Pneumocystis carinii pneumonia in patients with hematologic malignancies: a descriptive study

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.

Incidence of Pneumocystis Jiroveci Pneumonia in Patients With ANCA-Associated Vasculitis Initiating Therapy With Rituximab or Cyclophosphamide

OBJECTIVE

This manuscript assesses the incidence of Pneumocystis jiroveci pneumonia (PJP) among patients receiving contemporary treatment regimens for antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and adverse events associated with PJP prophylaxis.

METHODS

Incident users of rituximab or cyclophosphamide for AAV were identified in the TriNetX electronic health records database from 2011 to 2022. The incidence rates (IRs) of PJP in the first 6 months of induction therapy with rituximab and/or cyclophosphamide and during postinduction maintenance therapy with rituximab were calculated. Cox proportional hazard models were used to estimate hazard ratios (HRs) and confidence intervals (CIs) for the risk of adverse events commonly associated with PJP prophylaxis.

RESULTS

We identified 1,461 AAV cases who received induction therapy with rituximab (69.7%), cyclophosphamide (18.9%), or both (11.4%). Prophylaxis prescribed within 30 days of induction included trimethoprim-sulfamethoxazole (30.7%), atovaquone (5.4%), dapsone (3.8%), and pentamidine (0.8%). During induction therapy, 10 cases of PJP were identified (IR 15.0 cases per 1,000 patient-years); no deaths occurred. In adjusted analyses, those who received prophylaxis had a higher risk of leukopenia (HR 3.1; 95% CI 1.1-8.6), rash (HR 1.9; 95% CI 1.0-3.6), and nephropathy (HR 2.6; 95% CI 1.3-5.1) than those who did not. During rituximab maintenance therapy (n = 709), five cases of PJP were identified (IR 2.1 cases per 1,000 person-years), one of whom died during the hospitalization associated with a PJP diagnosis.

CONCLUSION

Rates of PJP in patients with AAV were lower than previously observed, and few cases occurred during rituximab maintenance therapy. PJP prophylaxis was associated with adverse events.

The Impact of Corticosteroids on the Outcome of Fungal Disease: a Systematic Review and Meta-analysis

Purpose of Review

Corticosteroids have a complex relationship with fungal disease - risk for many, benefit for others. This systematic review aims to address the effect of corticosteroids on mortality and visual outcome in different fungal diseases.

Recent Findings

Corticosteroids are a risk factor of aspergillosis for patients who have COVID-19, and they also led to a worse outcome. Similarity, corticosteroids are a risk factor for candidemia and mucormycosis. Some researchers reported that using topical corticosteroid in keratitis was associated with worse visual outcome if fungal keratitis. Some studies showed that corticosteroids are linked to a negative outcome for non-HIV patients with Pneumocystis jirovecii pneumonia (PCP), in contrast to those with HIV and PCP.

Summary

In 59 references, we found that corticosteroid therapy showed a worse clinical outcome in invasive aspergillosis (IA) (HR: 2.50, 95%CI: 1.89-3.31, p < 0.001) and chronic pulmonary aspergillosis (CPA) (HR: 2.74, 95%CI: 1.48-5.06, p = 0.001), PCP without HIV infection (OR: 1.29, 95%CI: 1.09-1.53, p = 0.003), invasive candidiasis and candidaemia (OR: 2.13, 95%CI: 1.85-2.46, p < 0.001), mucormycosis (OR: 4.19, 95%CI: 1.74-10.05, p = 0.001) and early in the course of fungal keratitis (OR: 2.99, 95%CI: 1.14-7.84, p = 0.026). There was equivocal outcome in cryptococcal meningoencephalitis in AIDS and primary coccidioidomycosis, while corticosteroid therapy showed a better outcome in PCP in HIV-infected patients (RR: 0.62, 95%CI: 0.46-0.83, p=0.001) and fungal keratitis patients after keratoplasty surgery (OR: 0.01, 95%CI: 0.00-0.41, p = 0.041) and probably in cryptococcal meningoencephalitis in non-immunocompromised patients. A sub-analysis in invasive aspergillosis and CPA showed that use of more than 2 mg/kg/day of prednisolone equivalents per day is a significant factor in increasing mortality (HR: 2.94, 95%CI: 2.13-4.05, p < 0.001). Corticosteroid therapy during invasive fungal disease was usually associated with a slightly or greatly increased mortality or worse visual outcome (in fungal keratitis), with two disease exceptions. Avoiding the addition of corticosteroids, or minimising dose and duration in those who require them, is likely to improve the outcome of most life- and vision-threatening fungal diseases. This review provides a cornerstone for further research in exploring the accuracy of suitable dose and duration of corticosteroids treatment in fungal diseases.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12281-023-00456-2.

Impact of novel agent therapies on immune cell subsets and infectious complications in patients with relapsed/refractory multiple myeloma

Introduction

Infections are a leading cause of morbidity and mortality in patients with multiple myeloma (MM).

Methods

To examine the effects of modern second-generation novel agent therapy on immune cell subsets, in particular CD4+-T-cells, and infectious complications in patients with relapsed/refractory MM (RRMM), we conducted a prospective cohort study in 112 RRMM patients.

Results

Substantially decreased CD4+-T-cells <200/µl before initiation of relapse therapy were detected in 27.7% of patients and were associated with a higher number of previous lines of therapy. Relapse therapy with carfilzomib or pomalidomide showed a significant further decrease of CD4+-T-cells. All novel agents led to a significant decrease of B-cell counts. Overall, infections were frequent with 21.3% of patients requiring antibacterial therapy within the first 3 months of relapse therapy, 5.6% requiring hospitalization. However, in the setting of standard antimicrobial prophylaxis in RRMM patients with very low CD4+-T-cells, no significant association of CD4+T-cell count and an increased risk of infection could be detected.

Discussion

Our findings imply that reduced CD4+-T-cell numbers and infections are common in patients with RRMM. We also demonstrate an association with the number of previous therapies and certain substances suggesting an increased need for personalized prophylaxis strategies for opportunistic infections in this patient cohort.

Supplementary Role of Immunological Indicators in the Diagnosis and Prognosis of Pneumocystis Pneumonia in Non-HIV Immunocompromised Patients

Background

Pneumocystis pneumonia (PCP) has a high mortality in HIV-negative immunocompromised patients. The occurrence and development of PCP are believed to be correlated with the level of lymphocytes and their subsets. The aim of this study was to determine if the levels of lymphocyte subpopulations and immunoglobulin are associated with PCP.

Methods

A total of 74 immunocompromised patients were enrolled in this single-center cohort study. Diagnosis of PCP was based on the relevant pulmonary symptoms and radiological imaging, and the detection of Pneumocystis jirovecii in BAL fluid or biopsy tissue by metagenomic next-generation sequencing (mNGS). All patients were divided into two groups (PCP group and non-PCP group) and the patients in PCP group were then divided into two groupsbased on the outcome of the disease during the hospitalization.

Results

We observed a significant lower level of IgG (p=0.000) and B lymphocyte counts (p=0.017) in the PCP group comparing to that in the non-PCP group. CD4+ T cell counts, as well as the ratio of CD4+/CD8+ T cells in circulation and BAL fluid were also lower in the PCP group comparing to those in the non-PCP group. Lactate dehydrogenase (LDH) in the PCP group was significantly higher than that in the non-PCP group (p=0.029). In the PCP group, a lower level of total lymphocytes (p=0.004), T cells (p=0.001), CD4+ cells (p=0.001), and CD8+ cells (p=0.007), as well as the proportion of lymphocytes in BAL fluid (p=0.000) were found in deceased patients comparing to those in the survived group.

Conclusion

Our study revealed an important role of humoral immunity in the infection of Pneumocystis jirovecii. The level of B cells and IgG could be used as a supplement to predict the occurrence of PCP. The level of CD4+ and CD8+ lymphocytes was significantly correlated with the outcome of PCP.

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.

Glucocorticoid therapy in respiratory illness: bench to bedside

Each year, hundreds of millions of individuals are affected by respiratory disease leading to approximately 4 million deaths. Most respiratory pathologies involve substantially dysregulated immune processes that either fail to resolve the underlying process or actively exacerbate the disease. Therefore, clinicians have long considered immune-modulating corticosteroids (CSs), particularly glucocorticoids (GCs), as a critical tool for management of a wide spectrum of respiratory conditions. However, the complex interplay between effectiveness, risks and side effects can lead to different results, depending on the disease in consideration. In this comprehensive review, we present a summary of the bench and the bedside evidence regarding GC treatment in a spectrum of respiratory illnesses. We first describe here the experimental evidence of GC effects in the distal airways and/or parenchyma, both in vitro and in disease-specific animal studies, then we evaluate the recent clinical evidence regarding GC treatment in over 20 respiratory pathologies. Overall, CS remain a critical tool in the management of respiratory illness, but their benefits are dependent on the underlying pathology and should be weighed against patient-specific risks.

Non-HIV-infected patients with Pneumocystis pneumonia in the intensive care unit: A bicentric, retrospective study focused on predictive factors of in-hospital mortality

BACKGROUND

The incidence of Pneumocystis pneumonia (PCP) among patients without human immunodeficiency virus (HIV) infection continues to increase. Here, we identified potential risk factors for in-hospital mortality among HIV-negative patients with PCP admitted to the intensive care unit (ICU).

METHODS

We retrospectively analyzed medical records of 154 non-HIV-infected PCP patients admitted to the ICU at Peking Union Medical College Hospital (PUMCH) and China-Japan Friendship Hospital (CJFH) from October 2012 to July 2020. Clinical characteristics were examined, and factors related to in-hospital mortality were analyzed.

RESULTS

A total of 154 patients were enrolled in our study. Overall, the in-hospital mortality rate was 65.6%. The univariate analysis indicated that nonsurvivors were older (58 vs. 52 years, P = 0.021), were more likely to use high-dose steroids (≥1 mg/kg/day prednisone equivalent, 39.62% vs. 55.34%, P = 0.047), receive caspofungin during hospitalization (44.6% vs. 28.3%, P = 0.049), require invasive ventilation (83.2% vs. 47.2%, P < 0.001), develop shock during hospitalization (61.4% vs. 20.8%, P < 0.001), and develop pneumomediastinum (21.8% vs. 47.2%, P = 0.001) and had higher Acute Physiology and Chronic Health Evaluation (APACHE) II scores on ICU admission (20.32 vs. 17.39, P = 0.003), lower lymphocyte counts (430 vs. 570 cells/μl, P = 0.014), and lower PaO2/FiO2 values (mmHg) on admission (108 vs. 147, P = 0.001). Multivariate analysis showed that age (odds ratio [OR] 1.03; 95% confidence interval [CI] 1.00-1.06; P = 0.024), use of high-dose steroids (≥1 mg/kg/day prednisone equivalent) during hospitalization (OR 2.29; 95% CI 1.07-4.90; P = 0.034), and a low oxygenation index on admission (OR 0.99; 95% CI 0.99-1.00; P = 0.014) were associated with in-hospital mortality.

CONCLUSIONS

The mortality rate of non-HIV-infected patients with PCP was high, and predictive factors of a poor prognosis were advanced age, use of high-dose steroids (≥1 mg/kg/day prednisone equivalent) during hospitalization, and a low oxygenation index on admission. The use of caspofungin during hospitalization might have no contribution to the prognosis of non-HIV-infected patients with PCP in the ICU.

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.

On the Treatment of Pneumocystis jirovecii Pneumonia: Current Practice Based on Outdated Evidence

Pneumocystis jirovecii pneumonia (PCP) is a common opportunistic infection causing more than 400000 cases annually worldwide. Although antiretroviral therapy has reduced the burden of PCP in persons with human immunodeficiency virus (HIV), an increasing proportion of cases occur in other immunocompromised populations. In this review, we synthesize the available randomized controlled trial (RCT) evidence base for PCP treatment. We identified 14 RCTs that were conducted 25-35 years ago, principally in 40-year-old men with HIV. Trimethoprim-sulfamethoxazole, at a dose of 15-20 mg/kg per day, is the treatment of choice based on historical practice rather than on quality comparative, dose-finding studies. Treatment duration is similarly based on historical practice and is not evidence based. Corticosteroids have a demonstrated role in hypoxemic patients with HIV but have yet to be studied in RCTs as an adjunctive therapy in non-HIV populations. The echinocandins are potential synergistic treatments in need of further investigation.

Adjunctive corticosteroids may be associated with better outcome for non-HIV Pneumocystis pneumonia with respiratory failure: a systemic review and meta-analysis of observational studies

Background

Evidence supporting corticosteroids adjunctive treatment (CAT) for Pneumocystis jirovecii pneumonia (PCP) in non-HIV patients is highly controversial. We aimed to systematically review the literature and perform a meta-analysis of available data relating to the effect of CAT on mortality of PCP in non-HIV patients.

Methods

We searched Pubmed, Medline, Embase, and Cochrane database from 1989 through 2019. Data on clinical outcomes from non-HIV PCP were extracted with a standardized instrument. Heterogeneity was assessed with the I² index. Pooled odds ratios and 95% confidence interval were calculated using a fixed effects model. We analyzed the impact of CAT on mortality of non-HIV PCP in the whole PCP population, those who had hypoxemia (PaO₂ < 70 mmHg) and who had respiratory failure (PaO₂ < 60 mmHg).

Results

In total, 259 articles were identified, and 2518 cases from 16 retrospective observational studies were included. In all non-HIV PCP cases included, there was an association between CAT and increased mortality (odds ratio, 1.37; 95% confidence interval 1.07–1.75; P = 0.01). CAT showed a probable benefit of decreasing mortality in hypoxemic non-HIV PCP patients (odds ratio, 0.69; 95% confidence interval 0.47–1.01; P = 0.05). Furthermore, in a subgroup analysis, CAT showed a significantly lower mortality in non-HIV PCP patients with respiratory failure compared to no CAT (odds ratio, 0.63; 95% confidence interval 0.41–0.95; P = 0.03).

Conclusions

Our meta-analysis suggests that among non-HIV PCP patients with respiratory failure, CAT use may be associated with better clinical outcomes, and it may be associated with increased mortality in unselected non-HIV PCP population. Clinical trials are needed to compare CAT vs no-CAT in non-HIV PCP patients with respiratory failure. Furthermore, CAT use should be withheld in non-HIV PCP patients without hypoxemia.

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

Background

Pneumocystis jirovecii pneumonia (PJP) remains a severe disease associated with high rates of invasive mechanical ventilation (MV) and mortality. The objectives of this study were to assess early risk factors for severe PJP and 90-day mortality, including the broncho-alveolar lavage fluid cytology profiles at diagnosis.

Methods

We prospectively enrolled all patients meeting pre-defined diagnostic criteria for PJP admitted at Nantes university hospital, France, from January 2012 to January 2017. Diagnostic criteria for PJP were typical clinical features with microbiological confirmation of P. jirovecii cysts by direct examination or a positive specific quantitative real-time polymerase chain reaction (PCR) assay. Severe PJP was defined as hypoxemic acute respiratory failure requiring high-flow nasal oxygen with at least 50% FiO₂, non-invasive ventilation, or MV.

Results

Of 2446 respiratory samples investigated during the study period, 514 from 430 patients were positive for P. jirovecii. Of these 430 patients, 107 met criteria for PJP and were included in the study, 53 (49.5%) patients had severe PJP, including 30 who required MV. All patients were immunocompromised with haematological malignancy ranking first (n = 37, 35%), followed by solid organ transplantation (n = 27, 25%), HIV-infection (n = 21, 20%), systemic diseases (n = 13, 12%), solid tumors (n = 12, 11%) and primary immunodeficiency (n = 6, 8%). By multivariate analysis, factors independently associated with severity were older age (OR, 3.36; 95% CI 1.4–8.5; p < 0.05), a P. jirovecii microscopy-positive result from bronchoalveolar lavage (BAL) (OR, 1.3; 95% CI 1.54–9.3; p < 0.05); and absence of a BAL fluid alveolitis profile (OR, 3.2; 95% CI 1.27–8.8; p < 0.04). The 90-day mortality rate was 27%, increasing to 50% in the severe PJP group. Factors independently associated with 90-day mortality were worse SOFA score on day 1 (OR, 1.05; 95% CI 1.02–1.09; p < 0.001) whereas alveolitis at BAL was protective (OR, 0.79; 95% CI 0.65–0.96; p < 0.05). In the subgroup of HIV-negative patients, similar findings were obtained, then viral co-infection were independently associated with higher 90-day mortality (OR, 1.25; 95% CI 1.02–1.55; p < 0.05).

Conclusions

Older age and P. jirovecii oocysts at microscopic examination of BAL were independently associated with severe PJP. Both initial PJP severity as evaluated by the SOFA score and viral co-infection predicted 90-day mortality. Alveolitis at BAL examination was associated with less severe PJP. The pathophysiological mechanism underlying this observation deserves further investigation.

Pneumocystis jirovecii pneumonia in patients with acute myeloid leukaemia

The association of Pneumocystis jirovecii pneumonia (PJP) and acute myeloid leukaemia (AML) is not clearly defined. In our experience of 291 patients with AML, 20 (14 males and 6 females, median age 56) developed PJP (incidence 6.8%). Thirteen patients (65%) survived until discharge from hospital. We conclude that PJP is not uncommon among patients with AML. In clinical care of AML, awareness of PJP should be heightened and prophylaxis should be considered.

Risk factors for mortality from pneumocystis carinii pneumonia (PCP) in non-HIV patients: a meta-analysis

The number of patients with non-human immunodeficiency virus (HIV) related pneumocystis carinii pneumonia (PCP) is increasing with widespread immunosuppressive treatment. We performed a meta-analysis to describe the clinical characteristics and factors associated with outcomes of PCP in HIV-negative patients. A total of 13 studies including 867 patients with non-HIV related PCP was included. The overall mortality for non-HIV patients with PCP was 30.6%. The most common underlying disorder for the development of PCP is hematological malignancies (29.1%), followed by autoimmune disease (20.1%), organ or bone marrow transplantation (14.0%), and solid tumors (6.0%). Risk factors associated with increased mortality rate including old age, female sex, longer time from onset of symptoms to diagnosis, respiratory failure, solid tumors, high lactate dehydrogenase, low serum albumin, bacterial, and aspergillus co-infection, etc (P < 0.05). Adjunctive corticosteroid and PCP prophylaxis was not shown to improve the outcome of PCP in non-HIV patients (P > 0.05). Our findings indicate that mortality in non-HIV patients with PCP is high. Improved knowledge about the prognostic factors may guide the early treatment.

Low-dose trimethoprim-sulfamethoxazole treatment for pneumocystis pneumonia in non-human immunodeficiency virus-infected immunocompromised patients: A single-center retrospective observational cohort study

BACKGROUND/PURPOSE

The efficacy of low-dose trimethoprim-sulfamethoxazole (TMP-SMX) may be acceptable for the treatment of pneumocystis pneumonia (PCP) in non-human immunodeficiency virus (HIV)-infected patients, with a low incidence of adverse reactions. This study is aimed to evaluate the efficacy and safety of such a regimen for the treatment of non-HIV PCP.

METHODS

We retrospectively enrolled 24 consecutive patients diagnosed with non-HIV PCP who were treated with low-dose TMP-SMX (TMP, 4-10 mg/kg/day; SMX, 20-50 mg/kg/day). Data of the conventional-dose treatment were used as reference. The primary endpoints were the 30- and 180-day survival rates from the day of treatment, and secondary endpoints were the incidence of each adverse reaction and dropout rate from the initial TMP-SMX regimen. The survival rate was estimated using the Kaplan-Meier method with 95% confidence interval (CI).

RESULTS

The median age of patients was 72 years (54.2% men), and connective tissue disease was the most frequent underlying disease (66.7%) in the low-dose group. The 30- and 180-day survival rates were 95.8% (95% CI: 88.2-100.0%) and 91.0% (95% CI: 79.9%-100.0%), respectively, in the low-dose group and 69.0% (95% CI: 54.0%-88.0%) and 51.5% (95% CI: 36.1%-73.4%), respectively, in the conventional-dose group. The total adverse reaction rate was 58.3% in the low-dose group and 72.4% in the conventional-dose group. A total of 75.0% of patients in the low-dose group and 31.0% in the conventional-dose group completed treatment with the initial regimen.

CONCLUSION

Low-dose TMP-SMX may be a treatment option for patients with non-HIV PCP.

The role of CD4 cell count as discriminatory measure to guide chemoprophylaxis against Pneumocystis jirovecii pneumonia in human immunodeficiency virus-negative immunocompromised patients: A systematic review

BACKGROUND

In recent years, the incidence of Pneumocystis jirovecii pneumonia (PJP) has increased in immunocompromised patients without human immunodeficiency virus (HIV) infection. Chemoprophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX) is highly effective in preventing PJP in both HIV-positive and -seronegative patients. In HIV-positive patients, the risk of PJP is strongly correlated with decreased CD4 cell count. The role of CD4 cell count in the pathogenesis of PJP in non-HIV immunocompromised patients is less well studied. For most immunosuppressive conditions, no clear guidelines indicate whether to start TMP-SMX.

METHOD

We conducted a systematic literature review with the aim to provide a comprehensive overview on the role of CD4 cell counts in managing the risk of PJP in HIV-seronegative patients.

RESULTS

Of the 63 individual studies retrieved, 14 studies report on CD4 cell counts in a variety of immunosuppressive conditions. CD4 cell count were <200/μL in 73.1% of the patients.

CONCLUSION

CD4 cell count <200/μL is a sensitive biomarker to identify non-HIV immunocompromised patients who are at risk for PJP. Measuring CD4 cell counts could help clinicians identify patients who may benefit from TMP-SMX prophylaxis.

Copy Number Variation of Mitochondrial DNA Genes in Pneumocystis jirovecii According to the Fungal Load in BAL Specimens

Pneumocystis jirovecii is an unculturable fungus and the causative agent of Pneumocystis pneumonia, a life-threatening opportunistic infection. Although molecular diagnosis is often based on the detection of mtLSU rRNA mitochondrial gene, the number of copies of mitochondrial genes had not been investigated. We developed and optimized six real-time PCR assays in order to determine the copy number of four mitochondrial genes (mtSSU rRNA, mtLSU rRNA, NAD1, and CYTB) in comparison to nuclear genome (DHPS and HSP70) and tested 84 bronchoalveolar fluids of patients at different stages of the infection. Unexpectedly, we found that copy number of mitochondrial genes varied from gene to gene with mtSSU rRNA gene being more represented (37 copies) than NAD1 (23 copies), mtLSU rRNA (15 copies) and CYTB (6 copies) genes compared to nuclear genome. Hierarchical clustering analysis (HCA) allowed us to define five major clusters, significantly associated with fungal load (p = 0.029), in which copy number of mitochondrial genes was significantly different among them. More importantly, copy number of mtLSU rRNA, NAD1, and CYTB but not mtSSU rRNA differed according to P. jirovecii physiological state with a decreased number of copies when the fungal load is low. This suggests the existence of a mixture of various subspecies of mtDNA that can harbor different amplification rates. Overall, we revealed here an unexpected variability of P. jirovecii mtDNA copy number that fluctuates according to P. jirovecii’s physiological state, except for mtSSU that is the most stable and the most present mitochondrial gene.

Adjunctive Corticosteroids for Pneumocystis jirovecii Pneumonia in Non-HIV-infected Patients: A Systematic Review and Meta-analysis of Observational Studies

INTRODUCTION

The clinical benefits of adjunctive corticosteroids for Pneumocystis jirovecii (P. jirovecii) pneumonia in patients not infected with the human immunodeficiency virus (HIV) has not been evaluated by meta-analysis.

METHODS

We conducted a systematic review of published studies describing the effects of adjunctive corticosteroids on outcome in non-HIV P. jirovecii pneumonia patients. Two investigators independently searched the PubMed and Cochrane databases for eligible articles written in English. A meta-analysis was performed using a random-effects model for measuring mortality as the primary outcome, and the need for intubation or mechanical ventilation as the secondary outcome.

RESULTS

Seven observational studies were eligible. In these studies, adjunctive corticosteroids did not affect mortality in non-HIV patients (odds ratio [OR] 1.26; 95% CI 0.60-2.67) and there was no beneficial effect in patients with severe hypoxemia (PaO₂<70mmHg) (OR 0.90; 95% CI 0.44-1.83). No significant effect on the secondary outcome was observed (OR 1.34; 95% CI 0.44-4.11).

CONCLUSIONS

Although the studies were observational, meta-analysis showed that adjunctive corticosteroids did not improve the outcome of P. jirovecii pneumonia in non-HIV patients. The results warrant a randomized controlled trial.

Diversity of Pneumocystis jirovecii during Infection Revealed by Ultra-Deep Pyrosequencing

Pneumocystis jirovecii is an uncultivable fungal pathogen responsible for Pneumocystis pneumonia (PCP) in immunocompromised patients, the physiopathology of which is only partially understood. The diversity of the Pneumocystis strains associated with acute infection has mainly been studied by Sanger sequencing techniques precluding any identification of rare genetic events (< 20% frequency). We used next-generation sequencing to detect minority variants causing infection, and analyzed the complexity of the genomes of infection-causing P. jirovecii. Ultra-deep pyrosequencing (UDPS) of PCR amplicons of two nuclear target region [internal transcribed spacer 2 (ITS2) and dihydrofolate reductase (DHFR)] and one mitochondrial DNA target region [the mitochondrial ribosomal RNA large subunit gene (mtLSU)] was performed on 31 samples from 25 patients. UDPS revealed that almost all patients (n = 23/25, 92%) were infected with mixtures of strains. An analysis of repeated samples from six patients showed that the proportion of each variant change significantly (by up to 30%) over time on treatment in three of these patients. A comparison of mitochondrial and nuclear UDPS data revealed heteroplasmy in P. jirovecii. The recognition site for the homing endonuclease I-SceI was recovered from the mtLSU gene, whereas its two conserved motifs of the enzyme were not. This suggests that heteroplasmy may result from recombination induced by unidentified homing endonucleases. This study sheds new light on the biology of P. jirovecii during infection. PCP results from infection not with a single microorganism, but with a complex mixture of different genotypes, the proportions of which change over time due to intricate selection and reinfection mechanisms that may differ between patients, treatments, and predisposing diseases.

ECIL guidelines for treatment of Pneumocystis jirovecii pneumonia in non-HIV-infected haematology patients

The initiation of systemic antimicrobial treatment of Pneumocystis jirovecii pneumonia (PCP) is triggered by clinical signs and symptoms, typical radiological and occasionally laboratory findings in patients at risk of this infection. Diagnostic proof by bronchoalveolar lavage should not delay the start of treatment. Most patients with haematological malignancies present with a severe PCP; therefore, antimicrobial therapy should be started intravenously. High-dose trimethoprim/sulfamethoxazole is the treatment of choice. In patients with documented intolerance to this regimen, the preferred alternative is the combination of primaquine plus clindamycin. Treatment success should be first evaluated after 1 week, and in case of clinical non-response, pulmonary CT scan and bronchoalveolar lavage should be repeated to look for secondary or co-infections. Treatment duration typically is 3 weeks and secondary anti-PCP prophylaxis is indicated in all patients thereafter. In patients with critical respiratory failure, non-invasive ventilation is not significantly superior to intubation and mechanical ventilation. The administration of glucocorticoids must be decided on a case-by-case basis.

Pneumonia in the neutropenic cancer patient

PURPOSE OF REVIEW

Pneumonia is the leading cause of death among neutropenic cancer patients, particularly those with acute leukaemia. Even with empiric therapy, case fatality rates of neutropenic pneumonias remain unacceptably high. However, recent advances in the management of neutropenic pneumonia offer hope for improved outcomes in the cancer setting. This review summarizes recent literature regarding the clinical presentation, microbiologic trends, diagnostic advances and therapeutic recommendations for cancer-related neutropenic pneumonia.

RECENT FINDINGS

Although neutropenic patients acquire pathogens both in community and nosocomial settings, patients' obligate healthcare exposures result in the frequent identification of multidrug-resistant bacterial organisms on conventional culture-based assessment of respiratory secretions. Modern molecular techniques, including expanded use of galactomannan testing, have further facilitated identification of fungal pathogens, allowing for aggressive interventions that appear to improve patient outcomes. Multiple interested societies have issued updated guidelines for antibiotic therapy of suspected neutropenic pneumonia. The benefit of antibiotic medications may be further enhanced by agents that promote host responses to infection.

SUMMARY

Neutropenic cancer patients have numerous potential causes for pulmonary infiltrates and clinical deterioration, with lower respiratory tract infections among the most deadly. Early clinical suspicion, diagnosis and intervention for neutropenic pneumonia provide cancer patients' best hope for survival.

New Short Tandem Repeat-Based Molecular Typing Method for Pneumocystis jirovecii Reveals Intrahospital Transmission between Patients from Different Wards

Pneumocystis pneumonia is a severe opportunistic infection in immunocompromised patients caused by the unusual fungus Pneumocystis jirovecii. Transmission is airborne, with both immunocompromised and immunocompetent individuals acting as a reservoir for the fungus. Numerous reports of outbreaks in renal transplant units demonstrate the need for valid genotyping methods to detect transmission of a given genotype. Here, we developed a short tandem repeat (STR)-based molecular typing method for P. jirovecii. We analyzed the P. jirovecii genome and selected six genomic STR markers located on different contigs of the genome. We then tested these markers in 106 P. jirovecii PCR-positive respiratory samples collected between October 2010 and November 2013 from 91 patients with various underlying medical conditions. Unique (one allele per marker) and multiple (more than one allele per marker) genotypes were observed in 34 (32%) and 72 (68%) samples, respectively. A genotype could be assigned to 55 samples (54 patients) and 61 different genotypes were identified in total with a discriminatory power of 0.992. Analysis of the allelic distribution of the six markers and minimum spanning tree analysis of the 61 genotypes identified a specific genotype (Gt21) in our hospital, which may have been transmitted between 10 patients including six renal transplant recipients. Our STR-based molecular typing method is a quick, cheap and reliable approach to genotype Pneumocystis jirovecii in hospital settings and is sensitive enough to detect minor genotypes, thus enabling the study of the transmission and pathophysiology of Pneumocystis pneumonia.

Efficacy and tolerability of intravenous pentamidine isethionate for Pneumocystis jiroveci prophylaxis in a pediatric oncology population

Cancer therapy routinely requires Pneumocystis jiroveci prophylaxis. In those intolerant of trimethoprim/sulfamethoxazole, aerosolized pentamidine is convenient and effective. Intravenous pentamidine is often substituted in young children but its efficacy remains controversial. In this retrospective study of a large pediatric oncology cohort, we confirm intravenous pentamidine to be effective and well-tolerated as second-line prophylaxis across all ages.

Management ofPneumocystispneumonia in patients with inflammatory disorders

Pneumocystis jirovecii is an atypical fungus that causes Pneumocystis pneumonia in immunocompromised patients. Underlying diseases associated with Pneumocystis pneumonia mainly consist of hematologic malignancies, solid tumors, organ transplant recipients and inflammatory disorders. Currently, inflammatory disorders represent 20% of underlying diseases. Corticosteroids are considered as a major risk factor. Recently introduced immunosuppressive drugs, such as antitumor necrosis factor monoclonal antibodies, could enhance the risk of Pneumocystis pneumonia. In patients with inflammatory disorders, lymphopenia is probably a determining factor but CD4+ T-cell count associated with the risk of Pneumocystis pneumonia remains unassessed. The diagnosis is based upon clinical, radiologic and biologic data. The identification of P. jirovecii usually requires a lower respiratory tract specimen, even if oral washes samples seem to be promising. According to recent data, immunofluorescent stains should be considered as the new gold standard, and specialized techniques such as PCR should be applied for sputum samples or oral washes. Recommendations on prophylaxis remains controversial except in patients with Wegener's granulomatosis and systemic lupus erythematosus. Cotrimoxazole is the preferred agent for prophylaxis as well as for treatment. An adjunctive corticosteroid therapy is usually prescribed despite the lack of evidence for utility in patients with inflammatory disorders. As person-to-person transmission is the most likely mode of acquiring P. jirovecii, isolation precautions should be advised.

Pneumocystis jerovecii pneumonia in a patient with untreated chronic lymphocytic leukaemia: a novel case and postulations concerning the mechanism

Chronic lymphocytic leukaemia (CLL), even when severe, is not directly associated with opportunistic infections. Opportunistic infections that occur with CLL are almost exclusively related to immunosuppression caused by chemotherapeutic drugs used to treat CLL. We report a case of Pneumocystis jirovecii (PJ) pneumonia that occurred in a patient with untreated CLL with pulmonary involvement. We suspect that PJ pneumonia resulted from an inadequate immune response in the lung parenchyma resulting from excessive local accumulation of CLL cells.

[Pneumocystis: epidemiology and molecular approaches]

Pneumocystosis is a common opportunistic infection in immunocompromised patients, especially in AIDS patients. The diagnosis of this pneumonia has presented several difficulties due to the low sensitivity of conventional staining methods and the absence of culture system for Pneumocystis. The molecular biology techniques, especially the PCR, have improved the detection of DNA of this fungus in invasive and noninvasive samples, and in the environment which highlighted human transmission and the existence of environmental source of Pneumocystis. In addition, various molecular biology techniques were used for typing of Pneumocystis strains, especially P. jirovecii, which is characterized by a significant genetic biodiversity. Finally, the widespread use of cotrimoxazole for the treatment and prophylaxis of pneumocystosis has raised questions about possible resistance to sulfa drugs in P. jirovecii.

Utility of bronchoalveolar lavage in the diagnosis of pulmonary infection in children with haematological malignancies

BACKGROUND

Fibre-optic bronchoscopy with bronchoalveolar lavage (BAL) is a safe procedure and is associated with low morbidity and mortality in immunocompromised children. Although many studies have highlighted the advantages of positive BAL results in the diagnosis of pulmonary infections, there have been few reports examining the impact of a negative BAL result on clinical management in immunocompromised children on empiric broad-spectrum antimicrobial therapy.

AIM

The aim of this study was to evaluate BAL in the diagnosis of pulmonary infections in children with haematological malignancies who develop pneumonia unresponsive to empiric antimicrobial therapy, and also to determine whether a negative BAL result contributed to the clinical management of these patients.

MATERIALS AND METHODS

A retrospective review of 44 BAL procedures performed in 33 children with haematological malignancy diagnosed and treated at Our Lady's Children Hospital, Crumlin, Dublin 12, Ireland, over a 10-year period was carried out.

RESULTS

We identified a pathogen causing pneumonia in 24 of 44 BAL procedures (54.5 %). The BAL procedure resulted in modification of antimicrobial treatment after 20 of 24 procedures with positive results (83.3 %) in 16 of 20 patients (80 %). Management was changed after 8 of 20 procedures with negative results (40 %) in 8 of 18 patients (44.4 %). The procedure was well tolerated in all patients.

CONCLUSIONS

Our study supports the use of bronchoscopy with BAL as a diagnostic intervention in this patient population. We consider BAL a safe procedure from which both positive and negative results contribute to the patient's clinical management.

Outcome of Pneumocystis jirovecii pneumonia diagnosed by polymerase chain reaction in patients without human immunodeficiency virus infection

BACKGROUND AND OBJECTIVE

Pneumonia caused by Pneumocystis jirovecii (PCP) in patients without human immunodeficiency virus (HIV) infection is associated with high mortality. The diagnosis of PCP at our institution is based on detection of DNA using a polymerase chain reaction (PCR) assay. The aim of this study was to describe the clinical manifestations, outcomes and factors associated with mortality due to PCP, as diagnosed by PCR, in patients without HIV infection.

METHODS

Over a 6-year period, all HIV-negative immunocompromised patients suspected of having an opportunistic pulmonary infection underwent diagnostic bronchoscopy. A multigene PCR assay that detects Pneumocystis jirovecii DNA was used for the diagnosis of PCP. Patients were considered to have PCP if they had underlying immunodeficiency, compatible signs and symptoms, abnormal radiological findings, and Pneumocystis jirovecii DNA was detected in a bronchoalveolar lavage fluid sample. Data was collected retrospectively.

RESULTS

PCP was diagnosed in 58 patients. The underlying conditions included haematological malignancies (60.3%), solid tumours (17.2%) and immunosuppressive treatment (22.4%). The most common clinical features in patients with PCP were fever (94.6%), dyspnoea (67.2%) and cough (36.2%). The overall in-hospital mortality was 17.2% (10/58). Mortality was associated with co-infections, high lactate dehydrogenase levels, female gender, and higher pneumonia severity index and acute physiology and chronic health evaluation III scores.

CONCLUSIONS

In this study, the mortality of HIV-negative patients with PCP was low compared with previous reports. We hypothesize that this finding resulted from the increased sensitivity of a PCR-based assay, as compared with traditional methods, for the diagnosis of PCP in HIV-negative patients.

Pneumocystis jirovecii pneumonia in non-HIV-infected patients: new risks and diagnostic tools

PURPOSE OF REVIEW

Non-HIV-infected populations are increasingly identified as being at risk for developing Pneumocystis jirovecii pneumonia (PJP). These patients typically present with severe disease and poorly tolerate invasive diagnostic procedures. This review examines recently reported risks for PJP in non-HIV populations and summarizes new diagnostic techniques.

RECENT FINDINGS

PJP is associated with immunomodulatory drug therapies, including monoclonal antibody therapies such as tumour necrosis factor α antagonists, and calcineurin inhibitors. Underlying disease states include solid-organ transplantation, connective tissue and rheumatologic disorders, inflammatory bowel disease, haematological malignancies, and solid tumours. Modern diagnostic techniques [conventional PCR, quantitative PCR, (1→3)-β-D-glucan assays, and PET] are reviewed with respect to predictive value and clinical utility. In particular, current literature regarding validation and specificity of molecular diagnostic techniques is summarized, including application to minimally invasive specimens.

SUMMARY

HIV-negative populations at risk for PJP can be identified. Conventional PCR increases diagnostic sensitivity but may detect asymptomatic colonization. Quantitative PCR demonstrates potential for distinguishing colonization from infection, but clinical validation is required. Serum (1→3)-β-D-glucan may be elevated in PJP, although standardized cut-off values for clinical infection have not been determined. Further validation of serum markers and molecular diagnostic methods is necessary for early and accurate diagnosis in non-HIV populations.

Risk factors for Pneumocystis jirovecii pneumonia in patients with lymphoproliferative disorders

BACKGROUND

Guidelines for primary Pneumocystis jirovecii pneumonia (PCP) prophylaxis for patients with hematologic malignancy (HM) are still lacking. Our objective was to identify risk factors for PCP among patients with HM to help recognize patients who would benefit from primary PCP prophylaxis.

MATERIAL AND METHODS

We performed a case-control study of adult patients with HM and negative for human immunodeficiency virus and with confirmed PCP by using cytology or histopathology from 2 medical centers over an 11-year period. Each case was matched with 4 patients without PCP by type of HM and year of treatment. We compared demographic, clinical, and laboratory data among cases and controls. Data were analyzed by using SPSS version 18.0.

RESULTS

Fourteen cases and 56 controls were included in the study period. No significant differences were seen in demographics between both groups. All identified patients had lymphoproliferative HM, the majority of patients (93%) had either non-Hodgkin lymphoma or chronic lymphocytic leukemia. Autoimmune diseases were more frequent in cases vs. controls (28.6% vs. 5.4% P = .01). The receipt and duration of chemotherapy were similar in both groups. Among chemotherapeutic agents, including steroids, only fludarabine was associated with increased risk for PCP (50% vs. 17.9%; P = .02). No difference was found in total or lymphocyte percentage in cases at the time of PCP diagnosis vs. nadir values in controls.

CONCLUSION

Patients with lymphoproliferative HM, specifically chronic lymphocytic leukemia and non-Hodgkin lymphoma, who are receiving fludarabine and with autoimmune disorders are at increased risk for PCP and should be considered for PCP primary prophylaxis.

[Pneumocystis jirovecii pneumonia in non-HIV infected patients: a study of 41 cases]

BACKGROUND

The increasing use of immunosuppressive and cytotoxic therapies leads to a growing number of opportunistic infections especially Pneumocystis jirovecii pneumonia (PCP). The purpose of our study was to describe the population involved, and to assess clinical, biological, and mortality data.

METHODS

We collected retrospectively the whole medical file of all PCP cases diagnosed in non-HIV infected patients, in two French University Hospitals in the last decade (1999-2009). Diagnosis was made on standard coloration and/or immunofluorescence analysis of bronchoalveolar lavage fluid (BAL).

RESULTS

Forty-one patients were included in the study, mean age 56 (±12.5) years, sex ratio 0.71 men/woman. Underlying diseases were as follow: 12 patients (29%) were renal transplant recipients, 13 (32%) were treated for solid cancers, and 16 (39%) suffered from various diseases (three allogenic bone-marrow transplantation, 11 hematological malignancies, one pulmonary transplantation, one vasculitis). Twelve patients died (i.e. 29%). Median lymphocyte count was 542/mm(3). More than 85% patients received corticosteroids at a median cumulative 6-month dose of 2700mg. Seven patients (17%) had a PCP prophylaxis. Clinical worsening at day 5 (P<0.003), poor control of the underlying disease (P<0.015), WHO performans status superior than 2 (P<0.025), high temperature (P<0.04), and high oxygen flow (P<0.042) were linked to a poor prognosis.

DISCUSSION/CONCLUSION

The prognosis factors found are mostly linked to the patients' clinical severity. We would like to highlight: first, near to 30% mortality rate, secondly, a lack of prophylaxis in 34 patients, reflecting the difficulty to define PCP's risk in non HIV-infected patients.

Outcomes of moderate-to-severe Pneumocystis pneumonia treated with adjunctive steroid in non-HIV-infected patients

While it is well-known that adjunctive corticosteroid use improves the outcome of moderate-to-severe Pneumocystis jirovecii pneumonia (PcP) in patients with human immunodeficiency virus (HIV), there are limited data on its efficacy in non-HIV-infected patients with PcP. Patients undergoing fiber-optic bronchoscopy with bronchoalveolar lavage for suspected PcP from January 2007 through December 2010 were reviewed retrospectively. We compared demographics, clinical characteristics, and outcomes in 88 non-HIV-infected patients with moderate-to-severe PcP with (n = 59) and without (n = 29) adjunctive corticosteroid use. Outcomes of PcP were assessed by respiratory failure and 30-day and 90-day all-cause mortality. Survival curves were analyzed by the Kaplan-Meier method and estimated by the log rank test. All-cause mortality of moderate-to-severe PcP at 90 days was lower in the solid-organ transplant recipients than in all other patients (6/26 [23%] versus 34/62 [55%], respectively; P = 0.006), and mortality at 30 days was lower in patients with hematologic malignancies than in all other patients (4/26 [15%] versus 24/62 [39%], respectively; P = 0.03). The outcomes of PcP were not significantly different in moderate-to-severe PcP patients with and without adjunctive corticosteroid use, regardless of recent corticosteroid use. Survival analysis of PcP patients with and without corticosteroid use by the Kaplan-Meier method also did not reveal any difference (log rank test; P = 0.81). There again was no difference within the subgroup of PcP patients with solid-organ transplants. Adjunctive corticosteroid use may not improve the outcome of moderate-to-severe PcP in non-HIV-infected patients.

Prognostic value of C-reactive protein in HIV-infected patients with Pneumocystis jirovecii pneumonia

C-reactive protein (CRP) is a sensitive marker of inflammation and tissue damage. We aimed to describe CRP responses in HIV-infected patients presenting with Pneumocystis pneumonia (PCP), bacterial pneumonia (BP) and pulmonary tuberculosis (TB) and, in patients with PCP, to identify if elevated CRP has prognostic significance. Data obtained by case-note review of consecutive HIV-infected adults with acute respiratory episodes included admission CRP (elevated >5 mg/L), haemoglobin, white blood count, CD4 count and partial pressure of oxygen in the blood (PaO(2)), presence of pulmonary co-pathology/intercurrent infection and outcome (survival). Median (range) CRP in patients with BP = 120 mg/L (<5-620 mg/L), TB = 44 mg/L (<5-256.3 mg/L) and PCP = 35 mg/L (<5-254 mg/L). CRP was elevated in 93/103 (90.3%) patients with PCP; six patients died; and all had an elevated CRP. PaO(2) and CRP values were associated as follows: average CRP levels declined by 10% (95% confidence interval [CI] 0.20%) per kPa increase in PaO(2) = 0.002. Factors associated with death were higher CRP, odds ratio (OR) (95% CI) = 5.30 (1.61 to 17.51) per 100 mg/L increase, P = 0.006 and haemoglobin, OR (95% CI) = 0.52 (0.29 to 0.93) per g/dL, P = 0.033. CRP is elevated in the majority of HIV-infected patients with PCP, BP and TB. Admission CRP measurement lacks specificity, but in PCP elevations of CRP are associated with disease severity (PaO(2)) and poor outcome and might be used prognostically, together with other mortality risk factors; further prospective evaluation is needed.

Pneumocystis jirovecii Pneumonia

Pneumocystis jirovecii has gained attention during the last decade in the context of the AIDS epidemic and the increasing use of cytotoxic and immunosuppressive therapies. This article summarizes current knowledge on biology, pathophysiology, epidemiology, diagnosis, prevention, and treatment of pulmonary P jirovecii infection, with a particular focus on the evolving pathophysiology and epidemiology. Pneumocystis pneumonia still remains a severe opportunistic infection, associated with a high mortality rate.

Risk factors analysis for pneumocystis jiroveci pneumonia (PCP) in patients with haematological malignancies and pneumonia

A retrospective matched case-control investigation was conducted to assess risk factors suggesting Pneumocystis jiroveci pneumonia (PCP) when pneumonia occurs in adult patients with haematological malignancies. Cases and controls included were HIV-negative, presented with pneumonia and had benefited from a bronchoalveolar lavage (BAL). The presence of Pneumocystis jiroveci cysts was systematically investigated by cytochemical staining and/or immunofluorescence. Cases were patients with Pneumocystis jiroveci cysts isolated on BAL fluid (n = 31, mean age 51+/-14 y; range 20-73 y). Controls were patients without Pneumocystis jiroveci cysts (n = 62, mean age 54+/-13 y; range 25-75 y) and were matched to case patients by age and y of pneumonia diagnosis. Statistical analysis indicated that the following factors were associated with PCP: vincristine (p = 0.009, odds ratio (OR) =2.11, 95% confidence interval (CI): 1.19-3.72), a daily corticosteroid therapy for more than 1 month (p = 0.05) during the past y, and a lymphocyte count less than 0.5 x 10(9)/l on the d of pneumonia diagnosis (p = 0.04). Clinicians should be aware, in order to evoke this diagnosis when pneumonia occurs in patients with these risk factors. The goal of this exploratory study was to identify risk factors that could eventually be further investigated by a larger prospective multicentre study.

The absence of Hck, Fgr, and Lyn tyrosine kinases augments lung innate immune responses to Pneumocystis murina

Src family tyrosine kinases (SFKs) phosphorylate immunotyrosine activation motifs in the cytoplasmic tail of multiple immunoreceptors, leading to the initiation of cellular effector functions, such as phagocytosis, reactive oxygen species production, and cytokine production. SFKs also play important roles in regulating these responses through the activation of immunotyrosine inhibitory motif-containing inhibitory receptors. As myeloid cells preferentially express the SFKs Hck, Fgr, and Lyn, we questioned the role of these kinases in innate immune responses to Pneumocystis murina. Increased phosphorylation of Hck was readily detectable in alveolar macrophages after stimulation with P. murina. We further observed decreased phosphorylation of Lyn on its C-terminal inhibitory tyrosine in P. murina-stimulated alveolar macrophages, indicating that SFKs were activated in alveolar macrophages in response to P. murina. Mice deficient in Hck, Fgr, and Lyn exhibited augmented clearance 3 and 7 days after intratracheal administration of P. murina, which correlated with elevated levels of interleukin 1beta (IL-1beta), IL-6, CXCL1/KC, CCL2/monocyte chemoattractant protein 1, and granulocyte colony-stimulating factor in lung homogenates and a dramatic increase in macrophage and neutrophil recruitment. Augmented P. murina clearance was also observed in Lyn(-/-) mice 3 days postchallenge, although the level was less than that observed in Hck(-/-) Fgr(-/-) Lyn(-/-) mice. A correlate to augmented clearance of P. murina in Hck(-/-) Fgr(-/-) Lyn(-/-) mice was a greater ability of alveolar macrophages from these mice to kill P. murina in vitro, suggesting that SFKs regulate the alveolar macrophage effector function against P. murina. Mice deficient in paired immunoglobulin receptor B (PIR-B), an inhibitory receptor activated by SFKs, did not exhibit enhanced inflammatory responsiveness to or clearance of P. murina. Our results suggest that SFKs regulate innate lung responses to P. murina in a PIR-B-independent manner.

Pneumocystis jiroveci pneumonia in patients with non-Hodgkin's lymphoma receiving chemotherapy containing rituximab

Rituximab enhances treatment efficacy of B-lineage lymphoma by targeting CD20+ B-cells. Such target therapies may compromise the immune system and render patients susceptible to opportunistic infections. We report 2 cases of lymphoma complicated with Pneumocystis jiroveci (previously known as P. carinii) pneumonia (PCP) while being treated with rituximab-containing chemotherapy regimens. In both cases, PCP developed during the neutropenic period. With timely diagnosis and proper management, both were treated successfully. We searched the literature and found that such opportunistic infection occurred only infrequently in lymphoma patients, and it has not been reported in the large-scale clinical trials of rituximab. Such cases demonstrate the importance of taking PCP into diagnostic consideration in lymphoma patients receiving similar therapies.

Guidelines for diagnosing and treating pulmonary infiltrates in children with acute leukaemia: impact of timely decisions

AIM

Children with leukaemia are at increased risk of pulmonary complications, often with unspecific clinical data, delayed diagnosis and a high mortality rate. We evaluated the usefulness of diagnostic-therapeutic guidelines (DTG) in which specific times for decision making were incorporated.

METHODS

Clinical charts of children with acute leukaemia and suspicion of pulmonary involvement were reviewed. Patients were allocated to group I if their diagnostic and therapeutic decisions were in accordance with the DTG, and to group II if not.

RESULTS

Children from group I (n=32) and group II (n=28) did not differ with respect to age (9.3+/-0.5 years old, mean+/-SEM), gender, type, risk and stage of leukaemia, anaemia and neutropenia. Total length of hospital stay and hospitalization due to the pulmonary disease were shorter in group I than in group II (14.8+/-2.1 vs. 28.5+/-3.7 days, p=0.0016; and 10.8+/-1.0 vs. 18.4+/-1.8 days, p=0.0003, respectively). Two patients (6.3%) died due to the pulmonary pathology in group I, and nine (32.1%, p=0.016) in group II.

CONCLUSIONS

Diagnostic-therapeutic guidelines that incorporate timely decisions constitute a useful algorithm to reduce the length of hospital stay and mortality in children with acute leukaemia and pulmonary infiltrates. A prospective study is needed to validate these results.

Pneumocystis pneumonia in children receiving chemotherapy

Pneumocystis pneumonia (PCP) is a serious complication of chemotherapy-induced immunosuppression. Trimethoprim-sulfamethoxazole (TMP-SMZ) given twice daily, 3 days every week is considered the best form of prophylaxis for PCP. We evaluated PCP prophylaxis in all children up to 18 years of age undergoing cancer chemotherapy over a 2-year period. Four children were diagnosed with PCP over 24 months. Two of 12 children on intravenous pentamidine, 1 of 143 on TMP-SMZ and 1 of 36 on dapsone for PCP prophylaxis developed PCP. Intravenous pentamidine may not be as effective as previously considered and should be used with caution.

Critical care management and outcome of severe Pneumocystis pneumonia in patients with and without HIV infection

BACKGROUND

Little is known about the most severe forms of Pneumocystis jiroveci pneumonia (PCP) in HIV-negative as compared with HIV-positive patients. Improved knowledge about the differential characteristics and management modalities could guide treatment based on HIV status.

METHODS

We retrospectively compared 72 patients (73 cases, 46 HIV-positive) admitted for PCP from 1993 to 2006 in the intensive care unit (ICU) of a university hospital.

RESULTS

The yearly incidence of ICU admissions for PCP in HIV-negative patients increased from 1993 (0%) to 2006 (6.5%). At admission, all but one non-HIV patient were receiving corticosteroids. Twenty-three (85%) HIV-negative patients were receiving an additional immunosuppressive treatment. At admission, HIV-negative patients were significantly older than HIV-positive patients (64 [18 to 82] versus 37 [28 to 56] years old) and had a significantly higher Simplified Acute Physiology Score (SAPS) II (38 [13 to 90] versus 27 [11 to 112]) but had a similar PaO2/FiO2 (arterial partial pressure of oxygen/fraction of inspired oxygen) ratio (160 [61 to 322] versus 183 [38 to 380] mm Hg). Ventilatory support was required in a similar proportion of HIV-negative and HIV-positive cases (78% versus 61%), with a similar proportion of first-line non-invasive ventilation (NIV) (67% versus 54%). NIV failed in 71% of HIV-negative and in 13% of HIV-positive patients (p < 0.01). Mortality was significantly higher in HIV-negative than HIV-positive cases (48% versus 17%). The HIV-negative status (odds ratio 3.73, 95% confidence interval 1.10 to 12.60) and SAPS II (odds ratio 1.07, 95% confidence interval 1.02 to 1.12) were independently associated with mortality at multivariate analysis.

CONCLUSION

The yearly incidence of ICU admissions for PCP in HIV-negative patients in our unit increased from 1993 to 2006. The course of the disease and the outcome were worse in HIV-negative patients. NIV often failed in HIV-negative cases, suggesting that NIV must be watched closely in this population.