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Journal of Clinical Microbiology May 2022Pneumocystis pneumonia (PCP) caused by Pneumocystis jirovecii is a serious infection in immunocompromised hosts which requires prompt diagnosis and treatment. The...
Pneumocystis pneumonia (PCP) caused by Pneumocystis jirovecii is a serious infection in immunocompromised hosts which requires prompt diagnosis and treatment. The recommended specimen for diagnosis of PCP is bronchoalveolar lavage (BAL) fluid, which is invasive and may not be possible in unstable patients. The aim of this study was to evaluate the accuracy of noninvasive P. jirovecii plasma cell-free DNA (cfDNA) PCR using recently optimized preanalytical and analytical methods. Adult patients undergoing clinical testing for PCP with direct fluorescent antibody stain (DFA), respiratory PCR, and/or β-d-glucan were included in this study. Sensitivity and specificity P. jirovecii plasma cfDNA PCR was determined in PCP suspects categorized as proven and probable. A total of 149 patients were included in this study, of which 10 had proven and 27 had probable PCP. Most patients (95.9%, 143/149) were immunocompromised, including hematological malignancies (30.1%), bone marrow transplant (11.2%), solid organ transplantation (47.6%), and HIV/AIDS (4.2%). P. jirovecii plasma cfDNA PCR showed sensitivity and specificity of 100% (10/10; 95% confidence interval [CI], 69.2 to 100) and 93.4% (127/136; 95% CI, 87.8 to 96.9), and 48.6% (18/37; 95% CI, 31.9 to 65.6) and 99.1% (108/109; 95% CI, 94.9 to 100) in proven and proven/probable cases, respectively. P. jirovecii cell-free DNA PCR was similar in sensitivity but with substantially improved specificity over β-d-glucan (sensitivity, 60.0% [18/30; 95% CI, 40.6 to 77.3]); specificity, 66.7% [22/33; 95% CI, 48.2 to 82.0]) in patients with proven/probable PCP. Plasma cfDNA PCR offers a noninvasive testing option for early and accurate diagnosis of PCP, particularly in patients who cannot tolerate bronchoscopy.
Topics: Adult; Bronchoalveolar Lavage Fluid; Cell-Free Nucleic Acids; Glucans; Humans; Pneumocystis carinii; Pneumonia, Pneumocystis; Polymerase Chain Reaction; Sensitivity and Specificity
PubMed: 35387472
DOI: 10.1128/jcm.00101-22 -
European Journal of Pediatrics Dec 2017The aim of the study was to explore the frequency and dynamics of acquisition and colonization of Pneumocystis jirovecii among neonates, as well as the epidemiological...
UNLABELLED
The aim of the study was to explore the frequency and dynamics of acquisition and colonization of Pneumocystis jirovecii among neonates, as well as the epidemiological and genotypic characteristics in mother-child binomial. In a prospective enrolled cohort of women in their third trimester of pregnancy, nasopharyngeal swabs (NPS) and clinical and epidemiological data were collected at four different times: 17 days, 2nd, 4th, and 6th month of life of the newborn. P. jirovecii was detected by nested-PCR for the mtLSU-rRNA gene in each NPS; the genotypes were determined amplifying four genes. Forty-three pairs and 301 NPS were included. During the third trimester, 16.3% of pregnant women were colonized. The rate of colonization in mothers at delivery was 16, 6, 16, and 5% and in their children 28, 43, 42, and 25%, respectively. Within pregnant women, 53% remained negative throughout follow-up, and among these, 91% of their children were positive in at least one of their samples. In both, mothers and children, the most frequent genotype of P. jirovecii was 1.
CONCLUSION
The frequency of colonization by P. jirovecii was higher in newborns than in their respective progenitors. Colonization of both mothers and children is transitory; however, the mother of the newborn is not necessarily the source of primary infection. What is Known: • We did not find studies comparing P. jirovecii colonization between mothers and children simultaneously, yet the frequency of colonization by serologic and molecular methods in pregnant women has been reported. What is New: • According to our findings, 3/4 of the children had transient colonization during the first 6 months of life, in only half in the mothers, without proof of mother-to-child transmission or vice versa.
Topics: Adult; Colombia; Female; Follow-Up Studies; Genotype; Humans; Infant; Infant, Newborn; Infectious Disease Transmission, Vertical; Male; Pneumocystis carinii; Pneumonia, Pneumocystis; Prospective Studies
PubMed: 28913714
DOI: 10.1007/s00431-017-3011-z -
Clinical Laboratory Feb 2023Epstein-Barr virus (EBV) is the primary agent of infectious mononucleosis, lymphoma, and naso-pharyngeal carcinoma, but rarely involves the lungs. Pneumocystis carinii...
BACKGROUND
Epstein-Barr virus (EBV) is the primary agent of infectious mononucleosis, lymphoma, and naso-pharyngeal carcinoma, but rarely involves the lungs. Pneumocystis carinii is commonly found in patients with HIV infection and is not pathogenic when the host is healthy, but opportunistic infections can occur when the body is immunocompromised, causing pneumocystis pneumonia (PCP). It is rare for both diseases to occur in the lungs of the same patient.
METHODS
Next-generation sequencing (NGS), laboratory examination, chest CT scan, electronic bronchoscopy, and pathogenetic examination were used in this study.
RESULTS
Laboratory tests showed (1-3)-β-D-glucan of 889.47 pg/mL, negative human immunodeficiency virus (HIV) antibody, and negative Aspergillus immunological test. Chest CT showed multiple high-density shadows in both lungs, and EBV infection combined with Pneumocystis carinii pneumonia was confirmed by bronchoscopic biopsy and NGS examination.
CONCLUSIONS
Elevated serum (1-3)-β-D-glucan is not a specific index for infectious diseases. Bronchoscopy and the NGS has high specificity in pathogen detection of infectious diseases.
Topics: Humans; Pneumocystis carinii; Herpesvirus 4, Human; HIV Infections; Coinfection; Epstein-Barr Virus Infections; AIDS-Related Opportunistic Infections; Pneumonia, Pneumocystis; Lung; Carcinoma, Renal Cell; Kidney Neoplasms; Glucans
PubMed: 36787549
DOI: 10.7754/Clin.Lab.2022.220511 -
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 -
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 -
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 -
Medical Mycology Apr 2023Pneumocystis pneumonia (PCP) is the most frequent fungal opportunistic infection defining AIDS in HIV-infected patients, and is of growing importance in HIV-negative...
Evaluation of the PneumoGenius® PCR assay for the diagnosis of Pneumocystis pneumonia and the detection of Pneumocystis dihydropteroate synthase mutations in respiratory samples.
Pneumocystis pneumonia (PCP) is the most frequent fungal opportunistic infection defining AIDS in HIV-infected patients, and is of growing importance in HIV-negative patients. In this latter category of patients, the diagnosis mainly relies on real-time polymerase chain reaction (qPCR) detection of Pneumocystis jirovecii (Pj) on respiratory samples. The PneumoGenius® kit (PathoNostics) allows the simultaneous detection of Pj mitochondrial large subunit (mtLSU) and dihydropteroate synthase (DHPS) polymorphisms, which could be of interest to anticipate therapeutic failure. This study aimed at evaluating its clinical performance on 251 respiratory specimens (239 patients), (i) for P. jirovecii detection in clinical samples, and (ii) for DHPS polymorphisms detection in circulating strains. Patients were classified according to modified European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) criteria, as having proven PCP (n = 62), probable PCP (n = 87), Pneumocystis colonization (n = 37), and no PCP (n = 53). Compared with in-house qPCR, the sensitivity of PneumoGenius® assay for P. jirovecii detection reached 91.9% (182/198), the specificity was excellent (100%, 53/53) and the global concordance was 93.6% (235/253). A total of four diagnoses of proven/probable PCP were missed by the PneumoGenius® assay, reaching a 97.5% sensitivity (157/161) in this sub-group. The 12 other 'false-negative' results were obtained in patients diagnosed as colonized using the in-house PCR. DHPS genotyping was successful for 147/182 samples with PneumoGenius® and revealed dhps mutation in 8 samples, which were all confirmed by sequencing. In conclusion, PneumoGenius® assay missed the detection of low-burden PCP. This lower sensitivity for PCP diagnosis can be balanced by a higher specificity (P. jirovecii colonization less frequently detected) and the efficient detection of DHPS hot spot mutations.
Topics: Animals; Pneumonia, Pneumocystis; Pneumocystis; Dihydropteroate Synthase; Pneumocystis carinii; Mutation; Real-Time Polymerase Chain Reaction; HIV Infections
PubMed: 37028929
DOI: 10.1093/mmy/myad032 -
Journal de Mycologie Medicale Mar 2022To provide original data on Pneumocystis primary infection in non-immunosuppressed infants from Peru.
OBJECTIVES
To provide original data on Pneumocystis primary infection in non-immunosuppressed infants from Peru.
METHODS
A cross sectional study was performed. Infants less than seven months old, without any underlying medical conditions attending the "well baby" outpatient clinic at one hospital in Lima, Peru were prospectively enrolled during a 15-month period from November 2016 to February 2018. All had a nasopharyngeal aspirate (NPA) for detection of P. jirovecii DNA using a PCR assay, regardless of respiratory symptoms. P. jirovecii DNA detection was considered to represent pulmonary colonization contemporaneous with Pneumocystis primary infection. Associations between infants' clinical and demographic characteristics and results of P. jirovecii DNA detection were analyzed.
RESULTS
P. jirovecii DNA was detected in 45 of 146 infants (30.8%) and detection was not associated with concurrent respiratory symptoms in 40 of 45 infants. Infants with P. jirovecii had a lower mean age when compared to infants not colonized (p <0.05). The highest frequency of P. jirovecii was observed in 2-3-month-old infants (p < 0.01) and in the cooler winter and spring seasons (p <0.01). Multivariable analysis showed that infants living in a home with ≤ 1 bedroom were more likely to be colonized; Odds Ratio =3.03 (95%CI 1.31-7.00; p = 0.01).
CONCLUSION
Pneumocystis primary infection in this single site in Lima, Peru, was most frequently observed in 2-3-month-old infants, in winter and spring seasons, and with higher detection rates being associated with household conditions favoring close inter-individual contacts and potential transmission of P. jirovecii.
Topics: Cross-Sectional Studies; Humans; Infant; Peru; Pneumocystis; Pneumocystis carinii; Pneumonia, Pneumocystis
PubMed: 34598108
DOI: 10.1016/j.mycmed.2021.101202 -
Experimental Animals Feb 2022Pneumocystis (P.) carinii is known to cause fatal pneumonia in immunocompromised rats. Cases of P. carinii interstitial pneumonia in immunocompetent rats have been shown...
Pneumocystis (P.) carinii is known to cause fatal pneumonia in immunocompromised rats. Cases of P. carinii interstitial pneumonia in immunocompetent rats have been shown histologically to present with perivascular lymphoid cuffs, which have previously been attributed to rat respiratory virus. This study aims to determine the prevalence and pathological characteristics of P. carinii in immunocompetent laboratory rats in experimental facilities in Japan. An epidemiological survey for this agent was performed using PCR to assess 1,981 immunocompetent rats from 594 facilities in Japan. We observed that 6 of the 1,981 rats (0.30%) from 4 out of 594 facilities (0.67%) were positive for P. carinii without infection of other known pathogens. Gross pulmonary lesions were found in 4 of the 6 affected rats. The lungs of these rats contained scattered dark red/gray foci. Histopathologically, the lungs exhibited interstitial pneumonia with lymphoid perivascular cuffs: Pneumocystis cysts were observed using Grocott's methenamine silver stain. To our knowledge, this report is the first to reveal the prevalence of natural P. carinii infection in immunocompetent laboratory rats in Japan.
Topics: Animals; Lung; Lung Diseases, Interstitial; Pneumocystis; Pneumocystis carinii; Pneumonia, Pneumocystis; Rats
PubMed: 34511543
DOI: 10.1538/expanim.21-0091 -
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