Risk factors and multi-pathogen infections in kidney transplant recipients with omicron variant pneumonia: a retrospective analysis.

BACKGROUND: Kidney transplant recipients (KTRs) are at an elevated risk of progressing to severe infections upon contracting COVID-19. We conducted a study on risk factors and multi-pathogen infections in KTRs with SARS-CoV-2 Omicron variant. METHODS: KTRs were subjected to a thorough etiological evaluation. Whenever feasible, they were also provided with bronchoscopy and bronchoalveolar lavage to enable metagenomic next-generation sequencing (mNGS), ideally within a 48-hour window post-admission. We performed a retrospective analysis for pathogens and risk factors of KTRs with the COVID-19 virus variant Omicron. RESULTS: We included thirty patients in our study, with sixteen exhibiting single infection of COVID-19 and fourteen experiencing co-infections, predominantly with Pneumocystis jirovecii. Notably, patients with severe cases demonstrated significantly elevated levels of C-reactive protein (CRP) and interleukin-6 compared to those with moderate cases (P < 0.05). Furthermore, individuals whose conditions progressed had markedly higher baseline serum creatinine levels than those without such progression (P < 0.05). The presence of heart failure, acute exacerbation of renal dysfunction, and a history of opportunistic infections were significantly associated with a higher likelihood of deterioration and hospital admission due to the SARS-CoV-2 Omicron variant, as compared to the control group (P < 0.05). In subsequent follow-up analysis, the all-cause rehospitalization rate was observed to be 21.4%, with Pneumocystis jirovecii infection accounting for half of these cases. CONCLUSION: Among KTRs, a significant coinfection rate of 47% was observed, with Pneumocystis jirovecii emerging as the predominant pathogen in these cases. The development of heart failure, acute exacerbation of chronic renal dysfunction, and a prior history of opportunistic infections have been identified as potential risk factors that may contribute to clinical deterioration in KTRs. Additionally, Pneumocystis jirovecii infection has been established as a critical factor influencing the rate of all-cause rehospitalization within this patient population.

Pneumocystis jirovecii Pneumonia Secondary to Blinatumomab Therapy: A Case Report.

INTRODUCTION: With the increasing use of blinatumomab in relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL), including minimal residual disease (MRD)-positive cases, awareness of its adverse effects has gradually improved. Pneumocystis jirovecii pneumonia (PCP) associated with blinatumomab therapy is rare. CASE PRESENTATION: We present a case of PCP in a patient undergoing blinatumomab therapy. A 70-year-old female diagnosed with Philadelphia-like CRLF2 overexpression B-cell precursor ALL received blinatumomab as consolidation therapy after achieving complete remission with prior induction chemotherapy. On the second day of blinatumomab infusion, she developed intermittent low-grade fever, and chest computed tomography (CT) revealed subtle infiltrates and nodules. Despite empiric trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis, she progressed to significant shortness of breath and type I respiratory failure, with increased lactate dehydrogenase and ß-D-glucan assays. Chest CT showed diffuse ground-glass opacities with scattered small nodules. The dry cough prompted next-generation sequencing of peripheral blood, which tested positive for pneumocystis jirovecii without evidence of other pathogens. Consequently, the patient was diagnosed with PCP. The first cycle of blinatumomab had to be discontinued, and therapeutic dosages of TMP-SMX and dexamethasone were administered, resulting in full recovery and stable condition during follow-ups. CONCLUSION: PCP is rare in B-cell precursor ALL patients receiving blinatumomab therapy but manifests with early onset and rapid disease progression. Despite prophylaxis, PCP infection cannot be ignored during blinatumomab therapy. Therefore, heightened attention is warranted when using blinatumomab therapy.

Diagnosis model of early Pneumocystis jirovecii pneumonia based on convolutional neural network: a comparison with traditional PCR diagnostic method.

BACKGROUND: Pneumocystis jirovecii pneumonia (PJP) is an interstitial pneumonia caused by pneumocystis jirovecii (PJ). The diagnosis of PJP primarily relies on the detection of the pathogen from lower respiratory tract specimens. However, it faces challenges such as difficulty in obtaining specimens and low detection rates. In the clinical diagnosis process, it is necessary to combine clinical symptoms, serological test results, chest Computed tomography (CT) images, molecular biology techniques, and metagenomics next-generation sequencing (mNGS) for comprehensive analysis. PURPOSE: This study aims to overcome the limitations of traditional PJP diagnosis methods and develop a non-invasive, efficient, and accurate diagnostic approach for PJP. By using this method, patients can receive early diagnosis and treatment, effectively improving their prognosis. METHODS: We constructed an intelligent diagnostic model for PJP based on the different Convolutional Neural Networks. Firstly, we used the Convolutional Neural Network to extract CT image features from patients. Then, we fused the CT image features with clinical information features using a feature fusion function. Finally, the fused features were input into the classification network to obtain the patient's diagnosis result. RESULTS: In this study, for the diagnosis of PJP, the accuracy of the traditional PCR diagnostic method is 77.58%, while the mean accuracy of the optimal diagnostic model based on convolutional neural networks is 88.90%. CONCLUSION: The accuracy of the diagnostic method proposed in this paper is 11.32% higher than that of the traditional PCR diagnostic method. The method proposed in this paper is an efficient, accurate, and non-invasive early diagnosis approach for PJP.

A combined immune and inflammatory indicator predict the prognosis of severe Pneumocystis jirovecii pneumonia patients: a 12-year, retrospective, observational cohort.

Persistent inflammatory damage and suppressed immune function play a crucial role in the pathogenesis and progression of the pneumocystis jirovecii pneumonia (PjP). Therefore, we aimed to investigate the correlation between the combined immune and inflammatory indicator: the neutrophil-to-lymphocyte ratio (NLR) and prognosis of non-human immunodeficiency virus (non-HIV) PjP.In the retrospective analysis conducted in ICUs at Beijing Chao-Yang Hospital, we examined data from 157 patients diagnosed with non-HIV PjP. Our findings reveal a concerning hospital mortality rate of 43.3%, with the 28-day mortality rate reaching 47.8%.Through multivariable logistic and Cox regression analyses, we established a significant association between elevated NLR levels and hospital mortality (adjusted odd ratio, 1.025; 95% CI, 1.008-1.043; p = 0.004) or 28-day mortality (adjusted hazard ratio, 1.026; 95% CI, 1.008-1.045; p = 0.005). Specifically, patients with an NLR exceeding 20.3 demonstrated markedly lower overall survival rates, underscoring the biomarker's predictive value for both hospital and 28-day mortality.In conclusion, non-HIV PjP patients in the ICU still have a high rate of mortality and a poor short-term prognosis after discharge. A high level of NLR was associated with an increased risk of hospital mortality and 28-day mortality.

A case of hypercalcemia from Pneumocystis jirovecii in an immunosuppressed non-HIV patient.

BACKGROUND: The prevalence of non-HIV related Pneumocystis jirovecii pneumonia (PJP) is increasing with use of immunosuppressive therapies. There are case reports of solid organ transplant recipients on immunosuppressive therapy presenting with mild hypercalcemia, leading to a diagnosis of PJP. Recent studies have shown efficacy of PJP prophylaxis for patients treated with rituximab with a favourable adverse effect profile. CASE PRESENTATION: A 78-year-old male with a history of PR3-ANCA vasculitis, chronic kidney disease and heart failure with reduced ejection fraction presented to our tertiary care hospital with a two-week history of confusion and non-productive cough. Background immunosuppression with rituximab was completed every six months. The patient was found to have hypercalcemia and new infiltrates and ground glass opacities on cross-sectional imaging. Bronchoscopy was performed that was positive for Pneumocystis jirovecii. He was treated with 21 days of trimethoprim-sulfamethoxazole and prednisone with resolution of symptoms and hypercalcemia. CONCLUSIONS: Herein, we present a novel case of PJP in a non-transplant recipient preceded by hypercalcemia. Our case demonstrates the importance for a high suspicion for PJP in chronically immunosuppressed patients on rituximab presenting with PTH-independent hypercalcemia.

Rapid Diagnosis of Pneumocystis jirovecii Pneumonia and Respiratory Tract Colonization by Next-Generation Sequencing.

OBJECTIVES: To describe the epidemiology of Pneumocystis jirovecii pneumonia and colonization diagnosed by next-generation sequencing (NGS) and explore the usefulness of the number of P. jirovecii sequence reads for the diagnosis of P. jirovecii pneumonia. METHODS: We examined the NGS results for P. jirovecii in respiratory samples collected from patients and analysed their clinical, radiological and microbiological characteristics. RESULTS: Among 285 respiratory samples collected over a 12-month period (January to December 2022), P. jirovecii sequences were detected in 56 samples from 53 patients. Fifty (94.3%) of the 53 patients were HIV-negative. Following our case definitions, 37 (69.8%) and 16 (30.2%) of the 53 patients had P. jirovecii infection and colonization respectively. P. jirovecii infection was associated with presence of underlying disease with immunosuppression (94.6% vs 18.8%, P < 0.05), positive serum 1,3-ß-D-glucan (41.2% vs 0%, P < 0.01) and higher number of P. jirovecii sequence reads (P < 0.005). In contrast, P. jirovecii colonization was associated with the male sex (93.8% vs 54.1%, P < 0.01), another definitive infectious disease diagnosis of the respiratory tract (43.8% vs 2.7%, P < 0.001) and higher survival (100% vs 67.6%, P < 0.01). Although P. jirovecii pneumonia was associated with higher number of P. jirovecii reads in respiratory samples, only a sensitivity of 82.14% and a specificity of 68.75% could be achieved. CONCLUSION: Detection of P. jirovecii sequences in respiratory samples has to be interpreted discreetly. A combination of clinical, radiological and laboratory findings is still the most crucial in determining whether a particular case is genuine P. jirovecii pneumonia.

Clinical characteristics and risk factors associated with Pneumocystis jirovecii infection in patients with solid tumors: study of thirteen-year medical records of a large cancer center.

BACKGROUND: Pneumocystis jirovecii pneumonia (PCP)-related risk factors among patients with solid tumors are not completely defined. Thus, we aimed to characterize PCP cases with underlying solid tumors, to highlight the factors contributing to its development besides the prolonged use of moderate-to-high dose corticosteroids. METHODS: We retrospectively reviewed the medical records of patients with solid tumors diagnosed with PCP between 2006 and 2018 at a cancer center in Tokyo, Japan. Demographic and clinical data were collected, which included malignancy types, total lymphocyte count, coexisting pulmonary disease, chemotherapy, radiation therapy, corticosteroid use, and PCP-attributable mortality. RESULTS: Twenty cases of PCP with solid tumors were documented in 151,718 patients and 788,914 patient-years. Lung cancer (n = 6, 30%) was the most common underlying tumor, followed by breast cancer (n = 3, 15%). Only six (30%) patients were taking a dosage of ≥20 mg prednisone equivalents daily for ≥4 weeks from the onset of PCP. Among the remaining 14 patients, seven (50%) had coexisting pulmonary diseases, 10 (71%) had received chemotherapy within 90 days prior to PCP diagnosis, seven (50%) had undergone chest radiation therapy before PCP diagnosis, seven (50%) had received only intermittent corticosteroids, and one (7%) received no corticosteroids. Mortality attributable to PCP was 40%. CONCLUSIONS: More than half of the patients were not taking a dosage of ≥20 mg prednisone equivalents daily for ≥4 weeks. Multiple other factors (e.g., lymphocytopenia, radiation to chest) may have potentially contributed to PCP in patients with solid tumors in a composite manner. We need to establish a method for estimating the likelihood of PCP taking multiple factors into account in this patient population.

Increased sensitivity of a new commercial reverse transcriptase-quantitative PCR for the detection of Pneumocystis jirovecii in respiratory specimens.

Optimal sensitivity to detect low Pneumocystis loads is of importance to take individual and collective measures to avoid evolution towards Pneumocystis pneumonia and outbreaks in immunocompromised patients. This study compares two qPCR procedures, a new automated RTqPCR using the GeneLEAD VIII extractor/thermocycler (GLVIII; ∼2.2 h workflow) and a previously validated in-house qPCR assays (IH; ∼5 h workflow) both targeting mtSSU and mtLSU for detecting P. jirovecii in 213 respiratory samples. GLVIII was found to be more sensitive than IH, detecting eight more specimens. Bland-Altman analysis between the two procedures showed a Cq bias of 1.17 ± 0.07 in favor of GLVIII. LAY SUMMARY: The fungus Pneumocystis needs to be detected early in respiratory samples to prevent pneumonia in immunocompromised hosts. We evaluated a new commercial RTqPCR on 213 respiratory samples to detect Pneumocystis and found it more sensitive and faster than our routine sensitive in-house qPCR assay.

The prevalence of laboratory-confirmed Pneumocystis jirovecii in HIV-infected adults in Africa: A systematic review and meta-analysis.

BACKGROUND: The epidemiology of Pneumocystis jirovecii, known to colonize the respiratory tract and cause a life-threatening HIV-associated pneumonia (PCP), is poorly described in Africa. We conducted a systematic review to evaluate P. jirovecii prevalence in African HIV-positive adults with or without respiratory symptoms. METHODS: We searched Medline, Embase, Cochrane library, Africa-Wide, and Web of Science for studies employing PCR and/or microscopy for P. jirovecii detection in respiratory samples from HIV-positive adults in Africa between 1995 and 2020. Prevalence with respiratory symptoms was pooled using random-effect meta-analysis, and stratified by laboratory method, sample tested, study setting, CD4 count, and trimethoprim/sulfamethoxazole prophylaxis. Colonization prevalence in asymptomatic adults and in adults with non-PCP respiratory disease was described, and quantitative PCR (qPCR) thresholds to distinguish colonization from microscopy-confirmed PCP reviewed. RESULTS: Thirty-two studies were included, with 27 studies (87%) at high risk of selection bias. P. jirovecii was detected in 19% [95% confidence interval (CI): 12-27%] of 3583 symptomatic and in 9% [95% CI: 0-45%] of 140 asymptomatic adults. Among symptomatic adults, prevalence was 22% [95% CI: 12-35%] by PCR and 15% [95% CI: 9-23%] by microscopy. Seven percent of 435 symptomatic adults had PCR-detected Pneumocystis colonization without evidence of PCP [95% CI: 5-10%, four studies]. One study established a qPCR cutoff of 78 copies/5µl of DNA in 305 induced sputum samples to distinguish Pneumocystis colonization from microscopy-confirmed PCP. CONCLUSION: Despite widened access to HIV services, P. jirovecii remains common in Africa. Prevalence estimates and qPCR-based definitions of colonization are limited, and overall quality of studies is low.

The shift from pulmonary colonization to Pneumocystis pneumonia.

Pulmonary specimen pairs from five patients who presented with pulmonary colonization and later developed Pneumocystis Pneumonia (PcP) were retrospectively examined for P. jirovecii genotyping. A match of genotypes in pulmonary specimen pairs of three patients was observed, whereas a partial match and a mismatch were observed in the fourth and fifth patients, respectively. The genotyping results suggest that the colonization state can differ from PcP but can also represent the incubation period of PcP. Clinicians should not systematically rule out the treatment of putative colonized patients and should at least discuss the initiation of prophylaxis on a case-by-case basis.

The results suggest that clinicians should not systematically rule out the treatment of putative patients colonized by Pneumocystis jirovecii and should at least discuss prophylaxis initiation on a case-by-case basis.

Pneumocystis jirovecii among patients with cystic fibrosis and their household members.

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.

Respiratory microbes detected in hospitalized adults with acute respiratory infections: associations between influenza A(H1N1)pdm09 virus and intensive care unit admission or fatal outcome in Vietnam (2015-2017).

BACKGROUND: Acute respiratory tract infection (ARI) is a leading cause of hospitalization, morbidity, and mortality worldwide. Respiratory microbes that were simultaneously detected in the respiratory tracts of hospitalized adult ARI patients were investigated. Associations between influenza A(H1N1)pdm09 virus (H1N1pdm) detection and intensive care unit (ICU) admission or fatal outcome were determined. METHODS: This prospective observational study was conducted between September 2015 and June 2017 at Bach Mai Hospital, Hanoi, Vietnam. Inclusion criteria were hospitalized patients aged ≥15 years; one or more of symptoms including shortness of breath, sore throat, runny nose, headache, and muscle pain/arthralgia in addition to cough and fever > 37.5 °C; and ≤ 10 days from the onset of symptoms. Twenty-two viruses, 11 bacteria, and one fungus in airway specimens were examined using a commercial multiplex real-time PCR assay. Associations between H1N1pdm detection and ICU admission or fatal outcome were investigated by univariate and multivariate logistic regression analyses. RESULTS: The total of 269 patients (57.6% male; median age, 51 years) included 69 ICU patients. One or more microbes were detected in the airways of 214 patients (79.6%). Single and multiple microbes were detected in 41.3 and 38.3% of patients, respectively. Influenza A(H3N2) virus was the most frequently detected (35 cases; 13.0%), followed by H1N1pdm (29 cases; 10.8%). Hematological disease was associated with ICU admission (p < 0.001) and fatal outcomes (p < 0.001) using the corrected significance level (p = 0.0033). Sex, age, duration from onset to sampling, or number of detected microbes were not significantly associated with ICU admission or fatal outcomes. H1N1pdm detection was associated with ICU admission (odds ratio [OR] 3.911; 95% confidence interval [CI] 1.671-9.154) and fatal outcome (OR 5.496; 95% CI 1.814-16.653) after adjusting for the confounding factors of comorbidities, bacteria/Pneumocystis jirovecii co-detection, and age. CONCLUSIONS: H1N1pdm was associated with severe morbidity and death in adult patients hospitalized with respiratory symptoms. The diagnosis of subtype of influenza virus may be epidemiologically important.

Epidemiological and clinical characteristics of immunocompromised patients infected with Pneumocystis jirovecii in a twelve-year retrospective study from Norway.

BACKGROUND: Pneumocystis pneumonia (PCP) severely menaces modern chemotherapy and immunosuppression. Detailed description of the epidemiology of Pneumocystis jirovecii today is needed to identify candidates for PCP-prophylaxis. METHODS: We performed a 12-year retrospective study of patients with P. jirovecii detected by polymerase chain reaction in Central Norway. In total, 297 patients were included. Comprehensive biological, clinical and epidemiological data were abstracted from patients' medical records. Regional incidence rates and testing trends were also assessed. RESULTS: From 2007 to 2017 we found a 3.3-fold increase in testing for P. jirovecii accompanied by a 1.8-fold increase in positive results. Simultaneously, regional incidence rates doubled from 5.0 cases per 100,000 person years to 10.8. A majority of the study population had predisposing conditions other than human immunodeficiency virus (HIV). Hematological (36.0%) and solid cancers (25.3%) dominated. Preceding corticosteroids were a common denominator for 72.1%. Most patients (74.4%) presented with at least two cardinal symptoms; cough, dyspnea or fever. Main clinical findings were hypoxia, cytopenias and radiological features consistent with PCP. A total of 88 (29.6%) patients required intensive care and 121 (40.7%) suffered at least one complication. In-hospital mortality was 21.5%. Three patients (1.0%) had received prophylaxis. CONCLUSIONS: P. jirovecii is re-emerging; likely due to increasing immunosuppressants use. This opportunistic pathogen threatens the life of heterogenous non-HIV immunosuppressed populations currently at growth. Corticosteroids seem to be a major risk factor. A strategy to increase prophylaxis is called for.

Epidemiology, mortality and effectiveness of prophylaxis for Pneumocystis jiroveci pneumonia among rheumatic patients: a territory-wide study.

BACKGROUND: Pneumocystis jiroveci pneumonia (PJP) is an opportunistic infection affecting immunocompromised individuals. However, evidence regarding the burden and effectiveness of prophylaxis among rheumatic patients remains limited. Delineating the epidemiology and efficacy of prophylaxis among rheumatic patients is urgently needed. METHODS: We performed a territory-wide cohort study of rheumatic patients in Hong Kong. All patients with a diagnosis of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV), immune-mediated myositis (IMM), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), or spondyloarthritis (SpA) between 2015 and 2019 were included. Prevalence, frequency of prophylaxis and mortality of PJP were calculated. Number needed to treat (NNT) analysis was also performed. RESULTS: Out of 21,587 patients (54% RA, 25% SLE, 13% SpA, 5% IMM, 2% AAV and 1% SSc), 1141 (5.3%) patients were prescribed PJP prophylaxis. 48/21,587 (0.2%) developed PJP. No patients who developed PJP received prophylaxis prior to infection. The incidence of PJP was highest among SSc, AAV, and IMM patients. Among these diseases, the majority of PJP occurred while patients were on glucocorticoids at daily prednisolone-equivalent doses of 15 mg/day (P15) or above. PJP prophylaxis was effective with NNT for SSc, AAV and IIM being 36, 48 and 114 respectively. There were 19 PJP-related mortalities and the mortality rate was 39.6%. CONCLUSION: PJP is an uncommon but important infection among rheumatic patients, PJP prophylaxis is effective and should be considered in patients with SSc, AAV and IMM, especially those receiving glucocorticoid doses above P15.

Rapid and precise diagnosis of pneumonia coinfected by Pneumocystis jirovecii and Aspergillus fumigatus assisted by next-generation sequencing in a patient with systemic lupus erythematosus: a case report.

BACKGROUND: Pneumocystis jirovecii and Aspergillus fumigatus, are opportunistic pathogenic fungus that has a major impact on mortality in patients with systemic lupus erythematosus. With the potential to invade multiple organs, early and accurate diagnosis is essential to the survival of SLE patients, establishing an early diagnosis of the infection, especially coinfection by Pneumocystis jirovecii and Aspergillus fumigatus, still remains a great challenge. CASE PRESENTATION: In this case, we reported that the application of next -generation sequencing in diagnosing Pneumocystis jirovecii and Aspergillus fumigatus coinfection in a Chinese girl with systemic lupus erythematosus (SLE). Voriconazole was used to treat pulmonary aspergillosis, besides sulfamethoxazole and trimethoprim (SMZ-TMP), and caspofungin acetate to treat Pneumocystis jirovecii infection for 6 days. On Day 10 of admission, her chest radiograph displayed obvious absorption of bilateral lung inflammation though the circumstance of repeated fever had not improved. Unfortunately, the patient discharged from the hospital since the financial burden, and during the follow-up, it was documented the patient died within one week after discharge. CONCLUSIONS: This successful application of the next generation sequencing assisting the rapid diagnosis of Pneumocystis jirovecii and Aspergillus fumigatus coinfection provides a new perspective in the clinical approach against the systematic fungi infections and highlights the potential of this technique in rapid etiological diagnosis.

Healthcare-associated Pneumocystis jirovecii Pneumonia (PJP) Infection in HIV-negative Adults: a Multicenter Study.

BACKGROUND: Pneumocystis jirovecii pneumonia (PJP) is an opportunistic infection in immunocompromised patients. Clusters of PJP, especially among organ transplant recipients in clinic settings were described. Data regarding nosocomial PJP infection among inpatients are limited. OBJECTIVES: To assess the magnitude and characteristics of inpatient healthcare-associated PJP infection (HCA-PJP) in HIV-negative patients. METHODS: A retrospective chart review of hospitalized PJP patients was performed to identify HCA-PJP. The study was performed at six medical centers in Israel from 2006 to 2016. HCA-PJP was defined as cases of hospital-onset or those with documented contact with a PJP patient. We reviewed and cross-matched temporal and spatial co-locations of patients. Clinical laboratory characteristics and outcomes were compared. RESULTS: Seventy-six cases of PJP were identified. Median age was 63.7 years; 64% men; 44% hematological malignancies; 18% inflammatory diseases; and 61% steroid usage. Thirty-two patients (42%) were defined as HCA-PJP: 18/32 (23.6%) were hospitalized at onset and 14/32 (18.4%) had a previous encounter with a PJP patient. Time from onset of symptoms to diagnosis was shorter in HCA-PJP vs. community-PJP (3.25 vs. 11.23 days, P = 0.009). In multivariate analysis, dyspnea at presentation (odds ratio [OR] 16.79, 95% confidence interval [95%CI] 1.78-157.95) and a tendency toward higher rate of ventilator support (72% vs. 52%, P = 0.07, OR 5.18, 95%CI 0.7-30.3) were independently associated with HCA-PJP, implying abrupt disease progression in HCA-PJP. CONCLUSIONS: HCA-PJP was common. A high level of suspicion for PJP among selected patients with nosocomial respiratory infection is warranted. Isolation of PJP patients should be considered.

High incidence of Pneumocystis jirovecii pneumonia in allogeneic hematopoietic cell transplant recipients in the modern era.

BACKGROUND: International guidelines for Pneumocystis jirovecii pneumonia (PJP) prevention recommend prophylaxis for ≥6 months following allogeneic hematopoietic cell transplantation, and longer in patients with graft-versus-host disease (GVHD) or on immunosuppressive therapy (IST). These recommendations are based on cohorts of patients who did not routinely receive anti-thymocyte globulin (ATG) for GVHD prophylaxis. METHODS: We performed a retrospective chart review of 649 patients, all of whom received ATG as part of GVHD prophylaxis. RESULTS: The cumulative incidence of definite PJP was 3.52% at both 3 and 5 years (median follow up, 1648 days for survivors). PJP occurred in 13 non-GVHD patients between days 207 and 508, due in part to low CD4 T-cell counts (<200 CD4 T cells/µL). PJP occurred in eight GVHD patients between days 389 and 792, due in part to non-adherence to PJP prophylaxis guidelines (discontinuation of PJP prophylaxis at <3 months after discontinuation of IST). Breakthrough PJP infection was not observed in patients receiving prophylaxis with cotrimoxazole, dapsone or atovaquone, whereas three cases were observed with inhaled pentamidine. DISCUSSION: In conclusion, for non-GVHD patients receiving ATG-containing GVHD prophylaxis, 6 months of PJP prophylaxis is inadequate, particularly if the CD4 T-cell count is <200 cells/µL or if there is a high incidence of PJP in the community. For patients with GVHD receiving ATG-containing GVHD prophylaxis, continuing PJP prophylaxis until ≥3 months post-discontinuation of IST is important. Cotrimoxazole, dapsone and atovaquone are preferred over inhaled pentamidine.

Genotyping of Pneumocystis jirovecii isolates obtained from clinical samples by multilocus sequencing: a molecular epidemiology study conducted in Turkey.

Pneumocystis jirovecii is an opportunistic respiratory pathogen causing Pneumocystis pneumonia (PcP) in immunocompromised patients. The aim of this study was to investigate the genetic diversity of P. jirovecii isolates (n: 84) obtained from PcP patients using multilocus sequencing method based on mt26S, SOD, and CYB loci. Among the 84 clinical samples that were positive for P. jirovecii DNA, 31 (36.90%) of them were genotyped using at least one locus. Of the 31 clinical samples, 26 of them were successfully genotyped using all loci whereas three samples were genotyped using either mt26S/CYB loci or mt26S/SOD loci. Additionally, there were two more clinical samples that were genotyped using CYB or SOD locus. Using mt26S locus, genotypes 2, 3, 7, and 8 were detected. Frequencies of genotype 7 and 8 were higher and both of them were found in 11 (n: 29; 37.93%) clinical samples. Using SOD locus, SOD 1, 2, and 4 genotypes were detected. SOD 1 was the predominant genotype (20/28; 71.42%). During the analyses of CYB locus, CYB 1, 2, 5, 6, and 7 as well as a new CYB genotype were detected. CYB 1 (16/29; 55.17%) and 2 (10/29; 34.48%) were the predominant genotypes. Overall, according to the multilocus sequencing results E, F, M, N, P, and V multilocus genotypes were detected among the PcP patients. In addition, SOD 1 was the predominant genotype and CYB had a more polymorphic locus.

Pneumocystis jirovecii pneumonia in patients treated for systemic autoimmune disorders: a retrospective analysis of patient characteristics and outcome.

Objectives: Pneumocystis jirovecii is an opportunistic fungus. Pneumocystis jirovecii pneumonia (PJP) is well known in the human immunodeficiency virus (HIV)-infected population, but in non-HIV-related immunosuppressed patients, risk factors are largely unknown. We studied the characteristics and outcome of patients treated for systemic autoimmune disorders infected with P. jirovecii, aiming to clarify risk stratification to guide prophylaxis. Method: Clinical charts collected between 2010 and 2016 at the University Hospital of Leuven (Belgium) were reviewed. Information on type of systemic disorder, organ involvement, immunosuppressant use, and comorbidity was collected, and laboratory results were consulted. Results: In total, 39 cases of non-HIV PJP were retrieved, 24 of whom had pre-existing pulmonary disease. All were on immunosuppressant medication at the time of infection, the majority (36/39) taking glucocorticoids, with a median dose of 16 mg methylprednisolone over the past 3 months. Of the 39 cases, 21 were admitted to the intensive care unit and mortality reached 35%. Age and pulmonary disease correlated positively and methotrexate use negatively with mortality. When applying current prophylactic strategies to our cohort, 50% of infections could theoretically have been prevented. Conclusion: PJP is a rare but relevant clinical problem when caring for immunosuppressed patients with autoimmune systemic disorders. Pulmonary disease and age are risk factors for acquiring the infection and carry a worse prognosis. More studies are needed to further define prophylactic criteria.

Pneumocystis jirovecii and microsporidia: An unusual coinfection in HIV patients?

Pneumocystis jirovecii and microsporidia species are recognized as opportunistic infectious pathogens in AIDS patients. Coinfection of both in one patient has been rarely reported. The aim of the present study was to investigate the coinfection of P. jirovecii and microsporidia in different tissues from AIDS deceased patients. Post mortem histological finding of P. jirovecii and microsporidia was demonstrated by means of the Grocott's methenamine silver and Brown Brenn staining, respectively. Molecular technique was used for identification and characterization of both fungi. Out of the 514 autopsied cases P. jirovecii and microsporidia species were identified in 53 (10.3%) and 62 (12.1%) cases respectively. A total of five cases (0.97%) coinfected with Pneumocystis and microsporidia were recovered from all analyzed autopsies. Coinfection of Pneumocystis and microsporidia is very challenging and raises interesting issues about host-parasite relationship. The early diagnosis of both pathogens must be crucial to establish correct and early treatments, improve the patient's evolution, reducing the risk of death.