An approach to intensive antileukemia therapy in patients with previous invasive aspergillosis

Angioinvasive fungal infections impacting the skin: Diagnosis, management, and complications

As discussed in the first article in this continuing medical education series, angioinvasive fungal infections pose a significant risk to immunocompromised and immunocompetent patients alike, with a potential for severe morbidity and high mortality. The first article in this series focused on the epidemiology and clinical presentation of these infections; this article discusses the diagnosis, management, and potential complications of these infections. The mainstay diagnostic tests (positive tissue culture with histologic confirmation) are often supplemented with serum biomarker assays and molecular testing (eg, quantitative polymerase chain reaction analysis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry) to ensure proper speciation. When an angioinvasive fungal infection is suspected or diagnosed, further workup for visceral involvement also is essential and may partially depend on the organism. Different fungal organisms have varied susceptibilities to antifungal agents, and knowledge on optimal treatment regimens is important to avoid the potential complications associated with undertreated or untreated fungal infections.

Paediatric HIV infection in Western Africa: the long way to the standard of care

In sub-Saharan Africa, newborns and children continue to suffer from insufficient access to early diagnosis and antiretroviral (ARV) treatments. A survey had been conducted in Burkina Faso, Ghana and Ivory Coast, from January 2010 to February 2011 to identify the major challenges regarding HIV prophylaxis and treatment of children in western Africa. The results of this survey highlight that only a small proportion of HIV-exposed newborns receive ARV prophylaxis. However, this problem is often not perceived at the national level. The problem could be faced by improving the communication process between the peripheral health services and the national procurement system. Moreover, supporting the development of local pharmaceutical industries could facilitate the availability of child-sized drugs, contextualized to the socio-cultural needs of such area, adequate not only in terms of efficacy, safety and tolerability, but also in terms of palatability, storage, distribution and cost.

Clinical practice guideline for the use of antimicrobial agents in neutropenic patients with cancer: 2010 update by the infectious diseases society of america

This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia. Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving. What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens. Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care-associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Executive Summary: Clinical Practice Guideline for the Use of Antimicrobial Agents in Neutropenic Patients with Cancer: 2010 Update by the Infectious Diseases Society of America

This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia.

Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving.

What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens.

Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care–associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Acute Myelogenous Leukemia and Febrile Neutropenia

Aggressive chemotherapy has a deleterious effect on all components of the defense system of the human body. The resulting neutropenia as well as injury to the pulmonary and gastrointestinal mucosa allow pathogenic micro-organisms easy access to the body. The symptoms of an incipient infection are usually subtle and limited to unexplained fever due to the absence of granulocytes. This is the reason why prompt administration of antimicrobial agents while waiting for the results of the blood cultures, the so-called empirical approach, became an undisputed standard of care. Gram-negative pathogens remain the principal concern because their virulence accounts for serious morbidity and a high early mortality rate. Three basic intravenous antibiotic regimens have evolved: initial therapy with a single antipseudomonal β-lactam, the so-called monotherapy; a combination of two drugs: a β-lactam with an aminoglycoside, a second β-lactam or a quinolone; and, thirdly, a glycopeptide in addition to β-lactam monotherapy or combination. As there is no single consistently superior empirical regimen, one should consider the local antibiotic susceptibility of bacterial isolates in the selection of the initial antibiotic regimen. Not all febrile neutropenic patients carry the same risk as those with fever only generally respond rapidly, whereas those with a clinically or microbiologically documented infection show a much slower reaction and less favorable response rate.

Once an empirical antibiotic therapy has been started, the patient must be monitored continuously for nonresponse, emergence of secondary infections, adverse effects, and the development of drug-resistant organisms. The averageduration of fever in serious infections in eventually successfully treated neutropenic patients is 4–5 days. Adaptations of an antibiotic regimen in a patient who is clearly not responding is relatively straightforward when a micro-organism has been isolated; the results of the cultures, supplemented by susceptibility testing, will assist in selecting the proper antibiotics. The management of febrile patients with pulmonary infiltrates is complex. Bronchoscopy and a high resolution computer-assisted tomographic scan represent the cornerstones of all diagnostic procedures, supplemented by serological tests for relevant viral pathogens and for aspergillosis. Fungi have been found to be responsible for two thirds of all superinfections that may surface during broad-spectrum antibiotic treatment of neutropenic patients. Antibiotic treatment is usually continued for a minimum of 7 days or until culture results indicate that the causative organism has been eradicated and the patient is free of major signs and symptoms. If a persistently neutropenic patient has no complaints and displays no evidence of infection, early watchful cessation of antibiotic therapy or a change to the oral regimen should be considered.

Salvage therapy with abacavir and other reverse transcriptase inhibitors for human immunodeficiency-associated encephalopathy

BACKGROUND

HIV-associated encephalopathy (HIV-AE) is a severe neurologic condition that affects HIV-infected children. The potential benefit of antiretroviral (ARV) agents with good cerebrospinal fluid (CSF) penetration remains to be defined. Abacavir (ABC) achieves good CSF concentrations and studies of high-dose ABC showed benefit in adults with HIV dementia. The present study evaluated the safety and virologic, immunologic and neuropsychological responses of an ARV regimen including high-dose ABC in children with HIV-AE.

METHODS

Children between 3 months and 18 years old and abacavir-naive with HIV-AE and virologic failure were eligible.

RESULTS

: Seventeen children (16 ARV-experienced) were enrolled and 14 children completed 48 weeks of therapy. The overall tolerability was good; 2 children had a possible hypersensitivity reaction. At week 48, 53% and 59% of the children achieved HIV RNA levels below the limit of quantitation in plasma and CSF, respectively. The median (25%-75% range) change of HIV RNA from baseline to week 48 was -2.29 (-0.81 to -2.47) log10 copies/mL in plasma and -0.94 (0 to -1.13) log10 copies/mL in CSF. The mean increases in CD4 (+/-standard error of mean) cell count and CD4% were 427 (+/-169) cells/mm and 8% (+/-2), respectively. Concentrations of soluble tumor necrosis factor receptor II were reduced in plasma and CSF. Children less than 6 years of age demonstrated significant neuropsychological improvement at week 48.

CONCLUSIONS

In the present study with a limited number of children, highly active ARV therapy including high-dose ABC showed a safety profile similar to standard dose ABC and provided clinical, immunologic and virologic response in children with HIV-AE at week 48. Children less than 6 years of age also demonstrated significant neuropsychological improvement.

Spontaneous formation of vesicles

his review highlights the relevant issues of spontaneous formation of vesicles. Both the common characteristics and the differences between liposomes and vesicles are given. The basic concept of the molecular packing parameter as a precondition of vesicles formation is discussed in terms of geometrical factors, including the volume and critical length of the amphiphile hydrocarbon chain. According to theoretical considerations, the formation of vesicles occurs in the systems with packing parameters between 1/2 and 1. Using common as well as new methods of vesicle preparation, a variety of structures is described, and their nomenclature is given. With respect to sizes, shapes and inner structures, vesicles structures can be formed as a result of self-organisation of curved bilayers into unilamellar and multilamellar closed soft particles. Small, large and giant uni-, oligo-, or multilamellar vesicles can be distinguished. Techniques for determination of the structure and properties of vesicles are described as visual observations by optical and electron microscopy as well as the scattering techniques, notably dynamic light scattering, small angle X-ray and neutron scattering. Some theoretical aspects are described in short, viz., the scattering and the inverse scattering problem, angular and time dependence of the scattering intensity, the principles of indirect Fourier transformation, and the determination of electron density of the system by deconvolution of p(r) function. Spontaneous formation of vesicles was mainly investigated in catanionic mixtures. A number of references are given in the review.

Clinical Issues Regarding Relapsing Aspergillosis and the Efficacy of Secondary Antifungal Prophylaxis in Patients with Hematological Malignancies

Advancements in early diagnosis and the introduction of effective agents have improved the rates of response of aspergillosis to primary antifungal therapy. These changes allow the subsequent continuation of cytotoxic chemotherapy and/or performance of hematopoietic stem cell transplantation in an increasing number of patients with hematological malignancies. These developments have increased interest in secondary prophylaxis of aspergillosis, because the resumption of myelotoxic chemotherapy in these patients is associated with high rates of relapse of this opportunistic mycosis in the absence of prophylaxis. However, the risk factors for relapsing invasive aspergillosis and the strategies for reducing risk are not well defined. Furthermore, differentiating aspergillosis relapse from reinfection with a new Aspergillus isolate is problematic when using the available laboratory tools. We summarize the existing knowledge regarding the pathogenesis of, risk factors for, and natural history of relapsing invasive aspergillosis and review the limited data regarding the role of secondary antifungal prophylaxis.

Empiric antifungal therapy in neutropenic cancer patients

Hematopoietic stem cell transplant recipients and those patients with acute leukemia are at greatest risk for invasive fungal infections particularly due to Candida and Aspergillus species during periods of profound neutropenia. Empiric antifungal therapy in persistently febrile neutropenic patients has been adopted as a standard of care. Antifungal therapeutic options include: amphotericin B, lipid formulations of amphotericin B, fluconazole, itraconazole, voriconazole, and caspofungin. Amphotericin B preparations offer a beneficial effect for survival, defervescence, and a decrease in breakthrough fungal infections. Lipid formulations of amphotericin B may provide beneficial effects over amphotericin B with regard to survival, treatment of baseline fungal infection, breakthrough fungal infection, and fewer discontinuations due to lack of efficacy. Amphotericin B compounds produce a trend for better outcomes in defervescence, treatment of baseline fungal infections, prevention of breakthrough infections, and avoidance of discontinuation compared with the azoles. Caspofungin is also effective. The optimal empiric antifungal agent and the precise time of initiation remain to be determined.

A new era of antifungal therapy

Invasive fungal infections pose major management problems for clinicians caring for hematopoietic cell transplant patients. Two major fungal genera, Candida and Aspergillus, account for most fungal infections. Rates of systemic Candida infection range from 15% to 25%, mostly in the pre-engraftment period. Prophylaxis by fluconazole has dramatically reduced the frequency of early Candida infections. Caspofungin has recently been shown to offer an excellent alternative to amphotericin B (with less toxicity) or fluconazole (with a broader spectrum) for therapy of systemic Candida infections. Aspergillus infections occur in 15% to 20% of allogeneic hematopoietic cell transplant patients, most frequently in the post-engraftment period; they are associated with a severe diminution of cell-mediated immune responses by graft-versus-host disease and prolonged corticosteroid use. Voriconazole, a recently introduced broad-spectrum azole, has excellent activity against Aspergillus and is generally well tolerated. Voriconazole currently offers the best prospect for success and tolerance as a first-line treatment for aspergillosis. Second-line therapies include lipid formulations of amphotericin B, caspofungin, or intravenous itraconazole. Unfortunately, early initiation of therapy for aspergillosis is frequently not possible because of inaccurate diagnostics. One new diagnostic, the galactomannan assay, has recently been approved, and others are in development; these offer promise for earlier diagnosis without the need for invasive procedures. It is hoped that these new therapies and new diagnostics will usher in a new era of antifungal therapy.

Secondary antifungal prophylaxis with voriconazole to adhere to scheduled treatment in leukemic patients and stem cell transplant recipients

Although the efficacy and safety of voriconazole to treat invasive fungal infections have been demonstrated in prospective trials, its use for secondary prophylaxis to prevent reactivation of these infections remains unknown. Delaying the scheduled treatment of leukemia until complete resolution of fungal infection may have major implications for prognosis. We report 11 leukemic patients with previous aspergillus (n=10) and candida (n=1) infection who received voriconazole 400 mg/day intravenously or orally for between 44 and 245 days. Nine patients were scheduled for allogeneic stem cell transplant, and two for consolidation therapy for acute leukemia. None of the patients had a relapse of fungal infection, and scheduled treatment was delayed only once. Voriconazole was well tolerated, except in one patient who had abnormal liver tests secondary to hepatic graft-versus-host disease, and one who had visual disturbances. This small but homogeneous series indicates that voriconazole may be useful to prevent fungal relapse during at-risk periods in leukemic patients. Prospective trials are warranted to confirm these encouraging results.

Antifungal prophylaxis with azole derivatives

In recent years, several reports have underlined the increasing role of fungal infections as a cause of morbidity and mortality in hospitalised patients. For this reason, and also in light of the high mortality rate associated with these infections, chemoprophylaxis has been advocated by several authors. The available evidence suggests that both fluconazole and itraconazole are able to decrease candida colonisation and infection, when compared with placebo or with nonabsorbable antifungals. Data seem also to suggest that a decrease in fungus-related mortality can be achieved with prophylaxis, although with little effect on overall mortality, probably because of the importance of severe underlying diseases. Itraconazole proved to be effective in the prevention of fungal infections, including invasive aspergillosis, although with increased incidence of side-effects, often leading to treatment discontinuation. The other side of the coin is that antifungal prophylaxis might have untoward effects, such as the selection of triazole-resistant Candida strains or the induction of resistance. In addition, some authors have suggested that the use of triazoles might modulate the pattern of infecting organisms in cancer patients, increasing the risk of both aspergillosis and bacteremia. In conclusion, antifungal prophylaxis with triazole antifungals should be used with caution, only in patients at high risk for invasive fungal infections. These include allogeneic bone marrow transplant patients (especially those with mismatched or unrelated donors), acute myeloid leukaemia patients treated with high-dose cytarabine (C-ara), very-low-birth-weight infants, patients with chronic granulomatous disease, and high-risk surgical and intensive-care unit patients.

Polymerase chain reaction aids in the diagnosis of an unusual case of Aspergillus niger endocarditis in a patient with acute myeloid leukaemia

Endocarditis secondary to Aspergillus niger has not been described in a leukaemic patient. We describe a case of A. niger endocarditis in a patient with acute myeloid leukaemia and refractory fever. The microbiological cause of his endocarditis was initially misdiagnosed because he fulfilled the Duke criteria for enterococcal endocarditis. A polymerase chain reaction test utilizing pan-fungal primers detected a product from an Aspergillus sp. The DNA was subsequently sequenced and was found to have 100% homology with A. niger. A postmortem revealed fungal endocarditis secondary to disseminated aspergillosis, without evidence of bacterial endocarditis. The patient was found to have a lung aspergilloma that was possibly occupationally acquired, and may have been long standing.

Voriconazole in the management of invasive aspergillosis in two patients with acute myeloid leukemia undergoing stem cell transplantation

The management of invasive aspergillosis in patients with hematological malignancies remains controversial. A major problem is how to manage patients who had invasive aspergillosis during remission induction and consolidation therapy and then undergo SCT. Indeed in these patients the mortality rate related to invasive aspergillosis recurrence remains unacceptably high. We report two cases of patients who underwent remission induction for AML, developed invasive aspergillosis during antifungal prophylaxis with itraconazole, failed amphotericin B deoxycholate and liposomal amphotericin B treatment, were successfully treated with voriconazole and eventually underwent SCT with voriconazole prophylaxis without reactivation of invasive aspergillosis.

Antifungal chemoprophylaxis after blood and marrow transplantation

Invasive fungal infections are common and deadly in recipients of blood and marrow transplants. Current diagnostic techniques do not allow accurate early diagnosis, especially of infection with mould pathogens, and delays in diagnosis are associated with treatment failure. This lack of early diagnosis has provided the impetus for the development of antifungal prophylaxis. Fluconazole prophylaxis is highly effective for the control of invasive yeast infections and associated with few breakthrough infections. The development of antimould prophylaxis in this patient population is a high priority.

Invasive fungal infections: evolving challenges for diagnosis and therapeutics

Invasive fungal infections (IFI) parallel the explosive increase in the immunocompromized patient population, and are characterized by diagnostic difficulties and extreme mortality. Candidemia in a tertiary referral hospital in the Middle East confirms the current epidemiologic shift in this common blood stream pathogen towards non-malignancy cases (38%) and antifungal prophylaxis failure (20%), high presentation sepsis scores and attributable mortality (32%). Invasive aspergillosis (IA) is also associated with high mortality. Use of non-invasive computerized tomographic (CT) radiologic scanning linked to early administration of high dose liposomal amphotericin B (LAB) is associated with a reduced mortality of 9.5% compared to historical experience of 28%.Life threatening invasive aspergillosis also occurs in patients who are less obviously immunocompromized. Investigations may reveal subtle immune deficits which could place the patient at some risk for an invasive mycosis. Antifungal treatment used in combination with progenitor cell growth factors and gamma-interferon has proved successful in such situations of progressive fungal disease unresponsive to antifungal therapy alone. Pharmacologic remodeling of existing compounds by lipidisation reduces both the toxicity denominator and the efficacy numerator of the therapeutic index when compared to the parent drug. A comparative dose study of liposomal amphotericin B in aspergillosis has demonstrated equi-efficacy, generated debate over the ability of the controlled clinical trial to be capable of assessing antifungal efficacy, and illustrated that recovery from an invasive fungal infection may require maximum tolerated doses and immunomanipulation. Several new antifungal strategies are under clinical investigation. These include reformulating existing antifungals, exploitation of the growing knowledge of virulence factors to synthesize antagonists, immune reconstitution and immunoprotection. An interim analysis of an ongoing placebo controlled study of recombinant interleukin-11 to assess its efficacy in reducing sepsis in leukemia patients through prevention of chemotherapy induced gut epithelial cell apoptosis, has demonstrated a difference in the two study arms in sepsis rates and preservation of gastrointestinal epithelial cell integrity. The unique and special challenges presented by the dynamic epidemiologics of invasive fungal infections are demanding and attracting considerable responses, in the fields of diagnosis and therapeutics. Current strategies need considerable improvement, yet ongoing collaborative efforts will have a positive impact on our understanding of the fungus-host interaction and ultimately our ability to offer better care for our patients with invasive mycoses.

Liposomal amphotericin B for prophylaxis of invasive fungal infections in high-risk paediatric patients with chemotherapy-related neutropenia: interim analysis of a prospective study

Invasive fungal infections (IFI) are a major cause of morbidity and mortality in patients with cancer. A retrospective analysis of children with cancer at high risk for IFI treated at Münster University Hospital showed that the incidence (7.4% vs. 1.8%) and lethality (28.1% vs. 0) of documented IFI were lower in patients receiving systemic antifungal prophylaxis with liposomal amphotericin B (l-AmB) in comparison to a historical control group. To determine whether this decline in incidence and lethality was due to antifungal prophylaxis or was produced by advances in diagnostic procedures and early empirical antifungal therapy, a prospective study was initiated. Patients in the prophylaxis arm received thrice-weekly 1 mg kg(-1) body weight l-AmB, whilst patients in the early intervention arm received no prophylaxis. Diagnostic procedures and antifungal therapy for suspected or proven IFI were initiated as clinically indicated for all patients. The primary endpoint of the study was the incidence of IFI. Secondary endpoints were the use of therapeutic doses of l-AmB, the safety of prophylactic l-AmB, and the total consumption of l-AmB for antifungal therapy. The interim analysis after 1 year showed no differences between the two approaches with respect to the incidence of IFI and to safety issues.

Treatment of documented and suspected neutropenia-associated invasive fungal infections

Factors such as the intensification of anti-tumor regimens have enhanced both the depth and length of neutropenia and endorsed severe deficiencies in other immune systems. As a result, the risk of fungal infections has increased substantially. Clinicians should be aware of the possibility to enable a timely diagnosis because many of the problems in the management of invasive fungal infections during neutropenia are as much the consequence of diagnostic short-comings as of lack of therapeutic options. About 7% of all febrile episodes during neutropenia can ultimately be attributed to fungi, Candida and Aspergillus species being the paramount pathogens. Although the data in favor of prophylactic use of antifungals are not convincing, prophylaxis is still recommended in an attempt to protect particularly high-risk patients. Fluconazole still appears a suitable agent in recipients of a bone marrow transplant. Given the paucity of data, reappraisal of the value of empirical antifungal therapy is warranted. Amphotericin B with or without 5-flucytosine is considered the standard therapy for acute candidiasis with fluconazole as an alternative. Amphotericin B is also first-line therapy for invasive aspergillosis in neutropenic patients; lipid-based formulations are recommended for patients who develop nephrotoxity. Recovery of the granulocytes and other immune systems has shown to be of critical importance in the management of all invasive fungal infections.

Prevention and prophylaxis of invasive fungal sinusitis in the immunocompromised patient

Fungal infections are a leading cause of morbidity and mortality among immunocompromised patients. Invasive fungal sinusitis is a devastating complication of immunosuppression. Treatment options are limited and often ineffective, making prevention important. Measures to decrease environmental exposure, indications for antifungal prophylaxis, and limitations of current regimens are discussed.

Five-year-survey of invasive aspergillosis in a paediatric cancer centre. Epidemiology, management and long-term survival

The epidemiology, management, and long-term survival of invasive aspergillosis was assessed in a prospective, 5-year observational study in 346 unselected paediatric cancer patients receiving dose-intensive chemotherapy for newly diagnosed or recurrent malignancies. Invasive aspergillosis occurred exclusively in the context of haematological malignancies, where it accounted for an incidence of 6.8% (n = 13 of 189). The lung was the primary site in 12 cases, and dissemination was present in three of those. Prior to diagnosis, the overwhelming majority of patients had been profoundly neutropenic for at least 14 days (n = 11 of 13) and were receiving systemic antifungal agents (n = 10 of 13). Clinical signs and symptoms were nonspecific but always included fever. All 11 patients who were diagnosed and treated during lifetime for a minimum of 10 days responded to either medical or combined medical and surgical treatment, and seven were cured (64%). Nevertheless, the overall long-term survival was merely 31% after a median follow-up of 5.68 years after diagnosis. Apart from refractory or recurrent cancer, the main obstacles to successful outcome were failure to diagnose IA during lifetime and bleeding complications in patients with established diagnosis. The frequency of invasive aspergillosis of greater than 15% in paediatric patients with acute myeloblastic leukaemia and recurrent leukaemias warrants the systematic investigation of preventive strategies in these highly vulnerable subgroups.

Invasive aspergillosis in neutropenic patients: rapid neutrophil recovery is a risk factor for severe pulmonary complications

BACKGROUND

In invasive aspergillosis, the duration of neutropenia is an accepted risk factor, and recovery from neutropenia is generally associated with a favourable outcome. However, the rapidity of granulocyte recovery may rarely be associated with adverse sequelae. The purpose of this study was to define the relationship between neutrophil (polymorphonuclear, PMN) recovery after chemotherapy-induced bone marrow aplasia and the occurrence of severe pulmonary complications (haemoptysis, pneumothorax and death) in patients with haematological malignancies who developed invasive fungal pneumonias.

METHODS

Twenty consecutive patients were retrospectively studied; eight of them had developed pulmonary events between 5 and 11 days after neutrophil recovery that followed deep neutropenia (PMN < 100 microL-1).

RESULTS

Five patients had haemoptysis (one of these also had pneumothorax) and three had pneumothorax. According to the multiplicative logistic model, the odds of occurrence of a pulmonary event increased significantly with increasing PMN count on the fifth day (P < 0.001). Five of the eight patients who had pulmonary complications died. Also, the risk of death was larger in the presence of rapid neutrophil recovery, although the difference was not statistically significant (P = 0.111). Analysis of clinical and laboratory data showed that the risk of pulmonary complications significantly increased when the neutrophil concentration was > 4500 microL-1 on day 5 after deep granulocyte neutropenia (PMN < 100 microL-1). There was no correlation between pulmonary complications, dosage of amphotericin B and deaths.

CONCLUSION

The occurrence of life-threatening complications in patients with invasive fungal pneumonia is closely related to rapid PMN recovery.

Treatment of fungal infections in neutropenic children

Fungal infections have emerged as one of the most significant complications of antineoplastic therapy and marrow transplantation in children. Morbidity and mortality associated with fungal infections are high. Recent trends indicate that the incidence and spectrum of fungal infections are increasing, partly because of the increase in the number of children receiving intensive chemotherapy and marrow transplantation, but also because of the successful management of bacterial and viral infections. Though many factors may contribute to risk for developing a fungal infection, prolonged neutropenia is the most important. Until recently, options for antifungal therapy were limited. Advances include less toxic formulations of amphotericin B and an expanding armamentarium of azoles as well as new antifungal compounds. This review addresses the therapeutic options available for treatment of fungal infections in immunocompromised children.

Antifungal susceptibility of Aspergillus species isolated from invasive oral infection in neutropenic patients with hematologic malignancies

OBJECTIVE

The aim of this study was to evaluate the relevance of in vitro antifungal susceptibility to clinical response in neutropenic patients with invasive oral aspergillosis.

STUDY DESIGN

Nine isolates of Aspergillus species were obtained from invasive oral infections in 9 patients with hematologic malignancies and tested for their in vitro susceptibility to amphotericin B, fluconazole, miconazole, 5-fluorocytosine, and itraconazole. Minimal inhibitory concentration values of the 5 drugs were obtained for each fungus through use of a microdilution broth method. The patients were treated with intravenous amphotericin B (30-50 mg/day) in combination with oral 5-fluorocytosine (3000-6000 mg/day) and/or oral itraconazole (200 mg/day).

RESULTS

Amphotericin B and itraconazole were found to be very active, with minimal inhibitory concentration values of 0.861 and 0.194 microg/mL, respectively. Miconazole and 5-fluorocytosine showed minimal inhibitory concentration values of 1.72 and 3.56 microg/mL, respectively. On the other hand, fluconazole FCZ showed low activity, with a minimal inhibitory concentration value in excess of 64.0 microg/mL. During neutropenia, combined antifungal chemotherapy stabilized oral aspergillosis and prevented the spread of oral lesions in 8 patients in whom neutrophil counts eventually recovered.

CONCLUSIONS

The results imply that in vitro susceptibility testing may serve as an informative parameter with respect to the efficacy of these antifungals in the treatment of invasive oral aspergillosis, inducing fungal stasis until the neutrophils recover.

Antifungal agents. Part I. Amphotericin B preparations and flucytosine

Traditionally, amphotericin B has been the cornerstone of antifungal treatment. Toxicity, however, is a major dose-limiting factor of amphotericin B deoxycholate. Nevertheless, it continues to have a major role in the treatment of deep-seated mycotic infections. Recently, less nephrotic lipid formulations, including amphotericin B lipid complex, amphotericin B cholesteryl sulfate, and liposomal amphotericin B, have been introduced. The pharmacologic properties, main indications, recommended dosages, related costs, and adverse effects of these various preparations are summarized in this review. Orally administered flucytosine is useful in certain infections, particularly cryptococcal meningitis, but it should be used with caution in patients with renal insufficiency.

Liposomal amphotericin B compared with amphotericin B deoxycholate in the treatment of documented and suspected neutropenia-associated invasive fungal infections

It has been suggested that a better outcome of neutropenia-associated invasive fungal infections can be achieved when high doses of lipid formulations of amphotericin B are used. We now report a randomized multicentre study comparing liposomal amphotericin B (AmBisome, 5 mg/kg/d) to amphotericin B deoxycholate (AmB, 1 mg/kg/d) in the treatment of these infections. Of 106 possible patients, 66 were enrolled and analysed for efficacy: nine had documented fungaemia, 17 had other invasive mould infections and 40 had suspected pulmonary aspergillosis. After completion of the course medication, in the AmBisome group (n = 32) 14 patients had achieved complete response, seven a partial response and 11 were failures as compared to 6, 13 and 15 patients (n = 34) treated with AmB (P=0.09); P=0.03 for complete responders. A favourable trend for AmBisome was found at day 14, in patients with documented infections and in patients with pulmonary aspergillosis (P=0.05 and P=0.096 respectively). Mortality rates were lower in patients treated with AmBisome (adjusted for malignancy status, P=0.03). More patients on AmB had a >100% increase of their baseline serum creatinine (P<0.001). The results indicate that, in neutropenic patients with documented or suspected invasive fungal infections AmBisome 5 mg/kg/d was superior to AmB 1 mg/kg/d with respect to efficacy and safety.

The epidemiology and prevention of invasive aspergillosis

Over the past two decades, the incidence of invasive aspergillosis (IA) has risen inexorably. This is almost certainly the consequence of the more widespread use of aggressive cancer chemotherapy regimens, the expansion of organ transplant programmes and the advent of the acquired immunodeficiency syndrome (AIDS) epidemic. Despite the development of new approaches to therapy, IA still remains a life-threatening infection in immunocompromised patients and is the most important cause of fungal death in cancer patients. It is clear that the prevention of severe fungal infection by the use of effective infection control measure should be the priority of the teams involved in managing at-risk patients. The evidence from clinical and molecular epidemiological studies is reviewed and current thinking on sources and routes of transmission of the organism are discussed. Our increasing understanding of these has led to the development of a variety of environmental and general strategies for the prevention of IA. It is anticipated that these, coupled with the use of prophylactic antifungal agents active against Aspergillus spp., will have a significant impact upon the morbidity and mortality associated with this infection.

Prophylaxis of fungal infections

Considering the high morbidity and mortality of deep-seated opportunistic mycoses in severely immunosuppressed patients, strategies for prophylaxis appear to be indicated. Exposure to Aspergillus spp. can be prevented by air filtration which has been shown to reduce the rate of infection. However, Candida infections are predominantly caused by colonizing fungi; therefore drug prophylaxis is more promising. Prospective randomized studies proved the effectiveness of fluconazole (FLU) to prevent infections in patients after bone marrow transplantation.

Aggressive surgical management in localized pulmonary mycotic and nonmycotic infections for neutropenic patients with acute leukemia: report of eighteen cases

OBJECTIVE

To prevent hemoptysis and relapse during subsequent chemotherapy-induced neutropenia in patients with localized forms of invasive pulmonary aspergillosis, we adopted an aggressive surgical approach.

METHODS

From 1988 to 1996, 18 patients with hematologic diseases were referred with the diagnosis of localized invasive pulmonary aspergillosis. The diagnosis was based on clinical features, failure to respond to antibiotic therapy, an air crescent sign suggestive of aspergillosis on the computed tomographic scan (39%), and retrieval of fungi by bronchoalveolar lavage (44%).

RESULTS

The following procedures were done: one pneumonectomy, four bilobectomies, seven lobectomies, six wedge resections, and one lobectomy with wedge resection (one patient had two procedures). No perioperative deaths or complications occurred. The histologic examination confirmed the diagnosis of invasive pulmonary aspergillosis in 12 patients. The six other diagnoses were as follows: one case of classic aspergilloma, one case of pneumonia, and four cases of pulmonary abscess. According to univariate analysis, thoracic pain was less common in the group with noninvasive pulmonary aspergillosis (1/6) than in the group with invasive pulmonary aspergillosis (8/12) (p < 0.05). Sixteen patients required subsequent hematologic treatments. Sixty-six percent of the patients are alive with a mean follow-up of 29.1 +/- 27.8 months (range 2 to 103 months), with no statistically significant difference between the invasive and the noninvasive pulmonary aspergillosis groups. Five patients died of a recurrence of their malignant disease at a mean of 17.2 +/- 12.5 months (range 2 to 30 months), and one had a cerebral recurrence of Aspergillus infection during a bone marrow transplantation 3 months later.

CONCLUSION

Aggressive surgical management radically improves the prognosis of invasive pulmonary aspergillosis, even if the surgical indications include some nonmycotic infections because of the difficulty in establishing the clinical diagnosis.

Antifungal prophylaxis during neutropenia and immunodeficiency

Fungal infections represent a major source of morbidity and mortality in patients with almost all types of immunodeficiencies. These infections may be nosocomial (aspergillosis) or community acquired (cryptococcosis), or both (candidiasis). Endemic mycoses such as histoplasmosis, coccidioidomycosis, and penicilliosis may infect many immunocompromised hosts in some geographic areas and thereby create major public health problems. With the wide availability of oral azoles, antifungal prophylactic strategies have been extensively developed. However, only a few well-designed studies involving strict criteria have been performed, mostly in patients with hematological malignancies or AIDS. In these situations, the best dose and duration of administration of the antifungal drug often remain to be determined. In high-risk neutropenic or bone marrow transplant patients, fluconazole is effective for the prevention of superficial and/or systemic candidal infections but is not always able to prolong overall survival and potentially selects less susceptible or resistant Candida spp. Primary prophylaxis against aspergillosis remains investigative. At present, no standard general recommendation for primary antifungal prophylaxis can be proposed for AIDS patients or transplant recipients. However, for persistently immunocompromised patients who previously experienced a noncandidal systemic fungal infection, prolonged suppressive antifungal therapy is often indicated to prevent a relapse. Better strategies for controlling immune deficiencies should also help to avoid some potentially life-threatening deep mycoses. When prescribing antifungal prophylaxis, physicians should be aware of the potential emergence of resistant strains, drug-drug interactions, and the cost. Well-designed, randomized, multicenter clinical trials in high-risk immunocompromised hosts are urgently needed to better define how to prevent severe invasive mycoses.

[Preventive antimycotic therapy of neutropenic and immunosuppressed patients]

Fungal infections are of increasing importance in severely neutropenic and immunosuppressed patients because of their high incidence and their high mortality once systemic dissemination has occurred. Various prophylactic strategies have been developed that include environmental measures as well as topical and systemic antimycotic prophylaxis. In this review the causative pathogens and patients at risk for developing fungal infections will be identified. Specific strategies will be discussed for each patient population and suggestions made for areas of future research.

Practical modalities for prevention of fungal infections in cancer patients

Invasive fungal infections have become a major obstacle to the treatment of patients with malignancies. Candida spp. and Aspergillus spp. now rank among the ten most prominent pathogens in these patients. Currently, there are no adequate means of detecting these infections at an early stage, and optimal hygiene and elimination of well-known sources of infection remain the most important preventive measures. Due to the lack of reliable, randomized studies, the role of antifungal drugs in the prevention of invasive fungal infections is difficult to judge. The clinical impact of the older oral antifungal agents is questionable, and compliance with therapeutic regimens of these drugs is often limited. In prospective studies in bone marrow transplant recipients, fluconazole was effective in preventing candidiasis but offered no prophylaxis against infections due to Aspergillus spp. and other molds. Initial trials on the use of sprays and aerosols of amphotericin B and on infusions of low doses of this drug appeared beneficial, but the number of patients included was too small to allow any definite conclusion. Itraconazole offers promise, but it can only be given orally; adequate, reliable absorption is not yet guaranteed. While the lack of data justifies a wait-and-see approach in patients at low or moderate risk of developing a fungal infection, it seems reasonable to administer prophylaxis to high-risk patients, even though there is presently no single agent suitable for all prophylactic purposes.

Vertical human immunodeficiency virus-1 infection: involvement of the central nervous system and treatment

Involvement of the central nervous system (CNS) contributes substantially to morbidity and mortality of vertical infection with the human immunodeficiency virus (HIV)-1. The clinical spectrum ranges from minor developmental disabilities to severe and progressive encephalopathy. Progression of the disease varies considerably. Both direct viral and indirect host-related pathogenic mechanisms have been proposed. The diagnosis depends on neurological and neurodevelopmental assessments. So far, HIV-1-specific antiviral treatment has shown limited effects on neurological manifestations in symptomatic children. Thus, efforts are needed to improve prevention and treatment of CNS involvement. It is still unclear whether early use of antiretroviral agents is of benefit.

CONCLUSION

Since experience of treatment of HIV-1 infections in adults cannot easily be translated to children, paediatric clinical trials are needed to answer questions specific to the unique characteristics of children.

Recent progress and current problems in treatment of invasive fungal infections in neutropenic patients

Invasive fungal infections, including disseminated candidiasis and invasive pulmonary aspergillosis, are important causes of morbidity and mortality in neutropenic patients. The recent development of fluconazole, itraconazole, lipid formulations of amphotericin B, and recombinant cytokines have expanded our therapeutic armamentarium. Clinical trials have elucidated new strategies for utilizing these compounds in the prevention and treatment of opportunistic mycoses. The population of more severely immunocompromised patients, however, continues to expand and the spectrum of drug-resistant fungi, including but not limited to Candida spp, Fusarium spp, Zygomycetes, and dematiaceous moulds, continues to evolve, thus presenting new challenges to recent therapeutic advances. Development of new antifungal chemotherapeutic agents and novel approaches for augmentation of host response will be required to meet these new mycologic challenges.

Targeting fungi: a challenge

Invasive fungal infections are more commonly identified in various categories of patients, mainly in cancer patients but also in those undergoing organ transplantation, patients in intensive care units, and those with AIDS. There is a great need to increase the awareness of practitioners who are still underestimating the morbidity and mortality relating to invasive fungal infections, and to stress the economic burden for the society and healthcare systems of invasive fungal infections. The list of fungal pathogens causing life-threatening complications has also increased recently, with the emergence of unusual fungi being more frequently identified in such settings. Early diagnosis of invasive fungal infections is still a major challenge for the clinician at the bedside. Identification of state-of-the-art management is also a difficult task for the clinical scientist involved in the assessment of optimal strategies to prevent and to treat those invasive fungal infections, although major progress has occurred in the last 5 years with the development of new, safe, and effective antifungal agents. Empiric therapy remains a very controversial issue that should be further investigated in high-quality clinical trials. Overall, clinical research in this difficult field requires independent and objective analysis; only large multicenter clinical trials can address these critical issues and rapidly provide convincing results leading to a better prognosis of patients with invasive fungal infections. These complications still represent too often an obstacle to successful control of severe underlying diseases. Clinical research on the appropriate ways to target fungi will not only define state-of-the-art management but also identify ineffective or redundant treatments. Such an approach will make a substantial contribution to the care of the high-risk patients within the next decade and will preserve our capacity for medical excellence.

Prevention and therapy of fungal infections in cancer patients. A review of recently published information

This review of recent publications in the field of fungal infections in cancer patients clearly confirms that protracted severe granulocytopenia is a major risk factor for their development. Because severe and prolonged granulocytopenia plays such a major predisposing role for fungal infections, it is likely that the use of the colony-stimulating factors, which are able to reduce the duration and the severity of granulocytopenia, might prove effective in decreasing the frequency and the severity of these infections. Another conclusion is that certain categories of patients with granulocytopenia might benefit from antifungal prophylaxis and empiric therapy. Conversely, there are other populations who will benefit only marginally from such strategies. Imidazoles, namely fluconazole, for the prevention of local and systemic Candida infections have been shown to be effective in granulocytopenic patients. So far, the development of resistance has not been a major problem. In patients at the greatest risk of developing severe fungal infections, such as those receiving high-dose corticosteroid therapy for GVHD after allogeneic bone marrow transplantation, early administration of low doses of amphotericin B seems to be effective in reducing the development of systemic fungal infection. In terms of therapy, amphotericin B is still the standard approach, especially for empiric treatment, prior to the recognition of a specific pathogen.