Outcome of transcutaneous retrobulbar injection of liposomal amphotericin B in post-COVID-19 rhino-orbito-cerebral mucormycosis: Our experience

New and emerging roles for inhalational and direct antifungal drug delivery approaches for treatment of invasive fungal infections

INTRODUCTION

The rising prevalence of difficult-to-treat, deep-seated invasive fungal diseases (IFD) has led to high mortality. Currently available antifungal treatments, administered predominantly orally or intravenously, may not sufficiently penetrate certain body sites, and/or are associated with systemic toxicity. Little is known about how to position alternative administration approaches such as inhalational and direct drug delivery routes.

AREAS COVERED

This review provides an updated overview of unconventional drug delivery strategies for managing IFD, focusing on inhalational (to target the lungs) and direct delivery methods to the central nervous system, bone/joint, and eyes. Novel compounds (e.g. opelconazole) and existing antifungals with innovative drug delivery systems currently undergoing clinical trials and/or used off-label in the clinical setting are discussed.

EXPERT OPINION

For both inhalational agents and direct delivery approaches, there are similar challenges that include the absence of: approved formulations for specific administration routes, delivery vehicles that are simple and safe to use whilst maintaining potency and efficiency of delivery, animal models suitable for investigating pharmacokinetic/pharmacodynamic profiles of inhaled antifungals, and consensus on the composite endpoints and intervals for of follow-up in clinical trials. To meet these challenges, cooperation of all stakeholders in drug development and regulation is required.

Transcutaneous Retrobulbar Amphotericin B Injection for Invasive Fungal Sinusitis with Orbital Involvement: A Systematic Review

BACKGROUND

Orbital involvement of invasive fungal sinusitis (IFS) is an ominous prognostic marker that should prompt rapid intervention. Transcutaneous retrobulbar administration of amphotericin B (TRAMB) is an off-label adjunctive treatment that can increase drug penetrance into diseased orbital tissue. To date, there is a lack of consensus regarding the use of TRAMB for treatment of IFS with orbital involvement.

OBJECTIVE

This systematic review aims to synthesize the indications, efficacy, and potential complications of TRAMB.

METHODS

PubMed, EMBASE, and Web of Science databases were probed for systematic review. Article search was conducted through June 2023 using the keywords "invasive fungal sinusitis," "invasive fungal rhinosinusitis," "rhino-orbital mucormycosis," "rhinosinusitis," "orbital," "retrobulbar," and "amphotericin."

RESULTS

In suitable cases as determined by radiologic and clinical evaluation, TRAMB administration has the potential to improve orbital salvage rates and improve versus stabilize visual acuity. Treatment complications are more likely with deoxycholate than with liposomal amphotericin formulations. The existing literature describing use of TRAMB is limited due to its retrospective nature, but the increase in IFS cases since 2020 due to the COVID pandemic has broadened the literature.

CONCLUSIONS

TRAMB is an effective adjunctive treatment in IFS with mild-to-moderate orbital involvement when used in combination with standard of care debridement, systemic antifungal therapy, and immunosuppression reversal. Prospective longitudinal studies and multi-institutional randomized trials are necessary to determine the definitive utility of TRAMB.

Combination endoscopic surgical debridement and transcutaneous retrobulbar amphotericin B for acute rhino-orbital-cerebral aspergillosis

PURPOSE

To report a case of acute rhino-orbital-cerebral aspergillosis with aggressive intracranial and orbital extension co-managed medically and surgically with endoscopic sinus debridement and multiple retrobulbar injections of amphotericin B.

OBSERVATIONS

A 70-year-old male patient presented via external transfer with headaches and left ophthalmoplegia concerning for severe complicated sinusitis with intracranial and left orbital spread. His history is notable for a simultaneous heart-kidney transplant three years prior on chronic immunosuppression. Ophthalmologic examination revealed complete ophthalmoplegia in the left eye with no light perception concerning for a left orbital apex syndrome. The patient was taken to the operating room twice for endoscopic sinus debridement and three separate retrobulbar injections of amphotericin B. Fungal cultures from surgical specimens grew isolated Aspergillus fumigatus. Patient's symptoms gradually improved and repeat MRI demonstrated resolution of pansinusitis, sparing left eye exenteration.

CONCLUSIONS AND IMPORTANCE

Multidisciplinary management of invasive fungal rhinosinusitis in the setting of profound immunosuppression poses a significant challenge. While surgical debridement remains the cornerstone approach, the achievable reduction in disease burden may be augmented by targeted retrobulbar antimicrobials.

Local injection of amphotericin B: novel use in the treatment of fungal maxillary sinusitis

This report highlights the role of local amphotericin B (AMB) injection in cases of maxillary mucormycosis. The COVID-19 pandemic has resulted in a dramatic rise in the number of rhino-orbital mucormycosis cases. Although extensive surgical debridement remains the gold standard treatment, tissue salvage is desirable. The cases of two patients treated with local AMB are reported here, indicating that early intervention for maxillary fungal sinusitis in the form of local AMB may avoid the need for more invasive treatment.

Orbital Mucormycosis: Understanding the Deadly Fungus Sweeping the Globe

Introduction Mucormycosis (black fungus) is a rare opportunistic fungal infection commonly affecting immunocompromised individuals. There has been a surge in the number of these cases during the second wave of the coronavirus disease 2019 (COVID-19) in India. Mucormycosis has been reported to occur within a week or a few weeks post-recovery from COVID-19. The most common clinical manifestation of mucormycosis is rhino-orbital-cerebral mucormycosis (ROCM). At our tertiary care center, we initiated a prospective study to identify risk factors, study ocular manifestations, and explore medical and surgical management of orbital mucormycosis patients in the post-COVID-19 era. Material and methods This is a detailed description of a prospective observational hospital-based study. The study included 148 patients who presented with ROCM. A detailed history was taken regarding the complaint, duration, and associated risk factors. Systemic, local, and complete ophthalmic examinations were done that included assessment of extraocular movements, visual acuity, slit-lamp examination, and fundus examination. All data were recorded separately for each patient in a pre-decided proforma. Result The study group consisted of 148 patients. In our study, the highest association was with COVID-19-positive status (68.24%), out of which 57 (56.43%) were on oxygen support. Diabetes mellitus contributed next to COVID-19 with 86 (58.10%) patients with a positive history of diabetes. Seventy-one (47.97%) patients were on steroids, out of which 68 (67.32%) were COVID-19-positive and the rest (23%) were on steroids due to various systemic reasons. Rhinomaxillary involvement was present (51%). Out of 63 patients with orbital involvement, 16 (25.39%) presented bilaterally and 47 showed unilateral orbital involvement more on the right side (42.85%). The predominant location of orbital involvement was the orbital apex. The most common symptom seen in our study was nasal discharge (86.5%), and ophthalmoplegia was the most common sign. Conclusion Corticosteroids should be used with caution to prevent negative impact and potential ROCM. Good glycemic and metabolic control is crucial for treatment. Management of mucormycosis involves surgical debridement, antifungal agents, and retrobulbar amphotericin B injections. Early diagnosis and aggressive treatment are essential for success. Orbital exenteration may be necessary for advanced stages, while conservative approaches may work for earlier stages. Patient counseling is needed for cosmetic rehabilitation. A multidisciplinary approach involving various specialists is necessary.

Clinical Phenotypes of COVID-19 Associated Mucormycosis (CAM): A Comprehensive Review

A mucormycosis surge was reported during the COVID-19 pandemic in India. A literature search until 14 July 2022, with the aim of updating COVID-19-associated mucormycosis (CAM), identified 663 studies and 88 met inclusion criteria (8727 patients). India reported 8388 patients, Egypt 208 and Europe 40. Rhino-orbito-cerebral mucormycosis (ROCM) was identified among 8082 (98.3%) patients, followed by 98 (1.2%) with pulmonary. In India, 82.6% of patients had diabetes mellitus, with 82% receiving corticosteroids. In Europe, 75% presented pulmonary CAM, 32.5% had diabetes and 40% were immunocompromised. CAM was identified at a median of 17.4 days (IQR 7.5 days) post COVID-19 diagnosis, and PCR was performed in five studies. Rhino-orbital invasion is clinically obvious, while cerebral involvement presents with cavernous sinus thrombosis, meningitis and cerebrovascular disease. Symptoms of pulmonary CAM usually overlap with severe COVID-19 pneumonia. High-dose liposomal Amphotericin B (and early surgical debridement in ROCM) are the mainstay of therapy. The median mortality rate was estimated to be 21.4% (IQR 31.9%), increased by the presence of pulmonary (80% (IQR 50%) or cerebral involvement (50% (IQR 63.9%). In summary, different CAM clinical phenotypes need to be distinguished, influenced by geographical presentation. Opportunities exist for diagnosis and therapy optimization, based on earlier high-dose antifungal therapy, early source control, strict glycemic control and restriction of steroids to COVID-19 patients with oxygen requirements.

Rhino-orbital mucormycosis

PURPOSE OF REVIEW

The current article will update and review the clinical and radiological manifestations and management of rhino-orbital mucormycosis (ROM).

RECENT FINDINGS

There has been an increase in cases of ROM worldwide, especially in India. Immunosuppression (especially diabetes mellitus) is a known predisposing risk factor for ROM. Delayed diagnosis and treatment of ROM can be vision or life-threatening. This article reviews the clinical and radiologic features, treatment, and prognosis of ROM with special emphasis on new and emerging therapies.

SUMMARY

ROM is an angioinvasive fungal infection that affects the sinuses and orbits and may present to ophthalmologists. Clinicians should have a high index of suspicion for ROM, especially in patients with poorly controlled diabetes mellitus or other immunosuppression. Corticosteroid treatment (including the recent COVID-19 pandemic) may be a predisposing risk factor for ROM.

Retrobulbar Injection of Amphotericin B in Patients With COVID-19 Associated Orbital Mucormycosis: A Systematic Review

PURPOSE

Following COVID-19 infection a rising count of rhino-orbito-cerebral mucormycosis is observed, requiring orbital exenteration, a disabling lifetime affecting surgery. One of the potential interventions for globe salvage in these patients is retrobulbar injections of amphotericin B. This study was conducted to review protocols, outcomes, and side effects of retrobulbar injection of amphotericin B in patients with COVID-19 associated rhino-orbito-cerebral mucormycosis (CAM).

METHODS

The PubMed, Scopus, Web of Science, and Embase databases were searched using a comprehensive string of relevant keywords. All English studies with the confirmed diagnosis of CAM infection were included. We excluded all studies in which retrobulbar injection of amphotericin B was not implemented in any of the patients or there was a lack of clarified and detailed data about this procedure among participants.

RESULTS

A total of 647 cases had a history of retrobulbar injection(s) of amphotericin B in 13 reviewed studies with 3,132 subjects of CAM. The most common protocol was the retrobulbar injection of 1 ml of 3.5 mg/ml liposomal amphotericin B for 3 doses daily or on alternate days. We discerned that the globe salvage rate was 95.0% in eyes with a history of retrobulbar injection(s). The total rate of orbital exenteration was 14.9%, regardless of the history of retrobulbar injection of the drug. Other outcomes of this intervention were vision salvage and reduced major ophthalmic complaints, including pain, swelling, chemosis, ptosis, and ophthalmoplegia. The side effects of this intervention were not serious, and most of them were transient. They included swelling at the injection site, restriction of ocular motilities, exacerbation of orbital inflammation, and even intensification of visual impairment in a few cases.

CONCLUSIONS

Retrobulbar injection of amphotericin B should be considered a nearly safe and protective intervention against orbital exenteration in patients with CAM. It may also be effective in saving vision. Since the effectiveness of orbital exenteration in the survival of patients is not ascertained, retrobulbar injections can be considered an alternative intervention.

Outcomes of Transcutaneous Retrobulbar Amphotericin B in Rhino-Orbital-Cerebral Mucormycosis Among Patients Recovering From COVID-19: A Preliminary Experience

Background

In this study, we aimed to assess the outcomes of transcutaneous retrobulbar injection of amphotericin B (TRAMB) in rhino-orbital-cerebral mucormycosis (ROCM) among patients recovering from coronavirus disease 2019 (COVID-19).

Methodology

This retrospective study was conducted at a tertiary care center in eastern India from May 29th to July 31st, 2021, and included post-COVID-19 patients admitted with stage 3 and 4a ROCM who underwent TRAMB. The details of the ophthalmic examination, laboratory investigations, and radiological examination were retrieved from patients records. Patients were given TRAMB (3.5 mg/mL) on alternate days till they underwent debulking surgery and resumed from the second postoperative day alternatively till the patients showed clinical stabilization or improvement.

Results

In total, 45 eyes of 41 patients were included in the study. The median number of injections given was six (minimum = 3; maximum = 10). Following was the distribution of number of injection needed in each eye: eight eyes (three injections), six eyes (four injections), seven eyes (five injections), three eyes (six injections), eight eyes (seven injections), 11 eyes (eight injections), and one eye had received nine and ten injections each. Overall, 21/32 (65.62%) eyes had improvement in proptosis whereas 9/32 (28.12%) had improvement in ptosis. Six patients had improvement in extraocular movement. In total, 25 eyes had no improvement whereas seven eyes had improvement in vision. Four eyes underwent exenteration. All nine patients with limited orbital disease had good improvement with fewer injections (median = 4). None of the patients undergoing TRAMB had an intracranial extension of disease. Moreover, 8.88% (4/45) of the eyes had post-TRAMB transient inflammation which resolved without any intervention. Finally, 3/41 of the patients died.

Conclusions

TRAMB can be considered as an useful therapeutic adjunct in managing ROCM. Further, it can halt the progression of the disease while awaiting definitive surgical intervention.