Outcome and prognostic factors of Pneumocystis jirovecii pneumonia in immunocompromised adults: a prospective observational study

Metagenomic Next-Generation Sequencing for Accurate Diagnosis of Pneumocystis jirovecii Pneumonia: A Comparative Study with Traditional Methods

Background

Metagenomic next-generation sequencing (mNGS) is a high-throughput sequencing technique that identifies a wide array of pathogens directly from clinical specimens. This study evaluates the diagnostic value of mNGS in Pneumocystis jirovecii pneumonia (PJP) and compares its efficacy with traditional detection methods, including Grocott's Methenamine Silver (GMS) staining, serum (1-3)-β-D-Glucan (BDG) testing, and Lactate Dehydrogenase (LDH) testing.

Methods

Seventy-eight patients hospitalized between January 2022 and March 2023 with suspected pulmonary infections were included. Patients were eligible for mNGS if they exhibited symptoms such as fever, cough, dyspnea, or progressive hypoxemia, and met specific clinical criteria for PJP. Specimens obtained included bronchoalveolar lavage fluid, sputum, and peripheral blood. Positive rates and pathogen distributions detected by mNGS and traditional methods were compared.

Results

In the PJP group, 25%, 37.5%, and 9.38% of patients had solid organ tumors, corticosteroid use, and skin diseases, respectively, significantly higher than in the non-PJP group. The sensitivity and specificity of mNGS were both 100%, significantly higher than those of serum BDG (sensitivity 50%, specificity 81.8%) and LDH (sensitivity 9.3%, specificity 91.3%). Significant differences in microbial composition between the PJP and Non-PJP groups were observed. mNGS detected multiple mixed pathogens in 96.88% of PJP cases, with 68.75% exhibiting mixed bacterial and viral infections. Notably, 71% of patients improved following antibacterial treatment based on mNGS results.

Conclusion

mNGS technology shows superior sensitivity and specificity in diagnosing PJP and guides precise treatment for complex pulmonary infections.

Clinical course and prognostic factors of Pneumocystis pneumonia with respiratory failure in non-HIV patients

Background

Compared with Human Immunodeficiency Virus (HIV) patients, non-HIV patients with Pneumocystis pneumonia (PCP) have more rapid onset, more rapid progression, and higher mortality.

Objectives

To investigate the predictive value of variables obtained upon hospital admission for in-hospital death and 90-day outcomes in non-HIV-PCP patients with respiratory failure (RF).

Methods

This was a single center retrospective study in a tertiary care institution over 15 years. It included all adults inpatients (≥18 years old) with laboratory confirmed non-HIV-PCP with RF who were discharged or died from Peking University First Hospital between April 1st, 2007 and November 1st, 2022. Epidemiological, clinical, laboratory, imaging and outcome data were collected from patient records.

Results

In this study, a total of 146 non-HIV-PCP patients with RF were included. There were 57 patients (39%) died during hospitalization, 44 patients (53%) died in Intensive care unit (ICU). A total of 137 patients completed 90 days of follow-up, of which 58 (42.3%) died. The multivariable regression analysis revealed that a CD8+ T cell count <115/μl (P=0.009), bronchoalveolar lavage fluid (BALF)-neutrophil percentage ≥50% (P=0.047), the time from corticosteroids withdrawal to symptom onset ≤5 days (P=0.012), and the time from visit to initiation of sulfonamides ≥2 days (P=0.011) were independent risk factors for in-hospital death. Furthermore, a CD8+ T cell count < 115/μl (P=0.001) and the time from visit to initiation of sulfonamides therapy ≥2 days (P=0.033) was independently associated with 90-day all-cause death.

Conclusions

A low CD8+ T cell count in peripheral blood, a high percentage of BALF-neutrophils, a short time from corticosteroids withdrawal to symptom onset, and a long time from visit to initiation of sulfonamides are associated with poor prognosis in non-HIV-PCP patients with RF.

Features and global impact of invasive fungal infections caused by Pneumocystis jirovecii: A systematic review to inform the World Health Organization fungal priority pathogens list

This systematic review evaluates the current global impact of invasive infections caused by Pneumocystis jirovecii (principally pneumonia: PJP), and was carried out to inform the World Health Organization Fungal Priority Pathogens List. PubMed and Web of Science were used to find studies reporting mortality, inpatient care, complications/sequelae, antifungal susceptibility/resistance, preventability, annual incidence, global distribution, and emergence in the past 10 years, published from January 2011 to February 2021. Reported mortality is highly variable, depending on the patient population: In studies of persons with HIV, mortality was reported at 5%-30%, while in studies of persons without HIV, mortality ranged from 4% to 76%. Risk factors for disease principally include immunosuppression from HIV, but other types of immunosuppression are increasingly recognised, including solid organ and haematopoietic stem cell transplantation, autoimmune and inflammatory disease, and chemotherapy for cancer. Although prophylaxis is available and generally effective, burdensome side effects may lead to discontinuation. After a period of decline associated with improvement in access to HIV treatment, new risk groups of immunosuppressed patients with PJP are increasingly identified, including solid organ transplant patients.

Characteristics and Prognosis Factors of Pneumocystis jirovecii Pneumonia According to Underlying Disease: A Retrospective Multicenter 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.

Critical illness due to infection in people living with HIV

People living with HIV comprise a substantial number of the patients admitted to intensive care. This number varies according to geography, but all areas of the world are affected. In lower-income and middle-income countries, the majority of intensive care unit (ICU) admissions relate to infections, whereas in high-income countries, they often involve HIV-associated non-communicable diseases diagnoses. Management of infections potentially resulting in admission to the ICU in people living with HIV include sepsis, respiratory infections, COVID-19, cytomegalovirus infection, and CNS infections, both opportunistic and non-opportunistic. It is crucial to know which antiretroviral therapy (ART) is appropriate, when is the correct time to administer it, and to be aware of any safety concerns and potential drug interactions with ART. Although ART is necessary for controlling HIV infections, it can also cause difficulties relevant to the ICU such as immune reconstitution inflammatory syndrome, and issues associated with ART administration in patients with gastrointestinal dysfunction on mechanical ventilation. Managing infection in people with HIV in the ICU is complex, requiring collaboration from a multidisciplinary team knowledgeable in both the management of the specific infection and the use of ART. This team should include intensivists, infectious disease specialists, pharmacists, and microbiologists to ensure optimal outcomes for patients.

Pneumocystis jirovecii Pneumonia in HIV-Negative, Non-transplant Patients: Epidemiology, Clinical Manifestations, Diagnosis, Treatment, and Prevention

Purpose of Review

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic fungal infection that is increasingly seen in HIV-negative patients with immune compromise due to other etiologies. We lack comprehensive clinical recommendations for this population.

Recent Findings

In non-HIV cases, PJP has a mortality rate of up to 50%, which is unacceptable despite the presence of safe and effective prophylaxis and therapy. Steroid use is one of the most common risk factors for disease development. New data suggests that lower doses of the preferred treatment regimen, TMP-SMX, may be equally effective for treatment while limiting side effects. While commonly used, the benefit of corticosteroids for the treatment of PJP has recently been called into question, with a recent multicenter cohort demonstrating no benefit among solid organ transplant recipients.

Summary

A high suspicion of PJP in individuals with pneumonia during immunosuppressant use is crucial. Therapeutic options are evolving to decrease potential side effects while maintaining efficacy in this highly morbid disease.

Clinical Characteristics and Prognostic Predictors of Pneumocystis Jirovecii Pneumonia in Patients with and without Chronic Pulmonary Disease: A Retrospective Cohort Study

Objective

Pneumocystis jirovecii pneumonia (PJP) is a severe respiratory infection caused by Pneumocystis jirovecii in immunocompromised hosts. The role of P. jirovecii colonization in the development or progression of various pulmonary diseases has been reported. Our aim was to explore serial change in serum biomarkers and the independent risk factors for mortality in patients with and without chronic pulmonary diseases who developed PJP.

Methods

We performed a retrospective study to select patients with Pneumocystis jirovecii pneumonia between January 1, 2012, and December 31, 2021. Information regarding demographics, clinical characteristics, underlying diseases, laboratory tests, treatment, and outcomes was collected. Univariate and multivariate logistic regression analyses were used to identify independent predictors of in-hospital mortality.

Results

A total of 167 patients diagnosed with PJP were included in the study: 53 in the CPD-PJP group and 114 in the NCPD-PJP group. The number of patients with PJP showed an increasing trend over the 10-year period. A similar trend was observed for in-hospital mortality. Independent risk factors associated with death in the NCPD-PJP group were procalcitonin level (adjusted OR 1.08, 95% CI 1.01-1.16, P=0.01), pneumothorax (adjusted OR 0.07, 95% CI 0.01-0.38, P=0.002), neutrophil count (adjusted OR 1.27, 95% CI 1.05-1.53, P=0.01) at 14 days, and hemoglobin level (adjusted OR 0.94, 95% CI 0.91-0.98; P=0.002) at 14 days after admission. The risk factor associated with death in the CPD-PJP group was neutrophil count (adjusted OR 1.19, 95% CI 0.99-1.43; P=0.05) at 14 days after admission.

Conclusion

The risk factors for death were different between patients with PJP with and without chronic pulmonary disease. Early identification of these factors in patients with PJP and other underlying diseases may improve prognosis.

Pneumocystis jirovecii pneumonia mortality risk associated with preceding long-term steroid use for the underlying disease: A multicenter, retrospective cohort study

OBJECTIVE

Long-term steroid use increases the risk of developing Pneumocystis pneumonia (PcP), but there are limited reports on the relation of long-term steroid and PcP mortality.

METHODS

Retrospective multicenter study to identify risk factors for PcP mortality, including average steroid dose before the first visit for PcP in non-human immunodeficiency virus (HIV)-PcP patients. We generated receiver operating characteristic (ROC) curves for 90-day all-cause mortality and the mean daily steroid dose per unit body weight in the preceding 10 to 90 days in 10-day increments. Patients were dichotomized by 90-day mortality and propensity score-based stabilized inverse probability of treatment weighting (IPTW) adjusted covariates of age, sex, and underlying disease. Multivariate analysis with logistic regression assessed whether long-term corticosteroid use affected outcome.

RESULTS

Of 133 patients with non-HIV-PcP, 37 died within 90 days of initial diagnosis. The area under the ROC curve for 1-40 days was highest, and the optimal cutoff point of median adjunctive corticosteroid dosage was 0.34 mg/kg/day. Past steroid dose, underlying interstitial lung disease and emphysema, lower serum albumin and lower lymphocyte count, higher lactate dehydrogenase, use of therapeutic pentamidine and therapeutic high-dose steroids were all significantly associated with mortality. Underlying autoimmune disease, past immunosuppressant use, and a longer time from onset to start of treatment, were associated lower mortality. Logistic regression analysis after adjusting for age, sex, and underlying disease with IPTW revealed that steroid dose 1-40 days before the first visit for PcP (per 0.1 mg/kg/day increment, odds ratio 1.36 [95% confidence interval = 1.16-1.66], P<0.001), low lymphocyte counts, and high lactate dehydrogenase revel were independent mortality risk factor, while respiratory failure, early steroid, and sulfamethoxazole/trimethoprim for PcP treatment did not.

CONCLUSION

A steroid dose before PcP onset was strongly associated with 90-day mortality in non-HIV-PcP patients, emphasizing the importance of appropriate prophylaxis especially in this population.

A regimen based on the combination of trimethoprim/sulfamethoxazole with caspofungin and corticosteroids as a first-line therapy for patients with severe non-HIV-related pneumocystis jirovecii pneumonia: a retrospective study in a tertiary hospital

BACKGROUND

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening and severe disease in immunocompromised hosts. A synergistic regimen based on the combination of sulfamethoxazole-trimethoprim (SMX-TMP) with caspofungin and glucocorticosteroids (GCSs) may be a potential first-line therapy for PJP. Therefore, it is important to explore the efficacy and safety of this synergistic therapy for treating non-HIV-related PJP patients.

METHODS

We retrospectively analysed the data of 38 patients with non-HIV-related PJP at the First Affiliated Hospital of Xi'an Jiaotong University. Patients were divided into two groups: the synergistic therapy group (ST group, n = 20) and the monotherapy group (MT group, n = 18). All patients were from the ICU and were diagnosed with severe PJP. In the ST group, all patients were treated with SMX-TMP (TMP 15-20 mg/kg per day) combined with caspofungin (70 mg as the loading dose and 50 mg/day as the maintenance dose) and a GCS (methylprednisolone 40-80 mg/day). Patients in the MT group were treated only with SMX-TMP (TMP 15-20 mg/kg per day). The clinical response, adverse events and mortality were compared between the two groups.

RESULTS

The percentage of patients with a positive clinical response in the ST group was significantly greater than that in the MT group (100.00% vs. 66.70%, P = 0.005). The incidence of adverse events in the MT group was greater than that in the ST group (50.00% vs. 15.00%, P = 0.022). Furthermore, the dose of TMP and duration of fever in the ST group were markedly lower than those in the MT group (15.71 mg/kg/day vs. 18.35 mg/kg/day (P = 0.001) and 7.00 days vs. 11.50 days (P = 0.029), respectively). However, there were no significant differences in all-cause mortality or duration of hospital stay between the MT group and the ST group.

CONCLUSIONS

Compared with SMZ/TMP monotherapy, synergistic therapy (SMZ-TMP combined with caspofungin and a GCS) for the treatment of non-HIV-related PJP can increase the clinical response rate, decrease the incidence of adverse events and shorten the duration of fever. These results indicate that synergistic therapy is effective and safe for treating severe non-HIV-related PJP.

Clinical significance of mutations in dihydropteroate synthase in Pneumocystis jirovecii pneumonia among non-HIV-infected patients

BACKGROUND

Dihydropteroate synthase (DHPS) mutations may be associated with trimethoprim-sulfamethoxazole resistance in Pneumocystis jirovecii pneumonia (PCP) and worse clinical outcomes. However, the clinical significance of DHPS mutations in PCP among non-human immunodeficiency virus (HIV)-infected patients remains unclear.

METHODS

Patients with PCP in three tertiary referral hospitals in Taiwan between 2016 and 2020 were retrospectively enrolled. Two point mutations, Thr55Ala and Pro57Ser, in the DHPS protein were analysed. Patients with invalid DHPS mutations in the respiratory specimen, chronic respiratory failure, receiving endotracheal intubation for surgical intervention, HIV infection, Pneumocystis jirovecii colonisation, and no lactate dehydrogenase (LDH) data were excluded. The primary outcome was 30-day survival.

RESULTS

A total of 215 patients were analysed. Mutants inside DHPS were found in 78 patients (36.3%) and 68 patients (31.6%) died within 30 days. A total of 214 patients (99.5%) received trimethoprim-sulfamethoxazole as the first-line treatment. The rates of mechanical ventilation, 30-day, and in-hospital mortality were similar between wild-type and mutant DHPS PCP. After adjusting for important confounders, LDH > 500 µ/L (adjusted hazard ratio [aHR] = 2.448, P = 0.001), pneumonia severity index > 135 mg/dL (aHR = 1.689, P = 0.049), and having solid tumours (aHR = 1.832, P = 0.034) were independently associated with higher mortality. In subgroup analysis, mutant DHPS PCP patients had less 30-day mortality among patients aged > 65 years (P = 0.049), with lymphopenia (P = 0.040), and those without solid tumour (P = 0.045).

CONCLUSIONS

In non-HIV-infected PCP, point mutants inside DHPS may not be associated with trimethoprim-sulfamethoxazole treatment outcomes. Further prospective large-scale studies are warranted.

Machine Learning Models for Prediction of Severe Pneumocystis carinii Pneumonia after Kidney Transplantation: A Single-Center Retrospective Study

BACKGROUND

The objective of this study was to formulate and validate a prognostic model for postoperative severe Pneumocystis carinii pneumonia (SPCP) in kidney transplant recipients utilizing machine learning algorithms, and to compare the performance of various models.

METHODS

Clinical manifestations and laboratory test results upon admission were gathered as variables for 88 patients who experienced PCP following kidney transplantation. The most discriminative variables were identified, and subsequently, Support Vector Machine (SVM), Logistic Regression (LR), Random Forest (RF), K-Nearest Neighbor (KNN), Light Gradient Boosting Machine (LGBM), and eXtreme Gradient Boosting (XGB) models were constructed. Finally, the models' predictive capabilities were assessed through ROC curves, sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), and F1-scores. The Shapley additive explanations (SHAP) algorithm was employed to elucidate the contributions of the most effective model's variables.

RESULTS

Through lasso regression, five features-hemoglobin (Hb), Procalcitonin (PCT), C-reactive protein (CRP), progressive dyspnea, and Albumin (ALB)-were identified, and six machine learning models were developed using these variables after evaluating their correlation and multicollinearity. In the validation cohort, the RF model demonstrated the highest AUC (0.920 (0.810-1.000), F1-Score (0.8), accuracy (0.885), sensitivity (0.818), PPV (0.667), and NPV (0.913) among the six models, while the XGB and KNN models exhibited the highest specificity (0.909) among the six models. Notably, CRP exerted a significant influence on the models, as revealed by SHAP and feature importance rankings.

CONCLUSIONS

Machine learning algorithms offer a viable approach for constructing prognostic models to predict the development of severe disease following PCP in kidney transplant recipients, with potential practical applications.

Trends in the Epidemiology of Pneumocystis Pneumonia in Immunocompromised Patients without HIV Infection

The increasing morbidity and mortality of life-threatening Pneumocystis pneumonia (PCP) in immunocompromised people poses a global concern, prompting the World Health Organization to list it as one of the 19 priority invasive fungal diseases, calling for increased research and public health action. In response to this initiative, we provide this review on the epidemiology of PCP in non-HIV patients with various immunodeficient conditions, including the use of immunosuppressive agents, cancer therapies, solid organ and stem cell transplantation, autoimmune and inflammatory diseases, inherited or primary immunodeficiencies, and COVID-19. Special attention is given to the molecular epidemiology of PCP outbreaks in solid organ transplant recipients; the risk of PCP associated with the increasing use of immunodepleting monoclonal antibodies and a wide range of genetic defects causing primary immunodeficiency; the trend of concurrent infection of PCP in COVID-19; the prevalence of colonization; and the rising evidence supporting de novo infection rather than reactivation of latent infection in the pathogenesis of PCP. Additionally, we provide a concise discussion of the varying effects of different immunodeficient conditions on distinct components of the immune system. The objective of this review is to increase awareness and knowledge of PCP in non-HIV patients, thereby improving the early identification and treatment of patients susceptible to PCP.

Cotrimoxazole as a Preventative Intervention for Pneumocystis Pneumonia in Pemphigus Patients Treated with Rituximab: A Retrospective Study

INTRODUCTION

Pneumocystis jirovecii pneumonia (PJP) is a severe, life-threatening complication in patients treated with rituximab. However, there is no consensus on the primary prophylaxis for it in rituximab-treated pemphigus patients. Therefore, we sought to investigate the prophylactic efficacy and safety profile of cotrimoxazole for reducing the risk of developing PJP in pemphigus patients receiving rituximab.

METHODS

This single-center retrospective study investigated 148 pemphigus patients undergoing a first cycle of rituximab between 2008 and 2021 at a tertiary referral center in northern Taiwan. Patients were divided into the prophylaxis group (N = 113) and the control group (N = 35) according to whether or not cotrimoxazole was administered. The primary outcome was the 1-year incidence of PJP in the two groups, while the secondary outcome was the incidence of cotrimoxazole-related adverse events.

RESULTS

Of the 148 patients enrolled in this study, three patients, all in the control group, developed PJP during the 1-year follow-up. The incidence of PJP (8.6%) in the control group was significantly higher than that in the prophylaxis group (0%) (p = 0.012). The incidence of cotrimoxazole-related adverse events was 2.7%, and none of the cases were associated with life-threatening conditions. In addition, the cumulative prednisolone dose was associated with a trend of a higher risk of PJP (p = 0.0483).

CONCLUSIONS

Prophylactic cotrimoxazole significantly reduces the risk of PJP in a certain high-risk population and has a tolerable safety profile.

Pneumocystis jirovecii Pneumonia Diagnostic Approach: Real-Life Experience in a Tertiary Centre

Pneumocystis jirovecii pneumonia (PJP) in immunocompromised patients entails high mortality and requires adequate laboratory diagnosis. We compared the performance of a real time-PCR assay against the immunofluorescence assay (IFA) in the routine of a large microbiology laboratory. Different respiratory samples from HIV and non-HIV-infected patients were included. The retrospective analysis used data from September 2015 to April 2018, which included all samples for which a P. jirovecii test was requested. A total of 299 respiratory samples were tested (bronchoalveolar lavage fluid (n = 181), tracheal aspirate (n = 53) and sputum (n = 65)). Forty-eight (16.1%) patients fulfilled the criteria for PJP. Five positive samples (10%) had only colonization. The PCR test was found to have a sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 96%, 98%, 90% and 99%, compared to 27%, 100%, 100% and 87%, for the IFA, respectively. PJ-PCR sensitivity and specificity were >80% and >90% for all tested respiratory samples. Median cycle threshold values in definite PJP cases were 30 versus 37 in colonized cases (p < 0.05). Thus, the PCR assay is a robust and reliable test for the diagnosis PJP in all respiratory sample types. Ct values of ≥36 could help to exclude PJP diagnosis.

Pneumocystis jiroveci Pneumonia: A Review of Management in Human Immunodeficiency Virus (HIV) and Non-HIV Immunocompromised Patients

Pneumocystis jirovecii pneumonia is an opportunistic fungal infection that was mainly associated with pneumonia in patients with advanced human immunodeficiency virus (HIV) disease. There has been a decline in Pneumocystis jirovecii pneumonia incidence in HIV since the introduction of antiretroviral medications. However, its incidence is increasing in non-HIV immunocompromised patients including those with solid organ transplantation, hematopoietic stem cell transplantation, solid organ tumors, autoimmune deficiencies, and primary immunodeficiency disorders. We aim to review and summarize the etiology, epidemiology, clinical presentation, diagnosis, and management of Pneumocystis jirovecii pneumonia in HIV, and non-HIV patients. HIV patients usually have mild-to-severe symptoms, while non-HIV patients present with a rapidly progressing disease. Induced sputum or bronchoalveolar lavage fluid can be used to make a definitive diagnosis of Pneumocystis jirovecii pneumonia. Trimethoprim-sulfamethoxazole is considered to be the first-line drug for treatment and has proven to be highly effective for Pneumocystis jirovecii pneumonia prophylaxis in both HIV and non-HIV patients. Pentamidine, atovaquone, clindamycin, and primaquine are used as second-line agents. While several diagnostic tests, treatments, and prophylactic regimes are available at our disposal, there is need for more research to prevent and manage this disease more effectively.

Clinical characteristics and risk factor analysis of Pneumocystis jirovecii pneumonia in patients with CKD: a machine learning-based approach

Patients with chronic kidney disease (CKD) who are being treated with immunosuppressive medications are at risk for developing Pneumocystis jirovecii pneumonia (PCP). We attempted to characterize the clinical aspects of PCP in CKD patients in order to alert high-risk patients with bad prognosis. A retrospective study of CKD patients was conducted from June 2018 to June 2022. Based on PCP diagnostic criteria, these patients were divided into PCP and non-PCP groups. Using univariate and multivariate logistic regression analysis, risk indicators were evaluated, and nomogram and decision tree were developed. Of the CKD patients screened for Pneumocystis carinii nucleic acid, 1512 were included. Two-hundred forty four (16.14%) were diagnosed with PCP. Of the PCP, 88.5% was receiving glucocorticoid (GC) therapy, of which 66.3% received more than 0.5 mg/kg GC. Multivariate analysis showed that membranous nephropathy (OR 2.35, 95% CI 1.45-3.80), immunosuppressive therapy (OR 1.94, 95% CI 1.06-3.69), and ground glass opacity of CT scanning (OR 1.71, 95% CI 1.10-2.65) were associated with increased risk of Pneumocystis carinii infection. The AUC of nomogram based on logistics regression was 0.78 (0.75-0.81). The mortality in patients with PCP was 32.40%. Univariate analysis and decision tree showed that pulmonary insufficiency (PO₂: OR 0.98, 95% CI 0.96-1.00), elevated APTT (OR 1.07, 95% CI 1.04-1.11), and reduced hemoglobin (OR 0.97, 95% CI 0.96-0.98) were associated with poor prognosis. PCP is not rare in CKD patients, particularly in those treated with immunosuppressive therapy. Considering the high mortality of the cases, further studies on the prevention and management of these patients are needed.

Risk factors for Pneumocystis pneumonia with acute respiratory failure among kidney transplant recipients

PURPOSE

One of the rare life-threatening fungal infections is pneumocystis pneumonia (PCP). Immunocompromised patients are the main vulnerable population. We investigate the risk factors associated with the development of severe PCP infection with acute respiratory failure after kidney transplantation.

MATERIALS AND METHODS

This is a retrospective, single-center, case-control study. PCP patients who are kidney transplant recipients and required high-flow oxygen support or mechanical ventilation between March 2009 and February 2017 were included in the study. The comparison was conducted between the non-severe and severe PCP groups. To identify associated risk factors, we performed univariate and multivariate logistic regression.

RESULTS

Among the total 2,330 kidney transplant recipients, 50 patients (2.1%) were diagnosed with PCP. Of these, 27 patients (54.0%) had severe PCP and 7 patients (14.0%) died, all of them were severe PCP patients. In the severe PCP group, the time from transplantation to PCP diagnosis (23.4 ± 24.9 months vs. 13.7 ± 9.9 months, p = 0.090) was insignificantly faster than in the non-severe PCP group. According to multiple logistic regression analysis, the significant risk factors associated with severe PCP were as follows, age (odds ratios (OR) 1.07; 95% confidence intervals (CI): 1.01-1.13; p = 0.027), time from transplantation to PCP diagnosis (odds ratios (OR) 0.92; 95% confidence intervals (CI): 0.86-0.99; p = 0.024), lymphopenia (OR 6.48; 95% CI: 1.05-40.09; p = 0.044), and history of acute rejection within 1 year (OR 8.28; 95% CI: 1.29-53.20; p = 0.026).

CONCLUSION

Patients who have lymphopenia at the time of hospital admission or have been recently treated with acute rejection are more likely to progress to severe PCP, requiring intensive monitoring and aggressive treatment.

The Role of Macrophages and Alveolar Epithelial Cells in the Development of ARDS

Acute lung injury (ALI) usually causes acute respiratory distress syndrome (ARDS), or even death in critical ill patients. Immune cell infiltration in inflamed lungs is an important hallmark of ARDS. Macrophages are a type of immune cell that participate in the entire pathogenic trajectory of ARDS and most prominently via their interactions with lung alveolar epithelial cells (AECs). In the early stage of ARDS, classically activated macrophages secrete pro-inflammatory cytokines to clearance of the pathogens which may damage alveolar AECs cell structure and result in cell death. Paradoxically, in late stage of ARDS, anti-inflammatory cytokines secreted by alternatively activated macrophages dampen the inflammation response and promote epithelial regeneration and alveolar structure remodeling. In this review, we discuss the important role of macrophages and AECs in the progression of ARDS.

Previous corticosteroid exposure associates with an increased Pneumocystis jirovecii pneumonia mortality among HIV-negative patients: a global research network with a follow-up multicenter case-control study

Background

HIV-negative patients have substantial mortality from Pneumocystis jirovecii pneumonia (PJP). We lack predictors of HIV-negative PJP-associated mortality.

Objective

We aim to characterize the role of prior corticosteroid exposure in PJP-related mortality.

Methods

We queried a global research network to identify adult HIV-negative patients with PJP with or without corticosteroid exposure in the preceding year before diagnosis (n = 8,021). We performed a propensity score-matched analysis to adjust baseline patient characteristics and analyzed outcomes. We follow-up the results with a multicenter ten years retrospective case-control cohort of HIV-negative patients tested for PJP by PCP Direct Fluorescent Antigen. We used a Cox proportional hazards model for survival analysis.

Results

1822 HIV-negative propensity-scored matched patients with prior corticosteroid exposure had significantly increased 10 weeks (16% versus 9%, p < 0.0001) and one-year mortality after PJP diagnosis (23% versus 14%, p < 0.0001). (1→3)-β-D-glucan (197.6 ± 155.8 versus 63 ± 0 pg/ml, p = 0.014), ferritin levels (1227 ± 2486 versus 768 ± 1060 mcg/l, p = 0.047), lymphopenia (1.5 ± 1.5 versus 2.0 ± 1.6 10³ cells/µl, p < 0.0001) and hypoxia (SatO₂: 86.7% versus 91.6%, p < 0.0001) were higher or worse in those with prior steroid use. Patients who died were more likely to have previously received dexamethasone (35% versus 16%, p < 0.001) or prednisone (49% versus 29%, p < 0.001). Adjusted Cox proportional-hazard model validation showed an independently increased mortality at 10 weeks (HR: 3.7, CI: 1.5-9.2, p = 0.004) and 1 year (HR: 4.5, CI: 2.0-10.4, p < 0.0001) among HIV-negative patients with previous corticosteroid exposure.

Conclusion

Preceding corticosteroids in HIV-negative patients with PJP are associated with higher mortality. A higher fungal burden may influence corticosteroid-mediated mortality. Assessment of PJP prophylaxis must become a standard clinical best practice when instituting corticosteroid therapy courses.

The diagnostic value of metagenomic next-generation sequencing for identifying Pneumocystis jirovecii infection in non-HIV immunocompromised patients

Background

Pneumocystis jirovecii pneumonia (PJP) remains an important cause of morbidity and mortality in non-HIV immunocompromised patients especially in transplant recipients. But its diagnosis remains challenging due to the insuffificient performance of conventional methods for diagnosing Pneumocystis jirovecii(P. jirovecii) infection. Therefore, the auxiliary diagnostic function of metagenomics next-generation sequencing (mNGS) in clinical practice is worth of exploring.

Method

34 non-HIV immunocompromised patients who were diagnosed as PJP by clinical manifestations, imaging findings, immune status of the host, and Methenamine silver staining were tested by mNGS from October 2018 to December 2020 in Sichuan Provincial People’s Hospital. The clinical performances of mNGS for P. jirovecii infection diagnosis were also evaluated with genome reads abundance and comparing with other traditional diagnostic methods.

Results

We diagnosed a total of 34 non-HIV PJP patients by the clinical composite diagnosis. Our data shows that, compared with the clinical microbiological test, the detection rate of mNGS for P. jirovecii in non-HIV infected PJP patients is significantly higher than that of Methenamine silver staining and serum 1-3-β-D-glucan. mNGS can be used as an auxiliary diagnostic tool to help diagnosis. The number of reads mapped to the genome of P. jirovecii and the duration of patients from onset to sampling collection were statistically significant between the two groups (Reads>100 and Reads ≤ 100) (8days vs. 23days, p=0.020). In addition, univariate analysis showed that C-reactive protein (15.8mg/L vs.79.56mg/L, p=0.016), lactate dehydrogenase (696U/l vs. 494U/l, p=0.030) and procalcitonin (0.09ng/ml vs. 0.59ng/ml, p=0.028) was also statistically significant between the two groups.

Conclusions

An effective detection rate was achieved in PJP patients using mNGS testing of bronchoalveolar lavage fluid (BALF) or blood. The study also confirmed that the abundance of reads of P. jirovecii is related to the interval between the onset and sample collection. And the inflammation status during simultaneous mNGS detection might determine the abundance of pathogens. Hence, we conclude that the mNGS strategy could benefit disease diagnosis as well as treatment when complicated clinical infections appeared.

Low-dose trimethoprim-sulfamethoxazole for the treatment of Pneumocystis jirovecii pneumonia (LOW-TMP): protocol for a phase III randomised, placebo-controlled, dose-comparison trial

INTRODUCTION

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic infection of immunocompromised hosts with significant morbidity and mortality. The current standard of care, trimethoprim-sulfamethoxazole (TMP-SMX) at a dose of 15-20 mg/kg/day, is associated with serious adverse drug events (ADE) in 20%-60% of patients. ADEs include hypersensitivity reactions, drug-induced liver injury, cytopenias and renal failure, all of which can be treatment limiting. In a recent meta-analysis of observational studies, reduced dose TMP-SMX for the treatment of PJP was associated with fewer ADEs, without increased mortality.

METHODS AND ANALYSIS

A phase III randomised, placebo-controlled, trial to directly compare the efficacy and safety of low-dose TMP-SMX (10 mg/kg/day of TMP) with the standard of care (15 mg/kg/day of TMP) among patients with PJP, for a composite primary outcome of change of treatment, new mechanical ventilation, or death. The trial will be undertaken at 16 Canadian hospitals. Data will be analysed as intention to treat. Primary and secondary outcomes will be compared using logistic regression adjusting for stratification and presented with 95% CI.

ETHICS AND DISSEMINATION

This study has been conditionally approved by the McGill University Health Centre; Ethics approval will be obtained from all participating centres. Results will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT04851015.

Prognostic implication of bronchoalveolar lavage fluid analysis in patients with Pneumocystis jirovecii pneumonia without human immunodeficiency virus infection

Background

The prognostic value of bronchoalveolar lavage (BAL) fluid analysis in non-human immunodeficiency virus (HIV)-infected patients with Pneumocystis jirovecii pneumonia (PJP) has not been well elucidated. We aimed to investigate the prognostic implication of BAL fluid analysis in non-HIV patients with PJP.

Methods

The data of 178 non-HIV patients diagnosed with PJP based on the results of the polymerase chain reaction assay of BAL fluid specimens between April 2018 and December 2020 were retrospectively reviewed. The clinical characteristics, laboratory findings, and BAL fluid analysis results of patients who died within 90 days after hospital admission were compared.

Results

Twenty patients (11.2%) died within 90 days from admission. The neutrophil count in BAL fluid was significantly higher (median 22.0%, interquartile range [IQR] 2.0–46.0% vs. median 6.0%, IQR 2.0–18.0%, P = 0.044), while the lymphocyte count was significantly lower (median 24.0%, IQR 7.0–37.0% vs. median 41.0%, IQR 22.5–60.5%, P = 0.001) in the non-survivor group compared with that in the survivor group. In the multivariate analysis, the C-reactive protein level (odds ratio [OR] 1.093, 95% confidence interval [CI] 1.020–1.170, P = 0.011) and a BAL fluid lymphocyte count of ≤ 30% (OR 3.353, 95% CI 1.101–10.216, P = 0.033) were independently associated with mortality after adjusting for albumin and lactate dehydrogenase levels.

Conclusion

A low lymphocyte count in BAL fluid may be a predictor of mortality in non-HIV patients with PJP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02041-8.

Metagenomic Next-Generation Sequencing Is Highly Efficient in Diagnosing Pneumocystis Jirovecii Pneumonia in the Immunocompromised Patients

Purposes

To explore the value of metagenomic next-generation sequencing (mNGS) in diagnosing pneumocystis jiroveciipneumonia (PJP) in the immunocompromised patients.

Methods

Data of 122 patients with PJP in an immunosuppressed state and 67 non-PJP patients were collected. The diagnostic efficacy of mNGS was compared with the conventional methods, including Gomori methenamine silver (GMS) staining and serum (1,3)-β-D-glucan (BDG). Changes of anti-microbial therapy for patients with PJP based on mNGS results were also reviewed.

Results

The diagnostic sensitivity of mNGS to PJP was higher than that of GMS and BDG (100% vs. 15 and 74.5%, p < 0.001). The diagnostic specificity (91.%) was lower than that of GMS (100%), and similar with BDG (89.6%). In addition to P. jirovecii, mNGS revealed co-pathogens like human β-herpesvirus 5, human γ-pesvirus 4, and some other opportunistic pathogens. The reads of mNGS were remarkably higher in BALF than in blood samples. Initial antimicrobial treatment was modified in 89.3% patients based on the mNGS results, and 74 cases (60.7%) were treated with anti-P. jirovecii therapy.

Conclusion

mNGS is highly efficient in diagnosing PJP and good at identifying pathogens in mixed infections.

Treatment With Reduced-Dose Trimethoprim-Sulfamethoxazole Is Effective in Mild to Moderate Pneumocystis jirovecii Pneumonia in Patients With Hematologic Malignancies

BACKGROUND

Recent studies have reported that reduced-dose trimethoprim-sulfamethoxazole (TMP-SMX) may be effective in the treatment of Pneumocystis jirovecii pneumonia (PJP), but data are lacking for patients with hematologic malignancies.

METHODS

This retrospective study included all adult hematologic patients with PJP between 2013 and 2017 at 6 Swedish university hospitals. Treatment with 7.5-15 mg TMP/kg/day (reduced dose) was compared with >15-20 mg TMP/kg/day (standard dose), after correction for renal function. The primary outcome was the change in respiratory function (Δpartial pressure of oxygen [PaO2]/fraction of inspired oxygen [FiO2]) between baseline and day 8. Secondary outcomes were clinical failure and/or death at day 8 and death at day 30.

RESULTS

Of a total of 113 included patients, 80 patients received reduced dose and 33 patients received standard dose. The overall 30-day mortality in the whole cohort was 14%. There were no clinically relevant differences in ΔPaO2/FiO2 at day 8 between the treatment groups, either before or after controlling for potential confounders in an adjusted regression model (-13.6 mm Hg [95% confidence interval {CI}, -56.7 to 29.5 mm Hg] and -9.4 mm Hg [95% CI, -50.5 to 31.7 mm Hg], respectively). Clinical failure and/or death at day 8 and 30-day mortality did not differ significantly between the groups (18% vs 21% and 14% vs 15%, respectively). Among patients with mild to moderate pneumonia, defined as PaO2/FiO2 >200 mm Hg, all 44 patients receiving the reduced dose were alive at day 30.

CONCLUSIONS

In this cohort of 113 patients with hematologic malignancies, reduced-dose TMP-SMX was effective and safe for treating mild to moderate PJP.

Active Surveillance Program to Increase Awareness on Invasive Fungal Diseases: the French RESSIF Network (2012 to 2018)

The French National Reference Center for Invasive Mycoses and Antifungals leads an active and sustained nationwide surveillance program on probable and proven invasive fungal diseases (IFDs) to determine their epidemiology in France. Between 2012 and 2018, a total of 10,886 IFDs were recorded. The incidence increased slightly over time (2.16 to 2.36/10,000 hospitalization days, P = 0.0562) in relation with an increase of fungemia incidence (1.03 to 1.19/10,000, P = 0.0023), while that of other IFDs remained stable. The proportion of ≥65-year-old patients increased from 38.4% to 45.3% (P < 0.0001). Yeast fungemia (n = 5,444) was due mainly to Candida albicans (55.6%) with stable proportions of species over time. Echinocandins became the main drug prescribed (46.7% to 61.8%), but global mortality rate remained unchanged (36.3% at 1 month). Pneumocystis jirovecii pneumonia (n = 2,106) was diagnosed mostly in HIV-negative patients (80.7%) with a significantly higher mortality than in HIV-positive patients (21.9% versus 5.4% at 1 month, P < 0.0001). Invasive aspergillosis (n = 1,661) and mucormycosis (n = 314) were diagnosed mostly in hematology (>60% of the cases) with a global mortality rate of 42.5% and 59.3%, respectively, at 3 months and significant changes in diagnosis procedure over time. More concurrent infections were also diagnosed over time (from 5.4% to 9.4% for mold IFDs, P = 0.0115). In conclusion, we observed an aging of patients with IFD with a significant increase in incidence only for yeast fungemia, a trend toward more concurrent infections, which raises diagnostic and therapeutic issues. Overall, global survival associated with IFDs has not improved despite updated guidelines and new diagnostic tools.

A Clinically Applicable Nomogram for Predicting the Risk of Invasive Mechanical Ventilation in Pneumocystis jirovecii Pneumonia

Objective

Pneumocystis jirovecii pneumonia (PCP) is a life-threatening disease associated with a high mortality rate among immunocompromised patient populations. Invasive mechanical ventilation (IMV) is a crucial component of treatment for PCP patients with progressive hypoxemia. This study explored the risk factors for IMV and established a model for early predicting the risk of IMV among patients with PCP.

Methods

A multicenter, observational cohort study was conducted in 10 hospitals in China. Patients diagnosed with PCP were included, and their baseline clinical characteristics were collected. A Boruta analysis was performed to identify potentially important clinical features associated with the use of IMV during hospitalization. Selected variables were further analyzed using univariate and multivariable logistic regression. A logistic regression model was established based on independent risk factors for IMV and visualized using a nomogram.

Results

In total, 103 patients comprised the training cohort for model development, and 45 comprised the validation cohort to confirm the model’s performance. No significant differences were observed in baseline clinical characteristics between the training and validation cohorts. Boruta analysis identified eight clinical features associated with IMV, three of which were further confirmed to be independent risk factors for IMV, including age (odds ratio [OR] 2.615 [95% confidence interval (CI) 1.110–6.159]; p = 0.028), oxygenation index (OR 0.217 [95% CI 0.078–0.604]; p = 0.003), and serum lactate dehydrogenase level (OR 1.864 [95% CI 1.040–3.341]; p = 0.037). Incorporating these three variables, the nomogram achieved good concordance indices of 0.829 (95% CI 0.752–0.906) and 0.818 (95% CI 0.686–0.950) in predicting IMV in the training and validation cohorts, respectively, and had well-fitted calibration curves.

Conclusions

The nomogram demonstrated accurate prediction of IMV in patients with PCP. Clinical application of this model enables early identification of patients with PCP who require IMV, which, in turn, may lead to rational therapeutic choices and improved clinical outcomes.

Immune alveolitis in interstitial lung disease: an attractive cytological profile in immunocompromised patients

Background

Bronchoalveolar lavage (BAL) is a major diagnostic tool in interstitial lung disease (ILD). Its use remains largely quantitative, usually focused on cell differential ratio. However, cellular morphological features provide additional valuable information. The significance of the “immune alveolitis” cytological profile, characterized by lymphocytic alveolitis with activated lymphocytes and macrophages in epithelioid transformation or foamy macrophages desquamating in cohesive clusters with lymphocytes, remains unknown in ILD. Our objective was to describe patients’ characteristics and diagnoses associated with an immune alveolitis profile in undiagnosed ILD.

Methods

We performed a monocentric retrospective observational study. Eligible patients were adults undergoing diagnostic exploration for ILD and whose BAL fluid displayed an immune alveolitis profile. For each patient, we collected clinical, radiological and biological findings as well as the final etiology of ILD.

Results

Between January 2012 and December 2018, 249 patients were included. Mean age was 57 ± 16 years, 140 patients (56%) were men, and 65% of patients were immunocompromised. The main etiological diagnosis was Pneumocystis pneumonia (PCP) (24%), followed by drug-induced lung disease (DILD) (20%), viral pneumonia (14%) and hypersensitivity pneumonitis (HP) (10%). All PCP were diagnosed in immunocompromised patients while HP was found in only 8% of this subgroup. DILD and viral pneumonia were also commonly diagnosed in immunocompromised patients (94% and 80%, respectively).

Conclusion

Our study highlights the additional value of BAL qualitative description in ILD. We suggest incorporating the immune alveolitis profile for the diagnosis and management of ILD, especially in immunocompromised patients, since it guides towards specific diagnoses.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01871-w.

Characteristics and Prognostic Factors of Non-HIV Immunocompromised Patients With Pneumocystis Pneumonia Diagnosed by Metagenomics Next-Generation Sequencing

Objective

The aim of this study was to evaluate the potential of metagenomic next-generation sequencing (mNGS) for the diagnosis of pneumocystis pneumonia (PCP) in patients with non-human immunodeficiency virus-infection and to discuss the clinical characteristics and identify prognostic factors associated with patients with non-HIV PCP.

Methods

Forty-six patients with PCP who were admitted in respiratory intensive care unit (ICU) between May 2018 and May 2020 were retrospectively reviewed. The subjects were divided into survivor and non-survivor groups according to the patients' outcome. Conventional methods and mNGS for detecting Pneumocystis jirovecii (P. jirovecii) were analyzed. The patients' demographics, comorbidities, laboratory parameters, and treatments were compared and evaluated in both groups to identify risk factors for mortality by using univariate and multivariate logistic regression.

Results

Metagenomic next-generation sequencing (mNGS) showed a satisfying diagnostic performance of 100% positive of detecting P. jirovecii from bronchoalveolar lavage (BAL) specimens in forty-six patients with non-HIV PCP, compared to only 15.2% for Gomori Methenamine silver (GMS) staining and 84.8% for Serum 1,3-beta-D-glucan (BDG). Among them, the mean age was 46.4-year-old (range 18–79-year-old) and mortality rate was 43.5%. The dominant underlying conditions were connective tissue diseases (34.8%), autoimmune kidney diseases (30.4%), followed by hematologic malignancies (10.9%), and solid organ transplantation (6.5%). A total of 38 cases (82.6%) received glucocorticoid and 19 cases (41.3%) used immunosuppressant within 3 months before diagnosed PCP. Multiple infections were very common, over two thirds' cases had mixed infections. Compared with survivors, non-survivors had a higher acute physiology and chronic health evaluation II (APACHE II) score (14.4 ± 4.8 vs. 10 ± 3.4), Procalcitonin (PCT) [ng/ml: 0.737 (0.122–1.6) vs. 0.23 (0.095–0.35)], lactic dehydrogenase (LDH) [U/L: 1372 (825.5–2150) vs. 739 (490.5–956)], and neutrophil-lymphocyte ratio (NLR) [21.6 (15.67–38.2) vs. 11.75 (5.1–15.52)], but had a lower PaO₂/FiO₂ ratio (mmHg:108.8 ± 42.4 vs. 150.5 ± 47.5), lymphocytes [×10⁹/L: 0.33 (0.135–0.615) vs. 0.69 (0.325–1.07)] and CD4+ T cells [cell/μl: 112 (53.5–264) vs. 255 (145–303.5)], all P < 0.05. Furthermore, we found non-survivors' PaO₂/FiO₂ ratio of day 3 and day 7 had not improved when compared with that of day one, and platelet level and NLR became worse. Multivariate analysis showed that other pathogens' co-infection (OR = 9.011, 95% CI was 1.052–77.161, P = 0.045) and NLR (OR = 1.283, 95% CI was 1.046–1.547, P = 0.017) were the independent risk factors of poor prognosis.

Conclusion

mNGS is a very sensitive diagnostic tool for identifying P. jirovecii in patients who are non-HIV immunocompromised. PCP in patients who are non-HIV infected is associated with a high rate of multiple infections and severe condition. Mixed infection and elevation of NLR were the independent risk factors of poor prognosis.

Pneumocystis jirovecii pneumonia in patients with previously untreated acute myeloid leukaemia

BACKGROUND

Several studies in immunocompromised patients, such as those with HIV infection, undergoing cancer chemotherapy or organ transplant, have led to the development of guidelines on the use of prophylaxis to prevent Pneumocystis jirovecii pneumonia (PJP), in these specific conditions. Instead, since the association between PJP and acute myeloid leukaemia (AML) is not clearly defined, the role of prophylaxis in patients with AML is not yet established.

METHODS

We retrospectively analysed 251 consecutive patients with newly diagnosed non-M3-AML, admitted at the Hematology Unit of University Tor Vergata in Rome, during the period 2010-2020. The aim of the study was to evaluate the incidence of PJP among AML patients during their first hospital admission, and to identify subjects at a high risk to develop PJP.

RESULTS

Among 251 consecutive patients with non-M3-AML, 67 bronchoalveolar lavages (BAL) were performed. PJP was proven in 11/67 (16.7%) subjects undergoing BAL (11 males, median age 71 years), with an incidence of 4.3%. The most common reason for BAL execution were radiological findings such as ground-glass opacities (6/11, 55%) and atypical patterns like consolidations and nodules (5/11, 45%). One patient died because of PJP after 11 days of trimethoprim/sulfamethoxazole therapy. In multivariate analysis older age and smoking habit were independent factors significantly associated with PJP (p = .021 and 0.017 respectively).

CONCLUSION

We conclude that PJP infection is not uncommon among patients with AML. If intensive chemotherapy is planned, physicians should be aware of this risk and prophylaxis should be considered, particularly in older patients.

Epidemiology and clinical impact of respiratory co-infections at diagnosis of Pneumocystis jirovecii Pneumonia

OBJECTIVES

To describe the epidemiology and clinical impact of respiratory co-infections at diagnosis of Pneumocystis jirovecii Pneumonia (PcP).

METHODS

A retrospective observational study was conducted between January 2011 and April 2019 to evaluate respiratory co-infections at diagnosis of PcP patients, in two tertiary care hospitals. Respiratory co-infection was defined by the identification of pathogens from P. jirovecii-positive samples.

RESULTS

Of the 7 882 respiratory samples tested for P. jirovecii during the 8-year study period, 328 patients with final diagnosis of PcP were included in this study. Mean age was 56.7 ± 14.9 years, 193 (58.8%) were male, 74 (22.6%) had a positive HIV serology, 125 (38.1%) had a viral co-infections, 76 (23.2%) a bacterial co-infections and 90-day mortality was 25.3%. In overall population, 90-Day mortality was independently associated with a solid tumor underlying disease (OR 11.8, 1.90-78, p=0.008), SOFA score at admission (OR 1.62, 1.34-2.05; p<0.001) and CMV respiratory co-infection (OR 3.44, 1.24-2.90; p=0.02). Among HIV-negative patients, respiratory CMV co-infection was associated with a worse prognosis, especially when treated with adjunctive corticosteroid therapy.

CONCLUSIONS

Respiratory CMV co-infection at diagnosis of PcP was independently associated with increased 90-day mortality, specifically in HIV-negative patients.

The mycological and molecular study of Pneumocystis jiroveci pneumonia among HIV and non-HIV immunocompromised patients hospitalized in pulmonary units in Guilan, Northern Iran

Background and Objectives

Pneumocystis jirovecii pneumonia (PJP) is a serious infection that usually affects those with a weak immune system. Since the prevalence of this infection in Iran and in the world is not clearly defined, the present study aimed to evaluate the incidence, clinical spectrum, and demographic characteristics of PJP among HIV and non-HIV immunocompromised patients.

Materials and Methods

Bronchoalveolar Lavage (BAL) specimens were obtained from 3 groups of immunocompromised patients, including acquired immunodeficiency syndrome (AIDS) patients, diabetic patients, and patients receiving immunosuppressive therapies. All were hospitalized in pulmonary units. The specimens were examined using microscopic methods (Giemsa and calcofluor white staining) and the nested-PCR technique based on mtLSU-rRNA gene.

Results

A total of 120 BAL samples were collected. From 12.5% (5 from 40) of HIV-infected patients, 5% (2 from 40) of patients receiving immunosuppressive therapies, and 2.5% (1 from 40) of diabetic patients Pneumocystis jiroveci was isolated. There was not any association between the prevalence of PJP and the patient's gender (p= 0.557) and age (p= 0.681). Fever and dyspnea (n=7, 87.5%), nonproductive cough and abnormal auscultation sound (n=5, 62.5%), and also chills and weight loss (n=2, 25%) were the documented clinical symptoms of PJP. Also, the results showed that none of the samples had positive results for P. jiroveci with microscopic tests while using the nested-PCR method 8 samples had positive results.

Conclusion

Since PJP often causes symptoms that are similar to other illnesses, such as the flu or tuberculosis, clinical and laboratory findings should be used simultaneously for making the final decision on drug administration.

Multiplex Real-Time Polymerase Chain Reaction on Sputum for the Diagnosis of Pneumocystis jirovecii Pneumonia in Children: A Retrospective Study

Background

Pneumocystis jirovecii pneumonia (PCP) is a serious opportunistic infection in immunocompromised children. Real-time polymerase chain reaction (PCR) is widely used for the diagnosis of PCP due to its good accuracy. However, the diagnostic performance of multiplex real-time PCR on sputum in children with PCP has never been explored.

Methods

Medical records of 63 consecutive pediatric patients were analyzed retrospectively, including 13 cases with PCP and 50 with non-PCP pneumonia. Pneumocystis jirovecii (P. jirovecii) and other co-pathogens detected by multiplex real-time PCR in sputum samples were summarized. Using clinical composite diagnosis as the reference standard, we further compared the diagnostic performance of multiplex real-time PCR to combined serological markers (1,3)-β-D-glucan plus lactate dehydrogenase. Additionally, modifications of antimicrobial treatment for pediatric PCP patients after the report of multiplex real-time PCR results were reviewed.

Results

In children with PCP, nonproductive cough and shortness of breath were more common, lymphocyte count in peripheral blood was markedly lower, and serum levels of (1,3)-β-D-glucan and lactate dehydrogenase were much higher than non-PCP group. Multiplex real-time PCR reached a sensitivity of 100% in diagnosing PCP, which was better than serum (1,3)-β-D-glucan plus lactate dehydrogenase (76.9%). Its specificity (98.0%) significantly surpassed serum (1,3)-β-D-glucan plus lactate dehydrogenase (84.4%). Furthermore, multiplex real-time PCR showed a good performance in identifying co-pathogens in sputum of pediatric PCP patients. Cytomegalovirus, Epstein–Barr virus and Streptococcus pneumoniae were the most common co-pathogens in these patients. Initial antimicrobial treatment was modified in 76.9% of children with PCP after the report of PCR results.

Conclusion

Multiplex real-time PCR on sputum is a diagnostic tool with good performance for the identification of P. jirovecii as well as co-pathogens in children with PCP. Sputum may be an alternative to bronchoalveolar lavage fluid for PCR assay in children when bronchoscopic examination is not feasible.

Metagenomic Next-Generation Sequencing for the Diagnosis of Pneumocystis jirovecii Pneumonia in Non-HIV-Infected Patients: A Retrospective Study

Introduction

This study aimed to evaluate the utility of metagenomic next-generation sequencing (mNGS) for the diagnosis of Pneumocystis jirovecii pneumonia (PJP) in non-human immunodeficiency virus-infected patients.

Methods

We conducted a retrospective study. A total of 60 non-human immunodeficiency virus-infected PJP patients and 134 patients diagnosed with non-PJP pneumonia were included. P. jirovecii and other co-pathogens identified by mNGS in bronchoalveolar lavage fluid and/or blood samples were analyzed. Using clinical composite diagnosis as the reference standard, we compared the diagnostic performance of mNGS in PJP with conventional methods, including Gomori methenamine silver staining and serum (1,3)-β-d-glucan. Modifications of antimicrobial treatment for PJP patients after the report of mNGS results were also reviewed.

Results

mNGS reached a sensitivity of 100% in diagnosing PJP, which was remarkably higher than Gomori methenamine silver staining (25.0%) and serum (1,3)-β-d-glucan (67.4%). The specificity of mNGS (96.3%) significantly surpassed serum (1,3)-β-d-glucan (81.4%). Simultaneous mNGS of bronchoalveolar lavage fluid and blood samples was performed in 21 out of 60 PJP patients, and it showed a concordance rate of 100% in detecting P. jirovecii. Besides, mNGS showed good performance in identifying co-pathogens of PJP patients, among which cytomegalovirus and Epstein-Barr virus were most commonly seen. Initial antimicrobial treatment was modified in 71.7% of PJP patients after the report of mNGS results.

Conclusion

mNGS is a useful diagnostic tool with good performance for the diagnosis of PJP and the detection of co-pathogens. mNGS of bronchoalveolar lavage fluid and/or blood samples is suggested in patients with presumptive diagnosis of PJP. Blood samples may be a good alternative to bronchoalveolar lavage fluid for mNGS when bronchoscopic examination is not feasible.

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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06144-1.

Awake Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome: Which Clinical Issues Should Be Taken Into Consideration

With the goal of protecting injured lungs and extrapulmonary organs, venovenous extracorporeal membrane oxygenation (VV-ECMO) has been increasingly adopted as a rescue therapy for patients with severe acute respiratory distress syndrome (ARDS) when conventional mechanical ventilation failed to provide effective oxygenation and decarbonation. In recent years, it has become a promising approach to respiratory support for awake, non-intubated, spontaneously breathing patients with respiratory failure, referred to as awake ECMO, to avoid possible detrimental effects associated with intubation, mechanical ventilation, and the adjunctive therapies. However, several complex clinical issues should be taken into consideration when initiating and implementing awake ECMO, such as selecting potential patients who appeared to benefit most; techniques to facilitating cannulation and maintain stable ECMO blood flow; approaches to manage pain, agitation, and delirium; and approaches to monitor and modulate respiratory drive. It is worth mentioning that there had also been some inherent disadvantages and limitations of awake ECMO compared to the conventional combination of ECMO and invasive mechanical ventilation. Here, we review the use of ECMO in awake, spontaneously breathing patients with severe ARDS, highlighting the issues involving bedside clinical practice, detailing some of the technical aspects, and summarizing the initial clinical experience gained over the past years.

Characteristics and risk factors for Pneumocystis jirovecii pneumonia in patients with idiopathic membranous nephropathy

Pneumocystis jirovecii pneumonia (PCP) is a life-threatening opportunistic infection in idiopathic membranous nephropathy (IMN) patients, who are treated with immunosuppressive drugs. However, the risk factors of infection and their prognosis are rarely investigated. We aimed to characterize the clinical manifestations of PCP in patients with IMN, and to understand their risk factors, so that we can provide early warnings to patients with high risk and potential poor prognosis. We conducted a retrospective observational study of IMN patients in a referral center in China, from Jan 2012 to Dec 2018. Clinical and laboratory data were collected separately at the time of IMN and PCP diagnosis. Patients with PCP were matched to those without by gender and age at a ratio of 1:4. The risk factors and prognostic factors were determined by univariate and multivariate logistic regression analysis. A total of 879 patients with IMN were included, with a median follow-up of 267 (interquartile range (IQR) 64,842) days. In total, 26 (2.96%) of them were diagnosed with PCP. The infection rate increased to 3.87% among patients who received corticosteroids, and it further increased to 5.49% in those received over 0.5mg/kg prednisone. Univariate analysis indicated that initial usage of corticosteroids, use of cyclophosphamide, reduced estimated glomerular filtration rate (eGFR), and higher 24-h proteinuria were related to the PCP susceptibility. Multivariate analysis revealed that corticosteroid treatment and reduced eGFR increased the risk of the Pneumocystis jirovecii infection. The case fatality rate of the PCP patients was 23.08%, and increased to 75% among patients requiring invasive ventilation. Univariate analysis indicated that pulmonary insufficiency, invasive ventilation, decreased eGFR, and increased lactate dehydrogenase at presentation were linked to poor prognosis. PCP is not rare in patients with IMN, especially those on corticosteroids, and presented with decreased eGFR. Considering the high case fatality rate, further studies are in need for prevention and management of these patients.

Prognostic impact of early adjunctive corticosteroid therapy in non-HIV oncology or haematology patients with Pneumocystis jirovecii pneumonia: A propensity score analysis

Purpose

While early adjunctive corticosteroid therapy (EACST) has been proven effective in HIV patients with Pneumocystis Jirovecii Pneumonia (PJP), data remains controversial concerning non-HIV oncology or haematology patients.

Methods

This retrospective study included cancer patients without HIV and with diagnosis of PJP admitted in a cancer referral centre, from January-1-2010 to March-31-2017. We compared 30-day and 1-year mortality rate, change in the respiratory item of the Sequential Organ Failure Assessment score(SOFA-_resp worsening), use of tracheal intubation between day-1 and day-5 of anti-pneumocystis therapy and occurrence of coinfections between patients with EACST and those with no or late corticosteroid therapy, using an inverse probability weighting propensity score-based (IPW) analysis.

Results

133 non-HIV oncology or haematology PJP patients were included (EACST n = 58, others n = 75). The main underlying conditions were haematological malignancies (n = 107, 80,5%), solid tumour (n = 27, 20,3%) and allogeneic stem cell transplantation (n = 17, 12,8%). Overall 30-day and 1-year mortality rate was 24,1% and 56,4%, respectively. IPW analysis found no difference on 30-day (HR = 1.45, 95% CI [0.7–3.04], p = 0.321) and 1-year (HR = 1.25, CI 95% [0.75–2.09], p = 0.39) mortality rate between groups.

Conclusion

No difference in SOFA-_resp worsening, tracheal intubation and coinfections was found between groups. Combination of EACST with anti-pneumocystis therapy in non-HIV onco-haematology PJP-patients was not associated with clinical improvement.

Using Routine Laboratory Markers and Immunological Indicators for Predicting Pneumocystis jiroveci Pneumonia in Immunocompromised Patients

Background

Pneumocystis jiroveci pneumonia (PJP) is the most common opportunistic infection in immunocompromised patients. The accurate prediction of PJP development in patients undergoing immunosuppressive therapy remains challenge.

Methods

Patients undergoing immunosuppressive treatment and with confirmed pneumocystis jiroveci infection were enrolled. Another group of matched patients with immunosuppressant treatment but without signs of infectious diseases were enrolled to control group.

Results

A total of 80 (40 PJP, 40 non-PJP) participants were enrolled from Tongji Hospital. None of the patients were HIV positive. The routine laboratory indicators, such as LYM, MON, RBC, TP, and ALB, were significantly lower in PJP patients than in non-PJP patients. Conversely, LDH in PJP patients was significantly higher than in non-PJP controls. For immunological indicators, the numbers of T, B, and NK cells were all remarkably lower in PJP patients than in non-PJP controls, whereas the functional markers such as HLA-DR, CD45RO and CD28 expressed on CD4⁺ or CD8⁺ T cells had no statistical difference between these two groups. Cluster analysis showing that decrease of host immunity markers including CD3⁺, CD4⁺ and CD8⁺ T cells, and increase of tissue damage marker LDH were the most typical characteristics of PJP patients. A further established model based on combination of CD8⁺ T cells and LDH showed prominent value in distinguishing PJP from non-PJP, with AUC of 0.941 (95% CI, 0.892-0.990).

Conclusions

A model based on combination of routine laboratory and immunological indicators shows prominent value for predicting the development of PJP in HIV-negative patients undergoing immunosuppressive therapy.

Characteristics and outcome according to underlying disease in non-AIDS patients with acute respiratory failure due to Pneumocystis pneumonia

In the non-AIDS group, several underlying conditions and immune defects could lead to different PCP presentations. This study compared PCP presentation and outcome according to the underlying disease. A secondary analysis of a previously published prospective observational study including 544 PCP patients was done. Only non-AIDS patients were included. Underlying disease was defined as chronic lymphocytic leukemia (CLL), organ transplantation, solid cancer, allogeneic hematopoietic stem cell transplant (AHSCT), other hematological diseases, and immunosuppressive treatment. Clinical characteristics and outcomes were compared between groups. Multiple correspondent analyses compared clinical characteristics at diagnosis. Day 30 mortality was analyzed. Three hundred and twenty-one patients were included in the study. The underlying diseases were hematological malignancy (n = 75), AHSCT (n = 14), CLL (n = 19), solid organ transplant (n = 94), solid tumor (n = 39), and immunosuppressive treatment (n = 57). Compared with other underlying diseases, PCP related to CLL was closer to PCP related to AIDS presentation (long duration of symptoms before diagnosis, high level of dyspnea, and low oxygen saturation at diagnosis). Day 30 mortality was associated with underlying disease, oxygen flow, and shock at ICU admission. PCP presentations may vary according to the underlying reason for immunosuppression. Response to treatment and adjuvant steroid therapy should be analyzed regarding this result.

Validation of the Pneumocystis pneumonia score in haematology patients with acute respiratory failure

Background

Pneumocystis pneumonia (PCP) is an important cause of acute respiratory failure (ARF) in immunocompromised patients, yet no actual clinical tool suitably identifies patients at risk. Recently, a multivariable prediction model has been proposed for haematology patients with ARF requiring intensive care unit (ICU) admission to assess the risk of PCP (PCP score). However, it has not yet been validated externally.

Methods

To validate the PCP score, a retrospective cohort study was conducted in two large designated haematology centres in Korea. One-hundred and forty haematology patients with ARF were admitted to ICU. They underwent aetiologic evaluations between July 2016 and June 2019. The predictive ability of the score was assessed with the receiver operating characteristic (ROC) curve analysis for both the discrimination and calibration of the score.

Results

Among the 141 patients, 13 (9.2%) were finally diagnosed of PCP. Although the median of PCP score in PCP group was higher than in non-PCP group (3.0 [interquartile range 0.0–4.0] vs. 2.0 [0.5–4.0]), the difference was not statistically significant (P = 0.679). The area under the ROC curve of the PCP score in our cohort was 0.535 (95% CI, 0.449–0.620), indicating no discriminatory ability. When using a cut-off of 3.0 the score, the result was 38.5% (95% CI, 13.9–68.4) sensitive and 7.03% (95% CI, 61.6–78.1) specific. The negative predictive value was 58.8% and positive predictive value was 59.8% for a 10% prevalence of PCP.

Conclusions

In this study, the PCP score was not useful to predict the risk of PCP in haematology patients with ARF. Further prospective validation studies are needed to validate the score’s use in routine clinical practice for the early diagnosis of PCP in haematology patients.

Evaluation of a commercial Loop-mediated Isothermal Amplification (LAMP) assay for rapid detection of Pneumocystis jirovecii

BACKGROUND

Various tools are obtainable for the detection of Pneumocystis jirovecii, among them qPCR promising highest sensitivity. A novel molecular method is commercially available, the loop-mediated isothermal amplification (LAMP) assay.

OBJECTIVES

We compared the performance of the LAMP eazyplex^® Pneumocystis jirovecii with the RealStar Pneumocystis jirovecii PCR 1.0 qPCR.

MATERIAL/METHODS

Overall, 162 lower respiratory tract specimens from 146 critically ill patients were investigated. LAMP assay and qPCR were carried out according to the manufacturer's recommendations. Positive results of the LAMP were described as time to positivity (TTP). The limit of detection (LOD) of the LAMP was analysed using 10-fold serial dilutions of a high positive P jirovecii respiratory sample. For each serial dilution, TTP of the LAMP was plotted against cycle threshold (Ct) values of the qPCR.

RESULTS

The LOD of the LAMP was determined to be approximately 4 × 10³ copies/mL. While the LAMP revealed 28 (17%) positive signals from 20 patients, by using qPCR 41 (25%) positive samples from 28 patients were identified. Overall agreement with qPCR was 92%. Five false-negative, one false-positive and nine invalid results were detected by the LAMP. Positive and negative predictive values were 96% each, and sensitivity and specificity were 84% and 99%, respectively. There was a low correlation between the TTP and the fungal load.

CONCLUSION

The LAMP is a time-saving and easy-to-perform method. It can be used as an alternative diagnostic method. However, for quantification purposes the qPCR is still the gold standard.

Identifying predictors for bacterial and fungal coinfection on chest computed tomography in patients with Pneumocystis pneumonia

BACKGROUND

Pneumocystis pneumonia (PCP) is a common opportunistic infection with high mortality in individuals with decreased immunity. Pulmonary coinfections with PCP are associated with poor prognosis. The study aims to identify radiological predictors for pulmonary coinfections in patients with PCP and risk factors for mortality.

METHODS

This is a retrospective, five-year study was conducted in a medical center, enrolling patients diagnosed with PCP, who received a chest computed tomography (CT) scan. The radiological findings and medical records of all participants were reviewed carefully by 2 independent doctors. Univariable and multivariable analysis was performed to identify radiological predictors for pulmonary coinfection and clinical risk factors for poor prognosis.

RESULTS

A total of 101 participants were included, of which 39 were HIV-infected and 62 were non-HIV-infected. In multivariable analysis, radiologic predictors on chest CT for coinfection with bacteria pneumonia included lack of ground glass opacity (adjusted odds ratio [aOR], 6.33; 95% confidence interval [CI], 2.03-19.77; p = 0.001) and presence of pleural effusion (aOR, 3.74; 95% CI, 1.27-10.99; p = 0.017). Predictors for fungal pneumonia included diffuse consolidation (adjusted OR, 6.27; 95% CI, 1.72-22.86; p = 0.005) and presence of pleural effusion (adjusted OR, 5.26; 95% CI, 1.44-19.17; p = 0.012). A significantly higher in-hospital mortality was associated with older age, recent corticosteroid exposure, cytomegalovirus coinfection, and acute respiratory failure.

CONCLUSION

Early identification of pulmonary coinfections in PCP using radiological features on the CT scans, will enable appropriate treatment which is crucial to improve the prognosis.

Burden of serious fungal infections in the Netherlands

Background

Fungal diseases have an ever‐increasing global disease burden, although regional estimates for specific fungal diseases are often unavailable or dispersed.

Objectives

Here, we report the current annual burden of life‐threatening and debilitating fungal diseases in the Netherlands.

Methods

The most recent available epidemiological data, reported incidence and prevalence of fungal diseases were used for calculations.

Results

Overall, we estimate that the annual burden of serious invasive fungal infections in the Netherlands totals 3 185 patients, including extrapulmonary or disseminated cryptococcosis (n = 9), pneumocystis pneumonia (n = 740), invasive aspergillosis (n = 1 283), chronic pulmonary aspergillosis (n = 257), invasive Candida infections (n = 684), mucormycosis (n = 15) and Fusarium keratitis (n = 8). Adding the prevalence of recurrent vulvo‐vaginal candidiasis (n = 220 043), allergic bronchopulmonary aspergillosis (n = 13 568) and severe asthma with fungal sensitisation (n = 17 695), the total debilitating burden of fungal disease in the Netherlands is 254 491 patients yearly, approximately 1.5% of the country's population.

Conclusion

We estimated the annual burden of serious fungal infections in the Netherlands at 1.5% of the population based on previously reported modelling of fungal rates for specific populations at risk. With emerging new risk groups and increasing reports on antifungal resistance, surveillance programmes are warranted to obtain more accurate estimates of fungal disease epidemiology and associated morbidity and mortality.