-
Cellular Microbiology Oct 2020Caspase recruitment domains-containing protein 9 (CARD9) is an adaptor molecule critical for key signalling pathways initiated through C-type lectin receptors (CLRs)....
Caspase recruitment domains-containing protein 9 (CARD9) is an adaptor molecule critical for key signalling pathways initiated through C-type lectin receptors (CLRs). Previous studies demonstrated that Pneumocystis organisms are recognised through a variety of CLRs. However, the role of the downstream CARD9 adaptor signalling protein in host defence against Pneumocystis infection remains to be elucidated. Herein, we analysed the role of CARD9 in host defence against Pneumocystis both in CD4-depleted CARD9 and immunocompetent hosts. Card9 gene-disrupted (CARD9 ) mice were more susceptible to Pneumocystis, as evidenced by reduced fungal clearance in infected lungs compared to wild-type (WT) infected mice. Our data suggests that this defect was due to impaired proinflammatory responses. Furthermore, CARD9 macrophages were severely compromised in their ability to differentiate and express M1 and M2 macrophage polarisation markers, to enhanced mRNA expression for Dectin-1 and Mincle, and most importantly, to kill Pneumocystis in vitro. Remarkably, compared to WT mice, and despite markedly increased organism burdens, CARD9 animals did not exhibit worsened survival during pneumocystis pneumonia (PCP), perhaps related to decreased lung injury due to altered influx of inflammatory cells and decreased levels of proinflammatory cytokines in response to the organism. Finally, although innate phase cytokines were impaired in the CARD9 animals during PCP, T-helper cell cytokines were normal in immunocompetent CARD9 animals infected with Pneumocystis. Taken together, our data demonstrate that CARD9 has a critical function in innate immune responses against Pneumocystis.
Topics: Animals; CARD Signaling Adaptor Proteins; Cell Differentiation; Colony Count, Microbial; Cytokines; Immunocompromised Host; Lectins, C-Type; Lung; Macrophages, Alveolar; Membrane Proteins; Mice; Mice, Inbred C57BL; Mitogen-Activated Protein Kinases; Peroxidase; Pneumocystis; Pneumocystis carinii; Pneumonia, Pneumocystis; Rats; T-Lymphocytes, Helper-Inducer; Tumor Necrosis Factor-alpha
PubMed: 32548948
DOI: 10.1111/cmi.13235 -
Emerging Infectious Diseases Oct 2021Prophylactic trimethoprim/sulfamethoxazole (TMP/SMX) prevents Pneumocystis jirovecii pneumonia and nocardiosis in immunocompromised patients but sometimes is avoided...
Prophylactic trimethoprim/sulfamethoxazole (TMP/SMX) prevents Pneumocystis jirovecii pneumonia and nocardiosis in immunocompromised patients but sometimes is avoided because of purported allergies or side effects. Of 25 immunocompromised patients receiving alternative prophylaxis in whom nocardiosis developed, 16 subsequently tolerated TMP/SMX treatment. Clinicians should consider TMP/SMX allergy evaluation and rechallenging to assess patient tolerance.
Topics: Humans; Immunocompromised Host; Nocardia Infections; Pneumocystis; Pneumocystis carinii; Pneumonia, Pneumocystis; Retrospective Studies
PubMed: 34545802
DOI: 10.3201/eid2710.210620 -
International Journal of Infectious... Oct 2021Objectives To prospectively evaluate lung ultrasound in comparison with radiography and computed tomography (CT) for detecting HIV-related lung diseases. Methods...
Objectives To prospectively evaluate lung ultrasound in comparison with radiography and computed tomography (CT) for detecting HIV-related lung diseases. Methods Ultrasound examinations in HIV-positive patients were evaluated by three raters; available conventional imaging was evaluated by another rater. Results were compared with each other and the definite diagnosis. Interrater reliability was calculated for each finding. Results Eighty HIV-positive patients received lung ultrasound examinations; 74 received conventional imaging. The overall sensitivity was 97.5% for CT, 90.7% for ultrasound and 78.1% for radiography. The most common diagnoses were Pneumocystis jirovecii pneumonia (21 cases) and bacterial pneumonia (17 cases). The most frequent and sensitive ultrasonographic findings were interstitial abnormalities indicated by B-lines, independent of the aetiology. Interrater reliability was high for interstitial abnormalities (ICC=0.82). The interrater reliability for consolidations and effusion increased during the study (r=0.88 and r=0.37, respectively). Conclusions Ultrasound is a fast, reliable and sensitive point-of-care tool, particularly in detecting interstitial lung disease, which is common in HIV-associated illness. It does not effectively discriminate between different aetiologies. A longer learning period might be required to reliably identify consolidations and effusions.
Topics: HIV Infections; Humans; Lung; Lung Diseases, Interstitial; Pneumocystis carinii; Pneumonia, Pneumocystis; Reproducibility of Results; Ultrasonography
PubMed: 34407479
DOI: 10.1016/j.ijid.2021.08.030 -
PLoS Neglected Tropical Diseases Dec 2021Pneumocystis pneumonia (PCP) and pulmonary toxoplasmosis (PT) are caused by Pneumocystis jirovecii and Toxoplasma gondii. The clinical symptoms and imaging of PCP and PT...
Pneumocystis pneumonia (PCP) and pulmonary toxoplasmosis (PT) are caused by Pneumocystis jirovecii and Toxoplasma gondii. The clinical symptoms and imaging of PCP and PT are indistinguishable. A duplex qPCR was developed to differentiate between these two pathogens. In testing 92 clinical samples to validate the performance of this method for P. jirovecii detection, it identified 31 positive samples for P. jirovecii infection, consistent with clinical diagnosis. Among the remainder of the 61 clinical samples with suspected PCP, yet showing as negative by the conventional PCR diagnosis approach, 6 of them proved positive using our new assay. Our new approach also produced similar results in identification of T. gondii infections, giving a result of 2 positive and 20 negative in clinical samples. An investigation was undertaken on the prevalence of P. jirovecii and T. gondii infections using 113 samples from lung infection patients. 9% (10/113) were shown to be positive with infections of P. jirovecii, 2% with T. gondii (2/113) and 5% (6/113) were co-infected with both pathogens. Although this duplex qPCR can detect individual P. jirovecii and T. gondii infection, and co-infection of both pathogens, further large-scale investigations are needed to validate its performance, especially in T. gondii detection. Our assay provides a rapid and accurate tool for PCP and PT diagnosis in immunocompromised population and clinical surveillance of these infections in patients with no immune defects.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Female; Humans; Immunocompromised Host; Infant; Lung; Lung Diseases; Male; Middle Aged; Pneumocystis carinii; Pneumonia, Pneumocystis; Polymerase Chain Reaction; Toxoplasma; Toxoplasmosis; Young Adult
PubMed: 34919557
DOI: 10.1371/journal.pntd.0010025 -
BMC Infectious Diseases Jul 2019Pneumocystis jirovecii pneumonia (PCP) is one of the most common HIV-related opportunistic infections. The diagnosis of PCP is based on analyses from respiratory tract...
Serum-based diagnosis of Pneumocystis pneumonia by detection of Pneumocystis jirovecii DNA and 1,3-β-D-glucan in HIV-infected patients: a retrospective case control study.
BACKGROUND
Pneumocystis jirovecii pneumonia (PCP) is one of the most common HIV-related opportunistic infections. The diagnosis of PCP is based on analyses from respiratory tract specimens which may require the invasive procedure of a diagnostic bronchoscopy. The objective of this study was to evaluate the diagnostic potential of Pneumocystis jirovecii PCR in serum combined with the 1,3-β-D-glucan (betaglucan) test for the diagnosis of PCP in HIV-infected patients.
METHODS
This was a retrospective case-control study including serum samples from 26 HIV-infected patients with PCP collected within 5 days prior to the start of PCP treatment, 21 HIV-infected control subjects matched by blood CD4 cell counts, and 18 blood donors. The serum samples were analyzed for Pneumocystis jirovecii PCR and betaglucan. The reference standard for PCP was based on previously described microbiological and clinical criteria.
RESULTS
All patients with PCP had detectabe Pneumocystis jirovecii DNA in serum yielding a sensitivity for the Pneumocystis jirovecii PCR assay in serum of 100%. All blood donors had negative Pneumocystis PCR in serum. The specificity when testing HIV-infected patients was 71%, but with a PCR Cycle threshold (Ct) value of 34 as cut-off the specificity was 90%. At a putative pretest probaility of 20%, the negative and positive predictive value for the Pneumocystis PCR assay in serum was 0.99 and 0.71, respectively. Betaglucan with cut-off level 200 pg/ml combined with a positive Pneumocystis jirovecii PCR result had sensitivity and specificity of 92 and 90%, respectively. The concentration of Pneumocystis jirovecii DNA in serum samples, expressed by the PCR Ct values, correlated inversely to the betaglucan levels in serum.
CONCLUSION
In this case-control study including 70% of all HIV-infected patients with PCP treated at Sahlgrenska University Hospital during a time period of 13 years, Pneumocystis PCR analysis on serum samples had a very high sensitivity and negative predictive value for the diagnosis of PCP in HIV-infected patients. A serum-based diagnostic procedure either based on Pneumocystis jirovecii PCR alone or in combination with betaglucan analysis may thus be feasible and would facilitate the care of HIV-infected patients with suspected PCP.
Topics: AIDS-Related Opportunistic Infections; Adolescent; Adult; Aged; Blood Donors; Case-Control Studies; DNA, Fungal; Female; Humans; Male; Middle Aged; Pneumocystis carinii; Pneumonia, Pneumocystis; Polymerase Chain Reaction; Retrospective Studies; Sensitivity and Specificity; beta-Glucans
PubMed: 31337356
DOI: 10.1186/s12879-019-4289-4 -
BMC Infectious Diseases Nov 2023Droplet digital PCR (ddPCR) is a novel assay to detect pneumocystis jjrovecii (Pj) which has been defined to be more sensitive than qPCR in recent studies. We aimed to...
OBJECTIVE
Droplet digital PCR (ddPCR) is a novel assay to detect pneumocystis jjrovecii (Pj) which has been defined to be more sensitive than qPCR in recent studies. We aimed to explore whether clinical features of pneumocystis pneumonia (PCP) were associated with ddPCR copy numbers of Pj.
METHODS
A total of 48 PCP patients were retrospectively included. Pj detection was implemented by ddPCR assay within 4 h. Bronchoalveolar fluid (BALF) samples were collected from 48 patients with molecular diagnosis as PCP via metagenomic next generation sequencing (mNGS) or quantitative PCR detection. Univariate and multivariate logistic regression were performed to screen out possible indicators for the severity of PCP. The patients were divided into two groups according to ddPCR copy numbers, and their clinical features were further analyzed.
RESULTS
Pj loading was a pro rata increase with serum (1,3)-beta-D glucan, D-dimmer, neutrophil percentage, procalcitonin and BALF polymorphonuclear leucocyte percentage, while negative correlation with albumin, PaO2/FiO2, BALF cell count, and BALF lymphocyte percentage. D-dimmer and ddPCR copy number of Pj were independent indicators for moderate/severe PCP patients with PaO2/FiO2 lower than 300. We made a ROC analysis of ddPCR copy number of Pj for PaO2/FiO2 index and grouped the patients according to the cut-off value (2.75). The high copy numbers group was characterized by higher level of inflammatory markers. Compared to low copy number group, there was lower level of the total cell count while higher level of polymorphonuclear leucocyte percentage in BALF in the high copy numbers group. Different from patients with high copy numbers, those with high copy numbers had a tendency to develop more severe complications and required advanced respiratory support.
CONCLUSION
The scenarios of patients infected with high ddPCR copy numbers of Pj showed more adverse clinical conditions. Pj loading could reflect the severity of PCP to some extent.
Topics: Humans; Pneumonia, Pneumocystis; Retrospective Studies; DNA Copy Number Variations; Bronchoalveolar Lavage Fluid; Polymerase Chain Reaction; Pneumocystis; Respiratory Distress Syndrome; Pneumocystis carinii
PubMed: 38012564
DOI: 10.1186/s12879-023-08580-7 -
Annals of Clinical Microbiology and... Nov 2023The current study evaluated the diagnostic performance of serum (1,3)-beta-D Glucan (BDG) in differentiating PJP from P. jirovecii-colonization in HIV-uninfected...
OBJECTIVE
The current study evaluated the diagnostic performance of serum (1,3)-beta-D Glucan (BDG) in differentiating PJP from P. jirovecii-colonization in HIV-uninfected patients with P. jirovecii PCR-positive results.
METHODS
This was a single-center retrospective study between 2019 and 2021. The diagnosis of PJP was based on the following criteria: detection of P. jirovecii in sputum or BAL specimen by qPCR or microscopy; Meet at least two of the three criteria: (1) have respiratory symptoms of cough and/or dyspnea, hypoxia; (2) typical radiological picture findings; (3) receiving a complete PJP treatment. After exclusion, the participants were divided into derivation and validation cohorts. The derivation cohort defined the cut-off value of serum BDG. Then, it was verified using the validation cohort.
RESULTS
Two hundred and thirteen HIV-uninfected patients were enrolled, with 159 PJP and 54 P. jirovecii-colonized patients. BDG had outstanding specificity, LR, and PPV for PJP in both the derivation (90.00%, 8.900, and 96.43%) and the validation (91.67%, 9.176, and 96.30%) cohorts at ≥ 117.7 pg/mL. However, it had lower sensitivity and NPV in the derivation cohort (89.01% and 72.97%), which was even lower in the validation cohort (76.47% and 57.89%). Of note, BDG ≥ 117.7 pg/mL has insufficient diagnostic efficacy for PJP in patients with lung cancer, interstitial lung disease (ILD) and nephrotic syndrome. And although lymphocytes, B cells, and CD4 T cells in PJP patients were significantly lower than those in P. jirovecii-colonized patients, the number and proportion of peripheral blood lymphocytes did not affect the diagnostic efficacy of serum BDG.
CONCLUSIONS
Serum BDG ≥ 117.7 pg/mL could effectively distinguish P. jirovecii-colonization from infection in qPCR-positive HIV-uninfected patients with infectious diseases, solid tumors (excluding lung cancer), autoimmune or inflammatory disorders, and hematological malignancies. Of note, for patients with lung cancer, ILD, and nephrotic diseases, PJP should be cautiously excluded at BDG < 117.7 pg/mL.
Topics: Humans; Pneumonia, Pneumocystis; Pneumocystis carinii; Glucans; Retrospective Studies; beta-Glucans; Lung Neoplasms; HIV Infections; Lung Diseases, Interstitial
PubMed: 37986091
DOI: 10.1186/s12941-023-00650-7 -
MBio Jun 2018
Topics: DNA, Fungal; Humans; Pneumocystis carinii; Pneumonia, Pneumocystis; Respiratory System
PubMed: 29895638
DOI: 10.1128/mBio.00939-18 -
International Journal of Infectious... Sep 2022To investigate the clinical outcomes and risk factors of mortality in patients with rheumatic diseases complicated by Pneumocystis pneumonia (PCP).
OBJECTIVES
To investigate the clinical outcomes and risk factors of mortality in patients with rheumatic diseases complicated by Pneumocystis pneumonia (PCP).
METHODS
Between November 2015 and April 2021, patients with rheumatic diseases with PCP in a tertiary referral hospital were retrospectively enrolled. The diagnosis of PCP requires the fulfillment of clinical, radiographic, and microbiological criteria. Factors associated with in-hospital, 30-day, and 90-day mortality were evaluated.
RESULTS
A total of 128 patients with rheumatic diseases who had a positive quantitative polymerase chain reaction assay for Pneumocystis jirovecii were screened, and 72 patients were included in the final analysis. The median (interquartile range [IQR]) pneumonia severity index (PSI) was 101.5 (77.0-132.0). The median (IQR) adjunctive corticosteroid dosage was 0.6 (0.4-0.9) mg/kg/day prednisolone equivalent. The receiver operating characteristic curve analysis showed that the optimal cutoff point of median adjunctive corticosteroid dosage was 0.6 mg/kg/day to predict in-hospital, 30-day, and 90-day mortality. In the multivariable logistic regression analysis, median adjunctive corticosteroid dosage ≥0.6 mg/kg/day and PSI >90 were independent factors of in-hospital, 30-day, and 90-day mortality.
CONCLUSION
A median adjunctive corticosteroid dosage of ≥0.6 mg/kg/day might be associated with mortality in patients with rheumatic diseases complicated by PCP.
Topics: Adrenal Cortex Hormones; Humans; Pneumocystis carinii; Pneumonia, Pneumocystis; Prognosis; Retrospective Studies; Rheumatic Diseases
PubMed: 35918031
DOI: 10.1016/j.ijid.2022.07.070 -
Annals of Clinical Microbiology and... Jan 2024Pneumocystis jirovecii (P. jirovecii) is an opportunistic fungus responsible for Pneumocystis pneumonia (PCP) in deeply immunocompromised patients and for pulmonary...
BACKGROUND
Pneumocystis jirovecii (P. jirovecii) is an opportunistic fungus responsible for Pneumocystis pneumonia (PCP) in deeply immunocompromised patients and for pulmonary colonization in individuals with mild immunosuppression or impaired respiratory function. PCP and Cytomegalovirus (CMV) co-infections have been widely described whereas those involving other Herpesviruses (HVs) such as Epstein-Barr virus (EBV), Herpes simplex virus type 1 and type 2 (HSV-1 and -2), and Varicella zoster virus (VZV) remain scarce. To date, no data are available concerning HVs co-infections in P. jirovecii colonization.
METHODS
Our main objective was to evaluate the frequency of HVs in bronchoalveolar lavage fluid (BALF) samples from patients with PCP or with pulmonary colonization. The secondary objective was to assess the relationship between HVs and the mortality rate in PCP patients. A retrospective single-center study over a seven-year period was conducted. All patients with P. jirovecii detected using PCR in a BALF sample and for whom a PCR assay for HVs detection was performed were included in the study.
RESULTS
One hundred and twenty-five patients were included, corresponding to 77 patients with PCP and 48 colonized patients. At least one HV was detected in 54/77 (70.1%) PCP patients and in 28/48 (58.3%) colonized patients. EBV was the most frequent in both groups. Furthermore, the 30-day survival rate in PCP patients was significantly lower with [EBV + CMV] co-infection than that with EBV co-infection, [EBV + HSV-1] co-infection and without HV co-infection.
CONCLUSION
Our results show that the frequency of HV, alone or in combination is similar in PCP and colonization. They also suggest that [EBV + CMV] detection in BALF samples from PCP patients is associated with an increased mortality rate, underlying the significance to detect HVs in the course of PCP.
Topics: Humans; Pneumocystis carinii; Retrospective Studies; Pneumonia, Pneumocystis; Coinfection; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Herpesviridae; Cytomegalovirus Infections
PubMed: 38245721
DOI: 10.1186/s12941-023-00663-2