Antifungal therapy in 'bone marrow failure'

Amphotericin B lipid soluble formulations versus amphotericin B in cancer patients with neutropenia

BACKGROUND

Patients with cancer who are treated with chemotherapy or receive a bone marrow transplant have an increased risk of acquiring fungal infections. Such infections can be life-threatening. Antifungal drugs are therefore often given prophylactically to such patients, or when they have a fever.

OBJECTIVES

To compare the benefits and harms of lipid soluble formulations of amphotericin B with conventional amphotericin B in cancer patients with neutropenia.

SEARCH METHODS

We searched PubMed from 1966 to 7 July 2014 and the reference lists of identified articles.

SELECTION CRITERIA

Randomised clinical trials comparing lipid soluble formulations of amphotericin B with conventional amphotericin B.

DATA COLLECTION AND ANALYSIS

The two review authors independently assessed trial eligibility and risk of bias and abstracted data.

MAIN RESULTS

We found 13 trials (1960 patients). Lipid-based amphotericin B was not more effective than conventional amphotericin B on mortality (relative risk (RR) 0.5; 95% confidence interval (CI) 0.64 to 1.14) but decreased invasive fungal infection (RR 0.65; 95% CI 0.44 to 0.97), nephrotoxicity defined as a 100% increase in serum creatinine (RR 0.45; 95% CI 0.37 to 0.54), and number of dropouts (RR 0.78; 95% CI 0.62 to 0.97).For the drug used in most patients, AmBisome (4 trials, 1214 patients), there was no significant difference in mortality (RR 0.77; 95% CI 0.54 to 1.10) whereas it tended to be more effective than conventional amphotericin B on invasive fungal infection (RR 0.63; 95% CI 0.39 to 1.01, P value 0.053).AmBisome, amphotericin B in Intralipid (6 trials, 379 patients), amphotericin B colloidal dispersion (ABCD) (2 trials, 262 patients), and amphotericin B lipid complex (ABLC) (1 trial, 105 patients) all decreased the occurrence of nephrotoxicity, but conventional amphotericin B was rarely administered under optimal circumstances.

AUTHORS' CONCLUSIONS

It is not clear whether there are any advantages of lipid-based formulations if conventional amphotericin B is administered under optimal circumstances, and their high cost prohibits routine use in most settings. There is a need for large trials comparing lipid-based formulations of amphotericin B with conventional amphotericin B given in the same dose, with routine premedication for prevention of infusion-related toxicity, and with supplementation with fluid, potassium, and magnesium for prevention of nephrotoxicity.

Voriconazole versus amphotericin B or fluconazole in cancer patients with neutropenia

BACKGROUND

Opportunistic fungal infections are a major cause of morbidity and mortality in neutropenic cancer patients and antifungal therapy is used both empirically and therapeutically in these patients.

OBJECTIVES

To compare the benefits and harms of voriconazole with those of amphotericin B and fluconazole when used for prevention or treatment of invasive fungal infections in cancer patients with neutropenia.

SEARCH METHODS

Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2014, Issue 1 2014), MEDLINE (to January 2014). Letters, abstracts and unpublished trials were accepted. Contact was made with trial authors and industry.

SELECTION CRITERIA

Randomised clinical trials comparing voriconazole with amphotericin B or fluconazole.

DATA COLLECTION AND ANALYSIS

Data on mortality, invasive fungal infection, colonisation, use of additional (escape) antifungal therapy and adverse effects leading to discontinuation of therapy were extracted independently by two review authors.

MAIN RESULTS

Three trials were included. One trial compared voriconazole to liposomal amphotericin B as empirical treatment of fever of unknown origin (suspected fungal infection) in neutropenic cancer patients (849 patients, 58 deaths). The second trial compared voriconazole to amphotericin B deoxycholate in the treatment of confirmed and presumed invasive Aspergillus infections (391 patients, 98 deaths). The third trial compared fluconazole to voriconazole for prophylaxis of fungal infections in patients receiving allogeneic stem cell transplantation (600 patients, number of deaths not stated). In the first trial, voriconazole was significantly inferior to liposomal amphotericin B according to the trial authors' prespecified criteria. More patients died in the voriconazole group and a claimed significant reduction in the number of breakthrough fungal infections disappeared when patients arbitrarily excluded from the analysis by the trial authors were included. In the second trial, the deoxycholate preparation of amphotericin B was used without any indication of the use of premedication to counter side effects and replacement of electrolytes or use of salt water. This choice of comparator resulted in a marked difference in the duration of treatment on the trial drugs (77 days with voriconazole versus 10 days with amphotericin B) and precluded meaningful comparisons of the benefits and harms of the two drugs. The third trial failed to find a difference in fungal free survival or invasive fungal infections at 180 days when voriconazole was compared to fluconazole.

AUTHORS' CONCLUSIONS

Liposomal amphotericin B is significantly more effective than voriconazole for empirical therapy of fungal infections in neutropenic cancer patients and should be preferred. For treatment of aspergillosis, there are no trials that have compared voriconazole with amphotericin B given under optimal conditions. For prophylactic fungal treatment in patients receiving allogeneic stem cell transplantation, there was no difference between voriconazole and fluconazole regarding fungal free survival or invasive fungal infections.

Characterization of theEscherichia coliAntifungal Protein PPEBL21

An antifungal protein isolated from Escherichia coli BL21 (PPEBL21) and predicted to be alcohol dehydrogenase (ADH) was subjected to biological characterization. The PPEBL21, indeed, demonstrated propionaldehyde-specific ADH activity. The Km and Vmax of PPEBL21 were found to be 644.8 μM and 1.2 U/mg, respectively. In-gel activity assay also showed that PPEBL21 was a propionaldehyde-specific ADH. The pI of PPEBL21 was observed to be 7.8. PPEBL21 was found to be stable up to a temperature of 40°C with optimum activity at pH 7.5. The decrease in pH decreased the activity of PPEBL21. These results suggested that PPEBL21 having alcohol dehydrogenase activity and stability at significantly high temperature might be an important lead antifungal molecule. Experiments were performed to identify the possible target of PPEBL21 in the pathogen A. fumigatus. Results revealed that PPEBL21 inhibited completely the expression of a 16 kDa protein in A. fumigatus. The 16 kDa protein of A. fumigatus targeted by PPEBL21 was identified as a hypothetical protein by peptide mass fingerprinting. It is thus hypothesized that a 16 kDa factor is essentially required by A. fumigatus for survival and its impaired synthesis due to treatment with PPEBL21 may lead to the death of pathogen.

Influence of amphotericin B and amphotericin B colloidal dispersion on the functions of human phagocytes in defence against Aspergillus species

This study investigated the in vitro effects of amphotericin B and amphotericin B colloidal dispersion (ABCD) on phagocytosis and inhibition of germination of clinical isolates of Aspergillus spp. by monocyte-derived macrophages (MDMs). Both amphotericin B and ABCD caused significant reductions in uptake of conidia of Aspergillus spp. by MDMs (p < 0.01). The inhibition of germination was superior with conidia of Aspergillus fumigatus, Aspergillus niger and Aspergillus terreus isolates. Aspergillus flavus growth was significantly less inhibited of either antimycotic as compared to A. fumigatus and A. terreus (p < 0.01).We demonstrate that amphotericin B or ABCD acts as a potent inhibitor of Aspergillus germination. By contrast, treatment of MDMs with these antimycotics diminished phagocytosis of conidia in vitro.

Posaconazole enhances the activity of amphotericin B against Aspergillus hyphae in vitro

The MICs and fractional inhibitory concentrations of posaconazole (POS) and voriconazole (VRZ), alone and in combination with amphotericin B (AMB), for the conidia and hyphae of 100 Aspergillus isolates were evaluated. POS-AMB had more synergistic activity against hyphae (75% of isolates) than VRZ-AMB (37%) and significantly more synergistic activity against hyphae than against conidia (12%).

Polymerase chain reaction screening for fungemia and/or invasive fungal infections in patients with hematologic malignancies

INTRODUCTION

Invasive fungal infections (IFIs) are a life-threatening complication in patients with hematologic malignancies, mainly in acute leukemia patients, following chemotherapy. IFI incidence is increasing, and associated mortality remains high due to unreliable diagnosis. Antifungal drugs are often limited by inadequate antimicrobial spectrum and side effects. Thus, the detection of circulating fungal DNA has been advocated as a rapid, more sensitive diagnostic tool.

PATIENTS AND METHODS

Between June 01 and January 03, weekly blood samples (1,311) were screened from 193 patients undergoing intensive myelosuppressive or immunosuppressive therapy. IFI cases were classified according to European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria. Fungal DNA was extracted from whole blood and amplified using polymerase chain reaction (PCR) published primers that bind to the conserved regions of the fungal 18S rRNA gene sequence. In our study, two or more consecutive positive samples were always associated with fungal disease.

RESULTS

PCR screening predicted the development of IFI to be 17 days (median). This test had a specificity of 91.1% and a sensitivity of 75%. IFI incidence was 7.8%.

DISCUSSION

Therefore, our results confirm the potential usefulness of PCR serial screening and the clinical applicability in everyday routine. PCR screening offers a noninvasive repeatable aid to the diagnosis of IFI.

Voriconazole versus amphotericin B in cancer patients with neutropenia

BACKGROUND

Opportunistic fungal infections are a major cause of morbidity and mortality in neutropenic cancer patients and antifungal therapy are used both empirically and therapeutically in these patients.

OBJECTIVES

To compare the benefits and harms of voriconazole with those of amphotericin B and fluconazole when used for prevention or treatment of invasive fungal infections in cancer patients with neutropenia.

SEARCH STRATEGY

MEDLINE and the Cochrane Library (May 2005). Letters, abstracts and unpublished trials were accepted. Contact to authors and industry.

SELECTION CRITERIA

Randomised trials comparing voriconazole with amphotericin B or fluconazole.

DATA COLLECTION AND ANALYSIS

Data on mortality, invasive fungal infection, colonisation, use of additional (escape) antifungal therapy and adverse effects leading to discontinuation of therapy were extracted by two authors independently.

MAIN RESULTS

Two trials were included. One trial compared voriconazole to liposomal amphotericin B as empirical treatment of fever of unknown origin (suspected fungal infections) in neutropenic cancer patients (849 patients, 58 deaths). The other trial compared voriconazole to amphotericin B deoxycholate in the treatment of confirmed and presumed invasive Aspergillus infections (391 patients, 98 deaths). In the first trial, voriconazole was significantly inferior to liposomal amphotericin B according to the authors' prespecified criteria. More patients died in the voriconazole group and a claimed significant reduction in the number of breakthrough fungal infections disappeared when patients arbitrarily excluded from analysis by the authors were included. In the second trial, the deoxycholate preparation of amphotericin B was used without any indication of the use of premedication and substitution with electrolytes and salt water to avoid handicapping this drug. This choice of comparator resulted in a marked difference in the duration of treatment on trial drugs (77 days with voriconazole versus 10 days with amphotericin B), and precludes meaningful comparisons of the benefits and harms of the two drugs.

AUTHORS' CONCLUSIONS

Liposomal amphotericin B is significantly more effective than voriconazole for empirical therapy of neutropenic cancer patients and should be preferred. For treatment of aspergillosis, there are no trials that have compared voriconazole with amphotericin B given under optimal conditions.

Investigations on anti-Aspergillus properties of bacterial products

AIMS

To investigate the anti-Aspergillus properties of bacterial products.

METHODS AND RESULTS

In the present study, 12 bacterial strains were screened for antifungal activity against Aspergilli. The culture supernatant and lysates of Pseudomonas aeruginosa, Bacillus cereus, Escherichia coli (BL21, DH5alpha, HB101, XL Blue), Klebsiella pneumoniae, Streptomyces thermonitrificans, Streptococcus pneumoniae, Enterobacter aerogenes, Staphylococcus aureus and Salmonella typhi were examined for antifungal activity in protein concentration ranging from 1000.0 to 7.8 microg ml-1 using microbroth dilution assay. The lysate of Salm. typhi and E. coli BL21 exhibited the maximum activity against Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger. Their in vitro minimum inhibitory concentrations (MICs) were found to be 15.6-31.2 microg ml-1 by microbroth dilution and spore germination inhibition assays. In disc diffusion assay, a concentration of 3.1 microg disc-1 of Salm. typhi lysate showed significant activity against Aspergilli. Escherichia coli BL21 exhibited similar activity at 6.2 microg disc-1. The work on identification of molecule endowed with antimycotic properties is in progress.

CONCLUSION

The products of Salm. typhi and E. coli demonstrated significant activity against Aspergillus species.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first time that E. coli has been reported for anti-Aspergillus activity. It could be an important source of biologically active compounds useful for developing better new antifungal drugs/or probiotics.

A fraction from Escherichia coli with anti-Aspergillus properties

The products of various strains of Escherichia coli (BL21, DH5alpha, HB101 and XL Blue) were investigated for antimycotic properties using pathogenic isolates of Aspergillus. Co-culture experiments revealed that E. coli strains exhibited variable activity against Aspergillus fumigatus. The lysates prepared from DH5alpha, HB101 and XL Blue strains of E. coli showed inhibitory activity against A. fumigatus in the protein concentration range of 62.50 to 250.00 microg ml(-1). The highest activity was seen in the lysate of BL21, which inhibited the growth of A. fumigatus and Aspergillus flavus completely at a concentration of 31.25 microg protein ml(-1). The MIC of BL21 lysate against Aspergillus niger was found to be 62.50 microg ml(-1). The in vitro toxicity of BL21 lysate was evaluated using a haemolytic assay. A BL21 lysate protein concentration of 1250.00 microg ml(-1) was found to be nontoxic to human erythrocytes. The standard drug amphotericin B lysed 100 % of erythrocytes at a concentration of 37.50 microg ml(-1). SDS-PAGE showed the presence of at least 15 major proteins in the lysate of BL21. Ion-exchange chromatography resolved the BL21 lysate into five fractions and fraction III was found to be endowed with anti-Aspergillus properties. The MIC of this fraction was found to be 3.90 microg ml(-1). Further work on the purification of the active molecule and its characterization is in progress.

Metaanálisis de la seguridad y eficacia de la anfotericina B liposómica en el tratamiento empírico de la neutropenia febril

BACKGROUND AND OBJECTIVE

We compared the safety and efficacy of liposomal amphotericin B with other formulations of amphotericin B and voriconazol as an empirical treatment of febrile neutropenia.

MATERIAL AND METHOD

Several randomized controlled clinical trials, designed to evaluate the safety and/or efficacy of liposomal amphotericin B in the empirical treatment of febrile neutropenia, in comparison with other amphotericin B formulations or voriconazol, were identified by means of a search in MEDLINE, EMBASE and Cochrane Controlled Trials Register's data bases. American Society of Microbiology and American Society of Clinical Oncology abstracts, presented between 1999 and 2002, were also included in the search. Prior to data extraction, concepts like nephrotoxicity, infusion-related adverse events and efficacy (success rate and mortality) were defined.

RESULTS

Two studies comparing liposomal amphotericin B with conventional amphotericin B, one comparing liposomal amphotericin B with amphotericin B lipid complex and one comparing liposomal amphotericin B with voriconazol were included in the analysis. Patients treated with liposomal amphotericin B had lower nephrotoxicity than patients treated with other amphotericin B formulations or with conventional amphotericin B (RR = 0.49); conversely, no statistically significant differences with regard to voriconazol were observed. In terms of efficacy, mortality rate and therapeutic failure, patients treated with limposomal amphotericin B showed a slightly higher efficacy.

CONCLUSIONS

Liposomal amphotericin B is a lipidic formulation with a slightly higher efficacy than other amphotericin B formulations and voriconazol. In terms of nephrotoxicity, liposomal amphotericin B showed lower nephrotoxicity than other amphotericines while its safety rates were similar to those of voriconazol.

Continuous infusion of escalated doses of amphotericin B deoxycholate: an open-label observational study

Amphotericin B deoxycholate (AmB-d) remains a mainstay of antifungal therapy for immunocompromised patients, despite being associated with significant therapy-related toxicity. Because continuous infusion of AmB-d is better tolerated than traditional administration over 2-6 hours, we evaluated escalation of the AmB-d dose in 33 patients (31 of whom were neutropenic), for whom the initial dosage of AmB-d (1 mg/kg/day) was gradually increased to 2.0 mg/kg/day when renal function remained stable and the drug was tolerated. Dose escalation was possible without delay in 28 patients. Median duration of AmB-d therapy was 16 days (range, 7-72 days). Infusion-related reactions accompanied <18% of AmB-d infusions. Twenty-seven patients had a decrease in creatinine clearance while receiving AmB-d therapy. A >2-fold decrease in creatine clearance was observed in 5 patients, and the decrease was dose-limiting in only 1 patient; no dialysis was required. In conclusion, continuous infusion of AmB-d escalated to 2.0 mg/kg/day seems not to cause additional impairment of vital organ functions and to be well tolerated by most patients.

Catheter-related candidemia caused by Candida lipolytica in a patient receiving allogeneic bone marrow transplantation

Candida lipolytica was recovered from the blood and the central venous catheter in a patient receiving allogeneic bone marrow transplantation. Two C. lipolytica strains from different geographical areas and the ATCC 9773 strain of C. lipolytica were used as controls. C. lipolytica was identified by standard methods. MICs indicated antifungal susceptibilities to amphotericin B, fluconazole, and itraconazole for all strains. In vitro testing and scanning electron microscopy showed that C. lipolytica was capable of producing large amounts of viscid slime material in glucose-containing solution, likely responsible for the ability of the yeast to adhere to catheter surfaces. Restriction fragment length polymorphisms revealed an identical profile for all clinical isolates, unrelated to those observed for the control strains. This finding suggested the absence of microevolutionary changes in the population of the infecting strain, despite the length of the sepsis and the potential selective pressure of amphotericin B, which had been administered to the patient for about 20 days. The genomic differences that emerged between the isolates and the control strains were indicative of a certain degree of genetic diversity between C. lipolytica isolates from different geographical areas.

Invasive aspergillosis in haematological malignancies: clinical findings and management for intensive chemotherapy completion

Sixty-one cases of Aspergillus infection (35 acute myeloid leukemia, 15 acute lymphoid leukemia, one myelodysplastic syndrome, two aplastic anemia, eight non-Hodgkin's lymphoma) seen in our department between January 1989 and July 1999 were studied retrospectively to evaluate the clinical characteristics, to ascertain the factors that influenced the outcome from mycotic infections, and whether early diagnosis and prolonged therapy permitted completion of scheduled intensive chemotherapy and bone marrow transplantation (BMT) without fungal recurrence. The patients were divided into three diagnostic categories: proven aspergillosis (autoptic or histologic diagnosis) n = 39, probable aspergillosis (radiological diagnosis with positive microbiology) n = 9, and possible aspergillosis (radiological diagnosis alone) n = 13. In the same period among 675 acute leukemia patients the incidence of proven or probable aspergillosis was 7.1%. At onset of infection 92% of patients were neutropenic (< 0.5 x 10(9)/L). The most frequent site of infection was the lung (90%); disseminated disease was present in 20 patients. Among 44 assessable patients, 12 (27%) failed to respond to early antifungal therapy and died. Thirty-two patients were cured with antifungal treatment, three of five nonneutropenic with only itraconazole, the others with amphotericin B 1 mg/Kg/day with or without itraconazole subsequently or with liposomal amphotericin, Ambisome, if renal toxicity occurred. Twenty-four of 29 neutropenic responders, all affected by acute leukemia, continued scheduled intensive chemotherapies. Pulmonary lobectomy was successfully combined with medical treatment in two cases before scheduled BMT. After infection nine patients were submitted to BMT (six allo, one marrow unrelated donor (MUD), two auto) with Ambisome or itraconazole as secondary prophylaxis without fungal relapse (follow-up: 25-99 months). The median time from fungal infection to transplant was five months, range 3-10. Thirteen of 29 surviving patients had leukemia relapse, but only three (23%) of these showed also fungal infection recurrence. In conclusion, a high index of suspicion and careful clinical and radiological examinations are the key to identifying infected patients early and to programming the following therapeutic steps. Above all in leukemia patients, prompt and aggressive administration of antifungal agents seems to improve the outcome of invasive fungal disease and to permit intensive chemotherapy completion and transplant.

Liposomal amphotericin B and surgery in the successful treatment of invasive pulmonary mucormycosis in a patient with acute T-lymphoblastic leukemia

Pulmonary mucormycosis is a usually fatal opportunistic infection in immunocompromised patients. We describe the first case of an adult patient with hematological malignancy and profound neutropenia to survive a disseminated pulmonary Rhizomucor pusillus infection. Early diagnostic procedures combined with high doses of liposomal amphotericin B and surgical resection may have contributed to the successful outcome.

Successful treatment of invasive mould infection affecting lung and brain in an adult suffering from acute leukaemia

We describe in detail a 67-yr-old woman who was treated with a cytostatic combination chemotherapy for newly diagnosed common-acute lymphoblastic leukaemia. At the end of induction therapy, the patient acquired invasive mould infection affecting lung and brain. The patient entered complete remission of her leukaemia. Treatment with liposomal amphotericin B was initiated along with surgical excision of the fungal brain abscess. Intrathecal instillation of amphotericin B deoxycholate was started using an Ommaya reservoir because of an anatomical connection between the postoperative cavity and the ventricle. Full dose cytostatic chemotherapy was continued with little delay. A computerised tomography scan of the chest performed 2 months later revealed no fungal abscesses. Magnetic resonance imaging of the brain did not reveal any fungal manifestation. During maintenance therapy/week 69, the patient relapsed from leukaemia. High doses of intravenous liposomal amphotericin B were administered prophylactically. The patient's leukaemia proved refractory to reinduction chemotherapy and the patient died from pneumonia 8 wk later. Post mortem microbiological investigation and histopathological examination of lung and brain tissue did not reveal any macroscopical or microscopical fungal manifestations. This case underlines the feasibility and successful application of combined antileukaemic, antifungal and surgical therapy in a patient with acute leukaemia.

Malignancy: Granulocyte Colony Stimulating Factor Increases the Efficacy of Conventional Amphotericin in the Treatment of Presumed Deep-Seated Fungal Infection in Neutropenic Patients following Intensive Chemotherapy or Bone Marrow Transplantation for Haematological Malignancies

A prospective, comparative study of empiric amphotericin B with, or without, granulocyte colony stimulating factor was carried out to assess whether the addition of granulocyte colony stimulating factor to empiric amphotericin B improves the clinical response in neutropenic patients with suspected or proven fungal infection. Fifty nine neutropenic adults with haematological malignancy and antibiotic-refractory fever or clinical evidence of deep-seated fungal infection were studied. Patients received intravenous colloidal amphotericin B (1 milligram per kilogram body weight) with or without subcutaneous granulocyte colony stimulating factor (three to five micrograms per kilogram body weight). Thirty patients received amphotericin alone and 29 amphotericin plus granulocyte colony stimulating factor. Nearly twice as many patients responded to amphotericin B with concomitant administration of granulocyte colony stimulating factor (62%) as responded to amphotericin alone (33%; difference in proportions 0.29, 95%CI 0.03-0.54). Clinical response in patients receiving granulocyte colony stimulating factor coincided with neutrophil recovery in most cases. Addition of granulocyte colony stimulating factor to empiric amphotericin B significantly reduced the number of patients requiring salvage therapy with lipid-associated or liposomal formulations of amphotericin B addition of granulocyte colony stimulating factor to empiric intravenous amphotericin B improves the response rate and thereby reduces the number of patients requiring salvage therapy with liposomal or lipid-associated preparations of amphotericin B.

Lipid-based amphotericin B: a review of the last 10 years of use

The last decade has been remarkable for the dramatic increase in the prevalence of serious fungal infections in patients with haematological disorders and neutropenic cancer patients. The mortality rate of deep-seated infection has been in excess of 90% and there is no doubt that this is one of the greatest challenges currently facing haematologists and oncologists. The development of the lipid-based drugs - liposomal amphotericin (AmBisome(R)), amphotericin B lipid complex, ABLC (Abelcet(R)), amphotericin B colloidal dispersion, Amphocil (ABCD(R)), has meant that doses of amphotericin B can be safely escalated for the first time whilst the problems of nephrotoxicity, infusion related reactions (including chills, rigors, fevers and hypoxia) can be reduced. These toxicities are variably reduced with AmBisome more than Abelcet and more than Amphocil and there is little information from randomised trials other than for AmBisome. AmBisome used in the setting of persistent fever and neutropenia not responding after 3-4 days of intravenous antibiotics, is associated with less breakthrough systemic fungal infections. There is also much less need for premedication, including steroids, compared with amphotericin B and Abelcet. The use of intermittent doses of Ambisome given prophylactically is now being explored. A new and exciting era of antifungal therapy is opening up with new compounds, such as itraconazole voriconazole, posaconazole and echinocandins, being investigated and for the first time, we also have options for combination therapy and prophylaxis.

Studies of in vitro activities of voriconazole and itraconazole against Aspergillus hyphae using viability staining

The minimal fungicidal concentrations (MFCs) of voriconazole and itraconazole for five clinical isolates each of Aspergillus terreus, Aspergillus fumigatus, Aspergillus flavus, and Aspergillus niger were determined by a broth macrodilution method. Conidial suspensions as inocula were compared to hyphae as inocula since the invasive form of aspergillosis is manifested by the appearance of hyphal structures. In addition, cell viability staining with the dye FUN-1 was performed to assess time-dependent damage of hyphae exposed to various concentrations of the antifungal agents. With conidial inocula the MFC ranges of voriconazole were 0.5 to 4 microg/ml and those of itraconazole were 0.25 to 2 microg/ml, whereas the MFCs (2 to >16 microg/ml) with hyphal inocula were substantially higher (P < 0.01) for both itraconazole and voriconazole. Only minor differences between the tested antifungals were observed since 16 of 20 and 17 of 20 of the isolates of Aspergillus spp. tested appeared to be killed by voriconazole and itraconazole, respectively. The results of FUN-1 viability staining correlated closely to colony counts, but various time- and dose-dependent levels of viability of hyphae were also observed. In conclusion, our study demonstrates the importance of the type of inoculum used to test antifungals and the applicability of FUN-1 staining as a rapid and sensitive method for assaying the viability of hyphae.

Treatment and outcome of invasive Aspergillus infections in allogeneic BMT recipients

The outcome of invasive aspergillosis (IA) has been considered poor in allogeneic BMT recipients. We analyzed retrospectively the treatment and outcome of IA diagnosed during life in a recent cohort of 20 allogeneic BMT recipients. All patients were initially treated with amphotericin B (AmB) (conventional 16, liposomal 4). Due to toxicity, conventional AmB was changed to a liposomal preparation in 10 patients. Five patients also received itraconazole and three underwent surgery. Of 19 evaluable patients, two patients achieved a complete response and a partial response was observed in five patients (response rate 37%). The median survival was 37 days after the diagnosis. Only two patients (10%) were cured. The prognosis of allogeneic BMT recipients with IA has remained poor. Although treatment responses are common, immunosuppression aggravated by GVHD and its treatment, as well as the commonly disseminated presentation of IA, seem to be major obstacles to the success of therapy. Bone Marrow Transplantation (2000) 26, 759-762.

Diagnostic aspects of invasive Aspergillus infections in allogeneic BMT recipients

To investigate diagnostic aspects of invasive aspergillosis (IA) in allogeneic BMT recipients, the charts of 22 consecutive patients with IA transplanted in 1989-1995 were reviewed. IA was diagnosed 69-466 days (median 131 days) post BMT. In 16 patients (73%), a definite or probable diagnosis of IA was made during life. Respiratory symptoms were the presenting feature in half of the patients followed by neurological symptoms (27%). Chest X-ray revealed single or multiple nodular lesions in 10 patients; cavitation was observed in five patients. Tissue biopsy was the most common method of diagnosis (nine patients: lungs 6, liver 1, subcutaneous tissue 1, brain 1). Five IA cases were detected by nine guided fine needle lung biopsies in eight patients and without complications. Bronchoalveolar lavage was performed in 14 patients with findings suggestive of invasive pulmonary aspergillosis in eight cases. Lungs were the most common organ affected (90%) followed by central nervous system (41%). The diagnosis of IA is still difficult, and a large number of patients have advanced infection at diagnosis. Methods for early diagnosis are needed. Patients with a clinical suspicion of IA should be treated vigorously with antifungal agents during the diagnostic work-up.

Amphotericin B lipid soluble formulations vs amphotericin B in cancer patients with neutropenia

BACKGROUND

Patients with cancer who are treated with chemotherapy or receive a bone marrow transplant have an increased risk of acquiring fungal infections. Such infections can be life-threatening. Antifungal drugs are therefore often given prophylactically to such patients, or when they have a fever.

OBJECTIVES

To compare the effect and adverse effects of AmBisome and other lipid soluble formulations of amphotericin B with conventional amphotericin B in cancer patients with neutropenia.

SEARCH STRATEGY

MEDLINE and Cochrane Library. Unpublished trials from conference proceedings and contact to industry.

SELECTION CRITERIA

Randomised trials comparing lipid soluble formulations of amphotericin B with conventional amphotericin B.

DATA COLLECTION AND ANALYSIS

Data on mortality, invasive fungal infection, nephrotoxicity, serum creatinine and dropouts were extracted by both authors independently.

MAIN RESULTS

AmBisome vs conventional amphotericin B (3 trials, 1149 patients): AmBisome tended to be more effective than conventional amphotericin B for invasive fungal infection (relative risk 0.63, 95% confidence interval 0.39 to 1.01, P=0.053) whereas there was no significant difference in mortality (relative risk 0.74, 95% CI 0.52 to 1.07). AmBisome decreased significantly the incidence of nephrotoxicity, defined as a 100% increase in serum creatinine (relative risk 0.51, 95% CI 0.40 to 0.64). Fewer patients dropped out on AmBisome but the difference was not significant (relative risk 0.78, 95% CI 0.56 to 1. 08). Amphotericin B in Intralipid vs conventional amphotericin B (4 trials, 145 patients): There were no significant differences in clinical effect whereas the patients treated with the lipid soluble formulation experienced significantly less nephrotoxicity (relative risk 0.34, 95% CI 0.15 to 0.75) and smaller increases in serum creatinine (weighted mean difference 32 micromol/l, 95% CI 21 to 43 micromol/l). Amphotericin B colloidal dispersion (ABCD) vs conventional amphotericin B (1 trial, 213 patients): There was lower nephrotoxicity with ABCD (relative risk 0.38, 95% CI 0.25 to 0.59).

REVIEWER'S CONCLUSIONS

AmBisome is a better drug than conventional amphotericin B but its high cost prohibits routine use in most settings. Furthermore, the advantages of AmBisome may be smaller than indicated in our review if conventional amphotericin B is administered under optimal circumstances. It is not clear whether other lipid formulations of amphotericin B could offer a worthwhile advantage compared to conventional amphotericin B.

New perspectives in the diagnosis of systemic fungal infections

Profound and prolonged neutropenia following chemotherapy is a major risk factor for systemic fungal infections. Mortality associated with disseminated fungal infection is high, and treatment with conventional amphotericin B is complicated by renal toxicity. Candida and Aspergillus are among the major pathogens in these patients. Many patients remaining neutropenic over a prolonged period of time will receive empirical antifungal therapy. The clinical and laboratory diagnoses of these infections are neither sensitive nor specific and are generally limited in the early detection of invasive fungal infection. However, several new approaches to diagnosis are being developed, which should be translated into routine practice, based on a greater understanding of the pathogenesis of systemic fungal infection and virulence determinants of fungal pathogens. These include antigen detection and polymerase chain reaction. Patients with presumed fungal infection require more intense and accurate monitoring for signs of disseminated infection. Early diagnosis may guide appropriate treatment and prevent mortality. Continued development of commercial tests should help achieve the objective of definitive diagnostic tests for systemic fungal infections.

Use of spectrophotometric reading for in vitro antifungal susceptibility testing ofAspergillusspp

A comparative study of visual and spectrophotometric MIC endpoint determinations for antifungal susceptibility testing of Aspergillus species was performed. A broth microdilution method adapted from the National Committee for Clinical Laboratory Standards (NCCLS) was used for susceptibility testing of 180 clinical isolates of Aspergillus species against amphotericin B and itraconazole. MICs were determined visually and spectrophotometrically at 490 nm after 24, 48, and 72h of incubation, and MIC pairs were compared. The agreement between the two methods was 99% for amphotericin B and ranged from 95 to 98% for itraconazole. It is concluded that spectrophotometric MIC endpoint determination is a valuable alternative to the visual reference method for susceptibility testing of Aspergillus species.Key words: antifungal, susceptibility testing, Aspergillus, spectrophotometric reading.

Systemic fungal infections in patients with hematologic malignancies: indications and limitations of the antifungal armamentarium

The rates of fungal infections have increased substantially in Europe as well as in North America. Most frequently Aspergillus spp. and Candida spp. are isolated. Despite the recent introduction of new azoles and lipid-based formulations of amphotericin B, there are relatively few randomized, controlled studies on the use of antifungal drugs in patients with hematological malignancies and invasive fungal infections. Conventional amphotericin B is considered the gold standard for the treatment of invasive fungal infections; however, adverse events limit conventional amphotericin B treatment. The newer azoles, fluconazole and itraconazole, are well tolerated; however, fluconazole has no activity against Aspergillus spp. An additional serious problem is the emerging resistance of nonalbicans Candida spp. to fluconazole. In this situation, lipid formulations of amphotericin B seem to be attractive, since the use of these drugs has been shown to be safe and effective. Considerably higher medical costs limit broader application of lipid formulations of amphotericin B. Because of the rapidly increasing incidence of serious fungal infections, we have reviewed current strategies and the role of newer antifungal drugs for the treatment of deep-organ infections.

Supportive care in hematological malignancies: hematopoietic growth factors, infections, transfusion therapy

This article focuses on a selected number of topics among recent developments in the supportive care of hematological malignancies. The first section focuses on the role of hematopoietic growth factors, such as granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, thrombopoietin, interleukin-11, and keratinocyte growth factor. The following sections discuss the management of fungal and viral infections as well as changes in the current policies of platelet transfusion. The focus of this review is on the clinical utility and economic feasibility of the published findings.

A randomized controlled trial of itraconazole versus fluconazole for the prevention of fungal infections in patients with haematological malignancies. U.K. Multicentre Antifungal Prophylaxis Study Group

Fluconazole is widely used as antifungal prophylaxis but it is ineffective against Aspergillus. Itraconazole has a broader spectrum of activity but the capsules give erratic bioavailability in neutropenic patients. We compared itraconazole oral solution (which has an improved pharmacokinetic profile) with fluconazole for antifungal prophylaxis. Adults with haematological malignancies receiving chemotherapy or bone marrow transplants were randomly allocated 5 mg/kg/d itraconazole (itra) solution (288 episodes) or 100 mg fluconazole suspension (flu) (293 episodes) from before the onset of neutropenia until neutrophil recovery or suspected fungal infection. Outcomes were assessed by independent reviewers unaware of the prophylaxis allocation. More proven systemic fungal infections occurred in flu (Aspergillus four, Candida tropicalis one, C. krusei one) than itra (C. albicans one) and more of these were fatal (four versus nil). This difference reached statistical significance when first study episodes were considered separately (six flu versus nil itra, P = 0.03). Significantly more deaths of presumed fungal origin occurred in flu than itra (seven versus nil, P = 0.024). There were significantly more cases of proven aspergillosis in flu than itra (six versus nil, P = 0.038, 5/6 cases were fatal) if those occurring outside the study period are included. Significantly more patients receiving flu required amphotericin B (58 v 39, P = 0.043) but this may have been affected by the fact that the study was not blinded. There were 11 proven mucosal candidal infections in flu and four in itra. Itraconazole solution and fluconazole provide effective prophylaxis against Candida but itraconazole affords greater protection against fatal aspergillosis.

Aspergillus fumigatus endophthalmitis in a patient with acute myeloid leukaemia

A 55-year-old patient developed progressive loss of vision in one eye following induction chemotherapy for acute myeloid leukaemia (AML). Aspergillus fumigatus was cultured from vitreal aspirates. The patient was treated with intravenous and intravitreal amphotericin B but suffered complete loss of vision in her right eye. We believe this is the first report of culture-proven Aspergillus fumigatus endophthalmitis in a patient treated for a haematological malignancy.

AmBisome: an overview of current use

Although amphotericin B has been the gold standard in treating systemic fungal infections, its use is limited by side-effects including nephrotoxicity. In contrast the empiric or therapeutic use of AmBisome is better tolerated, with less nephrotoxicity.

A comparative analysis of lipid-complexed and liposomal amphotericin B preparations in haematological oncology

No comparative clinical information on the properties of lipid-associated amphotericin preparations is presently available. In this single-centre retrospective analysis over a 5-year period the indications, efficacy and toxicity of true liposomal amphotericin (AmBisome) were compared with a lipid complexed preparation (Abelcet). In a novel approach APACHE III scores were used in addition to neutrophil counts, disease status and additional immunosuppression to accurately assess the severity of illness in both groups and enable valid comparison. Overall, AmBisome at a median dose of 1.9 mg/kg/d was found to have similar clinical outcome to Abelcet at a median dose of 4.8 mg/kg/d. Nephrotoxicity and electrolyte abnormalities were similar in both groups. Rigors and febrile episodes were more common with Abelcet. Prospective randomized comparative trials are required to clarify the optimum dosages and therapeutic and economic issues associated with these agents.