enhance our understanding of host-pathogen dynamics and therapeutic potential.
PubMed: 37786700
DOI: 10.1101/2023.09.19.558454 -
Internal and Emergency Medicine Sep 2023The diagnosis of Pneumocystis jirovecii pneumonia (PCP) in patients presenting with severe pneumonia is challenging and delays in treatment were associated with worse... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
The diagnosis of Pneumocystis jirovecii pneumonia (PCP) in patients presenting with severe pneumonia is challenging and delays in treatment were associated with worse prognosis. This study aimed to develop a rapid, easily available, noninvasive machine learning diagnostic model for PCP among patients with severe pneumonia.
METHODS
A retrospective study was performed in West China Hospital among consecutive patients with severe pneumonia who had undergone bronchoalveolar lavage for etiological evaluation between October 2010 and April 2021. Factors associated with PCP were identified and four diagnostic models were established using machine learning algorithms including Logistic Regression, eXtreme Gradient Boosting, Random Forest (RF) and LightGBM. The performance of these models were evaluated by the area under the receiver operating characteristic curve (AUC).
RESULTS
Ultimately, 704 patients were enrolled and randomly divided into a training set (n = 564) and a testing set (n = 140). Four factors were ultimately selected to establish the model including neutrophil, globulin, β-D-glucan and ground glass opacity. The RF model exhibited the greatest diagnostic performance with an AUC of 0.907. The calibration curve and decision curve analysis also demonstrated its accuracy and applicability.
CONCLUSIONS
We constructed a PCP diagnostic model in patients with severe pneumonia using four easily available and noninvasive clinical indicators. With satisfying diagnostic performance and good clinical practicability, this model may help clinicians to make early diagnosis of PCP, reduce the delays of treatment and improve the prognosis among these patients.
Topics: Humans; Pneumonia, Pneumocystis; Pneumocystis carinii; Retrospective Studies; beta-Glucans; Bronchoalveolar Lavage
PubMed: 37530943
DOI: 10.1007/s11739-023-03353-1 -
Journal of Medical Case Reports Feb 2024Pneumocystis jirovecii (PJP) pneumonia is a serious life-threatening condition in immunocompromised individuals and is often associated with human immunodeficiency virus...
INTRODUCTION AND IMPORTANCE
Pneumocystis jirovecii (PJP) pneumonia is a serious life-threatening condition in immunocompromised individuals and is often associated with human immunodeficiency virus (HIV) + patients. We describe a case of PJP pneumonia which provided a diagnostic challenge in a patient who presented with no known risk factors leading to a delay in initiation of appropriate antibiotic therapy.
CASE PRESENTATION
A 71-year-old previously healthy white/Caucasian male presented with subacute hypoxic respiratory failure due to multifocal pneumonia with diffuse bilateral ground glass opacities with consolidations despite prior treatment with antibiotics and steroids. He was admitted and started on intravenous broad-spectrum antibiotics but continued to deteriorate, eventually requiring intubation and transfer to the ICU. Bronchoscopy revealed PJP and treatment was initiated, but the patient developed refractory shock and multiorgan failure, and ultimately died. It was later discovered that he was HIV-1 positive.
CLINICAL DISCUSSION
PJP, as a potential cause of his presentation, was not considered given that our patient lacked any overt risk factors for PJP pneumonia. He continued to worsen despite broad spectrum antibiotic therapy and hence bronchoscopy was pursued. His clinical profile, in hindsight, was suspicious for PJP pneumonia and early PJP-directed antibiotic therapy may have prevented a fatal outcome, as in this case. There was an element of cognitive bias across multiple providers which may have contributed to the delay in treatment despite his rapid clinical decline while on conventional pneumonia treatment protocol. His diagnosis was later evident when his BAL-DFA grew PJP in addition to his low levels of CD4 and CD8 cells. He was found to be HIV-1 positive five days after his death; there was a delay in this diagnosis since all positive HIV tests from the hospital are reported as 'pending' until the presumptive positive sample goes to the Connecticut Department of Public Health State laboratory for the confirmatory test. PJP-targeted therapies were initiated later in our patient's hospital course when the infection had progressed to refractory septic shock with multiorgan failure and eventual death.
CONCLUSION
PJP pneumonia is a fatal disease if not recognized early in the course of illness, and the patient usually undergoes multiple antibiotic regimens before they are diagnosed and receive appropriate clinical care. The gold standard of diagnostic testing for PJP is by obtaining bronchial washings through a flexible bronchoscopy and the turnaround time for such results may take a few days to result. A significant proportion of patients may not have any overt risk factors of immunosuppression and early empiric treatment for PJP may be clinically appropriate as the delay in diagnosis may be associated with significant morbidity and mortality risk.
Topics: Humans; Male; Aged; Pneumonia, Pneumocystis; Pneumocystis carinii; Risk Factors; Anti-Bacterial Agents; HIV Infections
PubMed: 38342895
DOI: 10.1186/s13256-024-04350-4 -
BMJ Case Reports May 2024A male patient in his 40s who had been unwell for months with fever of unknown origin and clinicopathological features suspicious for haemophagocytic lymphohistiocytosis...
A male patient in his 40s who had been unwell for months with fever of unknown origin and clinicopathological features suspicious for haemophagocytic lymphohistiocytosis presented to hospital with worsening subacute shortness of breath. CT pulmonary angiogram demonstrated ground glass changes involving all lung lobes with an apicobasal gradient. These changes, combined with long-term steroid exposure for granulomatous hepatitis without pneumocystis prophylaxis, raised concern for pneumocystis jirovecii pneumonia (PJP). A subsequent bronchoscopic lavage specimen was positive on PCR for PJP and the patient was started on appropriate therapy. Clinical and radiological changes initially improved but after completion of therapy, symptoms and radiological abnormalities returned. Retreatment with second-line treatment resulted again in initial improvement followed by relapse with acute deterioration. Further investigations for an alternate diagnosis were made, with a surgical lung biopsy performed finally revealing immunosuppression-related Epstein-Barr virus positive large B cell lymphoma with lymphomatoid granulomatosis of grade 3 pattern.
Topics: Humans; Lymphomatoid Granulomatosis; Male; Diagnosis, Differential; Adult; Pneumonia, Pneumocystis; Pneumocystis carinii; Tomography, X-Ray Computed; Lung
PubMed: 38821563
DOI: 10.1136/bcr-2024-259969