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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 -
The Canadian Journal of Neurological... Jul 2021
Topics: Humans; Immunocompromised Host; Neurosurgery; Pneumocystis carinii
PubMed: 33023676
DOI: 10.1017/cjn.2020.219 -
Medical Mycology Jan 2022Pneumocystis jirovecii (Pj) is a fungal pathogen that can cause severe and potential fatal pneumonia (Pneumocystis pneumonia, PCP) in immunocompromised patients....
UNLABELLED
Pneumocystis jirovecii (Pj) is a fungal pathogen that can cause severe and potential fatal pneumonia (Pneumocystis pneumonia, PCP) in immunocompromised patients. Microbiological diagnosis is necessary to confirm PCP, for which mainly real-time PCR assays are used by detecting Pj from bronchoalveolar lavage (BAL) specimens. In this study, we evaluate the performance of the CE-IVD PneumoGenius® assay and CE-IVD RealStar® Pneumocystis jirovecii PCR assay in comparison to the lab developed test (LDT) that is used in routine diagnostics. Comparison was done by including 100 BAL specimens: 25 retrospective specimens, selected based on results obtained with LDT (15 positive/10 negative), and 75 prospectively collected specimens. LDT (targeting MSG) was performed according to local procedures and the PneumoGenius® (targeting mtLSU and DHPS fas) and RealStar® assays (targeting mtLSU) according to the manufacturer's instructions. Combining results of retrospective and prospective analysis, sensitivity was 69.7, 100 and 100% for the LDT, PneumoGenius® and RealStar®, respectively. Specificity was 100% for LDT and Pneumogenius®, whereas RealStar® showed a specificity of 97%. Correlation of fungal loads found with the PneumoGenius® and RealStar® assays was high (R2: 0.98). The PneumoGenius® and RealStar® assays performed comparable, and both showed high sensitivity in comparison to the LDT. For optimal diagnosis of PCP, the LDT has to be replaced by another, more sensitive assay.
LAY SUMMARY
In this study, we evaluated the performance of two commercially available CE-IVD cleared real-time PCR assays to detect Pneumocystis jirovecii in comparison to the lab-developed test as used in routine diagnostics. Performance of the CE-IVD real-time PCR assay was superior to the lab-developed test.
Topics: Bronchoalveolar Lavage Fluid; Humans; Pneumocystis carinii; Pneumonia, Pneumocystis; Real-Time Polymerase Chain Reaction; Retrospective Studies; Sensitivity and Specificity
PubMed: 34894244
DOI: 10.1093/mmy/myab080 -
Medical Mycology Dec 2021Pneumocystis jirovecii colonization is frequent during chronic obstructive pulmonary disease (COPD) and patients constitute potential contributors to its interhuman...
Factors associated with Pneumocystis colonization and circulating genotypes in chronic obstructive pulmonary disease patients with acute exacerbation or at stable state and their homes.
UNLABELLED
Pneumocystis jirovecii colonization is frequent during chronic obstructive pulmonary disease (COPD) and patients constitute potential contributors to its interhuman circulation. However, the existence of an environmental reservoir cannot be excluded. We assessed the prevalence and factors associated with Pneumocystis colonization during COPD, and studied circulation between patients and their domestic environment. Pneumocystis molecular detection and mtLSU genotyping were performed in oro-pharyngeal washes (OPW) sampled in 58 patients with COPD acute exacerbation, and in indoor dust, sampled in patients' homes using electrostatic dust collectors (EDCs). Lung and systemic inflammation was assessed. Pneumocystis carriage was evaluated in 28 patients after 18 months at stable state. Pneumocystis was detected in 11/58 OPWs during exacerbation (19.0%). Colonized patients presented a significantly lower body mass index, and higher serum IL-17 and CD62P. One patient presented positive detection of typable isolates in both OPW and EDC, with both isolates harboring mtLSU genotype 3. Pneumocystis genotype 1 was further detected in EDCs from three non-colonized patients and one colonized patient with non-typable isolate. Genotypes 1 and 2 were predominant in clinical isolates (both 42%), with genotype 3 representing 16% of isolates. Pneumocystis was detected in 3/28 patients at stable state (10.7%). These data suggest that Pneumocystis colonization could be facilitated by a lower BMI and be related to acute alteration of lung function during COPD exacerbation. It also suggests Th17 pathway and platelet activation could be involved in the anti-Pneumocystis response during colonization. Last, Pneumocystis detection in EDCs supports its potential persistence in indoor dust.
LAY SUMMARY
Chronic obstructive pulmonary disease patients tend to be more frequently colonized by Pneumocystis during exacerbation (19.0%) than at stable state (10.7%). Factors associated with colonization include lower BMI, higher IL-17, and CD62P. Pneumocystis detection in patients' dwellings suggests potential persistence in indoor dust.
Topics: Genotype; Home Environment; Humans; Pneumocystis carinii; Pneumonia, Pneumocystis; Pulmonary Disease, Chronic Obstructive
PubMed: 34734270
DOI: 10.1093/mmy/myab070 -
Medical Mycology Nov 2017Pneumocystis pneumonia (PCP) is a life-threatening fungal disease that can occur in dogs. The aim of this study was to provide a preliminary genetic characterisation of...
Pneumocystis pneumonia (PCP) is a life-threatening fungal disease that can occur in dogs. The aim of this study was to provide a preliminary genetic characterisation of Pneumocystis carinii f.sp.'canis' (P. canis) in dogs and thereby develop a reliable molecular protocol to definitively diagnose canine PCP. We investigated P. canis in a variety of lung specimens from dogs with confirmed or strongly suspected PCP (Group 1, n = 16), dogs with non-PCP lower respiratory tract problems (Group 2, n = 65) and dogs not suspected of having PCP or other lower respiratory diseases (Group 3, n = 11). Presence of Pneumocystis DNA was determined by nested PCR of the large and small mitochondrial subunit rRNA loci and by a real-time quantitative polymerase chain reaction (qPCR) assay developed using a new set of primers. Molecular results were correlated with the presence of Pneumocystis morphotypes detected in cytological/histological preparations. Pneumocystis DNA was amplified from 13/16 PCP-suspected dogs (Group 1) and from 4/76 dogs of control Groups 2 and 3 (combined). The latter four dogs were thought to have been colonized by P. canis. Comparison of CT values in 'infected' versus 'colonized' dogs was consistent with this notion, with a distinct difference in molecular burden between groups (CT ≤ 26 versus CT range (26
Pneumocystis species, thereby confirming the accuracy of qPCR amplicon for Pneumocystis in dogs. Using qPCR, Pneumocystis DNA can be detected in specimens from the respiratory tract and a CT value can be interpreted to distinguish infection versus colonization. Topics: Animals; Bronchoalveolar Lavage Fluid; DNA Primers; DNA, Fungal; Dog Diseases; Dogs; Lung; Mycological Typing Techniques; Phylogeny; Pneumocystis carinii; Pneumonia, Pneumocystis; RNA; RNA, Mitochondrial; Real-Time Polymerase Chain Reaction; Sensitivity and Specificity
PubMed: 28339756
DOI: 10.1093/mmy/myx007 -
Frontiers in Immunology 2021is one of the most common fungal pathogens in immunocompromised individuals. Pneumocystis jirovecii pneumonia (PJP) causes a significant host immune response that is... (Review)
Review
is one of the most common fungal pathogens in immunocompromised individuals. Pneumocystis jirovecii pneumonia (PJP) causes a significant host immune response that is driven greatly by the organism's cell wall components including β-glucans and major surface glycoprotein (Msg). These ligands interact with a number of C-type lectin receptors (CLRs) leading to downstream activation of proinflammatory signaling pathways. This minireview provides a brief overview summarizing known CLR/ interactions.
Topics: Animals; Fungal Proteins; Host-Pathogen Interactions; Humans; Immunity, Innate; Inflammation Mediators; Lectins, C-Type; Ligands; Membrane Glycoproteins; Pneumocystis carinii; Pneumonia, Pneumocystis; Signal Transduction; beta-Glucans
PubMed: 34975910
DOI: 10.3389/fimmu.2021.798214 -
The Journal of Eukaryotic Microbiology May 2016To quantitatively assess the risk of contamination by Pneumocystis depending on the degree of immunosuppression (ID) of the exposed rat hosts, we developed an animal...
To quantitatively assess the risk of contamination by Pneumocystis depending on the degree of immunosuppression (ID) of the exposed rat hosts, we developed an animal model, where rats went through different doses of dexamethasone. Then, natural and aerial transmission of Pneumocystis carinii occurred during cohousing of the rats undergoing gradual ID levels (receivers) with nude rats developing pneumocystosis (seeders). Following contact between receiver and seeder rats, the P. carinii burden of receiver rats was determined by toluidine blue ortho staining and by qPCR targeting the dhfr monocopy gene of this fungus. In this rat model, the level of circulating CD4(+) and CD8(+) T lymphocytes remained significantly stable and different for each dose of dexamethasone tested, thus reaching the goal of a new stable and gradual ID rat model. In addition, an inverse relationship between the P. carinii burden and the level of circulating CD4(+) or CD8(+) T lymphocytes was evidenced. This rat model may be used to study other opportunistic pathogens or even co-infections in a context of gradual ID.
Topics: Aerosols; Air Microbiology; Animals; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Colony Count, Microbial; Dexamethasone; Disease Models, Animal; Genes, Fungal; Immunocompromised Host; Lung; Male; Pneumocystis carinii; Pneumonia, Pneumocystis; Rats
PubMed: 26509699
DOI: 10.1111/jeu.12280 -
Revista Da Sociedade Brasileira de... 2023
Topics: Humans; Pneumonia, Pneumocystis; Risk Factors; Adrenal Cortex Hormones; Pneumocystis carinii
PubMed: 36820664
DOI: 10.1590/0037-8682-0553-2022 -
Medical Mycology Sep 2021We conducted a pilot study of patients with cystic fibrosis (CF) to assess intra-family transmission of P. jirovecii and compare it with data on other prevalent... (Comparative Study)
Comparative Study Observational Study
UNLABELLED
We conducted a pilot study of patients with cystic fibrosis (CF) to assess intra-family transmission of P. jirovecii and compare it with data on other prevalent pathogens such as P. aeruginosa and S. pneumoniae, in which respiratory transmission has already been documented. Oral swab samples from 10 patients with CF and 15 household members were collected at baseline and 2 weeks later. P. aeruginosa and S. pneumoniae were assessed using standardized culture methods and PCR, and P. jirovecii was assessed using real and nested PCR, genotyping the positive samples by direct sequencing. P. aeruginosa cultures were positive for 7/10 (70%) of patients with CF at baseline and was identified by PCR in 8/10 (80%) of cases at baseline and 2 weeks later. S. pneumoniae cultures were negative for all patients, but the microorganism was identified by PCR in two cases. P. jirovecii was detected by real time and nested PCR in 5/10 (50%) of the patients at the two time points. In the household members, P. aeruginosa and P. jirovecii were identified in 7/15 (46.7%), and S. pneumoniae was identified in 8/15 (53,3%). The concordance of positive or negative pairs of patients with CF and their household members was 33.3% (5/15) for P. aeruginosa, 46.7% (7/15) for S. pneumonia and 93.3% (14/15) for P. jirovecii. The concordance for P. jirovecii genotypes among five pairs with available genotype was 100%. This study suggests for the first time the possible transmission of Pneumocystis in the home of patients with CF, indicating that patients and their household members are reservoirs and possible sources of infection.
LAY SUMMARY
This study suggests for the first time the possible transmission of Pneumocystis in the family environment of patients with cystic fibrosis, indicating that patients and their household members are reservoirs and possible sources of this infection.
Topics: Adolescent; Adult; Child; Cystic Fibrosis; Family Characteristics; Female; Genotype; Humans; Infectious Disease Transmission, Vertical; Male; Pilot Projects; Pneumococcal Infections; Pneumocystis carinii; Pneumonia, Pneumocystis; Polymerase Chain Reaction; Pseudomonas Infections; Pseudomonas aeruginosa; Streptococcus pneumoniae; Young Adult
PubMed: 33693837
DOI: 10.1093/mmy/myab010 -
Annals of Laboratory Medicine Mar 2019Real-time PCR is more sensitive than microscopic examination for detecting . We compared the performance of two assays for detecting DNA: the RealStar PCR Kit 1.0 CE... (Comparative Study)
Comparative Study
BACKGROUND
Real-time PCR is more sensitive than microscopic examination for detecting . We compared the performance of two assays for detecting DNA: the RealStar PCR Kit 1.0 CE (Altona Diagnostics, Hamburg, Germany) and the AmpliSens ()-FRT PCR kit (InterLabService Ltd., Moscow, Russia).
METHODS
We used 159 samples from the lower respiratory tract (112 bronchoalveolar lavage [BAL] fluid, 37 sputum, and 10 endotracheal aspirate [ETA] samples) of non-HIV immunocompromised patients. Nested PCR and sequencing were used to resolve discordant results. The performance of the two assays was evaluated according to clinical categories (clinical pneumonia [PCP], possible PCP, or unlikely PCP) based on clinical and radiological observations.
RESULTS
The positive and negative percent agreement values were 100% (95% confidence interval [CI], 85.4-100%) and 96.6% (95% CI, 90.9-98.9%), respectively, and kappa was 0.92 (95% CI, 0.84-0.99). DNA load was significantly higher in the clinical PCP group than in the other groups (<0.05). When stratified by sample type, the positive rate for BAL fluids from the clinical PCP group was 100% using either assay, whereas the positive rate for sputum/ETA samples was only 20%.
CONCLUSIONS
The two assays showed similar diagnostic performance and detected low burden in BAL fluids. Both assays may be useful as routine methods for detecting DNA in a clinical laboratory setting, though their results should be interpreted considering sample type.
Topics: Bronchoalveolar Lavage Fluid; DNA, Bacterial; Diagnostic Errors; Humans; Immunocompromised Host; Pneumocystis Infections; Pneumocystis carinii; Reagent Kits, Diagnostic; Real-Time Polymerase Chain Reaction; Respiratory Tract Diseases; Sputum
PubMed: 30430780
DOI: 10.3343/alm.2019.39.2.176