Invasive aspergillosis. Disease spectrum, treatment practices, and outcomes. I3 Aspergillus Study Group

Treatment of opportunistic mycoses: how long is long enough?

For most opportunistic mycoses no optimum duration of antifungal therapy has been defined. Although a long course of therapy is prudent, especially for mycelial fungal infections, excessively and unnecessarily extended courses of treatment incur a risk of toxicity and the expense of the therapeutic regimen. On the basis of existing reports on the pathogenesis and the effect of duration of therapy and other variables on outcome and response rate in fungal infections, this review proposes guidelines that may facilitate a rational approach to decision-making about the duration of antifungal therapy.

Systemic Antifungal Therapy: New Options, New Challenges

The frequency of invasive fungal infections has increased dramatically in recent decades because of an expanding population at risk. Until now, treatment options for invasive mycoses have been primarily amphotericin B and the azoles, fluconazole and itraconazole. Traditional agents are limited by an inadequate spectrum of activity, drug resistance, toxicities, and drug-drug interactions. The recent approval of caspofungin and voriconazole clearly has expanded the number of existing antifungal drugs available. However, the enthusiasm that accompanies their availability is counterbalanced by limited clinical experience, high drug acquisition costs, and distinctive toxicities. The pharmacologic characteristics, extent of clinical experience (efficacy and toxicity), and drug acquisition costs among available systemic antifungal agents are compared, with emphasis on the new agents. Also, recommendations on the role of each agent are provided according to the most common indications for systemic antifungal therapy: invasive candidiasis, invasive aspergillosis, and febrile neutropenia.

Combination chemotherapy for invasive fungal infections: what laboratory and clinical studies tell us so far

Despite potential benefits, few objective clinical data (with the exception of cryptococcocal meningitis) are available supporting the routine use of combination antifungal regimens in patients with invasive mycoses, importantly aspergillosis or candidiasis. There is considerable debate on what constitutes synergy or antagonism in vitro and whether these laboratory findings are translated to beneficial interactions in patients. Given the lack of rigorous clinical data, a better understanding of the important concepts for the justification of the clinical and pharmacoeconomic threshold of antifungal therapy is needed. Such concepts include standardized methods for screening antifungal combinations in culture or in animals and collaborative efforts to collect clinical data on the efficacy and safety of combination regimens.

Outbreak of invasive Aspergillus infection in surgical patients, associated with a contaminated air-handling system

An outbreak of Aspergillus infection at a tertiary care hospital was identified among inpatients who had amputation wounds, peritonitis, allograft nephritis, or mediastinitis. During a 2-year period, 6 patients were identified, all of whom had Aspergillus species recovered from samples from normally sterile sites. All cases clustered in the operating theater during a single 12-day period. To assess operating theater air quality, particle counts were measured as surrogate markers for Aspergillus conidia. A substantial increase in the proportion of airborne particles > or =3 microm in size (range, 3-fold to 1000-fold) was observed in many operating rooms. A confined space video camera identified moisture and contamination of insulating material in ductwork and variable airflow volume units downstream of final filters. No additional invasive Aspergillus wound infections were identified after the operating theater air-handling systems were remediated, suggesting that this unusual outbreak was due to the deterioration of insulating material in variable airflow volume units.

Benefit of surgical resection of invasive pulmonary aspergillosis in pediatric patients undergoing treatment for malignancies and immunodeficiency syndromes

PURPOSE

The aim of this study was to evaluate the outcome of children undergoing treatment for malignancy and immunodeficiency syndromes in whom invasive pulmonary aspergillosis (IPA) developed.

METHODS

The authors reviewed the medical records of all patients treated at their institution from January 1990 to August 1999 for culture-proven pulmonary aspergillus infection.

RESULTS

Among the 43 patients studied, the median age at the time of diagnosis of IPA was 13.1 years. The most common primary diagnoses were acute myelogenous leukemia (n = 18) and acute lymphoblastic leukemia (n = 14); 27 patients (63%) had received a bone marrow transplant (BMT). Of the 18 patients who underwent surgical intervention for IPA, 14 (78%) had one operation, whereas the remaining 4 patients had 2. The 4 patients alive at the time this report was written had undergone surgical intervention 2, 10, 23, and 44 months previously respectively. Surgical resection of the involved lung parenchyma was significantly prognostic for survival (P <.001). Other factors that influenced outcome were the extent of pulmonary invasion, steroid use, and the timing of bone marrow transplantation (BMT) in regard to the diagnosis of IPA.

CONCLUSIONS

The overall mortality rate of children treated for malignancies and immunodeficiency syndromes in who IPA develops remains high, and antifungal therapy alone may not be curative. Surgical resection may provide a small but possibly the only chance for survival. Therefore, we would advocate for resection of all involved tissue, even if it requires reoperation.

Voriconazole concentrations in the cerebrospinal fluid and brain tissue of guinea pigs and immunocompromised patients

We characterized voriconazole concentrations in the cerebrospinal fluid (CSF) of immunocompetent guinea pigs and patients with invasive fungal infections. In animals, after receipt of oral doses of 4 or 10 mg/kg every 8 h, the mean ratios of CSF to plasma total and free drug concentration were 0.68 and 1.3, respectively. In humans, 1-10 h after receipt of voriconazole, the CSF concentrations ranged from 0.08 to 3.93 microg/mL, and the ratio of CSF to plasma concentration ranged from 0.22 to 1.0 (median, 0.46).

Amphotericin B: time for a new "gold standard"

When introduced in 1959, amphotericin B deoxycholate (AmBD) was clearly a life-saving drug. Randomized studies demonstrating its efficacy were not thought to be necessary, and it was granted indications for many invasive fungal infections. Despite its formidable toxicities, AmBD is thus often used as the primary comparator in studies of invasive fungal infections. Safer lipid-based versions of amphotericin B (AmB) have been introduced, but difficulties with studying these agents generally led to licensure for salvage therapy, not primary therapy. However, the cumulative clinical experience to date with the lipid-based preparations is now adequate to demonstrate that these agents are no less active than AmBD, and, for some infections, it can now be stated that specific lipid-based preparations of AmB are superior to AmBD. Given their superior safety profiles, these preparations can now be considered suitable replacements for AmBD for primary therapy for many invasive fungal infections in clinical practice and research.

Outcome predictors of 84 patients with hematologic malignancies and Fusarium infection

BACKGROUND

Invasive infection by Fusarium sp. is associated with high mortality in patients with hematologic cancer. Yet to the authors' knowledge, little is known regarding predictors of adverse outcome.

METHODS

The authors conducted a retrospective review of the records of patients with hematologic carcinoma and invasive fusariosis who were treated at one institution in the U.S. and at 11 centers in Brazil.

RESULTS

The records of 84 patients were evaluated. Neutropenia was present in 83% and 33 patients had undergone stem cell transplantation. Only 18 patients (21%) were alive 90 days after the diagnosis of fusariosis. Multivariate predictors of poor outcome were persistent neutropenia (hazard ratio [HR] of 5.43; 95% confidence interval [95% CI], 2.64-11.11) and use of corticosteroids (HR of 2.18; 95% CI, 1.98-3.96). The actuarial survival rate of patients without any of these factors was 67% compared with 30% for patients who recovered from neutropenia but were receiving corticosteroids and 4% for patients with persistent neutropenia only. None of the patients with both risk factors survived (P<0.0001).

CONCLUSIONS

Measures to reduce the duration of neutropenia, as well as the judicious use of corticosteroids, may reduce the high mortality rate of fusariosis in patients with hematologic cancer.

Efficacy and toxicity of caspofungin in combination with liposomal amphotericin B as primary or salvage treatment of invasive aspergillosis in patients with hematologic malignancies

BACKGROUND

Caspofungin (CAS) as salvage therapy for refractory invasive aspergillosis (IA) had a response rate of 45% among a heterogeneous group of patients. The use of CAS with other agents is appealing given its unique mechanism of action. Therefore, the authors retrospectively evaluated the efficacy and toxicity of CAS plus liposomal amphotericin B (LipoAMB) in patients with documented (definite or probable) or possible IA.

METHODS

Patients were evaluable for outcome if they received CAS/LipoAMB for at least 7 days. Patients who received CAS and LipoAMB sequentially were excluded. All patients were evaluable for toxicity. Outcome was assessed weekly and at the end of therapy. Stable disease and progression were considered treatment failures.

RESULTS

Forty-eight patients with documented (n=23) or possible (n=25) IA were identified between March 2001 and December 2001. The majority of the patients (65%) received CAS/LipoAMB as salvage therapy for progressive IA despite 7 or more days of previous LipoAMB monotherapy. The overall response rate was 42%. No significant toxic effects were seen. Factors associated with failure at the end of therapy were documented IA (P=0.03), significant steroid use before the study (P=0.02), and duration of combination therapy for less than 14 days (P=0.01). The response rate in patients with progressive documented IA was low (18%).

CONCLUSIONS

The CAS/LipoAMB combination is a promising preemptive therapy for IA and was generally well tolerated. This combination might have limited benefit as salvage therapy for documented IA.

Invasive aspergillosis in liver transplant recipients: outcome comparison of therapy with amphotericin B lipid complex and a historical cohort treated with conventional amphotericin B

Invasive aspergillosis (IA) in liver transplant recipients is associated with poor response rates and a very high mortality rate, despite administration of therapy with conventional amphotericin B. We conducted a single-center, retrospective study to compare the outcome of liver transplant recipients with IA who received amphotericin B lipid complex (ABLC) or conventional amphotericin B. IA was present in 12 ABLC-treated patients (definite, 4; probable, 8) and 29 amphotericin B recipients (definite, 11; probable, 18) in the historical cohort. The 60-day mortality rate was lower in the ABLC cohort: 4 (33%) of 12 patients versus 24 (83%) of 29 patients (P=.006). Only 1 of 4 ABLC recipients with definite IA died, compared with all 11 in the amphotericin B group. Sixty-day survival probability curves was significantly lower in the amphotericin B cohort (P=.008). ABLC therapy was the only independent mortality-protective variable (odds ratio, 0.31; 95% confidence interval, 0.07-0.44; P=.02). First-line or early salvage therapy for IA with ABLC was associated with significantly improved survival relative to a comparable historical group treated with amphotericin B.

Caspofungin in the treatment of candidosis and aspergillosis

Antifungal agents can be classified by their site of action in fungal cells, which can have important implications for both efficacy and tolerability. Currently available agents include the polyenes, nucleoside analogs, and the azoles. With the exception of 5-fluorocytosine, all agents act by interfering with the structural or functional integrity of the fungal plasma membrane. However, the non-selective nature of this therapeutic target results in concomitant cross-inhibition (or toxicity) in mammalian cells. New compounds that interfere with the fungal cell wall--a target not present in mammalian cells--therefore constitute an important focus of current clinical research. Caspofungin, the first representative of a new class of antifungals that inhibit beta-(1,3)-D-glucan synthesis, exerts potent activity against Candida and Aspergillus spp. and appears to be generally well tolerated. This paper reviews the data on caspofungin.

Fungal pneumonias in transplant recipients

Fungi are ubiquitous in the environment. Opportunistic fungal pneumonias in the immunocompromised host continue to increase most commonly due to Aspergillus sp. Affected patients are usually hematopoietic stem cell and lung transplant recipients. Clinical presentation is protean, and the diagnosis is challenging. Culture of respiratory specimens has limited utility. The detection of circulating fungal antigens and DNA seems promising, but more studies are needed. Value of prophylactic strategies or preemptive therapy remains contentious. New antifungal drugs for managing invasive pulmonary aspergillosis continue to emerge, with better safety, efficacy, and pharmacologic profiles.

Voriconazole treatment for less-common, emerging, or refractory fungal infections

Treatments for invasive fungal infections remain unsatisfactory. We evaluated the efficacy, tolerability, and safety of voriconazole as salvage treatment for 273 patients with refractory and intolerant-to-treatment fungal infections and as primary treatment for 28 patients with infections for which there is no approved therapy. Voriconazole was associated with satisfactory global responses in 50% of the overall cohort; specifically, successful outcomes were observed in 47% of patients whose infections failed to respond to previous antifungal therapy and in 68% of patients whose infections have no approved antifungal therapy. In this population at high risk for treatment failure, the efficacy rates for voriconazole were 43.7% for aspergillosis, 57.5% for candidiasis, 38.9% for cryptococcosis, 45.5% for fusariosis, and 30% for scedosporiosis. Voriconazole was well tolerated, and treatment-related discontinuations of therapy or dose reductions occurred for <10% of patients. Voriconazole is an effective and well-tolerated treatment for refractory or less-common invasive fungal infections.

Prolonged survival after invasive aspergillosis: a single-institution review of 11 cases

PURPOSE

To perform a retrospective review of the authors' experience with invasive aspergillosis (IA) in a pediatric population treated with conventional chemotherapy. Case series of IA in the pediatric oncology population are limited but generally report poor overall survival.

METHODS

Medical records were reviewed of all patients receiving conventional chemotherapy for malignant disease who developed IA at Children's Hospital and Regional Medical Center, Seattle, Washington, between January 1, 1995, and January 1, 2002.

RESULTS

During the study period there were 11 cases of IA in pediatric cancer patients treated with conventional chemotherapy. All patients had pulmonary IA; two also had evidence of disseminated disease. All patients underwent diagnostic tissue biopsy. Sixty-four percent required further surgery to excise bulky disease. Medical therapy varied with disease presentation and the overall clinical picture, although prolonged treatment with amphotericin B and itraconazole was the mainstay of therapy. Resolution of clinical disease was seen in 91% of patients. Seventy-three percent received further chemotherapy. The 3-year estimated survival was 82%, with a median follow-up of 32.5 months.

CONCLUSIONS

Early diagnosis and aggressive intervention improve long-term survival from IA in immunocompromised pediatric oncology patients. Aggressive surgical resection, prolonged medical therapy after gross resolution of disease, and chemoprophylaxis during subsequent chemotherapy decrease the likelihood of recurrent IA despite subsequent cytotoxic therapy. The ability to proceed with intensive chemotherapy despite a history of IA may improve long-term survival.

The role of muscle flaps in pulmonary aspergillosis

Pulmonary invades the lung parenchyma and vessels, causing necrotizing pneumonia and massive hemoptysis in immunocompromised patients. Medical treatment alone often fails to clear the organism. Early surgical intervention is advocated in localized disease to remove infection near pulmonary vessels. The resection is limited in an attempt to preserve as much lung function as possible. However, preexisting cavitations and lung disease predispose to postoperative space problems, including prolonged air leak, bronchopleural fistula, and empyema. Muscle flaps provide a solution to these problems by obliterating residual space and providing protective coverage to the bronchial stump. The authors present four cases of pulmonary aspergillosis treated by multimodality therapy and extrathoracic muscle flap transposition. Factors that may contribute to successful treatment include underlying condition of the host and history of cancer, radiation therapy, and great vessel involvement. Despite aggressive medical and surgical therapy, pulmonary aspergillosis has a poor prognosis.

In vitro susceptibility testing of Aspergillus spp.: comparison of Etest and reference microdilution methods for determining voriconazole and itraconazole MICs

The performance of the Etest for voriconazole and for itraconazole susceptibility testing of 376 isolates of Aspergillus spp. was assessed in comparison with the National Committee for Clinical Laboratory Standards (NCCLS) proposed standard microdilution broth method. The NCCLS method employed RPMI 1640 broth medium, and MICs were read after incubation for 48 h at 35 degrees C. Etest MICs were determined with RPMI agar containing 2% glucose and were read after incubation for 48 h at 35 degrees C. The isolates included A. fumigatus, A. flavus, A. niger, A. terreus, A. versicolor, A. glaucus, A. nidulans, A. ustus, and A. sydowii. Overall agreement percentages between the Etest and microdilution MICs were 97.6% for voriconazole and 95.8% for itraconazole. Where a discrepancy was observed between Etest and the reference method, the Etest tended to give lower values with voriconazole and higher values with itraconazole. The Etest method using RPMI agar appears to be a useful method for determining the voriconazole and itraconazole susceptibilities of Aspergillus spp.

Successful treatment of invasive aspergillosis in two patients with acute myelogenous leukemia

Invasive aspergillosis is a severe, devastating fungal infection that is seen in patients with hematologic malignancies and profound neutropenia. Despite aggressive treatment, the outcome is poor without neutrophil recovery. The authors describe two children with acute myelogenous leukemia (AML) with extensive invasive aspergillosis who were successfully treated both for their infection and the underlying malignancy. These patients were treated aggressively for their infections and simultaneously were able to complete treatment of their AML. Currently both patients are alive without evidence of fungal infection or AML. Patients with hematologic malignancies can survive severe, invasive aspergillosis during prolonged periods of neutropenia with a combination of antifungal and growth factor therapies, donor granulocyte infusions, and surgical debridement.

The isolation of Aspergillus fumigatus from respiratory tract specimens in heart transplant recipients is highly predictive of invasive aspergillosis

BACKGROUND

Prompt recognition of invasive pulmonary aspergillosis (IPA) after heart transplantation is essential for achieving a successful outcome. However, the significance of the isolation of from respiratory specimens in heart transplant recipients is not established.

METHODS

From 1990 to 1999, we analyzed first respiratory specimens with spp. growth from heart transplant patients in our institution. All specimens were cultured in both fungal and conventional media. Diagnosis of proven and probable IPA or colonization was made according to criteria of the Mycoses Study Group.

RESULTS

During the 10-year study period, spp. was recovered from 30 episodes from 27 heart transplant recipients (incidence: 10.5%). Three episodes were classified as indeterminate and were included in the analysis in a double way, first considering them as true positives and afterward as true negatives, so ranges were obtained. After applying diagnostic criteria, 18 of 30 episodes were proven or probable IPA, and 9 episodes were colonizations. Accordingly, 7 to 8% of heart transplant recipients suffered an IPA, and the overall positive predictive value (PPV) was 60% to 70%. When analyzed by species, the PPV of recovering was 78% to 91%, whereas it was 0% for other species. The PPV increased to 88% to 100% when was recovered from a respiratory specimen other than sputum and decreased to 50% to 67% when it was recovered from sputum. The sensitivities of fungal and conventional media for the recovery of spp. were 95% to 100% and 33% to 38%, respectively.

CONCLUSION

The isolation of from the respiratory tract of a heart transplant recipient is highly predictive of invasive aspergillosis.

Pseudomembranous tracheobronchial aspergillosis: a rare manifestation of invasive aspergillosis in a non-neutropenic patient with Hodgkin's disease

Pseudomembranous tracheobronchial aspergillosis coincident with systemic pulmonary aspergillosis represents a rare manifestation of fungal infection in immunocompromized hosts. We report on a patient with recurrent Hodgkin's disease, showing this infectious pattern after treatment with corticosteroids within the antineoplastic schedule, whereas neutropenia--the main risk factor for mold infections--had not occurred. An impaired number of helper T lymphocytes was merely detected as an additional, but hypothetical risk factor, when investigating the status of immunosuppression. Treated systemically with amphotericin B, the patient recovered quickly, although reported mortality rates are disastrous. What is crucial for the clinical management is an early diagnosis by bronchoscopy and cultural proof of the pathogen followed by an adequate antifungal treatment.

Central nervous system aspergillosis in allogeneic stem cell transplant recipients

Invasive aspergillosis (IA) is relatively common in allogeneic stem cell transplant (SCT) recipients. Although lungs are the most common site, central nervous system (CNS) involvement is also observed in this setting. We have retrospectively studied 14 cases of CNS aspergillosis found in a cohort of 455 allogeneic SCT recipients (incidence 3%). All patients, except one, had experienced acute graft-versus-host disease treated with high-dose methylprednisolone, and eight patients (57%) had also received ATG. The median time to the diagnosis of CNS aspergillosis was 124 days (range 49-347 days) from SCT. Pulmonary aspergillosis had been diagnosed earlier in four patients (29%). The most common initial symptoms of CNS aspergillosis were convulsions, hemiparesis, and mental alteration. Neuroradiological studies revealed single (two patients) or multiple (seven patients) focal lesions of 0.2-9 cm in diameter. Despite clinical suspicion in many patients, a confirmed diagnosis of CNS aspergillosis was made during life in only one patient. A total of 12 patients (86%) received amphotericin B. Despite therapy, all patients died 0-27 days (median seven days) after the initial CNS symptoms. CNS aspergillosis is not uncommon in allogeneic SCT recipients. Clinical manifestations are usually dramatic and progress quickly. Earlier and more effective treatment of IA is needed to prevent dissemination of infection into the CNS.

In vitro activity of voriconazole, itraconazole, caspofungin, anidulafungin (VER002, LY303366) and amphotericin B against aspergillus spp

Voriconazole, anidulafungin (VER002, LY303366) and caspofungin are promising antifungal agents which provide a good protection against a variety of fungi, including yeasts and filamentous fungi. In this study, we tested the in vitro efficacy of voriconazole, itraconazole, caspofungin, anidulafungin (VER002, LY303366) and amphotericin B, against different species of Aspergillus spp. isolated from clinical specimens, using a microdilution broth method and following the NCCLS guidelines (document M38-P). We also evaluated the effect that time readings have on MIC results. For caspofungin, we determined the minimun effective concentration (MEC), defined like the lowest concentration of caspofungin causing abnormal hyphal growth. Anidulafungin (VER002, LY303366) was the most active antifungal agent tested with MIC(90) of < or =0,03 mg/L. The activity of voriconazole, and itraconazole very similar with MIC(90) of 0,12 mg/L, 0,12 mg/L respectively. For caspofungin the MEC(90) was of 0,25 mg/L. Amphotericin B was the lest active antifungal agent studied with MIC(90) of 1 mg/L. There were no differences between MIC values at 48 and 72 h. These data demonstrate promising activity of voriconazole, anidulafungin (VER002, LY303366) and caspofungin against Apergillus spp.

Antifúngicos de uso sistémico

Invasive fungal infection is the infectious complication with highest associated mortality. Until the 90's amphotericin B was the only drug available to treat these infections. Its spectrum of antifungal activity is excellent, but its use is associated with toxicity in many cases. The development of amphotericin B lipid formulations has resulted in a significant decrease in most of the side effects associated with this drug. Triazoles are safe and effective for treating most invasive fungal infections. Fluconazole is an excellent drug for the prevention and treatment of Candida and Cryptococcus infections, itraconazole has good activity against Candida and Aspergillus, and voriconazole has shown to be better than amphotericin B for invasive aspergillosis. Caspofungin belongs to a new group of antifungal agents, the echinocandins, which are very safe and present excellent activity against Candida and Aspergillus.

Aspergillosis. Pathogenesis, clinical manifestations, and therapy

Diseases caused by Aspergillus species are increasing in importance, especially among immunocompromised hosts. Clinical manifestations are variable, ranging from allergic to invasive disease, largely depending on the status of the host's immune system. This article focuses on the pathogenesis and clinical manifestations of diseases caused by Aspergillus species, with more detailed discussion on therapy of the most morbid manifestation, invasive aspergillosis.

Environmental surveillance of filamentous fungi in three tertiary care hospitals in Greece

The environmental fungal load (FL) of three hospitals was studied in representative regions in Greece (Thessalonika, Northern Greece, Athens, Central Greece and Heraklion, Southern Greece). Air, surfaces and tap water from high-risk departments were sampled monthly during one year. Air FL was [median (range)] 10.6 (1.2-37), 5.5 (3-28.8) and 7.7 (3.1-12.1) cfu/m(3) at Thessalonika, Athens and Heraklion, respectively. Air FL was lower in winter and higher in summer and autumn but seldom above acceptable levels. Aspergillus spp. constituted 70.5% of the filamentous fungi isolated. Aspergillus niger was the most prevalent species in the air of all the hospitals followed by Aspergillus flavus and Aspergillus fumigatus. The least contaminated departments were the intensive care units, whilst most contaminated were the solid organ transplantation in Athens and haematology departments in Thessalonika. No correlation between fungal species, season, hospital or departments was observed. Sixty per cent of all surfaces examined yielded filamentous fungi and/or blastomycetes. While no fungi were recovered from water in Thessalonika and Athens, one-third of the samples in Heraklion (apart from those of ICU) yielded multiple fungal species. The higher air FL in Thessalonika and Athens was recorded in departments located close to renovation works. These findings suggest that the air and surface FL fluctuates over the year, is due to varying fungal species, but does not differ greatly among hospitals. The variation among hospitals, as well as the role of hospital water fungal contamination and appropriate measures to eliminate it, need further study.

Antifungal resistance in pathogenic fungi

Pathogenic fungi are the cause of life-threatening infections in an increasing number of immunocompromised patients. The intrinsic resistance to antifungal therapy observed in some genera, along with the development of resistance during treatment in others, is becoming a major problem in the management of these diseases. We reviewed the epidemiology of the most common systemic fungal infections for which antifungal resistance is a potential problem, the mechanisms of antifungal resistance, the correlation between in vitro susceptibility testing and clinical outcome, and the clinical implications of antifungal resistance.

In vitro interaction of caspofungin acetate with voriconazole against clinical isolates of Aspergillus spp

The interaction between caspofungin acetate and voriconazole was studied in vitro by using 48 clinical Aspergillus spp. isolates obtained from patients with invasive aspergillosis. MICs were determined by the NCCLS broth microdilution method. Synergy, defined as a fractional inhibitory concentration (FIC) index of <1, was detected in 87.5% of the interactions; an additive effect, defined as an FIC index of 1.0, was observed in 4.2% of the interactions; and a subadditive effect, defined as an FIC index of 1.0 to 2.0, was found in 8.3% of the interactions. No antagonism was observed. Animal models are required to validate the in vivo significance of these in vitro data presented for the combination of caspofungin and voriconazole.

Voriconazole versus amphotericin B for primary therapy of invasive aspergillosis

BACKGROUND

Voriconazole is a broad-spectrum triazole that is active against aspergillus species. We conducted a randomized trial to compare voriconazole with amphotericin B for primary therapy of invasive aspergillosis.

METHODS

In this randomized, unblinded trial, patients received either intravenous voriconazole (two doses of 6 mg per kilogram of body weight on day 1, then 4 mg per kilogram twice daily for at least seven days) followed by 200 mg orally twice daily or intravenous amphotericin B deoxycholate (1 to 1.5 mg per kilogram per day). Other licensed antifungal treatments were allowed if the initial therapy failed or if the patient had an intolerance to the first drug used. A complete or partial response was considered to be a successful outcome.

RESULTS

A total of 144 patients in the voriconazole group and 133 patients in the amphotericin B group with definite or probable aspergillosis received at least one dose of treatment. In most of the patients, the underlying condition was allogeneic hematopoietic-cell transplantation, acute leukemia, or other hematologic diseases. At week 12, there were successful outcomes in 52.8 percent of the patients in the voriconazole group (complete responses in 20.8 percent and partial responses in 31.9 percent) and 31.6 percent of those in the amphotericin B group (complete responses in 16.5 percent and partial responses in 15.0 percent; absolute difference, 21.2 percentage points; 95 percent confidence interval, 10.4 to 32.9). The survival rate at 12 weeks was 70.8 percent in the voriconazole group and 57.9 percent in the amphotericin B group (hazard ratio, 0.59; 95 percent confidence interval, 0.40 to 0.88). Voriconazole-treated patients had significantly fewer severe drug-related adverse events, but transient visual disturbances were common with voriconazole (occurring in 44.8 percent of patients).

CONCLUSIONS

In patients with invasive aspergillosis, initial therapy with voriconazole led to better responses and improved survival and resulted in fewer severe side effects than the standard approach of initial therapy with amphotericin B.

Efficacy of caspofungin alone and in combination with voriconazole in a Guinea pig model of invasive aspergillosis

The antifungal activity of caspofungin acetate (CAS) alone and in combination with voriconazole (VRC) was evaluated in an immunosuppressed transiently neutropenic guinea pig model of invasive aspergillosis. Guinea pigs were immunosuppressed with triamcinolone at 20 mg/kg of body weight/day subcutaneously beginning 4 days prior to lethal intravenous challenge with Aspergillus fumigatus and were made temporarily neutropenic with cyclophosphamide administered at 150 mg/kg intraperitoneally (i.p.) 1 day prior to challenge. Therapy with i.p. CAS at 1 and 2.5 mg/kg/day (with and without oral VRC at 5 mg/kg/day), oral VRC at 5 mg/kg/day, or i.p. amphotericin B (AMB) at 1.25 mg/kg/day was begun 24 h after challenge and was continued for 5 days. Mortality occurred in 12 of 12 untreated controls, whereas mortality occurred in 4 of 12 and 6 of 12 guinea pigs treated with CAS at 1 and 2.5 mg/kg/day, respectively, and in 3 of 12 guinea pigs treated with AMB. No mortality occurred among animals treated with CAS at 1 mg/kg/day plus VRC at 5 mg/kg/day, CAS at 2.5 mg/kg/day plus VRC at 5 mg/kg/day, or VRC at 5 mg/kg/day alone. Both CAS regimens increased the survival times and reduced the colony counts in tissue compared with those for the controls. Treatment with VRC and AMB significantly reduced the colony counts in the tissues of selected animals compared with those in the tissues of the controls. Treatment with VRC and AMB also resulted in reductions in colony counts in tissues compared with those in the tissues of animals treated with CAS (the difference was not statistically significant) and improved the survival times but did not sterilize tissues. Combination therapies with CAS plus VRC at either dose reduced colony counts in tissues 1,000-fold over those for the controls and were the only regimens that significantly reduced the numbers of positive cultures. The combinations of CAS plus VRC were highly effective in this model and should be further evaluated for use against invasive aspergillosis.

Invasive fungal infection in patients with myelodysplastic syndrome: a report of twelve cases

In this report we analyse the risk factors, clinical characteristics and outcome of patients with myelodysplastic syndrome (MDS) who developed a invasive fungal infection (IFI). This was a multicentric study involving 14 Italian Haematological Divisions during a 10-year-period whose object was to identify the characteristics of patients with this infection. The study recorded 391 consecutive documented IF, 12 of which (3%) occurred in MDS patients from five of the participating centres. The primary localisation of infection was the lung in 10 cases and skin and paranasal sinus in one case each. Ten patients died at the end of the follow up. The death was mainly attributable to IFI progression in nine of them. The factors which appeared related to an unfavourable outcome were intensive chemotherapy within 30 days before IFI diagnosis, presence of multiple localisation at chest X-ray in patients with isolated pulmonary IFI and multiple sites of infection.

Epidemiology of invasive aspergillosis in France: a six-year multicentric survey in the Greater Paris area

Invasive aspergillosis is the most prevalent mould infection. An epidemiological surveillance network was set up in 18 teaching hospitals in Paris and the Greater Paris area. Prospective surveillance was conducted between 1994 and 1999. Between 1994 and 1997 cases were categorized as proven or probable aspergillosis and then the European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria were used. The authors analysed 621 cases (115 proven, 506 probable). No seasonal variation was found. Haematological disorders (73%) including stem-cell transplantation (36%), solid-organ transplantations (10%) and AIDS (9%) were the main underlying conditions. The crude mortality was 63%. Incidence of IA was 8% (CI(95): 6.5-9.5) in acute myelocytic leukaemia and 6.3% (CI(95): 4.3-8.3) in acute lymphocytic leukaemia. Incidence was 12.8% (CI(95): 10.8-14.8) following allogeneic stem-cell transplantation and 1.1% (CI(95): 0.7-1.5) following autologous stem-cell transplantation. In solid-organ recipients incidence ranged from 11% following heart-lung transplantation and small bowel to 0.4% following kidney transplantation. Incidence in HIV infected patients ranged from 0.02 to 0.13% per annum. This large series confirmed that patients with haematologic disorders and transplantations are the most at risk for IA.

A review of nucleic acid-based diagnostic tests for systemic mycoses with an emphasis on polymerase chain reaction-based assays

Nucleic acid-based assays have good potential to complement and enhance the sensitivity and rapidity of conventional methods used in diagnostic mycology. The majority of molecular tests are polymerase chain reaction (PCR)-based assays focusing mainly on the detection of Candida and Aspergillus spp. from clinical samples. DNA extraction and purification procedures should be standardized and can be facilitated by using commercial extraction kits. In general, protocols that target multi-copy genes provide the greatest sensitivity. Objective endpoint assessments of PCR tests using enzyme-linked immunosorbent assays (ELISA) or commercial quantitative systems are capable of rapidly detecting and identifying Candida and Aspergillus spp. Sequencing of PCR products can be used to confirm the identity of amplicons. In cases of suspected invasive aspergillosis, PCR should be performed on both blood and bronchoalveolar lavage fluid to maximize test sensitivity and the positive predictive value. At least two blood specimens should be tested if PCR is undertaken on blood samples alone. In situ hybridization techniques have been used with success to identify fungi in tissue specimens. The wide application of PCR-based assays relies on the introduction of standardized protocols following their evaluation in multicentre, prospective studies.

Infections in the neutropenic patient--new views of an old problem

Infection in the neutropenic patient has remained a major clinical challenge for over three decades. While diagnostic and therapeutic interventions have improved greatly during this period, increases in the number of patients with neutropenia, changes in the etiologic agents involved, and growing antibiotic resistance have continued to be problematic. The evolving etiology of infections in this patient population is reviewed by Dr. Donowitz. Presently accepted antibiotic regimens and practices are discussed, along with ongoing controversies. In Section II, Drs. Maki and Crnich discuss line-related infection, which is a major infectious source in the neutropenic. Defining true line-related bloodstream infection remains a challenge despite the fact that various methods to do so exist. Means of prevention of line related infection, diagnosis, and therapy are reviewed. Fungal infection continues to perplex the infectious disease clinician and hematologist/oncologist. Diagnosis is difficult, and many fungal infections will lead to increased mortality even with rapid diagnosis and therapy. In Section III, Dr. Pappas reviews the major fungal etiologies of infection in the neutropenic patient and the new anti-fungals that are available to treat them. Finally, Dr. Rolston reviews the possibility of outpatient management of neutropenic fever. Recognizing that neutropenics represent a heterogeneous group of patients, identification of who can be treated as an outpatient and with what antibiotics are discussed.

Filamentous fungi infection in patients with myelodysplastic syndrome. A report of twelve cases

In this report we analyse the risk factors, the clinical characteristics and outcome of patients with myelodysplastic syndrome (MDS) who developed an Invasive Fungi Infection (IFI). This was a multicentric study involving 14 Italian Haematological Divisions during a 10-year period whose object was to identify the characteristics of patients with this infection. The study recorded 391 consecutive documented IFI, 12 of which (3%) occurred in MDS patients, from 5 of the participating centres. The primary localization of infection was lung in 10 cases and skin and paranasal sinus in 1 case each. Ten patients died at the end of follow up. The death was mainly attributable to IFI progression in nine of them. The factors that appeared related to an unfavourable outcome were intensive chemotherapy within 30 days before IFI diagnosis, presence of multiple localization at chest X-ray in patients with isolated pulmonary IFI and multiple sites of infection.

Nosocomial outbreak of Exophiala jeanselmei fungemia associated with contamination of hospital water

From December 1996 through September 1997, we diagnosed 19 cases of fungemia due to Exophiala jeanselmei. We conducted a matched case-control study in which we cultured specimens of blood products, intravenous solutions, and water from a hospital water system. Isolates from environmental cultures were compared to those recovered from patients by random amplification of polymorphic DNA (RAPD). Multivariate analysis showed that neutropenia, longer duration of hospitalization, and use of corticosteroids were risk factors for infection. Environmental cultures yielded E. jeanselmei from 3 of 85 sources: deionized water from the hospital pharmacy, 1 water tank, and water from a sink in a non-patient care area. Use of deionized pharmacy water to prepare antiseptic solutions was discontinued, and no additional cases of infection occurred. RAPD typing showed that isolates from case patients and isolates from the pharmacy water were highly related, whereas the patterns of isolates recovered from the 2 other sources of water were distinct.

RNA-mediated gene silencing in non-pathogenic and pathogenic fungi

Many fungal genomes have now been sequenced and thousands of genes are being discovered. Gene disruption or inactivation technology offers an important tool not only for elucidating the function of the many unknown genes but also for the identification of genes essential for fungal growth and pathogenesis. A variety of gene-silencing methods that inhibit genes at the post-transcriptional level are now being used in both non-pathogenic and human pathogenic fungi. We focus on the recent advances in RNA-mediated gene silencing technologies and their potential for functional genomics studies in fungi.

The clinical spectrum of pulmonary aspergillosis

Aspergillus is a ubiquitous fungus that causes a variety of clinical syndromes in the lung, ranging from aspergilloma in patients with lung cavities, to chronic necrotizing aspergillosis in those who are mildly immunocompromised or have chronic lung disease. Invasive pulmonary aspergillosis (IPA) is a severe and commonly fatal disease that is seen in immunocompromised patients, while allergic bronchopulmonary aspergillosis is a hypersensitivity reaction to Aspergillus antigens that mainly affects patients with asthma. In light of the increasing risk factors leading to IPA, such as organ transplantation and immunosuppressive therapy, and recent advances in the diagnosis and treatment of Aspergillus-related lung diseases, it is essential for clinicians to be familiar with the clinical presentation, diagnostic methods, and approach to management of the spectrum of pulmonary aspergillosis.

Pneumocystis carinii pneumonia in patients with malignant haematological diseases: 10 years' experience of infection in GIMEMA centres

A retrospective survey was conducted over a 10-year period (1990-99) among 52 haematology divisions in order to evaluate the clinical and laboratory characteristics and outcome of patients with proven Pneumocystis carinii pneumonia (PCP) complicating haematological diseases. The study included 55 patients (18 with non-Hodgkin's lymphoma, 10 with acute lymphoblastic leukaemia, eight with acute myeloid leukaemia, five with chronic myeloid leukaemia, four with chronic lymphocytic leukaemia, four with multiple myeloma, three with myelodysplastic syndrome, two with myelofibrosis and one with thalassemia) who developed PCP. Among these, 18 (33%) underwent stem cell transplantation; only two received an oral prophylaxis with trimethroprim/sulphamethoxazole. Twelve patients (22%) developed PCP despite protective isolation in a laminar airflow room. The most frequent symptoms were: fever (86%), dyspnoea (78%), non-productive cough (71%), thoracic pain (14%) and chills (5%); a severe hypoxaemia was present in 39 patients (71%). Chest radiography or computerized tomography showed interstitial infiltrates in 34 patients (62%), alveolar infiltrates in 12 patients (22%), and alveolar-interstitial infiltrates in nine patients (16%). Bronchoalveolar lavage was diagnostic in 47/48 patients, induced sputum in 9/18 patients and lung biopsy in 3/8 patients. The diagnosis was made in two patients at autopsy. All patients except one started a specific treatment (52 patients trimethroprim/sulphamethoxazole, one pentamidine and one dapsone). Sixteen patients (29%) died of PCP within 30 d of diagnosis. Multivariate analysis showed that prolonged steroid treatment (P < 0.006) and a radiological picture of diffuse lung involvement (P < 0.003) were negative diagnostic factors.

Voriconazole compared with liposomal amphotericin B for empirical antifungal therapy in patients with neutropenia and persistent fever

BACKGROUND

Patients with neutropenia and persistent fever are often treated empirically with amphotericin B or liposomal amphotericin B to prevent invasive fungal infections. Antifungal triazoles offer a potentially safer and effective alternative.

METHODS

In a randomized, international, multicenter trial, we compared voriconazole, a new second-generation triazole, with liposomal amphotericin B for empirical antifungal therapy.

RESULTS

A total of 837 patients (415 assigned to voriconazole and 422 to liposomal amphotericin B) were evaluated for success of treatment. The overall success rates were 26.0 percent with voriconazole and 30.6 percent with liposomal amphotericin B (95 percent confidence interval for the difference, -10.6 to 1.6 percentage points); these rates were independent of the administration of antifungal prophylaxis or the use of colony-stimulating factors. There were fewer documented breakthrough fungal infections in patients treated with voriconazole than in those treated with liposomal amphotericin B (8 [1.9 percent] vs. 21 [5.0 percent], P=0.02). The voriconazole group had fewer cases of severe infusion-related reactions (P<0.01) and of nephrotoxicity (P<0.001). The incidence of hepatotoxicity was similar in the two groups. Patients receiving voriconazole had more episodes of transient visual changes than those receiving liposomal amphotericin B (22 percent vs. 1 percent, P<0.001) and more hallucinations (4.3 percent vs. 0.5 percent, P<0.001). Parenteral voriconazole was changed to the oral formulation in 22 percent of the voriconazole group, with a reduction in the mean duration of hospitalization by one day in all patients (P=0.17) but by two days in patients at high risk (P=0.03).

CONCLUSIONS

Voriconazole is a suitable alternative to amphotericin B preparations for empirical antifungal therapy in patients with neutropenia and persistent fever.

Gastrointestinal infections in the immunocompromised host

Immunocompromised patients, including patients with AIDS, solid organ and bone marrow transplant recipients, patients with leukemia and lymphoma, patients with inherited immune deficiencies, and patients on immunosuppressive therapy for a variety of disorders, are at risk for infections-particularly opportunistic infections, which, by definition, do not infect the healthy host. All systems of the body, including the gastrointestinal tract, are susceptible. The esophagus, stomach, small intestine, and large intestine are sites of infection for viruses, bacteria, fungi, and protozoa. Symptoms can range in severity from fevers of unknown etiology to life-threatening hemorrhage and perforation. This review summarizes recent case reports, clinical studies, and reviews pertaining to pathogens that uniquely cause disease, more frequently cause disease, or cause more severe disease in the immunocompromised host than in the immunocompetent host.

Follow-up of anti-Aspergillus IgG and IgA antibodies in bone marrow transplanted patients with invasive aspergillosis

A total of 89 patients at risk for, or with invasive aspergillosis (IA) were recruited from bone marrow transplantation (BMT) units in two Lisbon hospitals, and followed for 2(1/2) years to monitor their immune response. Of these patients, six developed probable IA, from which five died. The presence of serum IgG or IgA antibodies against seven Aspergillus recombinant antigens was assessed in patients with IA, using an enzyme-linked immunosorbent assay (ELISA). In parallel, the serum levels of galactomannan (GM) were also monitored, using the Platelia Aspergillus kit (Sanofi Pasteur, Marnes-la-Coquette, France). Superoxide dismutase (Sod) and 94 kDa were the most immunogenic antigens for IgA, while the IgG pattern of recognition changed from patient to patient. From our results we conclude that although follow-up of antibodies against these antigens should not be used as a diagnostic method, patients with IA do produce an immune response that may influence disease outcome.

Antifungal efficacy of caspofungin (MK-0991) in experimental pulmonary aspergillosis in persistently neutropenic rabbits: pharmacokinetics, drug disposition, and relationship to galactomannan antigenemia

The antifungal efficacy, pharmacokinetics, and safety of caspofungin (CAS) were investigated in the treatment and prophylaxis of invasive pulmonary aspergillosis due to Aspergillus fumigatus in persistently neutropenic rabbits. Antifungal therapy consisted of 1, 3, or 6 mg of CAS/kg of body weight/day (CAS1, CAS3, and CAS6, respectively) or 1 mg of deoxycholate amphotericin B (AMB)/kg/day intravenously for 12 days starting 24 h after endotracheal inoculation. Prophylaxis (CAS1) was initiated 4 days before endotracheal inoculation. Rabbits treated with CAS had significant improvement in survival and reduction in organism-mediated pulmonary injury (OMPI) measured by pulmonary infarct score and total lung weight (P < 0.01). However, animals treated with CAS demonstrated a paradoxical trend toward increased residual fungal burden (log CFU per gram) and increased serum galactomannan antigen index (GMI) despite improved survival. Rabbits receiving prophylactic CAS1 also showed significant improvement in survival and reduction in OMPI (P < 0.01), but there was no effect on residual fungal burden. In vitro tetrazolium salt hyphal damage assays and histologic studies demonstrated that CAS had concentration- and dose-dependent effects on hyphal structural integrity. In parallel with a decline in GMI, AMB significantly reduced the pulmonary tissue burden of A. fumigatus (P < or = 0.01). The CAS1, CAS3, and CAS6 dose regimens demonstrated dose-proportional exposure and maintained drug levels in plasma above the MIC for the entire 24-h dosing interval at doses that were > or =3 mg/kg/day. As serial galactomannan antigen levels may be used for therapeutic monitoring, one should be aware that profoundly neutropenic patients receiving echinocandins for aspergillosis might have persistent galactomannan antigenemia despite clinical improvement. CAS improved survival, reduced pulmonary injury, and caused dose-dependent hyphal damage but with no reduction in residual fungal burden or galactomannan antigenemia in persistently neutropenic rabbits with invasive pulmonary aspergillosis.

The impact of culture isolation of Aspergillus species: a hospital-based survey of aspergillosis

The term "aspergillosis" comprises several categories of infection: invasive aspergillosis; chronic necrotizing aspergillosis; aspergilloma, or fungus ball; and allergic bronchopulmonary aspergillosis. In 24 medical centers, we examined the impact of a culture positive for Aspergillus species on the diagnosis, risk factors, management, and outcome associated with these diseases. Most Aspergillus culture isolates from nonsterile body sites do not represent disease. However, for high-risk patients, such as allogeneic bone marrow transplant recipients (60%), persons with hematologic cancer (50%), and those with signs of neutropenia (60%) or malnutrition (30%), a positive culture result is associated with invasive disease. When such risk factors as human immunodeficiency virus infection (20%), solid-organ transplantation (20%), corticosteroid use (20%), or an underlying pulmonary disease (10%) are associated with a positive culture result, clinical judgment and better diagnostic tests are necessary. The management of invasive aspergillosis remains suboptimal: only 38% of patients are alive 3 months after diagnosis. Chronic necrotizing aspergillosis, aspergilloma, and allergic bronchopulmonary aspergillosis have variable management strategies and better short-term outcomes.