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

EDTA as an adjunct antifungal agent for invasive pulmonary aspergillosis in a rodent model

Rats immunosuppressed by the administration of cyclophosphamide and cortisone acetate and then infected with Aspergillus fumigatus were treated with an antifungal drug, EDTA, or a combination of one of the antifungal agents, amphotericin B lipid complex (ABLC; 5 mg/kg of body weight/day for 7 days), and EDTA (30 mg/kg/day for 7 days). The mortality rate was reduced, the duration of survival was increased, fewer A. fumigatus organisms were recovered from the lungs, and less-severe lung lesions were seen histopathologically in the rats receiving the combination treatment than in the rats receiving either an antifungal agent or EDTA alone. Further studies regarding the mechanisms of EDTA and its interactions with ABLC are warranted, and further studies are needed to more fully examine the safety, tolerance, and optimal dosing of EDTA in the treatment of this and other fungal infections.

Intrapulmonary penetration of voriconazole in patients receiving an oral prophylactic regimen

Voriconazole penetrated well into the pulmonary epithelial lining fluid (ELF) in lung transplant patients receiving oral prophylaxis. The ELF concentrations exceeded those of the plasma, with an average ELF-to-plasma ratio of 11 (+/-8). A strong association between plasma and ELF concentrations (r(2) = 0.95) was noted.

Sequential or combination antifungal therapy with voriconazole and liposomal amphotericin B in a Guinea pig model of invasive aspergillosis

We evaluated combinations of voriconazole (VRC) and liposomal amphotericin B (L-AMB) in a guinea pig invasive aspergillosis model. Simultaneous VRC and L-AMB was most effective, although VRC monotherapy was also effective. These regimens as well as sequential L-AMB followed by VRC were more effective than L-AMB alone or VRC followed by L-AMB.

Voriconazole treatment for subacute invasive and chronic pulmonary aspergillosis

BACKGROUND

Voriconazole is a novel triazole antifungal with a broad spectrum including Aspergillus species. We conducted an open, noncomparative multicenter study to evaluate the efficacy and safety of voriconazole in subacute invasive and chronic pulmonary aspergillosis (CPA).

METHODS

Patients without profound neutropenia and a proven or probable diagnosis of subacute invasive aspergillosis (IA) or CPA received voriconazole 200 mg twice daily for a period of 4-24 weeks as primary or salvage therapy. Dose escalation was allowed if efficacy was suboptimal, and toleration and safety were satisfactory. Response was assessed by clinical, radiological and mycological changes. A complete or partial response in subacute IA and improved or stable in CPA were assessed as favorable responses.

RESULTS

Of 39 patients treated, 36 were assessable. The majority of patients had subacute IA (n = 21), proven in all 11 extra-pulmonary and in 23/25 (92%) of the pulmonary cases. Voriconazole was given as primary therapy in 22 (61%). All patients receiving salvage therapy (n = 14) had refractory IA, having failed itraconazole or amphotericin B (AmB) or both. Overall, a complete or partial response was seen in 9/21(43%) of subacute IA and improved or stable in 12/15 (80%) of those with CPA. Adverse events, mainly liver function test abnormalities, skin reactions, and visual disturbances were mild and transient, leading to early discontinuation of treatment in 5 cases.

CONCLUSIONS

In patients with subacute IA and CPA, voriconazole was efficacious as salvage or primary therapy.

Invasive Aspergillosis with Central Nervous System Dissemination in a Presumably Immunocompetent, Non-neutropenic Patient: Case Report and Review

We present a case of a 45-year-old gentlemen with invasive Aspergillosis who has no apparent immune deficiencies. Follow up imaging shows improvement after the initiation of therapy. The case is accompanied by a brief discussion over invasive aspergillosis.

Diagnostic strategy in cancer patients with acute respiratory failure

OBJECTIVE

Nearly 15% of cancer patients experience acute respiratory failure (ARF) requiring admission to the intensive care unit, where their mortality is about 50%. This review focuses on ARF in cancer patients. The most recent literature is reviewed, and emphasis is placed on current controversies, most notably the risk/benefit ratio of fiberoptic bronchoscopy and BAL in patients with severe hypoxemia.

BACKGROUND

Fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) is the cornerstone of the causal diagnosis. However, the low diagnostic yield of about 50%, related to the widespread use of broad-spectrum antimicrobial therapy in cancer patients, has generated interest in high-resolution computed tomography (HRCT) and primary surgical lung biopsy. In patients with hypoxemia, bronchoscopy and BAL may trigger a need for invasive mechanical ventilation, thus considerably decreasing the chances of survival.

DISCUSSION

The place for recently developed, effective, noninvasive diagnostic tools (tests on sputum, blood, urine, and nasopharyngeal aspirates) needs to be determined. The prognosis is not markedly influenced by cancer characteristics; it is determined chiefly by the cause of ARF, need for mechanical ventilation, and presence of other organ failures. Although noninvasive ventilation reduces the need for endotracheal intubation and diminishes mortality rate, its prolonged use in patients with severe disease may preclude optimal diagnostic and therapeutic management. The appropriateness of switching to endotracheal mechanical ventilation in patients who fail noninvasive ventilation warrants evaluation.

CONCLUSION

This review discusses risks and benefits from invasive and non invasive diagnostic and therapeutic strategies in critically ill cancer patients with acute respiratory failure. Avenues for research are also suggested in order to improve survival in these very high risk patients.

Impact of the intensity of the pretransplantation conditioning regimen in patients with prior invasive aspergillosis undergoing allogeneic hematopoietic stem cell transplantation: A retrospective survey of the Infectious Diseases Working Party of the European Group for Blood and Marrow Transplantation

In this retrospective study, we analyzed the outcomes of 129 patients who underwent an allogeneic hematopoietic stem cell transplantation (allo-HSCT) and had a history of probable or proven invasive aspergillosis (IA), of whom 57 (44%) received a reduced-intensity conditioning (RIC). Overall, 27 patients with IA progressed after the allo-HSCT (cumulative incidence [CumInc] at 2 years, 22%). The variables that increased the 2-year CumInc of IA progression were (1) longer duration of neutropenia after transplantation; (2) advanced status of the underlying disease; and (3) less than 6 weeks from start of systemic anti-Aspergillus therapy and the allo-HSCT. In addition, (4) conventional myeloablative conditioning increased the risk of progression early after transplantation (before day 30) only, while 3 variables increased the risk beyond day 30 were (5) cytomegalovirus disease; (6) bone marrow or cord blood as source of stem cells; and (7) grades II to IV acute graft-versus-host disease (GVHD). A risk model for progression was generated, defined as low (0-1 risk factors, 6% incidence), intermediate (2-3 risk factors, 27% incidence), or high risk (> or = 3 risk factors, 72% incidence [P < .001]). These findings may help in the interpretation and design of future studies on secondary prophylaxis of IA after an allo-HSCT.

Micafungin (FK463), alone or in combination with other systemic antifungal agents, for the treatment of acute invasive aspergillosis

BACKGROUND

Micafungin (FK463) is a new lipopeptide compound (echinocandin) with activity against Aspergillus and Candida species. This study evaluated the safety and efficacy of micafungin in patients with proven or probable invasive aspergillosis (IA).

METHODS

A multinational, non-comparative study was conducted to examine proven or probable (pulmonary only) Aspergillus species infection in a wide variety of patient populations. The study employed an open-label design utilizing micafungin alone or in combination with another systemic antifungal agent. Criteria for IA and therapeutic responses were judged by an independent panel.

RESULTS

Of the 331 patients enrolled, only 225 met diagnostic criteria for IA as determined by the independent panel and received at least one dose of micafungin. Patients included 98/225 who had undergone hematopoietic stem cell transplantation (HSCT) (88/98 allogeneic), 48 with graft versus host disease (GVHD), and 83/225 who had received chemotherapy for hematologic malignancy. A favorable response rate at the end of therapy was seen in 35.6% (80/225) of patients. Of those only treated with micafungin, favorable responses were seen in 6/12 (50%) of the primary and 9/22 (40.9%) of the salvage therapy group, with corresponding numbers in the combination treatment groups of 5/17 (29.4%) and 60/174 (34.5%) of the primary and salvage treatment groups, respectively. Of the 326 micafungin-treated patients, 183 (56.1%) died during therapy or in the 6-week follow-up phase; 107 (58.5%) deaths were attributable to IA.

CONCLUSIONS

Micafungin as primary or salvage therapy proved efficacious and safe in high-risk patients with IA, although patient numbers are small in the micafungin-only groups.

In vitro release by Aspergillus fumigatus of galactofuranose antigens, 1,3-beta-D-glucan, and DNA, surrogate markers used for diagnosis of invasive aspergillosis

Aspergillus markers are becoming increasingly important for the early diagnosis of invasive aspergillosis. The kinetics of release of these surrogate markers, however, is largely unknown. We investigated the release of beta-(1-5)-galactofuranosyl (galf) antigens (Platelia Aspergillus), 1,3-beta-D-glucan (BG) (Fungitell), and DNA (PCR) in an in vitro model of Aspergillus fumigatus. The results showed that release is correlated to the growth phase of the fungus, which depends on available nutrients. Whereas galf antigens and BG are released during logarithmic growth, DNA is released only after mycelium breakdown. During early logarithmic growth, galf antigens seem to be released somewhat earlier than BG. Furthermore, galf antigen concentrations of more than 120,000 times the serum cutoff value (0.5 ng/ml) can be measured, while BG concentrations reach a value only 978 times the serum cutoff value (60 pg/ml). During lytical growth, release of galf antigens further increased to a maximum level, which depended on pH. After that, the concentration of galf antigens stayed high (pH 7.4) or decreased to zero within 4 days (pH 5.0). In contrast to galf antigens, BG concentration decreased after 1 day of growth. The decrease of galf components seems to be due to the enzyme beta-galactofuranosidase, which is able to destroy galf epitopes and whose activity fluctuates in the culture filtrates in parallel with galf antigen concentration. Fungal DNA seems to be released only due to autolysis caused by nutrient limitation. In conclusion, several factors clearly influence the release of surrogate markers in vitro. These same factors might also play a role at the infection site of Aspergillus disease in humans.

A renal aspergilloma--an unusual presentation of aspergillosis in an HIV patient

BACKGROUND

Aspergillosis is a fungal infection occasionally found in immunosuppressed patients. The recommended management of patients with renal aspergilloma remains unclear.

METHODS

An HIV patient presented with flank pain and an abdominal mass. Renal aspergilloma was diagnosed.

RESULTS

The patient with CD4 above 200 did well with nephrectomy followed by amphotericin therapy for 14 days.

CONCLUSIONS

The merits of surgery followed by antifungal chemotherapy or vice versa are limited. More studies are needed to ascertain the most effective method of treatment for Aspergillosis in HIV patients.

Tratamiento de las infecciones fúngicas invasoras

Invasive fungal infections have increased progressively in the last decades, producing elevated morbidity and mortality. In recent years, there have been numerous advances in the treatment of these diseases, with the introduction of new drugs in clinical practice and the information derived from several types of studies. This has improved the prognosis of some invasive fungal infections and increased the therapeutic options in various clinical situations. This new knowledge must be assessed to determine its application in clinical practice, taking into account available scientific evidence and clinical experience. With this aim, the Andalusian Society of Infectious Diseases has developed this consensus document containing recommendations for the treatment of the invasive fungal infections.

Prospects of vaccines for invasive aspergillosis

Invasive aspergillosis is a disease of immunocompromised hosts and the pathogenesis of this disorder is heavily dependent upon the defect within a given host. Consequently, vaccine development is limited by our understanding of effective host responses and by limitations in our knowledge of fungal molecules that elicit protective immunity. Nonetheless, the past few years have witnessed advances in our understanding both of the immune response to this organism and in the relationship between antigenicity and the ability to confer protection. Manipulations that promote the development of T(H)1-associated responses correlate with increased resistance to disease, at least partly because of consequent enhancement of innate cellular effector function. Two areas of investigation most actively being pursued include the search for adjuvants that will allow products of Aspergillus fumigatus to become effective vaccine candidates, regardless of the form of immunity they ordinarily induce, and the identification of the specific antigens that will most effectively elicit beneficial responses. Strategies using antigen-exposed dendritic cells as adjuvants appear to be particularly promising. Though we currently are far away from a candidate that is applicable for human trials, recent progress is encouraging.

Bloodstream Infections among Heart Transplant Recipients

BACKGROUND

Heart transplant (HT) recipients are prone to life-threatening infections, including bloodstream infection (BSI), but information on this topic is particularly scarce.

METHODS

We studied 309 consecutive HT performed at our institution between 1988 and 2003. We assessed the characteristics of each episode of BSI, prophylaxis and immunosuppression used, and possible related factors.

RESULTS

Sixty episodes of BSI occurred in 15.8% of all HT recipients. Rates of BSI/transplanted patient decreased progressively throughout the study period: 21.2%, 14.3%, and 7.5% in each 5-year period (P=0.03). BSI episodes occurred a median of 51 days after transplantation. The main BSI origins were: lower respiratory tract (23%), urinary tract (20%), and catheter-related-BSI (16%). Gram-negative organisms predominated (55.3%), followed by Gram-positive (44.6%). Mortality was 59.2%, with 12.2% directly attributable to BSI. Independent risk factors for BSI after HT were: hemodialysis (OR 6.5; 95% CI 3.2-13), prolonged intensive care unit stay (OR 3.6; 95% CI 1.6-8.1), and viral infection (OR 2.1; 95% CI 1.1-4). BSI was a risk factor for mortality (OR 1.8; 95% CI 1.2-2.8).

CONCLUSION

BSIs have decreased in HT recipients, but still contribute to mortality, mainly if related to pneumonia or polymicrobial infections. Reduction of early postoperative complications and viral infections are amenable goals that may further reduce BSI in this population.

Multicenter, noncomparative study of caspofungin in combination with other antifungals as salvage therapy in adults with invasive aspergillosis

BACKGROUND

Caspofungin inhibits synthesis of beta-1,3-glucan, an essential component of the Aspergillus cell wall. This echinocandin has demonstrated efficacy (45% success) as salvage monotherapy of invasive aspergillosis (IA). Interest remains as to whether caspofungin, in combination with other antifungal classes, can improve the efficacy against IA.

METHODS

The study involved 53 adults with documented IA who were refractory to or intolerant of standard antifungal therapy and received caspofungin and 1 other mold-active antifungal agent (at the investigator's discretion). Efficacy was assessed by signs, symptoms, and radiographs at the end of combination therapy and Day 84 after combination therapy initiation. Favorable (complete or partial) responses required significant clinical and radiographic improvement. Diagnoses and outcomes were assessed by an independent expert.

RESULTS

Among the 53 patients enrolled the most common underlying diseases were acute leukemia (53%), lymphoma (11%), and chronic leukemia (6%). Pulmonary aspergillosis (81%) was the most common site, and most patients (87%) were refractory to prior therapy. Success at the end of combination therapy and Day 84 was 55% (29/53) and 49% (25/51), respectively. Fifty-seven percent of patients with neutropenia and 54% who received an allogeneic hematopoietic stem cell transplant responded favorably. Survival at Day 84 was 55%. Combination therapy, dosed on average for 31.3 days, was well tolerated. Two (4%) serious drug-related adverse events, both attributed to voriconazole, occurred. None of the patients discontinued caspofungin due to toxicity.

CONCLUSIONS

Caspofungin in combination with a triazole or polyene was an effective alternative as salvage therapy for patients with recalcitrant Aspergillus infections.

Consensus definitions for invasive fungal disease: Strengths, limitations, and revisions

The European Organization for Research and Treatment of Cancer (EORTC)/ Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (MSG) consensus definitions for opportunistic invasive fungal infections have achieved their objective in fostering better communication between researchers but their limitations necessitated revision. In the last two years a group of experts drawn from both sides of the Atlantic have agreed a proposal for a new set of definitions that attempt to rectify omissions and problems arising from the original set whilst preserving their basic principles.

Infectious Complications of Cancer Therapy

Advances in the management of cancer, particularly the development of new chemotherapeutic agents, have greatly improved the survival and outcome of patients with hematologic malignancies and solid tumors; overall 5-year survival rates in cancer patients have improved from 39% in the 1960s to 60% in the 1990s.1 However, infection, caused by both the underlying malignancy and cancer chemotherapy, particularly myelosuppressive chemotherapy, remains a persistent challenge.

LaeA, a global regulator of Aspergillus toxins

Several toxins have been implicated in Aspergillus fumigatus pathogenicity. Among these are gliotoxin, fumagillin, fumagatin, and helvolic acid. Recently we have identified a nuclear protein, LaeA, that regulates the production of all of these metabolites. Several criteria support the role of LaeA as a potent A. fumigatus virulence factor. Among these are a decreased ability of the laeA deletion strain (ΔlaeA) to cause fatal infections in the murine model, increased macrophage phagocytosis of ΔlaeA conidia and decreased ability of ΔlaeA to kill polymorphonuclear neutrophils [1]. Here we present our current knowledge of LaeA function and future directions of study of LaeA mechanism.

Posaconazole: a broad-spectrum triazole antifungal

Posaconazale is a new triazole drug being investigated in phase III clinical trials for the treatment and prevention of invasive fungal infections. In-vitro and in-vivo studies showed that posaconazole has broad-spectrum activity against most Candida species, Cryptococcus neoformans, Aspergillus species, Fusarium species, zygomycetes, and endemic fungi. Posaconazole is given orally two to four times daily. This triazole is widely distributed in the body, metabolised mainly by the liver, and is well tolerated, even in long-term courses. Adverse events are generally mild and include headache and gastrointestinal complaints. Posaconazole has shown promising clinical efficacy against life-threatening fungal infections that are often refractory to the currently available antifungal therapies-eg, invasive aspergillosis, fusariosis, and the emerging zygomycosis.

The beta-glucan receptor dectin-1 recognizes specific morphologies of Aspergillus fumigatus

Alveolar macrophages represent a first-line innate host defense mechanism for clearing inhaled Aspergillus fumigatus from the lungs, yet contradictory data exist as to which alveolar macrophage recognition receptor is critical for innate immunity to A. fumigatus. Acknowledging that the A. fumigatus cell wall contains a high beta-1,3–glucan content, we questioned whether the beta-glucan receptor dectin-1 played a role in this recognition process. Monoclonal antibody, soluble receptor, and competitive carbohydrate blockage indicated that the alveolar macrophage inflammatory response, specifically the production of tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), IL-1β, IL-6, CXCL2/macrophage inflammatory protein-2 (MIP-2), CCL3/macrophage inflammatory protein-1α (MIP-1α), granulocyte-colony stimulating factor (G-CSF), and granulocyte monocyte–CSF (GM-CSF), to live A. fumigatus was dependent on recognition via the beta-glucan receptor dectin-1. The inflammatory response was triggered at the highest level by A. fumigatus swollen conidia and early germlings and correlated to the levels of surface-exposed beta glucans, indicating that dectin-1 preferentially recognizes specific morphological forms of A. fumigatus. Intratracheal administration of A. fumigatus conidia to mice in the presence of a soluble dectin-Fc fusion protein reduced both lung proinflammatory cytokine/chemokine levels and cellular recruitment while modestly increasing the A. fumigatus fungal burden, illustrating the importance of beta-glucan–initiated dectin-1 signaling in defense against this pathogen. Collectively, these data show that dectin-1 is centrally required for the generation of alveolar macrophage proinflammatory responses to A. fumigatus and to our knowledge provides the first in vivo evidence for the role of dectin-1 in fungal innate defense.

Individuals with defective immune systems are highly susceptible to infection by parasites, bacteria, viruses, and fungi. Infection by the opportunistic fungal organism Aspergillus fumigatus can be particularly severe in this population. Because many pathogenic microorganisms, including A. fumigatus, enter the body through the lung, it is important to understand the function of its immune system. The alveolar macrophage is one of the first cell types to come in contact with inhaled pathogens. An intense area of research is how lung immune cells—i.e., alveolar macrophages—recognize inhaled pathogens and respond to them. Steele et al. recently discovered that alveolar macrophages express a receptor on their surface, dectin-1, that is essential in recognizing and responding to inhaled fungal pathogens. They now have investigated the interaction between dectin-1 and A. fumigatus to determine how the dectin-1 receptor orchestrates the alveolar macrophage response. They found that alveolar macrophages respond poorly to A. fumigatus when the dectin-1 receptor is blocked. Also, in animal experiments, blocking dectin-1 renders the animals more susceptible to infection with A. fumigatus. This study may lay the foundation for developing new and novel strategies to combat infections caused by A. fumigatus.

Invasive pulmonary aspergillosis in solid organ and bone marrow transplant recipients

BACKGROUND

Invasive pulmonary aspergillosis (IPA) remains a major cause of mortality in transplant recipients. New strategies in therapy are needed.

METHODS

We prospectively followed all solid organ and bone marrow transplant recipients from January 1998 to January 2003 who showed pulmonary infiltrates. We retrospectively analyzed all of the patients diagnosed as having IPA. Clinical and epidemiological data were collected. Influence of new treatment strategies on survival was also analyzed.

RESULTS

Thirty-one cases of API were found: 8 definite, 18 probable, 5 possible among recipients of liver (11), bone marrow (9), kidney (7), kidney-pancreas (3), and heart (1) transplants. Five patients (16%) were previously receiving antifungal prophylaxis. The most common symptoms were fever (74%) and dyspnea and dry cough (48%). Six cases (19%) showed dissemination to extrapulmonary sites: central nervous system (CNS) in five and bone in one. The most common radiographic patterns were alveolar infiltrates (58%); the lesions were usually diffuse and bilateral (58%). The most common Aspergillus species identified was A. fumigatus (74%). The test to detect Aspergillus antigen (galactomannan) in serum performed in 13 cases, was positive in eight (61%). The crude mortality rate was 61% (19 of 31), but in patients on mechanical ventilation, it was 94% (OR 88, IC 95%: 7.1-1094), and in patients with CNS involvement, it was 100%. The influence of the different treatment regimens on survival was analyzed in definite and probable cases: Group 1 (12) included patients who received conventional monotherapy and group 2 (12) patients received combination antifungal therapy or liposomal amphotericin B (1-AMB) at high doses. The mortality in group 1 was 83% (10 of 12), and in group 2 it was 42% (5 of 12) (P < 0.05).

CONCLUSIONS

The mortality rate of IPA remains high, especially among patients with CNS involvement or those under mechanical ventilation. Combined antifungal therapy or monotherapy with 1-AMB at high doses significantly reduced mortality compared with conventional monotherapy.

Reproducibility of low galactomannan enzyme immunoassay index values tested in multiple laboratories

The Platelia galactomannan enzyme immunoassay is a commercially available nonculture method for diagnosing invasive aspergillosis. Recently, steps have been taken to improve sensitivity; specifically, a low (0.5 to 0.7) galactomannan index (GMI) value to determine positivity has been validated by multiple groups. We evaluated the intra-assay and interassay reproducibility at low index levels using three different kit lots on three different days in three different microbiology laboratories. Clinical and spiked sera were blinded and sent with galactomannan enzyme immunoassay (EIA) kits to the participating laboratories. We also prospectively collected data on all galactomannan EIAs performed between 1 September 2003 and 21 July 2004 at the University of Washington Medical Center microbiology laboratory to assess reproducibility of clinical samples analyzed in "real time." From the multilaboratory study, a total of 836 results were available for evaluation. Reproducibility was excellent between laboratories and on different days. Significant variability was seen between runs/lots, which may in part be associated with different threshold control values in different kits. Among the 1,410 clinical samples that were prospectively analyzed, 168 (90%) were confirmed to be positive on repeat testing (GMI, > or =0.5). Among the 19 (10.2%) initially positive samples not confirmed on repeat testing, the majority had a GMI at the threshold of the assay (between 0.5 and 0.7). Our findings suggest that the Platelia galactomannan immunoassay has good reproducibility. However, changes in GMI levels when different kit lots are used, and single samples with low-positive (GMI of 0.5 to 0.7) indices, should be interpreted with caution.

The Aspergillus fumigatus siderophore biosynthetic gene sidA, encoding L-ornithine N5-oxygenase, is required for virulence

Aspergillus fumigatus is the leading cause of invasive mold infection and is a serious problem in immunocompromised populations worldwide. We have previously shown that survival of A. fumigatus in serum may be related to secretion of siderophores. In this study, we identified and characterized the sidA gene of A. fumigatus, which encodes l-ornithine N(5)-oxygenase, the first committed step in hydroxamate siderophore biosynthesis. A. fumigatus sidA codes for a protein of 501 amino acids with significant homology to other fungal l-ornithine N(5)-oxygenases. A stable DeltasidA strain was created by deletion of A. fumigatus sidA. This strain was unable to synthesize the siderophores N',N",N'''-triacetylfusarinine C (TAF) and ferricrocin. Growth of the DeltasidA strain was the same as that of the wild type in rich media; however, the DeltasidA strain was unable to grow in low-iron defined media or media containing 10% human serum unless supplemented with TAF or ferricrocin. No significant differences in ferric reduction activities were observed between the parental strain and the DeltasidA strain, indicating that blocking siderophore secretion did not result in upregulation of this pathway. Unlike the parental strain, the DeltasidA strain was unable to remove iron from human transferrin. A rescued strain (DeltasidA + sidA) was constructed; it produced siderophores and had the same growth as the wild type on iron-limited media. Unlike the wild-type and rescued strains, the DeltasidA strain was avirulent in a mouse model of invasive aspergillosis, indicating that sidA is necessary for A. fumigatus virulence.

Hard palate perforation due to invasive aspergillosis in a patient with acute lymphoblastic leukemia

Invasive aspergillosis (IA) is a major cause of morbidity and mortality in immunosuppressed patients. Primary oral invasive aspergillosis is a rare condition. We present an acute lymphoblastic leukemia (ALL) patient with hard palate perforation due to invasive aspergillosis. Two months after the appearance of the fungal lesions, perforation of the hard palate was seen despite amphotericin-b and itracanazole therapy. After debridement of necrotic tissue the patient was followed for spontaneous closure for 6 months but it was seen that the fistula persisted despite the disappearance of the infection. The patient was operated for closure of the palatal fistula and there was no recurrence in 6 months of follow up. Surgical and medical management was performed successfully. Invasive oral aspergillosis is a potentially lethal disease and it should be considered in immunosuppressed patients with oral lesions.

Galactomannan and computed tomography-based preemptive antifungal therapy in neutropenic patients at high risk for invasive fungal infection: a prospective feasibility study

BACKGROUND

Empirical antifungal therapy is the standard treatment for persistent or relapsing antibiotic-resistant neutropenic fever. However, overtreatment resulting in increased toxicity and treatment-related cost is a major shortcoming of such therapy. We assessed the feasibility of a "preemptive" approach based on the incorporation of sensitive, noninvasive diagnostic tests for consecutive high-risk neutropenic patients who had received fluconazole prophylaxis while avoiding empirical therapy.

METHODS

A total of 136 treatment episodes for persons who were at risk of acquiring invasive fungal infection (IFI) were screened for the presence of galactomannan with an enzyme immunoassay. A diagnostic evaluation, which included thoracic computed tomography scanning (HRCT) and bronchoscopy with lavage, was performed on the basis of well-defined clinical, radiological, and microbiological criteria. Only seropositive patients and patients with a positive microbiological test result plus supportive radiological findings received liposomal amphotericin B.

RESULTS

Neutropenic fever developed in 117 episodes, of which at least 41 episodes (35%) satisfied existing criteria for empirical antifungal therapy. However, our protocol-driven preemptive approach reduced the rate of antifungal use for these episodes from 35% to 7.7% (a 78% reduction) and led to the early initiation of antifungal therapy in 10 episodes (7.3%) that were clinically not suspected of being IFI. No undetected cases of invasive aspergillosis were identified; 1 case of zygomycosis was missed. Breakthrough candidemia was diagnosed by conventional culture techniques and was treated successfully. With use of a preemptive approach, the 12-week survival rate for patients with IFI was 63.6% (it was 63.1% for those with invasive aspergillosis).

CONCLUSION

Preemptive therapy based on enzyme immunoassay and HRCT reduced the exposure to expensive and potentially toxic drugs and offered effective antifungal control, but it failed to detect non-Aspergillus IFI.

Electron microscopic findings for micafungin-treated experimental pulmonary aspergillosis in mice

We performed a scanning and transmission electron microscopic study on the efficacy of micafungin (MCFG) to understand what kind of damage MCFG causes to Aspergillus and to confirm its previously reported in vitro killing activity against Aspergillus in a mouse model of pulmonary aspergillosis. Aspergillus hyphae in MCFG-treated mice displayed hyphal burst, evidenced as either flattened or atrophied appearance and leakage of cellular contents after collapse of the cell wall. Thus, MCFG can induce the destruction of Aspergillus hyphae at the focus of infection. The results of the present study indicate that MCFG improves pulmonary aspergillosis due to lethal damage to Aspergillus hyphae. This action can effectively reduce the invasive ability of Aspergillus even though MCFG does not sterilize the fungal burden.

Advances and challenges in management of invasive mycoses

Invasive mycoses pose a major diagnostic and therapeutic challenge. Advances in antifungal agents and diagnostic methods offer the potential for improved outcomes in patients with these infections, which are often lethal. Many fungal pathogens occur almost exclusively in opportunistic settings--in the immunocompromised host--and these infections are the focus of this review. Several areas of ongoing challenge remain, including the emergence of resistant organisms and the absence of reliable markers for early identification of patients at risk of developing invasive fungal disease. This Seminar reviews the changing epidemiology of invasive mycoses, new diagnostic methods, and recent therapeutic options and current management strategies for these opportunistic pathogens.

Galactomannan does not precede major signs on a pulmonary computerized tomographic scan suggestive of invasive aspergillosis in patients with hematological malignancies

BACKGROUND

Detection of serum galactomannan (GM) antigen and presence of the halo sign on a pulmonary computerized tomographic (CT) scan have a high specificity but a low sensitivity to diagnose invasive aspergillosis (IA) in patients at risk for this disease. To our knowledge, the relationship between the time at which pulmonary infiltrates are detected by CT and the time at which GM antigens are detected by enzyme immunoassay (EIA) has not been studied.

METHODS

In a prospective study, tests for detection of GM were performed twice weekly for patients with hematological malignancies who had undergone hematopoetic stem cell transplantation (HSCT) or had received induction and/or consolidation chemotherapy. A pulmonary CT scan was performed once weekly. Infiltrates were defined as either major or minor signs. IA was classified as proven, probable, or possible, in accordance with the definition stated by the European Organization for Research and Treatment of Cancer-Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group.

RESULTS

We analyzed 161 episodes of infection in 107 patients (65 allogeneic HSCT recipients, 30 autologous HSCT recipients, and 66 induction and/or consolidation chemotherapy recipients). A total of 109 episodes with no IA, 32 episodes with possible IA, and 20 episodes with probable or proven IA were identified. Minor pulmonary signs were detected by CT in 70 episodes (43%), and major pulmonary signs were detected by CT in 11 episodes (7%). Univariate and multivariate analyses revealed no significant association between detection of GM by EIA and detection of abnormal pulmonary signs by CT. A significant association was found between GM levels and receipt of piperacillin-tazobactam. GM test results were not positive before major signs were seen on CT images. Only 7 (10%) of 70 patients with minor pulmonary signs had positive GM test results before detection of the greatest pathologic change by CT.

CONCLUSIONS

We show that detection of GM by EIA does not precede detection of major lesions by pulmonary CT. In the clinical setting, the decision to administer mold-active treatment should based on detection of new pulmonary infiltrates on CT performed early during infection, rather than on results of EIA for detection of GM.

Invasive Fungal Infections in Living Unrelated Renal Transplantation

In many developing countries, renal transplantation from paid, unrelated donors constitutes the main type of renal transplantation. Several medical and social problems are likely to occur in association with this practice. Among the many medical complications, invasive fungal infections are the most feared. In this report, we describe our experience with 3 patients who underwent living unrelated renal transplantation (LURTX) and developed this complication. One patient developed disseminated mucormycosis, 1 developed invasive aspergillosis (IA), and the third developed central nervous system (CNS) infection with Ramichloridium mackenziei. Two died within a few months after the diagnosis, whereas the third developed hemiplegia and is debilitated.

Caspofungin as first line therapy of pulmonary invasive fungal infections in 32 immunocompromised patients with hematologic malignancies

Invasive Fungal Infections (IFI) remain a severe and major complication among patients with hematologic diseases, but the recent availability of new antifungal agents (echinocandins and new azoles) have improved the chance of cure. Caspofungin (Cancidas-Merck) is a large lipopeptide molecule able to inhibit the enzyme complex 1,3-d-glucan synthetase; this action specifically damages the fungal cell wall. Caspofungin (CAS) is active, in vitro and in vivo, against most Candida species and Aspergillus species. We report on our experience with this drug as first-line therapy for proven or probable pulmonary IFI in immunocompromised patients with hematologic malignancies. Thirty-two consecutive patients (20 males and 12 females, with a median age of 52 yr) have been treated with CAS (27 acute leukemias, 1 chronic leukemia, 3 lymphomas and 1 multiple myeloma). Sixteen patients (50%) had a relapsed or resistant hematologic disease, while 12 patients were in complete remission and 4 were at onset of disease; 8/32 (25%) developed IFI after a hematopoietic stem cell transplant (HSCT) procedure. Seven out of 32 patients (22%) had a proven pulmonary IFI (7/7 Aspergillosis) and 25 (78%) had a probable IFI with pulmonary localization as defined according to international consensus. Thirty-one patients (97%) had less than 1000 granulocytes/mL at onset of infection and at the start of CAS therapy. The CAS was given at the dose of 70 mg on day 1, followed by 50 mg/day. Median duration of CAS therapy was 20 d (range 8-64); all the 31 neutropenic patients received concomitant granulocyte colony-stimulating factor (G-CSF). The overall response rate was 56% (18/32) with 12/18 complete responses and 6/18 partial responses; two patients (6%) had a stable disease. Twelve out of 32 (38%) did not respond and seven died of mycotic infection. Univariate analysis showed that granulocytes recovery (>500/mL vs. <500/mL) and status of hematologic disease (remission/onset vs. refractory/relapsed) were significantly associated to favourable outcome. No clinical adverse events (AE) were reported and only a grades I and II transient increase of serum alkaline phosphatase and/or transaminases occurred in 4/32 (12%) patients. After CAS therapy six non-responders and six cases with a partial or stable response were rescued with voriconazole. Two out of six patients (33%) in the former group and 6/6 (100%) in the latter obtained a complete resolution of IFI. Our experience suggests an efficacy of CAS, in combination with G-CSF, as first-line treatment of proven or probable IFI with pulmonary localization. The drug was well tolerated and there were no significant hepatic AE even in patients receiving CAS with cyclosporine after a HSCT. A significant proportion of non-responders or partial responders to CAS can be rescued with a subsequent voriconazole-based therapy.

Cost Advantage of Voriconazole over Amphotericin B Deoxycholate for Primary Treatment of Invasive Aspergillosis

STUDY OBJECTIVES

Using data from a published clinical trial, our objectives were to compare the cost advantage of voriconazole over amphotericin B deoxycholate (AmBd) for primary treatment of invasive aspergillosis and to determine the financial impact the findings would have in a real-world clinical setting.

DESIGN

Pharmacoeconomic analysis.

SETTING

University hospital.

PATIENTS

Two hundred seventy-seven patients in the modified intent-to-treat population.

MEASUREMENTS AND MAIN RESULTS

An analysis was performed of drug acquisition costs for all patients in the modified intent-to-treat population, which consisted of 144 patients in the voriconazole group and 133 in the AmBd group. The analysis included costs of initial drug therapy; conversion from intravenous to oral treatment for patients receiving voriconazole; and the types, dosages, and duration of other licensed [Food and Drug Administration-approved] antifungal therapy (OLAT) for up to three OLAT regimens/patient. Current drug costs for our university hospital were used for all calculations. Total voriconazole costs were $784,405 ($581,008 for initial therapy with voriconazole, $203,397 for OLAT) compared with $852,238 for AmBd ($31,677 for initial AmBd therapy, $820,561 for OLAT). Over the 12-week study period, the cost/patient was $961 less for patients whose initial treatment was voriconazole than for those whose initial treatment was AmBd. Other licensed antifungal therapy accounted for 26% and 96% of total drug costs for voriconazole and AmBd, respectively. Other licensed antifungal therapy was given to 36% of voriconazole-treated patients and 80% of AmBd-treated patients.

CONCLUSION

These data demonstrate the importance of evaluating total drug costs when comparing treatment regimens and not just initial therapy. Initial therapy with voriconazole had a cost advantage over AmBd in total antifungal drug cost/patient.

Cerebral aspergillosis due to Aspergillus fumigatus in AIDS patient: first culture - proven case reported in Brazil

Cerebral aspergillosis is a rare cause of brain expansive lesion in AIDS patients. We report the first culture-proven case of brain abscess due to Aspergillus fumigatus in a Brazilian AIDS patient. The patient, a 26 year-old male with human immunodeficiency virus (HIV) infection and history of pulmonary tuberculosis and cerebral toxoplasmosis, had fever, cough, dyspnea, and two episodes of seizures. The brain computerized tomography (CT) showed a bi-parietal and parasagittal hypodense lesion with peripheral enhancement, and significant mass effect. There was started anti-Toxoplasma treatment. Three weeks later, the patient presented mental confusion, and a new brain CT evidenced increase in the lesion. He underwent brain biopsy, draining 10 mL of purulent material. The direct mycological examination revealed septated and hyaline hyphae. There was started amphotericin B deoxycholate. The culture of the material demonstrated presence of the Aspergillus fumigatus. The following two months, the patient was submitted to three surgeries, with insertion of drainage catheter and administration of amphotericin B intralesional. Three months after hospital admission, his neurological condition suffered discrete changes. However, he died due to intrahospital pneumonia. Brain abscess caused by Aspergillus fumigatus must be considered in the differential diagnosis of the brain expansive lesions in AIDS patients in Brazil.

Successful treatment of invasive pulmonary aspergillosis in an immunocompetent host

Immunocompromised individuals are susceptible to pulmonary Aspergillus infection, but invasive Aspergillus infection is extremely rare in the presence of normal immunity. A case of invasive pulmonary aspergillosis in an immunocompetent 57-year-old female who was successfully treated with liposomal amphotericin-B is reported here.

Efficacy of Abelcet and caspofungin, alone or in combination, against CNS aspergillosis in a murine model

OBJECTIVES

Currently, few options exist to treat central nervous system (CNS) aspergillosis, which is usually fatal. We tested the efficacy of Abelcet and caspofungin, alone and in combination for treatment of this disease.

METHODS

Male CD-1 mice were immunosuppressed with 200 mg/kg cyclophosphamide 2 days prior to infection and every 5 days thereafter. In the first study, mice were infected intracerebrally with 2.1 x 10(6) conidia/mouse of Aspergillus fumigatus; 10 days of once daily therapy began one day later. Groups of 10 received 0.8, 4, or 8 mg/kg of Abelcet, intravenously (iv), or caspofungin, intraperitoneally, 0.8 mg/kg of conventional amphotericin B (AmB) iv, or no treatment. In a second study, mice were challenged with 6.4 x 10(6) conidia and given no treatment, 8 mg/kg of Abelcet or caspofungin, alone or in combination. On day 14, cfu were determined in survivors by plating of organ homogenates.

RESULTS

In the first study, mice given any regimen of Abelcet or caspofungin had a survival rate > or =80% whereas untreated had 90% mortality. All drug regimens prolonged survival (P < or = 0.0008) and reduced cfu (P < or = 0.0001-0.003) recovered from the brains and kidneys compared with untreated. Abelcet showed an apparent dose-related reduction of cfu in the brains. Abelcet at 4 or 8 mg/kg were equivalent to AmB in reducing cfu from both organs (P > 0.05); AmB was superior to 0.8 mg/kg of Abelcet in the brain only (P < 0.02). Abelcet at 8 mg/kg or AmB at 0.8 mg/kg were superior to all regimens of caspofungin in reducing cfu (P < or = 0.05-0.001). In the second study, Abelcet alone significantly prolonged survival and reduced cfu in the organs versus the controls. Caspofungin did not significantly prolong survival or reduce cfu in comparison with the controls. In combination, Abelcet and caspofungin were equivalent to Abelcet alone.

CONCLUSIONS

Abelcet proved to be efficacious, but not curative, in the treatment of CNS aspergillosis and was equivalent overall to conventional AmB. Caspofungin was not as effective against the larger inoculum, but did not enhance or interfere with the efficacy of Abelcet. Since Abelcet displayed dose-responsive efficacy, it is possible higher doses could produce superior results, yet not show toxicity.

Evaluation of serum sandwich enzyme-linked immunosorbent assay for circulating galactomannan during caspofungin therapy: results from the caspofungin invasive aspergillosis study

There has been minimal clinical experience with the use of the Aspergillus galactomannan enzyme-linked immunosorbent assay (ELISA) for patients receiving echinocandin therapy. We reviewed the experience with the galactomannan ELISA for 17 patients in a study of caspofungin treatment for invasive aspergillosis. The rate of successful outcomes for these patients was similar to that overall for participants in the study. Trends in antigenemia levels correlated with clinical and radiographic findings.

Epidemiological study of invasive pulmonary aspergillosis in a haematology unit by molecular typing of environmental and patient isolates of Aspergillus fumigatus

In order to determine the possible relationship between environmental contamination by Aspergillus fumigatus and occurrence of invasive aspergillosis, a one-year prospective study was carried out in the haematology ward of Hautepierre Hospital, Strasbourg, France. During the study period, 21 environmental isolates and 26 clinical isolates of A. fumigatus were collected. Each was genotyped using a random amplification of polymorphic DNA (RAPD) technique. Thirty-four distinct profiles were identified by RAPD analysis, indicating the great genetic diversity of A. fumigatus isolated from infected patients and from the environment. For two patients, RAPD analysis demonstrated concurrent infection by at least two different strains. In two cases, a genetic similarity was noted between isolates obtained from a patient and from the environment.

Aspergillus infections in lung transplant recipients: risk factors and outcome

This retrospective study of 251 lung transplant patients aimed to determine the prevalence, clinical presentation and mortality of Aspergillus infection in order to define specific risk factors and to compare survival in patients with and without infection. Aspergillus was isolated from 86 (33%) cases, which involved colonisation (n = 50), tracheobronchial lesions (n = 17) or invasive aspergillosis (n = 19). Overall, aspergillosis had an impact on survival (p < 0.05); in fact the 5-year mortality rate was substantially higher in single lung transplant recipients with bronchial anastomotic infection, and in those with late-onset infections and chronic rejection. A significant association (p < 0.05) was found between acute rejection and the time at which fungal infection was diagnosed. Aspergillus infection was not related to cytomegalovirus infection or treatment with corticosteroids. The mortality rate for invasive infections was 78% and was related to survival (p < 0.0001); invasive aspergillosis was also associated with chronic rejection (p < 0.05), but not with high corticosteroid doses (p 0.49) or use of tacrolimus (p 0.73). In conclusion, Aspergillus infection was associated with a reduction in the 5-year survival rate of lung transplant recipients, and this was particularly true for patients infected with the invasive forms and for patients with single lung transplants, bronchial anastomotic infection and chronic rejection. Isolation of Aspergillus spp. from respiratory samples preceded acute rejection, and may be a marker of graft dysfunction and/or airway inflammation. Close monitoring, or even pre-emptive antifungal therapy, is recommended for patients with chronic rejection or bronchial airway mechanical abnormalities and persistent Aspergillus colonisation.

Overview of transplant mycology

PURPOSE

The epidemiology, clinical manifestation, diagnosis, and management of invasive mycoses in transplant patients are described.

SUMMARY

The incidence of and mortality from invasive mycoses have increased in transplant patients. Candida and Aspergillus are the two most common fungal pathogens in this patient population. The use of immunosuppressive and myeloablative therapies and other factors increases the risk of invasive mycoses. A high index of suspicion and clinical clues are needed for the diagnosis of Candida and Aspergillus infections because reliable diagnostic techniques are not available and the patient presentation is nonspecific. Targeted prophylaxis for patients at high risk for morbidity and mortality and early, aggressive treatment using broad-spectrum antifungal agents are recommended. Prophylaxis using itraconazole reduces the risk of treatment failure due to resistant pathogens compared with fluconazole. Voriconazole might prove advantageous compared with fluconazole and itraconazole for prophylaxis because of its extended spectrum and predictable blood levels. Caspofungin seems as effective as and less toxic than amphotericin B for this use. Voriconazole is more effective than amphotericin B for the treatment of aspergillosis. Caspofungin is comparable to voriconazole in efficacy as salvage treatment after failure to respond to other antifungal agents.

CONCLUSION

Caspofungin plus voriconazole and other combination therapies often are used for the treatment of aspergillosis yet data to support such use are yet to be produced. The investigational agents posaconazole, micafungin, and anidulafungin appear promising as salvage treatment of various invasive mycoses.

Pediatric aspergillosis: disease and treatment differences in children

Invasive aspergillosis is an increasing problem, yet there are few specific data on pediatric aspergillosis. The underlying patient diseases and treatments differ in children and adults, and there is a heterogeneity of invasive aspergillosis that extends to children. Although new diagnostic tools hold great promise for adult patients, it appears that they have limited usefulness in children without the appropriate testing. Antifungal management of pediatric aspergillosis also requires unique dosing schemes that are not used in adult patients.

Combination treatment of invasive fungal infections

The persistence of high morbidity and mortality from systemic fungal infections despite the availability of novel antifungals points to the need for effective treatment strategies. Treatment of invasive fungal infections is often hampered by drug toxicity, tolerability, and specificity issues, and added complications often arise due to the lack of diagnostic tests and to treatment complexities. Combination therapy has been suggested as a possible approach to improve treatment outcome. In this article, we undertake a historical review of studies of combination therapy and also focus on recent studies involving newly approved antifungal agents. The limitations surrounding antifungal combinations include nonuniform interpretation criteria, inability to predict the likelihood of clinical success, strain variability, and variations in pharmacodynamic/pharmacokinetic properties of antifungals used in combination. The issue of antagonism between polyenes and azoles is beginning to be addressed, but data regarding other drug combinations are not adequate for us to draw definite conclusions. However, recent data have identified potentially useful combinations. Standardization of assay methods and adoption of common interpretive criteria are essential to avoid discrepancies between different in vitro studies. Larger clinical trials are needed to assess whether combination therapy improves survival and treatment outcome in the most seriously debilitated patients afflicted with life-threatening fungal infections.

Isolation of Aspergillus spp. from the respiratory tract in critically ill patients: risk factors, clinical presentation and outcome

Introduction

Our aims were to assess risk factors, clinical features, management and outcomes in critically ill patients in whom Aspergillus spp. were isolated from respiratory secretions, using a database from a study designed to assess fungal infections.

Methods

A multicentre prospective study was conducted over a 9-month period in 73 intensive care units (ICUs) and included patients with an ICU stay longer than 7 days. Tracheal aspirate and urine samples, and oropharyngeal and gastric swabs were collected and cultured each week. On admission to the ICU and at the initiation of antifungal therapy, the severity of illness was evaluated using the Acute Physiology and Chronic Health Evaluation II score. Retrospectively, isolation of Aspergillus spp. was considered to reflect colonization if the patient did not fulfil criteria for pneumonia, and infection if the patient met criteria for pulmonary infection and if the clinician in charge considered the isolation to be clinically valuable. Risk factors, antifungal use and duration of therapy were noted.

Results

Out of a total of 1756 patients, Aspergillus spp. were recovered in 36. Treatment with steroids (odds ratio = 4.5) and chronic obstructive pulmonary disease (odds ratio = 2.9) were significantly associated with Aspergillus spp. isolation in multivariate analysis. In 14 patients isolation of Aspergillus spp. was interpreted as colonization, in 20 it was interpreted as invasive aspergillosis, and two cases were not classified. The mortality rates were 50% in the colonization group and 80% in the invasive infection group. Autopsy was performed in five patients with clinically suspected infection and confirmed the diagnosis in all of these cases.

Conclusion

In critically ill patients, treatment should be considered if features of pulmonary infection are present and Aspergillus spp. are isolated from respiratory secretions.

Aspergillus hyphae in infected tissue: evidence of physiologic adaptation and effect on culture recovery

Microbiologic cultures of fungi are routinely incubated at ambient temperatures in room air, and the rate of recovery of Aspergillus species from clinical specimens is poor. Failure of current culture methods to mimic the physiologic temperature and low-oxygen environment found in hypha-laden infected tissue may underlie this poor recovery. Experiments were performed to compare the recovery of Aspergillus spp. incubated at 35 degrees C in 6% O(2)-10% CO(2) with that at 25 degrees C in room air. The samples tested included Aspergillus-infected tissue specimens from a dog model and human autopsies, experimental anaerobically stressed Aspergillus inocula, and 10,062 consecutive clinical specimens. Culture at 35 degrees C in 6% O(2)-10% CO(2) significantly enhanced the recovery of Aspergillus spp. from the infected autopsy tissue samples. Incubation at 35 degrees C alone resulted in approximately 10-fold-improved culture recovery from the experimentally stressed hyphae, and the 6% O(2)-10% CO(2) atmosphere independently favored growth under temperature-matched conditions. Finally, incubation at 35 degrees C (in room air) improved the overall recovery of Aspergillus spp. from clinical specimens by 31%. Culture at 35 degrees C in a microaerobic atmosphere significantly enhances the recovery of Aspergillus spp. from various sources. Aspergillus hyphae growing in infected tissue appear to be adapted to the physiologic temperature and hypoxic milieu.

Economic evaluation of voriconazole compared with conventional amphotericin B for the primary treatment of aspergillosis in immunocompromised patients

OBJECTIVE

The objective of this study was to conduct an economic evaluation of voriconazole compared with conventional amphotericin B deoxycholate (CAB) using data from a recently reported randomized comparative trial in patients with various underlying immunosuppressive conditions. This trial demonstrated the superiority of voriconazole in terms of clinical response, survival and safety when used as primary therapy for invasive aspergillosis.

METHODS

A decision analytic model was designed using an expert panel and populated primarily with efficacy and resource utilization data collected prospectively during the clinical trial. The analysis was carried out from the perspective of the health care system and all costs are reported in 2002 US dollars.

RESULTS

Average total treatment costs per patient were 10% lower in the voriconazole arm ($30 664) than in the CAB arm ($34 144), resulting from reduced consumption of hospital resources and fewer changes in antifungal therapy. In the base case analysis, voriconazole provided an average saving of $3481 per treated patient, resulted in a lower cost per survivor ($43 310 versus $58 971) and a lower cost per successfully treated patient ($58 100 versus $108 124) compared with CAB. Sensitivity analyses demonstrated that the cost savings observed were maintained over a wide range of alternative values for both unit costs and resource utilization, including length of hospital stay, time spent in intensive care units, bed day costs and the cost of lipid formulations of amphotericin B.

CONCLUSION

Incremental cost-effectiveness analysis indicated the dominance of voriconazole because of both lower costs and greater efficacy.