Epidemiology and long-term survival in HIV-infected patients with Pneumocystis jirovecii pneumonia in the HAART era: experience in a university hospital and review of the literature

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.

Pneumocystis jirovecii pneumonia in people living with HIV: a review

Pneumocystis jirovecii is a ubiquitous opportunistic fungus that can cause life-threatening pneumonia. People with HIV (PWH) who have low CD4 counts are one of the populations at the greatest risk of Pneumocystis jirovecii pneumonia (PCP). While guidelines have approached the diagnosis, prophylaxis, and management of PCP, the numerous studies of PCP in PWH are dominated by the 1980s and 1990s. As such, most studies have included younger male populations, despite PCP affecting both sexes and a broad age range. Many studies have been small and observational in nature, with an overall lack of randomized controlled trials. In many jurisdictions, and especially in low- and middle-income countries, the diagnosis can be challenging due to lack of access to advanced and/or invasive diagnostics. Worldwide, most patients will be treated with 21 days of high-dose trimethoprim sulfamethoxazole, although both the dose and the duration are primarily based on historical practice. Whether treatment with a lower dose is as effective and less toxic is gaining interest based on observational studies. Similarly, a 21-day tapering regimen of prednisone is used for patients with more severe disease, yet other doses, other steroids, or shorter durations of treatment with corticosteroids have not been evaluated. Now with the widespread availability of antiretroviral therapy, improved and less invasive PCP diagnostic techniques, and interest in novel treatment strategies, this review consolidates the scientific body of literature on the diagnosis and management of PCP in PWH, as well as identifies areas in need of more study and thoughtfully designed clinical trials.

Long-term Outcomes of Patients With HIV and Pneumocystis jirovecii Pneumonia in the Antiretroviral Therapy Era

Background

Pneumocystis jirovecii pneumonia (PCP) is one of the most frequent opportunistic infections in people with HIV (PWH). However, there are limited data on long-term outcomes of PCP in the antiretroviral therapy (ART) era.

Methods

We conducted a secondary analysis of 2 prospective studies on 307 PWH, 81 with prior PCP, with a median follow-up of 96 weeks. Laboratory data were measured at protocol-defined intervals. We reviewed clinically indicated chest computerized tomography imaging in 63 patients with prior PCP at a median of 58 weeks after PCP diagnosis and pulmonary function tests (PFTs) of patients with (n = 10) and without (n = 14) prior PCP at a median of 18 weeks after ART initiation.

Results

After 96 weeks of ART, PWH with prior PCP showed no significant differences in laboratory measurements, including CD4 count, when compared with those without prior PCP. Survival rates following ART initiation were similar. However, PWH with prior PCP had increased evidence of restrictive lung pathology and diffusion impairment in PFTs. Furthermore, on chest imaging, 13% of patients had bronchiectasis and 11% had subpleural cysts. Treatment with corticosteroids was associated with an increased incidence of cytomegalovirus disease (odds ratio, 2.62; P = .014).

Conclusions

PCP remains an important opportunistic infection in the ART era. While it did not negatively affect CD4 reconstitution, it could pose an increased risk for incident cytomegalovirus disease with corticosteroid treatment and may cause residual pulmonary sequelae. These findings suggest that PCP and its treatment may contribute to long-term morbidity in PWH, even in the ART era.

Impact of pneumocystosis on the Spanish health care system, 1997-2020: Profile of HIV and non-HIV immunocompromised patients

BACKGROUND

Pneumocystis jirovecii is an opportunistic fungus recognized for causing P. jirovecii pneumonia. The global prevalence is thought to be higher than 400,000 annual cases, although detailed information about epidemiological patterns is scarce.

METHODOLOGY

A retrospective longitudinal descriptive study was performed among patients with diagnosis of pneumocystosis according to Classification of Diseases 9th edition, Clinical Modification (code 136.3 for the cases from 1997 to 2015; and 10th edition code B59.0 for cases from 2016 to 2020 in Spanish public hospitals from 1 January 1997-31 December 2020.

RESULTS

A total of 25289 cases were diagnosed. The period incidence rate was 2.36 (95 % CI, 2.33-2.39) cases per 100,000 person-years. Infection was more frequent among men (72.2 %) than among women (27.8 %). Comorbidity was the main characteristic of this cohort. Up to 72.3 % of pneumocystis-infected patients (18293) had HIV coinfection. During the study period, there was a progressive decrease in the number of HIV coinfected cases as the group of patients without HIV infection increased, with the largest group in 2017. The lethality rate in the cohort was 16.7 %. The global cost was €229,234,805 and the average ( ± SD) cost per patient was €9065 ( ± 9315).

CONCLUSIONS

The epidemiology of pneumocystosis in Spain has changed in the last two decades. We noted in our study the possibility of a reemergence among non-HIV immunocompromised patients as patients with hematological and nonhematological neoplasia and other risk groups. The lethality of pneumocystosis continues to be high, and the underlying diseases are the main variable associated with lethality.

Risk of Pneumocystis jirovecii Pneumonia among Solid Organ Transplant Recipients: A Population-Based Study

Few studies have comprehensively investigated the occurrence of Pneumocystis jirovecii pneumonia (PJP) among solid organ transplant (SOT) recipients. This study investigated the risk of PJP after organ transplantation. Each patient who underwent SOT was propensity-score-matched with four non-SOT individuals in terms of sex, age, insured salary, urbanization of residence, comorbidities, and year of enrollment. When considering the 3-year follow-up, the patients who had undergone SOT were at higher risk of PJP, with the adjusted odds ratio (aOR) being 17.18 (95% confidence interval (CI): 8.80-33.53). Furthermore, SOT recipients were also at higher PJP risk than the patients without SOT at 6 months, 1 year, and 2 years, with the aOR being 22.64 (95% CI: 7.53-68.11), 26.19 (95% CI: 9.89-69.37), and 23.06 (95% CI: 10.23-51.97), respectively. Patients comorbid with HIV infection, hematological malignancies, or vasculitis were at higher risk (aOR = 59.08, 95% CI = 20.30-171.92), (aOR = 11.94, 95% CI = 5.36-26.61), and (aOR = 21.72, 95% CI = 2.41-195.81), respectively. The recipients of SOT were at higher risk of PJP, and PJP can develop at any stage after transplantation. SOT recipients comorbid with HIV, hematologic malignancies, or vasculitis were at higher PJP risk.

A comprehensive clinical guide for Pneumocystis jirovecii pneumonia: a missing therapeutic target in HIV-uninfected patients

INTRODUCTION

Pneumocystis jirovecii is an opportunistic, human-specific fungus that causes Pneumocystis pneumonia (PCP). PCP symptoms are nonspecific. A patient with P. jirovecii and another lung infection faces a diagnostic challenge. It may be difficult to determine which of these agents is responsible for the clinical symptoms, preventing effective treatment. Diagnostic and treatment efforts have been made more difficult by the rising frequency with which coronavirus 2019 (COVID-19) and PCP co-occur.

AREAS COVERED

Herein, we provide a comprehensive review of clinical and pharmacological recommendations along with a literature review of PCP in immunocompromised patients focusing on HIV-uninfected patients.

EXPERT OPINION

PCP may be masked by identifying co-existing pathogens that are not necessarily responsible for the observed infection. Patients with severe form COVID-19 should be examined for underlying immunodeficiency, and co-infections must be considered as co-infection with P. jirovecii may worsen COVID-19's severity and fatality. PCP should be investigated in patients with PCP risk factors who come with pneumonia and suggestive radiographic symptoms but have not previously received PCP prophylaxis. PCP prophylaxis should be explored in individuals with various conditions that impair the immune system, depending on their PCP risk.

Trends in the Epidemiology and Outcomes of Pneumocystis Pneumonia among Human Immunodeficiency Virus (HIV) Hospitalizations

Introduction: Pneumocystis Pneumonia (PCP) is a common opportunistic infection among people living with the human immunodeficiency virus (HIV). This study’s objective was to assess temporal trends in PCP epidemiology among hospitalized patients with HIV/AIDS in the US and to compare data for hospitalizations with HIV with PCP to those without PCP. Methods: The national inpatient sample (NIS) data were analyzed from 2002−2014. The discharge coding identified hospitalized patients with HIV or AIDS and with or without PCP. Results: We identified 3,011,725 hospitalizations with HIV/AIDS during the study period; PCP was present in 5% of the patients with a diagnosis of HIV. The rates of PCP progressively declined from 6.7% in 2002 to 3.5 % in 2014 (p < 0.001). Overall mortality in patients with HIV was 3.3% and was significantly higher in those with PCP than without PCP (9.9% vs. 2.9%; p < 0.001). After adjusting for demographics and other comorbidities, PCP had higher odds of hospital mortality 3.082 (OR 3.082; 95% CI, 3.007 to 3.159; p < 0.001). Conclusion: From 2002 to 2014, the rate of PCP in HIV patients has decreased significantly in the United States but is associated with substantially higher mortality.

Performance of a Real Time PCR for Pneumocystis jirovecii Identification in Induced Sputum of AIDS Patients: Differentiation between Pneumonia and Colonization

Pneumocystis jirovecii pneumonia (PcP) remains an important cause of morbimortality worldwide and a diagnostic challenge. Conventional methods have low accuracy, hardly discriminating colonization from infection, while some new high-cost or broncho-alveolar lavage-based methods have limited usefulness in developing countries. Quantitative PCR (qPCR) tests may overcome these limitations due to their high accuracy, possibility of automation, and decreasing cost. We evaluated an in-house qPCR targeting the fungus mtSSU gene using induced sputum. Sensitivity of the assay (ten target gene copies/assay) was determined using recombinant plasmids. We prospectively studied 86 AIDS patients with subacute respiratory symptoms in whom PcP was suspected. qPCR results were determined as quantification cycles (Cq) and compared with a qualitative PCR performed in the same IS, serum 1,3-β-D-Glucan assay, and a clinical/laboratory/radiology index for PcP. The qPCR clustered the patients in three groups: 32 with Cq ≤ 31 (qPCR+), 45 with Cq ≥ 33 (qPCR-), and nine with Cq between 31-33 (intermediary), which, combined with the other three analyses, enabled us to classify the groups as having PcP, not P. jirovecii-infected, and P. jirovecii-colonized, respectively. This molecular assay may contribute to improve PcP management, avoiding unnecessary treatments, and our knowledge of the natural history of this infection.

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: a review with a focus on prevention and treatment

Introduction: Pneumocystis jirovecii (PJ) is an opportunistic fungal pathogen that can cause severe pneumonia in immunocompromised hosts. Risk factors for Pneumocystis jirovecii pneumonia (PJP) include HIV, organ transplant, malignancy, certain inflammatory or rheumatologic conditions, and associated therapies and conditions that result in cell-mediated immune deficiency. Clinical signs of PJP are nonspecific and definitive diagnosis requires direct detection of the organism in lower respiratory secretions or tissue. First-line therapy for prophylaxis and treatment remains trimethoprim-sulfamethoxazole (TMP-SMX), though intolerance or allergy, and rarely treatment failure, may necessitate alternate therapeutics, such as dapsone, pentamidine, atovaquone, clindamycin, primaquine and most recently, echinocandins as adjunctive therapy. In people living with HIV (PLWH), adjunctive corticosteroid use in treatment has shown a mortality benefit.Areas covered: This review article covers the epidemiology, pathophysiology, diagnosis, microbiology, prophylaxis indications, prophylactic therapies, and treatments.Expert opinion: TMP-SMX has been first-line therapy for treating and preventing pneumocystis for decades. However, its adverse effects are not uncommon, particularly during treatment. Second-line therapies may be better tolerated, but often sacrifice efficacy. Echinocandins show some promise for new combination therapies; however, further studies are needed to define optimal antimicrobial therapy for PJP as well as the role of corticosteroids in those without HIV.

Timing of antiretroviral therapy for HIV-infected patients with moderate to severe Pneumocystis pneumonia: study protocol for a multi-centre prospective randomised controlled trial

Background

Pneumocystis pneumonia (PCP) is a common acquired immune deficiency syndrome (AIDS)-related opportunistic infection. Recent reports estimate that more than 400,000 patients with human immunodeficiency virus (HIV) develop PCP each year globally. However, the timing of antiretroviral therapy (ART) initiation for HIV-infected patients with PCP is still controversial, and the benefits and risks of early initiation of ART are not completely clear. We thus designed this study in order to determine the optimal timing for ART initiation for HIV-positive patients with moderate to severe PCP.

Methods

This study will be an open-label, multi-centre, prospective randomised controlled trial. A total of 200 subjects will be randomly assigned to an early ART initiation group (≤14 days after PCP diagnosis) and a deferred ART initiation group (>14 days after PCP diagnosis) at a 1:1 ratio. All subjects will be followed up for 48 weeks after starting ART. The primary endpoint is incidence of disease progression (including new or relapsing opportunistic infections and death) at week 48. The secondary endpoints are the changes in CD4 counts from baseline at weeks 12, 24 and 48; the degree of virological suppression (HIV RNA < 50 copies/mL) at weeks 24 and 48; the rate of development of PCP-associated immune reconstitution inflammatory syndrome; and adverse events over 48 weeks.

Discussion

We hope that the results of this study will reveal the optimal timing for initiation of ART in HIV-infected patients with moderate to severe PCP.

Trial registration

This trial was registered as one of the 12 trials under the name of a general project at chictr.org.cn on February 1, 2019. The registration number of the general project is ChiCTR1900021195.

CD4+ T cell lymphopenia predicts mortality from Pneumocystis pneumonia in kidney transplant patients

BACKGROUND

Pneumocystis jirovecii pneumonia (PcP) remains a life-threatening opportunistic infection after solid organ transplantation, even in the era of Pneumocystis prophylaxis. The association between risk of developing PcP and low CD4⁺ T cell counts has been well established. However, it is unknown whether lymphopenia in the context of post-renal transplant PcP increases the risk of mortality.

METHODS

We carried out a retrospective analysis of a cohort of kidney transplant patients with PcP (n = 49) to determine the risk factors for mortality associated with PcP. We correlated clinical and demographic data with the outcome of the disease. For CD4⁺ T cell counts, we used the Wilcoxon rank sum test for in-hospital mortality and a Cox proportional-hazards regression model for 60-day mortality.

RESULTS

In univariate analyses, high CRP, high neutrophils, CD4⁺ T cell lymphopenia, mechanical ventilation, and high acute kidney injury network stage were associated with in-hospital mortality following presentation with PcP. In a receiver-operator characteristic (ROC) analysis, an optimum cutoff of ≤200 CD4⁺ T cells/µL predicted in-hospital mortality, CD4⁺ T cell lymphopenia remained a risk factor in a Cox regression model.

CONCLUSIONS

Low CD4⁺ T cell count in kidney transplant recipients is a biomarker for disease severity and a risk factor for in-hospital mortality following presentation with PcP.

Changing Trends in the Epidemiology and Risk Factors of Pneumocystis Pneumonia in Spain

Objective: The information about the epidemiology of Pneumocystis pneumonia (PcP) in Europe is scarce, and in Spain there are only data nationwide on patients with HIV infection. This study has been carried out with the aim of knowing in our country the current epidemiological spectrum and the risk factors of PcP.

Methods: Observational, descriptive transversal study that included all patients admitted in Spain with diagnosis upon discharge of PcP registered in the National Health System's Hospital Discharge Records Database of Spain, between 2008 and 2012.

Results: Four thousand five hundred and fifty four cases of PcP were reported, 1,204 (26.4%) in HIV-negative patients. During the study period, mean annual incidence (cases per million) was 19.4, remaining globally stable, increasing from 4.4 to 6.3 in HIV-negative patients and decreasing from 15.5 to 13.4 among HIV-infected patients. Risk factors were identified in 85.5% of HIV-negative cases, the most frequent being hematological neoplams (29%), chronic lung diseases (15.9%), and non-hematological cancers (14.9%). Mean mortality and hospitalization cost were high (25.5% and 12,000 euros, respectively).

Conclusions: The results of this first nationwide study in Spain allow a change in the misconception that, after the AIDS epidemic, PcP is an infrequent disease, showing that today it is an emerging problem in patients without HIV infection. These findings underlines the need for increased efforts toward a better characterization of risk groups to improve prophylactic strategies and reduce the burden of disease.

Pneumocystis pneumonia in the twenty-first century: HIV-infected versus HIV-uninfected patients

Introduction: Pneumocystis pneumonia (PcP) has classically been described as a serious complication in patients infected with the human immunodeficiency virus (HIV). However, the emerging number of conditions associated with immunosuppression has led to its appearance in other patient populations. Areas covered: This article reviews the most recent publications on PcP in the HIV-infected and HIV-uninfected population, focusing on epidemiology, diagnostic, therapy and prevention. The data discussed here were mainly obtained from a non-systematic review using Medline and references from relevant articles including randomized clinical trials, meta-analyses, observational studies and clinical reviews. Expert opinion: The growing incidence of Pneumocystis infection in the HIV-uninfected population suggests the need for new global epidemiological studies in order to identify the true scale of the disease in this population. These data would allow us to improve diagnosis, therapeutic strategies, and clinical management. It is very important that both patients and physicians realize that HIV-uninfected patients are at risk of PcP and that rapid diagnosis and early initiation of treatment are associated with better prognosis. Currently, in-hospital mortality rates are very high: 15% for HIV-infected patients and 50% in some HIV-uninfected patients. Therefore, adequate preventive measures should be implemented to avoid the high mortality rates seen in recent decades.

Pneumocystis jiroveci Pneumonia in HIV-Positive and HIV-Negative Patients: A Single-Center Retrospective Study

BACKGROUND

To describe the clinical presentations, treatment regimen, and outcomes of Pneumocystis jiroveci pneumonia (PJP) among immunocompromised patients at King Faisal Specialist Hospital and Research Center in Saudi Arabia.

MATERIALS AND METHODS

In this retrospective cohort study, patients with a laboratory-confirmed diagnosis of PJP were included.

RESULTS

During the study, 42 patients with confirmed PJP were identified. Twenty (48%) patients were HIV-infected, while 22 (52%) were HIV negative. The median T-cell count (CD ₄ ) was below 50 cells/mL in HIV patients with PJP at the time of HIV and PJP diagnoses. Graft rejection, cytomegalovirus (CMV) reactivation, and lymphopenia were associated with the development of PJP in transplant recipients; and high-dose steroids for non-transplant patients. The all-cause mortality at 90 days was lower in individuals with HIV-related PJP, compared to those with other predisposing conditions (10% and 32%, respectively; P=0.085). No specific risk factors were independently associated with the increased risk of mortality.

CONCLUSION

PJP remains an important cause of morbidity and mortality in immunocompromised patients, with a higher mortality rate reported in non-HIV patients.

Immune reconstitution inflammatory syndrome in HIV-infected patients with Pneumocystis jirovecii pneumonia

INTRODUCTION

The incidence of immune reconstitution inflammatory syndrome (IRIS) in HIV-infected patients after an episode of Pneumocystis jirovecii pneumonia (PJP) seems to be lower than with other opportunistic infections. We conducted an observational study in order to determine the incidence, clinical characteristics and outcome of patients diagnosed with PJP-related IRIS.

METHODS

We conducted an observational study of HIV patients diagnosed with PJP-related IRIS from January 2000 to November 2015. We analyzed epidemiological and clinical characteristics as well as laboratory findings. We also carried out a systematic review of published cases.

RESULTS

Six cases of IRIS out of 123 (4.9%) HIV-infected patients with PJP who started ART were diagnosed. All six cases were men with a median age of 34 (IQR: 8) years. The six patients developed paradoxical IRIS. Subjects younger than 40 years old (p=0.084) and with an HIV-RNA viral load >100000 copies/ml (p=0.081) at diagnosis showed a tendency to develop IRIS. Thirty-seven published cases of PJP-related IRIS were identified. Although 51% of cases involved respiratory failure, no deaths were reported.

CONCLUSIONS

PJP-related IRIS is rare condition compared to other opportunistic infections. It can lead to a severe respiratory failure in a significant proportion of cases, although no deaths have been reported.

Fungal infections in HIV/AIDS

Fungi are major contributors to the opportunistic infections that affect patients with HIV/AIDS. Systemic infections are mainly with Pneumocystis jirovecii (pneumocystosis), Cryptococcus neoformans (cryptococcosis), Histoplasma capsulatum (histoplasmosis), and Talaromyces (Penicillium) marneffei (talaromycosis). The incidence of systemic fungal infections has decreased in people with HIV in high-income countries because of the widespread availability of antiretroviral drugs and early testing for HIV. However, in many areas with high HIV prevalence, patients present to care with advanced HIV infection and with a low CD4 cell count or re-present with persistent low CD4 cell counts because of poor adherence, resistance to antiretroviral drugs, or both. Affordable, rapid point-of-care diagnostic tests (as have been developed for cryptococcosis) are urgently needed for pneumocystosis, talaromycosis, and histoplasmosis. Additionally, antifungal drugs, including amphotericin B, liposomal amphotericin B, and flucytosine, need to be much more widely available. Such measures, together with continued international efforts in education and training in the management of fungal disease, have the potential to improve patient outcomes substantially.

When to Consider the Possibility of a Fungal Infection: An Overview of Clinical Diagnosis and Laboratory Approaches

Fungal infections are an important and increasingly prevalent cause of disease in certain patient populations. These infections can occur both in immune-compromised and immune-competent individuals. Because the number of patients who are immunocompromised is steadily growing, it is vital for clinicians to consider fungal disease in the differential diagnosis of these patients. This article reviews the epidemiology and approach to diagnosis of a variety of fungal infections.

Infectious disease ward admission positively influences P. jiroveci pneumonia (PjP) outcome: A retrospective analysis of 116 HIV-positive and HIV-negative immunocompromised patients

P. jiroveci (Pj) causes a potentially fatal pneumonia in immunocompromised patients and the factors associated with a bad outcome are poorly understood. A retrospective analysis on Pj pneumonia (PjP) cases occurring in Tor Vergata University Hospital, Italy, during the period 2011–2015. The patients’ demographic, clinical and radiological characteristics and the Pj genotypes were considered. The study population included 116 patients, 37.9% of whom had haematological malignancy or underwent haematological stem cell transplantation (HSCT), 22.4% had HIV infection, 16.4% had chronic lung diseases (CLD), 7.8% had a solid cancer, and 3.4% underwent a solid organ transplant (SOT). The remaining 12.1% had a miscellaneous other condition. At univariate analysis, being older than 60 years was significantly correlated with a severe PjP (OR [95%CI] 2.52 [0.10–5.76]; p = 0.031) and death (OR [95%CI] 2.44 [1.05–5.70]; p = 0.036), while a previous trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were significantly associated with a less severe pneumonia (OR[95%CI] 0.35 [0.15–0.84], p = 0.023); moreover, death due to PjP was significantly more frequent in patients with CLD (OR[95%CI] 3.26 [1.17–9.05]; p = 0.019) while, admission to the Infectious Diseases Unit was significantly associated with fewer deaths (OR[95%CI] 0.10 [0.03–0.36], p = 0.002). At multivariate analysis, a better PjP outcome was observed in patients taking TMP/SMX prophylaxis and that were admitted to the Infectious Diseases Unit (OR[95%CI] 0.27 [0.07–1.03], p = 0.055, OR[95%CI] 0.16 [0.05–0.55]; p = 0.004, respectively).

In conclusion, in our study population, TMP/SMX prophylaxis and infectious disease specialist approach were variables correlated with a better PjP outcome.

Immune Reconstitution Inflammatory Syndrome (IRIS): What pathologists should know

Antiretroviral therapy has significantly improved the quality and length of life for those patients able to access effective and sustained treatment. The resulting restoration of the immune response is associated with a change in the clinical presentation of opportunistic infections, and the histologic reaction to pathogens. A complex combination of alterations in host response across the stages of HIV infection has been documented over the past 3 decades. The defects are seen in both acute and chronic phases of inflammation and involve innate and adaptive immunity. In advanced stages of HIV infection, the marked disruption of lymphoid tissue and loss of follicular dendritic cells limits the host's ability to process antigen and mount specific responses to pathogens. There are qualitative and quantitative defects in CD4 T cells due to HIV infection. The resulting indirect effects include loss of cytokine production, dysregulation of B-cell function, loss of cellular mediated immunity and "holes" in the immunologic repertoire that may not be restored with the use of antiretroviral therapy. Immune reconstitution allows the host to respond to and control infection, but a significant number of patients will have atypical inflammatory syndromes during the recovery period. We briefly discuss the impact of HIV infection on the immune system and give an overview of the spectrum of conditions attributed to the Immune Reconstitution Inflammatory syndrome (IRIS).

[Pneumocystosis during HIV infection]

Pneumocystosis is an opportunistic disease caused by invasion of unicellular fungus Pneumocystic jirovecii which is responsible for febrile pneumonia among patients with cellular immunodeficiency especially those HIV infected. Despite the decreasing of its incidence due to the introduction of antiretroviral therapy, as well as anti-Pneumocystis prophylaxis among these patients, Pneumocystis pneumonia remains the first AIDS-defining event and a leading cause of mortality among HIV-infected patients. The usual radiological presentation is that of diffuse interstitial pneumonia. The diagnosis is confirmed by the detection of trophozoides and/or cysts P. jirovecii in bronchoalveolar lavage (BAL) samples using several staining techniques. The use of polymerase chain reaction in the BAL samples in conjunction with standard immunofluorescent or colorimetric tests have allowed for more has allowed for more rapid and accurate diagnosis. The standard regimen of treatment is the association of trimethoprim-sulfamethoxazole which has been utilized as an effective treatment with a favourable recovery. Early HIV diagnosis and antiretroviral therapy should reduce the incidence of this dreaded disease.

Detection of Pneumocystis jirovecii by Quantitative PCR To Differentiate Colonization and Pneumonia in Immunocompromised HIV-Positive and HIV-Negative Patients

Pneumocystis jirovecii pneumonia (PCP) is an acute and life-threatening lung disease caused by the fungus Pneumocystis jirovecii The presentation of PCP in HIV-positive patients is well-known and consists of a triad of dyspnea, fever, and cough, whereas the presentation of PCP in HIV-negative patients is atypical and consists of a sudden outbreak, O2 desaturation, and a rapid lethal outcome without therapy. Despite the availability of direct and indirect identification methods, the diagnosis of PCP remains difficult. The cycle threshold (CT) values obtained by quantitative PCR (qPCR) allow estimation of the fungal burden. The more elevated that the fungal burden is, the higher the probability that the diagnosis is pneumonia. The purposes of the present study were to evaluate the CT values to differentiate colonization and pneumonia in a population of immunocompromised patients overall and patients stratified on the basis of their HIV infection status. Testing of bronchoalveolar lavage (BAL) fluid samples from the whole population of qPCR-positive patients showed a mean CT value for patients with PCP of 28 (95% confidence interval [CI], 26 to 30) and a mean CT value for colonized patients of 35 (95% CI, 34 to 36) (P < 10(-3)). For the subgroup of HIV-positive patients, we demonstrated that a CT value below 27 excluded colonization and a CT value above 30 excluded PCP with a specificity of 100% and a sensitivity of 80%, respectively. In the subgroup of HIV-negative patients, we demonstrated that a CT value below 31 excluded colonization and a CT value above 35 excluded PCP with a specificity of 80% and a sensitivity of 80%, respectively. Thus, qPCR of BAL fluid samples is an important tool for the differentiation of colonization and pneumonia in P. jirovecii-infected immunocompromised patients and patients stratified on the basis of HIV infection status with different CT values.