Management of cerebral azole-resistant Aspergillus fumigatus infection: A role for intraventricular liposomal-amphotericin B

Early Experiences with Intrathecal Administration of Amphotericin B Liposomal Formulation at a Neurosurgical Center

BACKGROUND

Intrathecal administration of amphotericin B represents an important adjunctive therapy for management of severe fungal meningitis. Intrathecal preparations have traditionally used amphotericin B deoxycholate. Liposomal amphotericin B is an alternative formulation with good clinical outcomes as systemic therapy, but scant data exist investigating intrathecal use.

OBJECTIVE

The aim of this exploratory study was to evaluate outcomes following intrathecal administration of liposomal amphotericin B for treatment of severe fungal meningitis.

METHODS

A national shortage of amphotericin B deoxycholate necessitated revision of institutional protocols at a southwestern neurosurgical center in Spring 2023. A starting intrathecal daily dose of 0.125-0.5 mg liposomal amphotericin B was recommended (dependent on insertion device), with 0.125-0.25 mg slow titration every 48 h and up to a 2 mg maximum daily dose.

RESULTS

Four cases of fungal meningitis treated with adjunctive intrathecal amphotericin B liposomal formulation were reviewed. This included three cases of coccidioidal meningitis and one case of presumed Fusarium solani meningitis following an outbreak. All patients had initial disease improvement following initiation of intrathecal amphotericin B and were able to tolerate long-term therapy. One coccidioidal meningitis patient expired of neurologic complications shortly after being moved from the intensive care unit (ICU) to a floor unit. All other patients were successfully discharged from the hospital. New headache was the only reported adverse effect, which was managed with dose reduction and did not require therapy discontinuation.

CONCLUSIONS

Liposomal amphotericin B may be feasibly administered intrathecally for the adjunctive treatment of severe fungal meningitis.

Successful Multimodal Therapy with Intracerebral Liposomal Amphotericin B and Systemic High-Dose Isavuconazole in Proven Disseminated Aspergillosis

We report the case of a 32-year-old man receiving chemotherapeutics for an acute B-lymphoblastic leukemia who developed proven cerebral and pulmonary aspergillosis with Aspergillus flavus. Because of progressive fungal disease with neurological deterioration despite adequate systemic antifungal therapy and surgical debridement, intracerebral administration of liposomal amphotericin B was initiated at 5 mg twice weekly. This led to improvement of the cerebral infection. Surgical debridement of a pleural Aspergillus empyema was necessary, and pleural trough level of isavuconazole was found to be subtherapeutic despite adequate blood trough levels, which led us to increase the dose of isavuconazole. We conclude that intralesional amphotericin B might be beneficial at 5 mg twice weekly in cerebral aspergillosis if systemic antifungals and surgical debridement fail. In Aspergillus empyema, measurement of pleural isavuconazole trough levels should be considered.

Intraventricular CNS aspergillosis in a patient with prior history of COVID-19: Case report and review of literature

Introduction and importance

Although some immunocompetent patients have developed invasive aspergillosis, the vast majority of cases are seen in immunocompromised patients. COVID-19 infection has been proposed to cause immune dysfunction or suppression, which predisposes patients to fungal co-infections such as mucormycosis and aspergillosis.

Case presentation

A 58-year-old woman was admitted to the hospital with confusion, dysarthria, and loss of consciousness. The patient had a 1-month prior history of severe COVID-19 infection. A computerized tomography (CT) scan and a magnetic resonance imaging (MRI) revealed an intraventricular lesion with perilesional edema and a significant midline shift, which was initially thought to be an intraventricular tumor. Following a posterior parietal craniotomy, the lesion was resected via a transcortical approach from the posterior parietal region to the right lateral ventricle. Histopathological findings confirmed intraventricular aspergillosis (IVA). The patient was treated with intravenous amphotericin B for two months and discharged with oral variconazole for 4 months.

Discussion

Covid-19 infections can result in- dissemination of fungal diseases such as aspergillosis. As a minor component of cerebral aspergillosis with a poor prognosis, intraventricular aspergillosis necessitates prompt treatment, which includes surgical resection and the administration of anti-fungal medications.

Conclusion

Infection with COVID-19 causes immune dysfunction, which leads to fungal co-infection, including CNS aspergillosis. As a result, all COVID-19 patients who present with acute neurologic symptoms should have CNS aspergillosis considered in their differential diagnosis.

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Infection with COVID-19 can cause immune dysfunction, which may lead to fungal co-infection, including CNS aspergillosis.

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Workup of COVID-19 patients with acute neurologic symptoms should be broad and include fungal infectious.

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Patients with CNS aspergillosis should receive prompt treatment because these cases have poor prognosis and can be fatal.

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.

Conventional Antifungals for Invasive Infections Delivered by Unconventional Methods; Aerosols, Irrigants, Directed Injections and Impregnated Cement

The administration of approved antifungals via unapproved formulations or administration routes (such as aerosol, direct injection, irrigation, topical formulation and antifungal-impregnated orthopedic beads or cement) may be resorted to in an attempt to optimize drug exposure while minimizing toxicities and/or drug interactions associated with conventional (systemic) administrations. Existing data regarding such administrations are mostly restricted to uncontrolled case reports of patients with diseases refractory to conventional therapies. Attribution of efficacy and tolerability is most often problematic. This review updates prior published summaries, reflecting the most recent data and its application by available prevention and treatment guidelines for invasive fungal infections. Of the various dosage forms and antifungals, perhaps none is more widely reported than the application of amphotericin B-containing aerosols for the prevention of invasive mold infections (notably Aspergillus spp.).

Azole resistance in Aspergillus species: promising therapeutic options

INTRODUCTION

Azoles are the first-line antifungal agents used for the treatment of Aspergillus infection. There is an increasing concern for azole resistance all over the world mainly from agricultural fungicide use. Choosing safe and effective antifungal regimens has become a challenge.

AREAS COVERED

Here, the authors review the epidemiology, mechanisms, and detection of azole resistance along with management options for azole-resistant Aspergillus infection, including new antifungal agents under development.

EXPERT OPINION

Routine global epidemiological surveillance is required to understand azole resistance prevalence. Azole-resistant Aspergillus infections are associated with high mortality. No good therapeutic options are currently available. High index of suspicion of resistance is required if a patient is not responding to 4-7 days of azole therapy, particularly in the areas of resistance. Susceptibility testing for Aspergillus is not routinely available in many parts of the world, which makes it difficult to diagnose azole resistance in Aspergillus infection. There are several new antifungal classes with novel mechanisms of action; clinical trials are ongoing.

Aspergillus fumigatus and pan-azole resistance: who should be concerned?

PURPOSE OF REVIEW

Although clinical outcomes in the treatment of aspergillosis have markedly improved with the availability of newer triazoles, the development of resistance to these antifungals, especially in Aspergillus fumigatus, is a growing concern. The purpose of this review is to provide an update on azole resistance mechanisms and their epidemiology in A. fumigatus, the clinical implications of azole resistance, and to discuss future treatment options against azole-resistant aspergillosis.

RECENT FINDINGS

Resistance may develop through either patient or environmental azole exposure. Environmental exposure is the most prevalent means of resistance development, and these isolates can cause disease in various at-risk groups, which now include those with influenza, and potentially COVID-19. Although current treatment options are limited, newer therapies are in clinical development. These include agents with novel mechanisms of action which have in vitro and in vivo activity against azole-resistant A. fumigatus.

SUMMARY

Azole-resistant A. fumigatus is an emerging threat that hampers our ability to successfully treat patients with aspergillosis. Certain geographic regions and patient populations appear to be at increased risk for this pathogen. As new patient groups are increasingly recognized to be at increased risk for invasive aspergillosis, studies to define the epidemiology and management of azole-resistant A. fumigatus are critically needed. While treatment options are currently limited, new agents under clinical development may offer hope.