Therapy of invasive aspergillosis with itraconazole: improvement of therapeutic efficacy by early diagnosis

A Systematic Review to Assess the Relationship between Disseminated Cerebral Aspergillosis, Leukemias and Lymphomas, and Their Respective Therapeutics

Disseminated disease following invasive pulmonary aspergillosis (IPA) remains a significant contributor to mortality amongst patients with hematologic malignancies (HMs). At the highest risk of mortality are those with disseminated disease to the central nervous system, known as cerebral aspergillosis (CA). However, little is known about the risk factors contributing to disease amongst HM patients. A systematic review using PRISMA guidelines was undertaken to define HM patient subgroups, preventative measures, therapeutic interventions, and outcomes of patients with disseminated CA following IPA. The review resulted in the identification of 761 records, of which 596 articles were screened, with the final inclusion of 47 studies and 76 total patients. From included articles, the proportion of CA was assessed amongst HM patient subgroups. Further, pre-and post-infection characteristics, fungal species, and mortality were evaluated for the total population included and HM patient subgroups. Patients with acute myeloid leukemia and acute lymphoid lymphoma, patients receiving corticosteroids as a part of their HM therapeutic regimen, and anti-fungal prophylaxis constitute the top identified patient populations at risk for disseminated CA. Overall, information presented here indicates that measures for the prevention of IPA should be taken in higher-risk HM patient subgroups. Specifically, the type of anti-fungal therapy used should be carefully considered for those patients with IPA and increased risk for cerebral dissemination. Additional reports detailing patient characteristics are needed to define further the risk of developing disseminated CA from IPA in patients with HMs.

Cooperative Effects of an Antifungal Moiety and DMSO on Pore Formation over Lipid Membranes Revealed by Free Energy Calculations

Itraconazole is a triazole drug widely used in the treatment of fungal infections, and it is in clinical trials for treatment of several cancers. However, the drug suffers from poor solubility, while experiments have shown that itraconazole delivery in liposome nanocarriers improves both circulation half-life and tissue distribution. The drug release mechanism from the nanocarrier is still unknown, and it depends on several factors including membrane stability against defect formation. In this work, we used molecular dynamics simulations and potential of mean force (PMF) calculations to quantify the influence of itraconazole on pore formation over lipid membranes, and we compared the effect by itraconazole with a pore-stabilizing effect by the organic solvent dimethyl sulfoxide (DMSO). According to the PMFs, both itraconazole and DMSO greatly reduce the free energy of pore formation, by up to ∼20 kJ mol^-1. However, whereas large concentrations of itraconazole of 8 mol % (relative to lipid) were required, only small concentrations of a few mole % DMSO (relative to water) were sufficient to stabilize pores. In addition, itraconazole and DMSO facilitate pore formation by different mechanisms. Whereas itraconazole predominantly aids the formation of a partial defect with a locally thinned membrane, DMSO mainly stabilizes a transmembrane water needle by shielding it from the hydrophobic core. Notably, the two distinct mechanisms act cooperatively upon adding both itraconazole and DMSO to the membrane, as revealed by an additional reduction of the pore free energy. Overall, our simulations reveal molecular mechanisms and free energies of membrane pore formation by small molecules. We suggest that the stabilization of a locally thinned membrane as well as the shielding of a transmembrane water needle from the hydrophobic membrane core may be a general mechanism by which amphiphilic molecules facilitate pore formation over lipid membranes at sufficient concentrations.

Opportunistic infection of Aspergillus and bacteria in captive Cape vultures (Gyps coprotheres)

OBJECTIVE

To describe clinical signs, pathology, diagnosis and treatment of Cape vultures in which Aspergillus fumigatus (A. fumigatus) and mixed species of bacteria were isolated.

METHODS

Six Cape vultures sourced from South Africa for exhibition at Al Ain Zoo developed illness manifesting as anorexia, dyspnea, polyuria and lethargy. Three vultures died manifesting "pneumonia-like syndrome". These three vultures were necropsied and gross lesions recorded, while organ tissues were collected for histopathology. Internal organs were swabbed for bacteriology and mycology. From live vultures, blood was collected for hematology and biochemistry, oropharyngeal and cloacal swabs were collected for mycology and bacteriology.

RESULTS

A. fumigatus was isolated from the three dead vultures and two live ones that eventually survived. One of the dead vulture and two live vultures were co-infected with A. fumigatus and mixed species of bacteria that included Clostridium perfringens, Pseudomonas, Staphylococcus, Escherichia, Proteus, Enterococcus and Enterbacter. One of the Cape vulture and a Lappet-faced vulture, however, were free of Aspergillus or bacterial infections. At necropsy, intestinal hemorrhages were observed and the lungs were overtly congested with granulomas present on caudal air sac. Histopathological examinations demonstrated granulomatous lesions that were infiltrated by mononuclear cells and giant cells.

CONCLUSIONS

Aspergillosis is a persistent threat to captive birds and we recommend routine health assessments so that early diagnosis may prompt early treatment. It is likely that prompt prophylaxis by broad spectrum antibiotics and antifungals medication contributed to the survival of some of the vultures.

Aspergillosis: diagnosis and treatment

The incidence of invasive aspergillosis is increasing rapidly in the developed world with two Aspergillus spp., A. fumigatus and A. flavus, causing the majority of infections (85-90% and 5-10%, respectively). The major risk factors are profound neutropenia (< or =1000 x 10(6) cells/L), prolonged neutropenia, neutrophil function deficits, and corticosteroid therapy. Useful diagnostic techniques include sputum culture, CT scan, bronchoscopy with microscopy and culture, percutaneous lung biopsy, open lung biopsy and serology. Invasive aspergillosis has an almost 100% mortality rate if untreated. Amphotericin B is the usual first-line therapy although it is associated with a high failure rate. Itraconazole (> or =400 mg daily) is a useful alternative and surgical resection may be life saving in some cases. The efficacy of the initial therapy is critical for improving mortality rates.

Preoperative antifungal therapy may improve survival in patients with Aspergillus brain abscess

OBJECTIVE

The objective of this study was to determine if the preoperative use of antifungal therapy positively influences clinical outcome in patients with Aspergillus brain abscess.

METHODS

We studied 25 patients with confirmed diagnosis of cerebral aspergillosis. We compared baseline characteristics and outcomes of patients treated with either amphotericin B or itraconazole either pre-operatively (n=11) or post-operatively (n=14) at a tertiary care hospital in Karachi.

RESULTS

Twenty-five patients were included in the study. Cerebral aspergillosis was largely a disease of immune competent people (80%). Baseline clinical characteristics between the two treatment groups were comparable i.e., age (P>0.896), gender (P>0.999), coma at presentation (P>0.999), immunosuppression (P>0.623), number of abscesses (P>0.999) and interval between presentation and surgery (P>0.447). Overall mortality was 40%. The overall outcome was significantly better (P<0.001) in patients treated with antifungal therapy before surgery. All 11 patients who received antifungal therapy before surgery survived, but only preoperative itraconazole treatment was statistically associated with an improved survival compared to delayed treatment.

CONCLUSION

Cerebral aspergillosis was largely a disease of immune competent people (80%). Overall mortality was 40%. The outcome was significantly better in patients treated with antifungal therapy (especially itraconazole) before surgery suggesting a possible beneficial effect of pre-surgical treatment with antifungal therapy.

Improved outcome of pulmonary aspergillosis in heart transplant recipients with early diagnosis and itraconazole treatment

Pulmonary aspergillosis is a severe complication in heart transplant recipients. The drug of choice for this infection is amphotericin B, but its use is limited because of its side effects. We observed six cases of pulmonary aspergillosis in a group of 200 patients who had received heart transplants from January 1988 to January 1999. Predisposing factors such as previous rejection, neutropenia and/or cytomegalovirus reactivation were present in all patients. The clinical presentation was characterized by fever and a non-productive cough. X-rays showed monolateral or diffuse infiltrate with or without nodular lesions. The median interval between symptoms and diagnosis was 5 d (range 4-7). Diagnosis was made by culturing trans-tracheal aspirate samples. Aspergillus fumigatus was isolated in 3 patients and A. niger in the other 3. All patients were treated with itraconazole at 200-400 mg/day for 20-60 d and all recovered. One patient treated with the lowest dosage for the shortest term had a recurrence after 1 month and needed a second 30-day course of itraconazole at a higher dosage. No significant side effects were registered. Itraconazole is effective in the therapy of pulmonary aspergillosis, particularly when an early diagnosis is made.

Case report. Mixed systemic mycosis with fatal outcome in a patient with acute myeloblastic leukaemia

Fungal infections represent an increasing problem in immunocompromised patients. The majority of cases are caused by one single fungal pathogen and infections with more than one fungus are very rare. Here we describe a case of combined infection with Aspergillus and a zygomycete species, involving the lungs, spleen and the brain and leading to fatal outcome in spite of early antimycotic therapy.

Fatal invasive aspergillosis in an adolescent with cystic fibrosis

We report on a 13-year-old girl with cystic fibrosis (CF) who developed refractory airflow obstruction despite high-dose steroids. She developed invasive aspergillosis and died despite oral and intravenous antifungal therapy. We speculate that the increasing use of immunosuppressive strategies and aggressive antipseudomonal therapy in CF may lead to an increase in aspergillus lung disease, including invasive aspergillosis in the future.

Antifungal agents. Part II. The azoles

Before 1978, amphotericin B and flucytosine were the only drugs available for the treatment of systemic fungal infections. The imidazoles, miconazole and ketoconazole, were introduced during the next 3 years. Intravenously administered miconazole served a limited therapeutic role and is no longer available. Orally administered ketoconazole, an inexpensive, effective, and convenient option for treating mucosal candidiasis, was widely used for a decade because it was the only available oral therapy for systemic fungal infections. During the 1990s, use of ketoconazole diminished because of the release of the triazoles--fluconazole and itraconazole. Fluconazole is less toxic and has several pharmacologic advantages over ketoconazole, including penetration into the cerebrospinal fluid. In addition, it has superior efficacy against systemic candidiasis, cryptococcosis, and coccidioidomycosis. Despite a myriad of drug interactions and less favorable pharmacologic and toxicity profiles in comparison with fluconazole, itraconazole has become a valuable addition to the antifungal armamentarium. It has excellent activity against sporotrichosis and seems promising in the treatment of aspergillosis. Itraconazole has replaced ketoconazole as the therapy of choice for nonmeningeal, non-life-threatening cases of histoplasmosis, blastomycosis, and paracoccidioidomycosis and is effective in patients with cryptococcosis and coccidioidomycosis, including those with meningitis. Further investigation into the development of new antifungal agents is ongoing.

Invasive Aspergillus sinusitis during bone marrow transplantation

Aspergillus sinusitis is usually a lethal condition in bone marrow transplanted patients. We report the case of a patient known to have a sinus infection with Aspergillus flavus before treatment with allogenic bone marrow transplantation for a refractory acute myelogenous leukemia. Exacerbation of the sinusitis during the neutropenic period required a multidisciplinary approach. Cure was achieved after treatment with a combination of surgery (Caldwell-Luc procedure), long term ABCD (amphotericin B colloidal dispersion) therapy (7 months) and granulocyte transfusions during the period preceding engraftment. The use of granulocyte transfusion in this salvage setting is discussed. Aggressive multimodality management of aspergillus sinusitis in immunosuppressed patients may lead to a cure and might not preclude allogenic transplantation.

Aspergillosis of the central nervous system

The authors report an unusual case involving a 38 year-old man who developed a intracranial abscess caused by Aspergillus of the parietal lobe. Cerebral aspergilloma of an initial pulmonary origin developed in a patient with "Fungus Ball" secondary to tuberculosis sequelae. The diagnosis was made through the isolation of Aspergillus from the secretion of the brain abscesses. The patient was treated with drainage of the abscesses and Amphotericin B. He presented a progressive regression of the radiological images (brain and pulmonary) over a period of 55 days. This report emphasizes the importance of combined anti-fungal therapy and surgical resection as a treatment for cerebral aspergilloma. Furthermore, an early initiation of therapy should improve the prognosis in such cases.

Aspergillus peritonitis: therapy, survival, and return to peritoneal dialysis

Peritonitis caused by fungi of the species Aspergillus is rare in peritoneal dialysis patients and is associated with high mortality. Four of the six reported survivors have been unable to resume peritoneal dialysis. We report the successful treatment of Aspergillus niger peritonitis with a combination of intravenous amphotericin B and peritoneal catheter removal in a patient on continuous ambulatory peritoneal dialysis (CAPD), and review previously reported cases of Aspergillus peritonitis. Our patient returned to CAPD after 2 months and has maintained good peritoneal transport 1 year after resumption of CAPD. The early recognition and aggressive treatment of peritonitis due to Aspergillus sp may allow eventual return to and successful maintenance of CAPD.

Amphotericin B followed by itraconazole in the treatment of disseminated fungal infections in neutropenic patients

The role of the new triazoles in the treatment of disseminated fungal infections in neutropenic patients is at present under scrutiny. Six neutropenic patients with disseminated fungal infections were treated with amphotericin B during neutropenia and itraconazole after bone marrow recovery. There were three pulmonary aspergillomas, one Aspergillus fumigatus sinusitis, one Fusarium-mycosis and one disseminated candidosis. Four patients were cured of the infection. This approach seems to be safe and effective in the treatment of disseminated fungal infections in neutropenic patients, with the advantages of low side-effects and the possibility of early discharge from hospital.

Itraconazole in the treatment of aspergillosis: a study of 16 cases

Itraconazole, a new triazole antifungal agent, has marked in vitro activity against filamentous fungi, particularly Aspergillus. We studied three groups of patients suffering from aspergillosis (16 cases): six affected with aspergilloma, three with allergic bronchopulmonary aspergillosis and seven with invasive aspergillosis. The survey consisted in clinical, radiological, mycological and serological evaluations with respect to drug plasma levels. Itraconazole was given at a dosage of 200-400 mg day-1 for periods ranging from 14 to 488 days. Out of the 16 patients, nine responded to therapy (recovery or improvement) and one failed to respond. Three patients improved but experienced relapses and three others could not be evaluated because of liver function disorders, so that treatment had to be stopped prematurely.

Experimental aspergillosis in guinea pigs: influence of itraconazole on fungaemia and invasive fungal growth

The guinea pig model of experimental aspergillosis was used to evaluate the efficacy of itraconazole 2.5 and 5 mg kg-1 in preventing the invasive phase of the disease when animals were already loaded with Aspergillus conidia. Evaluations were made by recording the survival rates, culturing fragments of nine organs, examining seven organs by means of histochemistry and immunohistochemistry (mAb EB-A1 to Aspergillus galactomannan) and by serological titration of galactomannan. The data indicate that itraconazole is highly effective in preventing true invasive aspergillosis. Serological evaluations of antigenaemia suggest that low titres may only reflect fungaemia, while titres of 1:8 and above are suggestive of invasive disease.

Low incidence of invasive fungal infections after bone marrow transplantation in patients receiving amphotericin B inhalations during neutropenia

The incidence of invasive fungal infections after bone marrow transplantation (BMT) was analyzed in 303 consecutive marrow graft recipients (allogeneic n = 271, autologous n = 27, syngeneic n = 5). All patients received inhalations with amphotericin B (10 mg twice daily) during neutropenia. The overall incidence of invasive fungal infections within the first 120 days after transplant was 3.6% (11/303; aspergillosis: 6; yeast infection: 5). Four of the 11 cases occurred early, and seven cases were observed after neutrophil recovery and discontinuation of amphotericin B inhalation treatment. Late infection was significantly associated with the development of acute graft-versus-host disease. Four of the 11 infections (early 2/4; late: 2/7) were observed in patients with a history of previous fungal infection. Other patient and treatment characteristics were not helpful in defining potential risk factors. In particular, the incidence of invasive fungal infections did not differ between patients with more or less strict reverse isolation measures. Occasional side effects such as initial mild cough and bad taste were rare, usually disappeared during continued administration, and were in no case the reason for discontinuation of treatment. These data suggest that aerosolized amphotericin B may be a useful, convenient, and efficient prophylactic antifungal regimen in BMT.

Efficacy of intravenous itraconazole against experimental pulmonary aspergillosis

The efficacy of intravenous itraconazole solubilized in hydroxypropyl-beta-cyclodextrin was assessed in a rat model of Aspergillus fumigatus pneumonia. Immunosuppressed rats were infected by intratracheal inoculation of A. fumigatus conidia. Intravenous administration of various doses of itraconazole was started immediately after infection and continued once a day for 7 days. A 10-mg dose of intravenous itraconazole per kg was as effective on survival as 1 mg of amphotericin B per kg daily (a survival rate of 100% in 28 days), while treatment with 1 mg/kg did not increase the survival rate. The 50% lethal dose of intravenous itraconazole given to immunosuppressed and uninfected rats for 7 days was 24.5 mg/kg/day. A microbiological assay to estimate accumulation in tissue after five daily intravenous administrations of itraconazole at 10 mg/kg showed that itraconazole and its active metabolites were present in the lungs for at least 6 h, reaching the MIC as previously described (B. Dupont and E. Drouchet, Rev. Infect. Dis. 9(Suppl. 1):71-76, 1987; A. Espinel-Ingroff, S. Shadomy, and R. J. Gebhart, Antimicrob. Agents Chemother. 26:5-9, 1984). Intravenous itraconazole was considered to be worth evaluating in clinical trials of aspergillosis.

Treatment of aspergillosis with itraconazole

OBJECTIVE

To review the role of itraconazole as oral therapy for the major infections caused by Aspergillus spp.: allergic bronchopulmonary aspergillosis, aspergilloma, and invasive aspergillosis.

DATA SOURCES

A MEDLINE search of articles published in the English language between 1986 and 1993 was used to identify relevant citations, including review articles. In addition, a search of the published abstracts of the past two Interscience Conferences on Antimicrobial Agents and Chemotherapy (ICAAC) was performed.

STUDY SELECTION

Clinical trials that evaluated itraconazole therapy in either allergic bronchopulmonary aspergillosis, aspergilloma, or invasive aspergillosis were critically reviewed. Trials were evaluated based upon entry criteria for the diagnosis of each type of aspergillosis, risk factors for the development of aspergillosis (neutropenia, transplant recipient, hematologic malignancy), prior antifungal chemotherapy, and dose and duration of itraconazole therapy.

DATA SYNTHESIS

Overall, the clinical trials of itraconazole therapy for aspergillosis are limited and of variable quality. In the treatment of allergic bronchopulmonary aspergillosis, itraconazole has been reported to prompt a reduction in corticosteroid dosage in selected patients. There have been no controlled trials of itraconazole as treatment for aspergilloma, but data from several open-label trials suggest that this agent may be of clinical benefit in aspergilloma, primarily as an alternative to surgery. The use of itraconazole for invasive aspergillosis has been evaluated in several trials, most often in patients who were intolerant to amphotericin B treatment. Response to oral itraconazole has generally been promising.

CONCLUSIONS

Although itraconazole offers promise for oral therapy against infections caused by Aspergillus spp., it should not presently be regarded as primary therapy for any of these diseases. Amphotericin B, in doses ranging from 1 to 1.5 mg/kg to a total dose of 1.5-4.0 g, should remain the treatment of choice in both aspergilloma and invasive aspergillosis. Itraconazole use should be restricted to patients who experience severe toxicity with amphotericin B therapy. Corticosteroids continue to be first-line therapy for allergic bronchopulmonary aspergillosis, with the use of itraconazole reserved for those patients who would benefit from a reduction in corticosteroid dose.

[Antimycotic agents. 20. Bioisoteric 6-arylpyrimidine derivatives]

Condensation of N-(2-hydroxyethyl)-N-methylguanidine-sulfate (1) with the beta-diketones 4a-e bearing 1-aryl substituents leads to the bioisosteric 2-[(2-hydroxyethyl)-methylamino]-6-arylpyrimidines 5a-e. Compounds 5a-c exhibit significant antimycotic in vivo and in vitro activities.