Atovaquone compared with dapsone for the prevention of Pneumocystis carinii pneumonia in patients with HIV infection who cannot tolerate trimethoprim, sulfonamides, or both. Community Program for Clinical Research on AIDS and the AIDS Clinical Trials Group

ISCCM Position Statement on the Management of Invasive Fungal Infections in the Intensive Care Unit

Rationale

Invasive fungal infections (IFI) in the intensive care unit (ICU) are an emerging problem owing to the use of broad-spectrum antibiotics, immunosuppressive agents, and frequency of indwelling catheters. Timely diagnosis which is imperative to improve outcomes can be challenging. This position statement is aimed at understanding risk factors, providing a rational diagnostic approach, and guiding clinicians to optimize antifungal therapy.

Objectives

To update evidence on epidemiology, risk factors, diagnostic approach, antifungal initiation strategy, therapeutic interventions including site-specific infections and role of therapeutic drug monitoring in IFI in ICU and focus on some practice points relevant to these domains.

Methodology

A committee comprising critical care specialists across the country was formed and specific aspects of fungal infections and antifungal treatment were assigned to each member. They extensively reviewed the literature including the electronic databases and the international guidelines and cross-references. The information was shared and discussed over several meetings and position statements were framed to ensure their reliability and relevance in critical practice. The draft document was prepared after obtaining inputs and consensus from all the members and was reviewed by an expert in this field.

Results

The existing evidence on the management of IFI was updated and practice points were prepared under each subheading to enable critical care practitioners to streamline diagnosis and treatment strategies for patients in the ICU with additional detail on site-specific infections therapeutic drug monitoring.

Conclusion

This position statement attempts to address the management of IFI in immunocompetent and non-neutropenic ICU patients. The practice points should guide in optimization of the management of critically ill patients with suspected or proven fungal infections.

How to cite this article

Bhattacharya PK, Chakrabarti A, Sinha S, Pande R, Gupta S, Kumar AAK, et al. ISCCM Position Statement on the Management of Invasive Fungal Infections in the Intensive Care Unit. Indian J Crit Care Med 2024;28(S2):S20-S41.

Comparative efficacy and safety of Pneumocystis jirovecii pneumonia prophylaxis regimens for people living with HIV: a systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Pneumocystis jirovecii pneumonia (PCP) is a common opportunistic infection among people living with HIV (PWH), particularly among new and untreated cases. Several regimens are available for the prophylaxis of PCP, including trimethoprim-sulfamethoxazole (TMP-SMX), dapsone-based regimens (DBRs), aerosolized pentamidine (AP), and atovaquone.

OBJECTIVES

To compare the efficacy and safety of PCP prophylaxis regimens in PWH by network meta-analysis.

METHODS

DATA SOURCES: Embase, MEDLINE, and CENTRAL from inception to June 21, 2023.

STUDY ELIGIBILITY CRITERIA

Comparative randomized controlled trials (RCTs).

PARTICIPANTS

PWH.

INTERVENTIONS

Regimens for PCP prophylaxis either compared head-to-head or versus no treatment/placebo.

ASSESSMENT OF RISK OF BIAS

Cochrane risk-of-bias tool for RCTs 2.

METHODS OF DATA SYNTHESIS

Title or abstract and full-text screening and data extraction were performed in duplicate by two independent reviewers. Data on PCP incidence, all-cause mortality, and discontinuation due to toxicity were pooled and ranked by network meta-analysis. Subgroup analyses of primary versus secondary prophylaxis, by year, and by dosage were performed.

RESULTS

A total of 26 RCTs, comprising 55 treatment arms involving 7516 PWH were included. For the prevention of PCP, TMP-SMX was ranked the most favourable agent and was superior to DBRs (risk ratio [RR] = 0.54; 95% CI, 0.36-0.83) and AP (RR = 0.53; 95% CI, 0.36-0.77). TMP-SMX was also the only agent with a mortality benefit compared with no treatment/placebo (RR = 0.79; 95% CI, 0.64-0.98). However, TMP-SMX was also ranked as the most toxic agent with a greater risk of discontinuation than DBRs (RR = 1.25; 95% CI, 1.01-1.54) and AP (7.20; 95% CI, 5.37-9.66). No significant differences in PCP prevention or mortality were detected among the other regimens. The findings remained consistent within subgroups.

CONCLUSIONS

TMP-SMX is the most effective agent for PCP prophylaxis in PWH and the only agent to confer a mortality benefit; consequently, it should continue to be recommended as the first-line agent. Further studies are necessary to determine the optimal dosing of TMP-SMX to maximize efficacy and minimize toxicity.

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.

EULAR recommendations for the management of ANCA-associated vasculitis: 2022 update

BACKGROUND

Since the publication of the EULAR recommendations for the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in 2016, several randomised clinical trials have been published that have the potential to change clinical care and support the need for an update.

METHODS

Using EULAR standardised operating procedures, the EULAR task force undertook a systematic literature review and sought opinion from 20 experts from 16 countries. We modified existing recommendations and created new recommendations.

RESULTS

Four overarching principles and 17 recommendations were formulated. We recommend biopsies and ANCA testing to assist in establishing a diagnosis of AAV. For remission induction in life-threatening or organ-threatening AAV, we recommend a combination of high-dose glucocorticoids (GCs) in combination with either rituximab or cyclophosphamide. We recommend tapering of the GC dose to a target of 5 mg prednisolone equivalent/day within 4-5 months. Avacopan may be considered as part of a strategy to reduce exposure to GC in granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA). Plasma exchange may be considered in patients with rapidly progressive glomerulonephritis. For remission maintenance of GPA/MPA, we recommend rituximab. In patients with relapsing or refractory eosinophilic GPA, we recommend the use of mepolizumab. Azathioprine and methotrexate are alternatives to biologics for remission maintenance in AAV.

CONCLUSIONS

In the light of recent advancements, these recommendations provide updated guidance on AAV management. As substantial data gaps still exist, informed decision-making between physicians and patients remains of key relevance.

Repurposing Atovaquone as a Therapeutic against Acute Myeloid Leukemia (AML): Combination with Conventional Chemotherapy Is Feasible and Well Tolerated

Survival of pediatric AML remains poor despite maximized myelosuppressive therapy. The pneumocystis jiroveci pneumonia (PJP)-treating medication atovaquone (AQ) suppresses oxidative phosphorylation (OXPHOS) and reduces AML burden in patient-derived xenograft (PDX) mouse models, making it an ideal concomitant AML therapy. Poor palatability and limited product formulations have historically limited routine use of AQ in pediatric AML patients. Patients with de novo AML were enrolled at two hospitals. Daily AQ at established PJP dosing was combined with standard AML therapy, based on the Medical Research Council backbone. AQ compliance, adverse events (AEs), ease of administration score (scale: 1 (very difficult)-5 (very easy)) and blood/marrow pharmacokinetics (PK) were collected during Induction 1. Correlative studies assessed AQ-induced apoptosis and effects on OXPHOS. PDX models were treated with AQ. A total of 26 patients enrolled (ages 7.2 months-19.7 years, median 12 years); 24 were evaluable. A total of 14 (58%) and 19 (79%) evaluable patients achieved plasma concentrations above the known anti-leukemia concentration (>10 µM) by day 11 and at the end of Induction, respectively. Seven (29%) patients achieved adequate concentrations for PJP prophylaxis (>40 µM). Mean ease of administration score was 3.8. Correlative studies with AQ in patient samples demonstrated robust apoptosis, OXPHOS suppression, and prolonged survival in PDX models. Combining AQ with chemotherapy for AML appears feasible and safe in pediatric patients during Induction 1 and shows single-agent anti-leukemic effects in PDX models. AQ appears to be an ideal concomitant AML therapeutic but may require intra-patient dose adjustment to achieve concentrations sufficient for PJP prophylaxis.

Management of drug-induced neutropenia, thrombocytopenia, and anaemia after solid organ transplantation: A comprehensive review

WHAT IS KNOWN AND OBJECTIVE

Advances in the development of more effective immunosuppressive drugs have increased graft survival and drug induced adverse effects. Haematological complications including neutropenia, thrombocytopenia, and anaemia are common side effects that affect the grafts' and patients' outcomes. Several studies have stated the important role of various medications in haematological complications after transplantation. They have reported the incidence and different mechanisms of drug induced cytopenia, as well as an overview of possible treatment modalities. However, there is no comprehensive protocol for the management of these complications following transplantation. This narrative review was performed to develop a comprehensive practical approach for management of drug induced haematological complications following solid organ transplantation.

METHOD

PubMed, Embase, Cochrane library, Web of Science, and Google scholar databases were searched without time limitations until March, 2021. In addition, some valid drug information data bases (Uptodate and Micromedex) were searched for detailed information until October, 2021.

RESULTS AND DISCUSSION

Several immunosuppressive and antimicrobial medications may induce neutropenia, thrombocytopenia or anaemia following transplantation. Most of these agents cause dose-related cytopenia, which resolves with dose reduction or drug withdrawal. However, any change in medications may result in negative consequences such as severe infections, bleeding, cardiovascular complications, acute allograft rejection, and graft or patient loss. Thus, cautious evaluation of the patient's condition and the pharmacological properties of the culprit medication are required.

WHAT IS NEW AND CONCLUSION

Three algorithms are presented to guide healthcare providers in the stepwise management of drug-induced neutropenia, thrombocytopenia, and anaemia after solid organ transplantation.

Estimation of treatment and prognostic factors of pneumocystis pneumonia in patients with connective tissue diseases

Objectives

To investigate short-term prognosis and prognostic factors for connective tissue disease-associated pneumocystis pneumonia (CTD-PCP) using the Japanese nationwide diagnosis procedure combination (DPC) inpatient database.

Methods

The present retrospective cohort study from April 2014 to March 2016 included data of patients with CTD-PCP extracted from the DPC database using the 10^th revision of International Classification of Diseases and Injuries codes.

Results

In 15 901 766 cases registered from 1329 hospitals, 333 of 67 890 patients who were admitted with PCP were diagnosed with CTD-PCP and included in the study. The median age was 71.0 years, and 214 (64.3%), 80 (24.0%), and 29 (8.7%) patients received sulfamethoxazole/trimethoprim (ST) monotherapy and pentamidine-containing and atovaquone-containing therapy, respectively. There were 114 (34.2%) in-hospital deaths, and the 30-day and 60-day in-hospital survival rates after PCP treatment initiation were 66.0% and 53.7%, respectively. Older age (HR 1.06, 95% CI 1.03 to 1.08) and concomitant interstitial lung disease (ILD) (HR 1.65, 95% CI 1.12 to 2.42) were poor prognostic factors. Patients who completed PCP treatment with ST monotherapy had a significantly higher survival rate than those treated with those not treated with ST monotherapy (p=0.015; log-rank test). Pentamidine versus atovaquone as second-line therapy was significantly higher with atovaquone (p=0.012; log-rank test).

Conclusion

Older age and concomitant ILD were poor prognostic factors for CTD-PCP. ST was a reasonable first-line therapy in patients with CTD-PCP, and patients with inadequate response to ST treated with atovaquone tended to have a better prognosis than those treated with pentamidine.

Primary prophylaxis of bacterial infections and Pneumocystis jirovecii pneumonia in patients with hematologic malignancies and solid tumors: 2020 updated guidelines of the Infectious Diseases Working Party of the German Society of Hematology and Medical Oncology (AGIHO/DGHO)

Hematologic and oncologic patients with chemo- or immunotherapy-related immunosuppression are at substantial risk for bacterial infections and Pneumocystis jirovecii pneumonia (PcP). As bacterial resistances are increasing worldwide and new research reshapes our understanding of the interactions between the human host and bacterial commensals, administration of antibacterial prophylaxis has become a matter of discussion. This guideline constitutes an update of the 2013 published guideline of the Infectious Diseases Working Party (AGIHO) of the German Society for Hematology and Medical Oncology (DGHO). It gives an overview about current strategies for antibacterial prophylaxis in cancer patients while taking into account the impact of antibacterial prophylaxis on the human microbiome and resistance development. Current literature published from January 2012 to August 2020 was searched and evidence-based recommendations were developed by an expert panel. All recommendations were discussed and approved in a consensus conference of the AGIHO prior to publication. As a result, we present a comprehensive update and extension of our guideline for antibacterial and PcP prophylaxis in cancer patients.

Dapsone-induced methemoglobinemia in pediatrics post-renal transplant

Dapsone has been utilized for the prevention of Pneumocystis jirovecii pneumonia in immunosuppressed patients including pediatric kidney transplant recipients, in whom trimethoprim-sulfamethoxazole (TMP-SMX) is contraindicated. Dapsone adverse effects include methemoglobinemia, but there are no reports of the burden and impact of methemoglobinemia in pediatric kidney recipients that are taking dapsone for PJP prophylaxis. We conducted a retrospective chart review of all pediatric kidney recipients who had received dapsone at any time posttransplant. The indication, duration, and adverse effects of dapsone therapy were assessed. In addition, methemoglobin levels were assessed, and summary statistics performed. Data demonstrated that more than half of the patients on dapsone were not screened for methemoglobinemia. Of those screened, there was a significantly higher acquired-methemoglobinemia (77%) than previously reported in the literature. We also demonstrate significantly more anemia in patients on dapsone. Methemoglobinemia did not affect patient or graft survival and resolved with cessation of dapsone. We conclude that pediatric kidney recipients often develop methemoglobinemia and / or anemia on dapsone. We recommend if pediatric transplant recipients are prescribed dapsone, routine testing for methemoglobinemia and anemia should be done.

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.

Risk factors associated with increased discontinuation rate of trimethoprim-sulfamethoxazole used as a primary prophylaxis for Pneumocystis pneumonia: A retrospective cohort study

BACKGROUND

The use of trimethoprim-sulfamethoxazole (TMP-SMX) for Pneumocystis pneumonia (PcP) prophylaxis is often discontinued owing to adverse drug reactions. Half-dosage of TMP-SMX (40/200 mg daily) is considered more tolerable than the conventional dosage (80/400 mg daily). However, patient background characteristics that are associated with the discontinuation of TMP-SMX prophylaxis and suitable for reduced dosage remain unclear. In this study, we aimed to identify the risk factors for the discontinuation of and efficacy of different doses of TMP-SMX prophylaxis in patients with creatinine clearance higher than 30 mL/min.

METHODS

We retrospectively evaluated 318 immunocompromised non-human immunodeficiency virus (HIV)-infected patients (194 men and 124 women; median age, 68.5 [interquartile range, 59-75] years) who underwent TMP-SMX therapy as a primary PcP prophylaxis between July 2014 and August 2019. The patients were segregated into two groups on the basis of dosage: single-strength (SS; n = 244) and half-strength (HS; n = 74) groups. We evaluated PcP occurrence, TMP-SMX discontinuation rate, and discontinuation-related risk factors in these groups.

RESULTS

PcP did not occur in either group. The univariate and multivariate Cox proportional hazards models revealed that the SS dosage and renal function (e.g. serum creatinine and creatinine clearance) were independently associated with prophylaxis discontinuation. At 24 weeks, the HS group presented significantly lower discontinuation rates than the SS group (P = 0.019, log-rank test). In the SS group, patients with mild renal impairment (e.g. serum creatinine ≥0.78 mg/dL or creatinine clearance ≤64.26 mL/min) presented significantly higher TMP-SMX discontinuation rates than those without such an impairment (P < 0.05, log-rank test with Bonferroni correction). This difference was not significant in the HS group.

CONCLUSION

Mild renal impairment might increase the risk of discontinuation of conventional TMP-SMX prophylaxis. In patients with a mild renal impairment, the HS dosage may improve tolerability while maintaining prophylactic efficacy.

A Novel Encochleated Formulation Improves Atovaquone Activity in a Murine Model of Pneumocystis Pneumonia

Although atovaquone is effective in treating and preventing Pneumocystis pneumonia (PCP), its use is limited by nonlinear absorption and adverse events. The current study was undertaken to examine the activity of encochleated atovaquone (eATQ), a novel lipid-crystal nanoparticle formulation, in a mouse model of PCP. eATQ 100-200 mg was superior to commercially available atovaquone at 14 days in decreasing total Pneumocystis nuclei and asci. eATQ plus anidulafungin reduced nuclei significantly better than commercial atovaquone plus anidulafungin. eATQ is a novel formulation of atovaquone that warrants further evaluation for treatment and prevention of PCP.

Pneumocystis jirovecii and toxoplasmosis prophylaxis strategies among pediatric organ transplantation recipients: A US National Survey

There is a paucity of pediatric-specific data to guide consensus recommendations for the prevention of Pneumocystis jirovecii pneumonia (PCP) and toxoplasmosis after solid organ transplantation. We surveyed pediatric transplantation providers and found considerable variability in prophylaxis strategies, despite current guideline recommendations that are based primarily on adult data.

Pneumocystis jiroveci in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of Pneumocystis jiroveci fungal infection transplant recipients. Pneumonia (PJP) may develop via airborne transmission or reactivation of prior infection. Nosocomial clusters of infection have been described among transplant recipients. PJP should not occur during prophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX). Without prophylaxis, PJP risk is greatest in the first 6 months after organ transplantation but may develop later. Risk factors include low lymphocyte counts, cytomegalovirus infection (CMV), hypogammaglobulinemia, treated graft rejection or corticosteroids, and advancing patient age (>65). Presentation typically includes fever, dyspnea with hypoxemia, and cough. Chest radiographic patterns generally reveal diffuse interstitial processes best seen by CT scans. Patients generally have PO₂  < 60 mm Hg, elevated serum lactic dehydrogenase (LDH), and elevated serum (1 → 3) β-d-glucan assay. Specific diagnosis uses respiratory specimens with direct immunofluorescent staining; invasive procedures may be required. Quantitative PCR is a useful adjunct to diagnosis. TMP-SMX is the drug of choice for therapy; drug allergy should be documented before resorting to alternative therapies. Adjunctive corticosteroids may be useful early. Routine PJP prophylaxis is recommended for at least 6-12 months post-transplant, preferably with TMP-SMX.

Pneumocystis pneumonia in HIV-1-infected patients

Pneumocystis pneumonia (PCP) is an opportunistic disease that mainly affects patients with a deficiency of cell-mediated immunity, especially acquired immunodeficiency syndrome (AIDS). The incidence of PCP in these patients has declined substantially owing to the widespread use of antiretroviral therapy and PCP prophylaxis. However, PCP is still a major AIDS-related opportunistic infection, particularly in patients with advanced immunosuppression in whom human immunodeficiency virus type 1 (HIV-1) infection remains undiagnosed or untreated. The clinical manifestations, diagnosis, treatment, and prevention of PCP in patients with HIV-1 infection are addressed in this review.

A Molecular Window into the Biology and Epidemiology of Pneumocystis spp

Pneumocystis, a unique atypical fungus with an elusive lifestyle, has had an important medical history. It came to prominence as an opportunistic pathogen that not only can cause life-threatening pneumonia in patients with HIV infection and other immunodeficiencies but also can colonize the lungs of healthy individuals from a very early age. The genus Pneumocystis includes a group of closely related but heterogeneous organisms that have a worldwide distribution, have been detected in multiple mammalian species, are highly host species specific, inhabit the lungs almost exclusively, and have never convincingly been cultured in vitro, making Pneumocystis a fascinating but difficult-to-study organism. Improved molecular biologic methodologies have opened a new window into the biology and epidemiology of Pneumocystis. Advances include an improved taxonomic classification, identification of an extremely reduced genome and concomitant inability to metabolize and grow independent of the host lungs, insights into its transmission mode, recognition of its widespread colonization in both immunocompetent and immunodeficient hosts, and utilization of strain variation to study drug resistance, epidemiology, and outbreaks of infection among transplant patients. This review summarizes these advances and also identifies some major questions and challenges that need to be addressed to better understand Pneumocystis biology and its relevance to clinical care.

Plasma concentrations of atovaquone given to immunocompromised patients to prevent Pneumocystis jirovecii

Objectives

Atovaquone is one of the alternatives to trimethoprim/sulfamethoxazole for prophylaxis of Pneumocystis jirovecii pneumonia (PCP) in immunocompromised patients. In volunteers, there was wide inter-individual variability in atovaquone bioavailability. The aim of this study was to assess the plasma concentrations of atovaquone in immunocompromised patients under PCP prophylaxis.

Methods

Adult haematology or HIV-positive patients receiving atovaquone (750 mg oral suspension twice a day) for PCP prophylaxis were included. Plasma concentrations were assessed using UV-HPLC, around 12 h after the evening dose (Cmin) and 1-5 h after the morning dose (Cmax).

Results

A total of 82 measurements were performed in 33 patients. This included 19 HSCT recipients, 7 haematology non-transplant patients and 7 HIV-positive patients. The median Cmin (IQR) was 11.3 μg/mL (6.2-27.8) and the median Cmax was 13.4 μg/mL (6.0-28.3). The Cmin and Cmax of atovaquone were not different between HIV-negative and HIV-positive patients, or between HSCT and non-HSCT patients. Atovaquone concentrations were not influenced by the co-administration of valaciclovir (n = 20) or ciclosporin (n = 11), by gut graft-versus-host disease (n = 7) or by the intake of atovaquone with food. Nineteen of the 33 (58%) patients had Cmin <15 μg/mL, a threshold associated with a low rate of clinical response in PCP treatment.

Conclusions

Atovaquone is poorly absorbed in more than half of immunocompromised patients and its bioavailability varies between individuals. These unpredictable variations raise the question of therapeutic drug monitoring, in order to identify patients with low concentrations and those who could benefit from regimen adaptation or from alternatives.

Treatment of Pneumocystis jirovecii pneumonia in HIV-infected patients: a review

INTRODUCTION

Pneumocystis pneumonia is a potentially life-threatening pulmonary infection that occurs in immunocompromised individuals and HIV-infected patients with a low CD4 cell count. Trimethoprim-sulfamethoxazole has been used as the first-line agent for treatment, but mutations within dihydropteroate synthase gene render potential resistance to sulfamide. Despite advances of combination antiretroviral therapy (cART), Pneumocystis pneumonia continues to occur in HIV-infected patients with late presentation for cART or virological and immunological failure after receiving cART. Areas covered: This review summarizes the diagnosis and first-line and alternative treatment and prophylaxis for Pneumocystis pneumonia in HIV-infected patients. Articles for this review were identified through searching PubMed. Search terms included: 'Pneumocystis pneumonia', 'Pneumocystis jirovecii pneumonia', 'Pneumocystis carinii pneumonia', 'trimethoprim-sulfamethoxazole', 'primaquine', 'trimetrexate', 'dapsone', 'pentamidine', 'atovaquone', 'echinocandins', 'human immunodeficiency virus infection', 'acquired immunodeficiency syndrome', 'resistance to sulfamide' and combinations of these terms. We limited the search to English language papers that were published between 1981 and March 2017. We screened all identified articles and cross-referenced studies from retrieved articles. Expert commentary: Trimethoprim-sulfamethoxazole will continue to be the first-line agent for Pneumocystis pneumonia given its cost, availability of both oral and parenteral formulations, and effectiveness or efficacy in both treatment and prophylaxis. Whether resistance due to mutations within dihydropteroate synthase gene compromises treatment effectiveness remains controversial. Continued search for effective alternatives with better safety profiles for Pneumocystis pneumonia is warranted.

Infectious diseases in allogeneic haematopoietic stem cell transplantation: prevention and prophylaxis strategy guidelines 2016

Infectious complications after allogeneic haematopoietic stem cell transplantation (allo-HCT) remain a clinical challenge. This is a guideline provided by the AGIHO (Infectious Diseases Working Group) of the DGHO (German Society for Hematology and Medical Oncology). A core group of experts prepared a preliminary guideline, which was discussed, reviewed, and approved by the entire working group. The guideline provides clinical recommendations for the preventive management including prophylactic treatment of viral, bacterial, parasitic, and fungal diseases. The guideline focuses on antimicrobial agents but includes recommendations on the use of vaccinations. This is the updated version of the AGHIO guideline in the field of allogeneic haematopoietic stem cell transplantation utilizing methods according to evidence-based medicine criteria.

ECIL guidelines for preventing Pneumocystis jirovecii pneumonia in patients with haematological malignancies and stem cell transplant recipients

The 5th European Conference on Infections in Leukaemia (ECIL-5) meeting aimed to establish evidence-based recommendations for the prophylaxis of Pneumocystis jirovecii pneumonia (PCP) in non-HIV-infected patients with an underlying haematological condition, including allogeneic HSCT recipients. Recommendations were based on the grading system of the IDSA. Trimethoprim/sulfamethoxazole given 2-3 times weekly is the drug of choice for the primary prophylaxis of PCP in adults ( A-II: ) and children ( A-I: ) and should be given during the entire period at risk. Recent data indicate that children may benefit equally from a once-weekly regimen ( B-II: ). All other drugs, including pentamidine, atovaquone and dapsone, are considered second-line alternatives when trimethoprim/sulfamethoxazole is poorly tolerated or contraindicated. The main indications of PCP prophylaxis are ALL, allogeneic HSCT, treatment with alemtuzumab, fludarabine/cyclophosphamide/rituximab combinations, >4 weeks of treatment with corticosteroids and well-defined primary immune deficiencies in children. Additional indications are proposed depending on the treatment regimen.

Cost-effectiveness of Prophylaxis Against Pneumocystis jiroveci Pneumonia in Patients with Crohn's Disease

BACKGROUND

Emerging evidence suggests that Pneumocystis jiroveci pneumonia is occurring more frequently in Crohn's disease patients on immunosuppressive medications, especially corticosteroids. Considering its excess mortality and the efficacy of chemoprophylaxis in reducing P. jiroveci pneumonia in acquired immunodeficiency syndrome, there is debate without consensus on the need for chemoprophylaxis in Crohn's disease patients on corticosteroids.

AIMS

We sought to address this debate using insights from simulation modeling.

METHODS

We used a Markov microsimulation model to simulate the natural history of Crohn's disease in 1 million virtual patients receiving appropriate care and who faced P. jiroveci pneumonia risks that varied with corticosteroid use. We examined several chemoprophylaxis strategies and compared their population-level economic and clinical impact using various indices including costs, quality-adjusted life expectancy, and incremental cost-effectiveness ratios. We also performed several nested probabilistic sensitivity analyses to estimate the health and economic impact of chemoprophylaxis in patients on triple immunosuppressive therapy.

RESULTS

At the current PJP incidence, no PJP chemoprophylaxis was the preferred strategy from a population perspective. Considered chemoprophylactic strategies led to higher average costs and fewer P. jiroveci pneumonia cases. However, they also led to lower average quality-adjusted life expectancy and were thus dominated. Nevertheless, these alternative strategies became preferred with progressively higher risks of P. jiroveci pneumonia. Our results also suggest that PJP chemoprophylaxis may be cost-effective in patients on triple immunosuppressive therapy.

CONCLUSION

Our findings support a case-by-case consideration of P. jiroveci pneumonia chemoprophylaxis in Crohn's disease patients receiving corticosteroids.

Pneumocystis Pneumonia in Solid-Organ Transplant Recipients

Pneumocystis pneumonia (PCP) is well known and described in AIDS patients. Due to the increasing use of cytotoxic and immunosuppressive therapies, the incidence of this infection has dramatically increased in the last years in patients with other predisposing immunodeficiencies and remains an important cause of morbidity and mortality in solid-organ transplant (SOT) recipients. PCP in HIV-negative patients, such as SOT patients, harbors some specificity compared to AIDS patients, which could change the medical management of these patients. This article summarizes the current knowledge on the epidemiology, risk factors, clinical manifestations, diagnoses, prevention, and treatment of Pneumocystis pneumonia in solid-organ transplant recipients, with a particular focus on the changes caused by the use of post-transplantation prophylaxis.

Intravenous pentamidine for Pneumocystis carinii/jiroveci pneumonia prophylaxis in pediatric transplant patients

SMX/TMP is the current gold standard for prophylaxis against PCP in immunocompromised pediatric patients. Currently, there are several second-line options for prophylaxis but many, including intravenous (IV) pentamidine, have not been reported to be as effective or as safe as SMX/TMP in the pediatric transplant population. This study is to determine the efficacy and safety of IV pentamidine in preventing PCP in pediatric transplant patients. A retrospective chart review was conducted to evaluate all transplant patients that received at least one dose of IV pentamidine from January 2010 to July 2013. The primary outcome, IV pentamidine efficacy, was evaluated by the incidence of PCP diagnosis for 28 days after the last dose of IV pentamidine if patient was transitioned to another agent for PCP prophylaxis. Patients on IV pentamidine for entire course of PCP prophylaxis were followed at least six months after discontinuation of IV pentamidine. The safety of IV pentamidine was assessed by the incidence of adverse events leading to pentamidine discontinuation. All data were analyzed using descriptive statistics. All transplant patients at CCHMC who had received IV pentamidine were reviewed, and 333 patients met inclusion criteria. The overall incidence of PCP was found to be 0.3% for pediatric transplant patients on pentamidine. Pentamidine was found to be safe, and the incidence of adverse events leading to discontinuation was 6% with the most common reason being tachycardia 2.1%. IV pentamidine is safe and effective as PCP prophylaxis in pediatric transplant patients with a PCP breakthrough rate of 0.3% (1 of 333 patients), and only 20 adverse events led to discontinuation. We recommend that IV pentamidine be considered as a second-line option in pediatric transplant patients who cannot tolerate SMX/TMP.

Identifying the Cause of the "Saturation Gap": Two Cases of Dapsone-induced Methemoglobinemia

Diaphenylsulfone (DDS: Dapsone) is used for Pneumocystis pneumonia (PCP) prophylaxis, and methemoglobinemia has rarely been reported as a side effect of DDS. We herein report two cases of DDS-related methemoglobinemia in an 81-year-old man with organizing pneumonia and an 84-year-old woman with eosinophilic pneumonia under treatment with prednisolone. Both patients initially received trimethoprim/sulfamethoxazole for PCP prophylaxis and were switched to DDS due to side effects and subsequently exhibited a clinically unexplainable decrease in SpO2. Methemoglobinemia was diagnosed based on the findings of arterial blood gas analyses. In both cases, the methemoglobinemia improved after discontinuing DDS.

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.

Hypersensitivity reactions to non beta-lactam antimicrobial agents, a statement of the WAO special committee on drug allergy

Antibiotics are used extensively in the treatment of various infections. Consequently, they can be considered among the most important agents involved in adverse reactions to drugs, including both allergic and non-allergic drug hypersensitivity [J Allergy Clin Immunol 113:832–836, 2004]. Most studies published to date deal mainly with reactions to the beta-lactam group, and information on hypersensitivity to each of the other antimicrobial agents is scarce. The present document has been produced by the Special Committee on Drug Allergy of the World Allergy Organization to present the most relevant information on the incidence, clinical manifestations, diagnosis, possible mechanisms, and management of hypersensitivity reactions to non beta-lactam antimicrobials for use by practitioners worldwide.

Therapy and prophylaxis of opportunistic infections in HIV-infected patients: a guideline by the German and Austrian AIDS societies (DAIG/ÖAG) (AWMF 055/066)

INTRODUCTION

There was a growing need for practical guidelines for the most common OIs in Germany and Austria under consideration of the local epidemiological conditions.

MATERIALS AND METHODS

The German and Austrian AIDS societies developed these guidelines between March 2010 and November 2011. A structured Medline research was performed for 12 diseases, namely Immune reconstitution inflammatory syndrome, Pneumocystis jiroveci pneumonia, cerebral toxoplasmosis, cytomegalovirus manifestations, candidiasis, herpes simplex virus infections, varizella zoster virus infections, progressive multifocal leucencephalopathy, cryptosporidiosis, cryptococcosis, nontuberculosis mycobacteria infections and tuberculosis. Due to the lack of evidence by randomized controlled trials, part of the guidelines reflects expert opinions. The German version was accepted by the German and Austrian AIDS Societies and was previously published by the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF; German Association of the Scientific Medical Societies).

CONCLUSION

The review presented here is a translation of a short version of the German-Austrian Guidelines of opportunistic infections in HIV patients. These guidelines are well-accepted in a clinical setting in both Germany and Austria. They lead to a similar treatment of a heterogeneous group of patients in these countries.

Symptomatic hyperbilirubinemia secondary to dapsone-induced hemolysis and atazanavir therapy

The antiretroviral agent atazanavir is associated with mild asymptomatic hyperbilirubinemia. We report two cases of symptomatic hyperbilirubinemia attributed to atazanavir in conjunction with the Pneumocystis jirovecii pneumonia prophylaxis agent dapsone. Symptoms and laboratory evidence of hemolysis resolved upon discontinuation of dapsone, enabling successful antiretroviral therapy. Symptomatic hyperbilirubinemia due to hemolytic anemia is a potential adverse event when using the combination of atazanavir and dapsone in the treatment of patients with the human immunodeficiency virus.

Projected survival gains from revising state laws requiring written opt-in consent for HIV testing

BACKGROUND

Although the Centers for Disease Control and Prevention recommends HIV testing in all settings unless patients refuse (opt-out consent), many state laws require written opt-in consent.

OBJECTIVE

To quantify potential survival gains from passing state laws streamlining HIV testing consent.

DESIGN

We retrieved surveillance data to estimate the current annual HIV diagnosis rate in states with laws requiring written opt-in consent (19.3%). Published data informed the effect of removing that requirement on diagnosis rate (48.5% increase). These parameters then served as input for a model-driven projection of survival based on consent method. Other inputs included undiagnosed HIV prevalence (0.101%); and annual HIV incidence (0.023%).

PATIENTS

Hypothetical cohort of adults (>13 years) living in written opt-in states.

MEASUREMENTS

Life years gained (LYG).

RESULTS

In the base-case, of the 53,036,383 adult persons living in written opt-in states, 0.66% (350,040) will be infected with HIV. Due to earlier diagnosis, revised consent laws yield 1.5 LYG per HIV-infected person, corresponding to 537,399 LYG among this population. Sensitivity analyses demonstrate that diagnosis rate increases of 24.8-72.3% result in 304,765-724,195 LYG. Net survival gains vanish if the proportion of HIV-infected persons refusing all testing in response to revised laws exceeds 18.2%.

CONCLUSIONS

The potential survival gains of increased testing are substantial, suggesting that state laws requiring opt-in HIV testing should be revised.

High prevalence of Dapsone-induced oxidant hemolysis in North American SCT recipients without glucose-6-phosphate-dehydrogenase deficiency

Dapsone (4-4'-diaminodiphenylsulfone) is commonly used for Pneumocystis jirovecii pneumonia (PCP) prophylaxis in immunocompromised patients. Oxidant hemolysis is a known complication of dapsone, but its frequency in adult patients who have undergone a SCT for hematological malignancies is not well established. We studied the presence of oxidant hemolysis, by combining examination of RBC morphology and laboratory data, in 30 patients who underwent a SCT and received dapsone for PCP prophylaxis, and compared this group with 26 patients who underwent a SCT and received trimethoprim-sulfamethoxazole (TMP-SMX) for PCP prophylaxis. All patients had normal glucose-6-phosphate dehydrogenase (G6PDH) enzymatic activity. In SCT patients, dapsone compared with TMP-SMX for PCP prophylaxis was associated with a high incidence of oxidant hemolysis (87 vs 0%, P<0.001), and the morphological evaluation of oxidant hemolysis correlated well with laboratory evidence of hemolysis. Dapsone-induced oxidant hemolysis in SCT patients is 20-fold higher than the reported rate in the population of HIV-infected patients, and thus much higher than the prevalence of G6PDH variants in the general population. In our patients, it manifested clinically as a lower Hb that was not significant enough to result in increased packed RBC transfusions.

Acute disseminated fatal toxoplasmosis after haploidentical stem cell transplantation despite atovaquone prophylaxis in a young man

We describe a case of fatal acute disseminated breakthrough toxoplasmosis in a 19-year-old adolescent after haploidentical hematopoietic stem cell transplantation for acute lymphoblastic leukemia despite continued atovaquone prophylaxis. Diagnosis was at necropsy, and confirmed by postmortem polymerase chain reaction analysis in plasma. This report illustrates the need for protozoal monitoring despite atovaquone prophylaxis, in severely immunocompromised patients with intolerance to standard treatment.

Management of Pneumocystis Jirovecii pneumonia in HIV infected patients: current options, challenges and future directions

The discovery of the Human Immunodeficiency Virus (HIV) was led by the merge of clustered cases of Pneumocystis jirovecii Pneumonia (PCP) in otherwise healthy people in the early 80’s.1,2 In the face of sophisticated treatment now available for HIV infection, life expectancy approaches normal limits. It has dramatically changed the natural course of HIV from a nearly fatal infection to a chronic disease.3–5 However, PCP still remains a relatively common presentation of uncontrolled HIV. Despite the knowledge and advances gained in the prevention and management of PCP infection, it continues to have high morbidity and mortality rates. Trimethoprim-sulfamethoxazole (TMP-SMZ) remains as the recommended first-line treatment. Alternatives include pentamidine, dapsone plus trimethoprim, clindamycin administered with primaquine, and atovaquone. For optimal management, clinicians need to be familiar with the advantages and disadvantages of the available drugs. The parameters used to classify severity of infection are also important, as it is well known that the adjunctive use of steroids in moderate to severe cases have been shown to significantly improve outcome. Evolving management practices, such as the successful institution of early antiretroviral therapy, may further enhance overall survival rates.

Improving outcomes in state AIDS drug assistance programs

BACKGROUND

State AIDS Drug Assistance Programs (ADAPs) provide antiretroviral medications to patients with no access to medications. Resource constraints limit the ability of many ADAPs to meet demand for services.

OBJECTIVE

To determine ADAP eligibility criteria that minimize morbidity and mortality and contain costs.

METHODS

We used Discrete Event Simulation to model the progression of HIV-infected patients and track the utilization of an ADAP. Outcomes included 5-year mortality and incidence of first opportunistic infection or death and time to starting antiretroviral therapy (ART). We compared expected outcomes for 2 policies: (1) first-come first-served (FCFS) eligibility for all with CD4 count <or=350/microL (current standard) and (2) CD4 count prioritized eligibility for those with CD4 counts below a defined threshold.

RESULTS

In the base case, prioritizing patients with CD4 counts <or=250/microL led to lower 5-year mortality than FCFS eligibility (2.77 vs. 3.27 deaths per 1,000 person-months) and to a lower incidence of first opportunistic infection or death (5.55 vs. 6.98 events per 1,000 person-months). CD4-based eligibility reduced the time to starting ART for patients with CD4 counts <or=200/microL. In sensitivity analyses, CD4-based eligibility consistently led to lower morbidity and mortality than FCFS eligibility.

CONCLUSION

When resources are limited, programs that provide ART can improve outcomes by prioritizing patients with low CD4 counts.

Breakthrough cerebral toxoplasmosis in a patient receiving atovaquone prophylaxis after a hematopoietic stem cell transplantation

We describe a case of breakthrough cerebral toxoplasmosis during atovaquone therapy in a child who was intolerant of conventional prophylactic regimens after hematopoietic stem cell transplantation. The available data on the efficacy of atovaquone prophylaxis in Toxoplasma sero-positive stem cell transplant recipients remain limited, and other strategies, such as preemptive strategy using toxoplasma PCR or TMP-SMX desensitization should be considered in this setting.

Characterization of nebulized buparvaquone nanosuspensions—effect of nebulization technology

The poorly soluble drug buparvaquone is proposed as an alternative treatment of Pneumocystis carinii pneumonia (PCP) lung infections. Physically stable nanosuspensions were formulated in order to deliver the drug at the site of infection using nebulization. The aerosolization characteristics of two buparvaquone nanosuspensions were determined with commercial jet and ultrasonic nebulizer devices. Aerosol droplet size distribution was determined with laser diffractometry (LD). Nebulization of the nanosuspensions and dispersion media surfactant solutions produced aerosol droplets diameters in the range from 3 to 5 microm for Respi-jet Kendall, Pari Turbo Boy system and Multisonic nebulizers and particles around 9-10 microm with Omron U1. Fractions of the nanosuspensions from the nebulizer reservoir and of aerosol produced were collected to investigate changes in the size of the drug nanocrystals influenced by the nebulization technology. Comparisons were performed measuring the drug nanocrystals with photon correlation spectroscopy (PCS) and LD of the samples. Drug particle aggregates were detected in the fractions of aerosol collected from jet nebulizers. Nebulizer technology (jet vs. ultrasonic) showed influence on the stability of the drug particle size distribution of buparvaquone nanocrystals during the nebulization time evaluated.