How should we manage a patient with invasive mucoromycosis who develops life-threatening reaction to amphotericin B? Report of two cases and literature review

Role of Amphotericin B in the Treatment of Mucormycosis

BACKGROUND

Regardless of the most recent inclusion of mold-active agents (isavuconazole and posaconazole) to antifungal agents against mucormycosis, in conjunction with amphotericin B (AMB) items, numerous uncertainties still exist regarding the treatment of this rare infection. The order Mucorales contains a variety of fungi that cause the serious but uncommon fungal illness known as mucormycosis. The moulds are prevalent in nature and typically do not pose significant risks to people. Immunocompromised people are affected by it.

OBJECTIVE

This article's primary goal is to highlight the integral role that AMB plays in this condition.

METHODS

Like sinusitis (including pansinusitis, rhino-orbital, or rhino-cerebral sinusitis) is one of the many signs and symptoms of mucormycosis. The National Center for Biotechnology Information (NCBI) produces a variety of online information resources for review articles on the topic-based mucormycosis, AMB, diagnosis of mucormycosis and the PubMed® database of citations and abstracts published in life science journals. These resources can be accessed through the NCBI home page at https://www.ncbi.nlm.nih.gov.

RESULTS

The article provides a summary of the pharmacological attributes of the various AMB compositions accessible for systemic use.

CONCLUSION

The article demonstrates the traits of the drug associated with its chemical, pharmacokinetics, stability, and other features, and illustrates their most useful characteristics for clinical application.

Mucormycosis

Mucormycosis is a rare but aggressive fungal disease that mainly affects patients with poorly controlled diabetes mellitus and those who are severely immunocompromised, including patients with hematological malignancies and solid organ transplant recipients. Early recognition of infection is critical for treatment success, followed by prompt initiation of antifungal therapy with lipid formulation amphotericin B. Posaconazole and isavuconazole should be used for stepdown and salvage therapy. Surgical debridement is key for tissue diagnosis and treatment and should be pursued urgently whenever possible. In addition to surgery and antifungal therapy, reverting the underlying risk factor for infection is important for treatment response.

Combination of amphotericin B and caspofungin in the treatment of mucormycosis

We report a case of invasive mucormycosis in 52 year-old woman. CT-scan and magnetic resonance imaging found a partial right sinus thrombosis associated with homolateral ethmoidal and maxillary sinusitis with submucosal inflammation. Histopathological examination of excised tissue was positive for mucormycosis. Our patient was treated by surgical debridement and a combination of amphotericin B and caspofungin, with a good outcome.

Mucormycosis: Early Identification of a Deadly Fungus [Formula: see text]

Mucormycosis is a rare invasive fungal infection that affects immunocompromised patients and is fatal when not identified and treated early. Diagnosis is often delayed as the symptoms are nonspecific and frequently mimic other common diseases. Pediatric patients with cancer are at risk for the infection; however, there is limited research that applies directly to the pediatric population. An understanding of the risk factors and clinical presentation of mucormycosis is crucial for the pediatric oncology provider to initiate the workup and provide prompt treatment. The gold standard for diagnosing mucormycosis is biopsy; however, the use of polymerase chain reaction is a novel tool that is being investigated. The mainstays of treatment are antifungal medications, surgery, and reversal of predisposing risk factors, although, new therapies are also emerging. This article will review the pathophysiology, clinical manifestations, and diagnostics of mucormycosis and will discuss current treatment and management strategies for the pediatric oncology clinician to allow for timely diagnosis and intervention to optimize patient outcomes.

Pharmacokinetics of antifungal drugs: practical implications for optimized treatment of patients

Introduction

Because of the high mortality of invasive fungal infections (IFIs), appropriate exposure to antifungals appears to be crucial for therapeutic efficacy and safety.

Materials and methods

This review summarises published pharmacokinetic data on systemically administered antifungals focusing on co-morbidities, target-site penetration, and combination antifungal therapy.

Conclusions and discussion

Amphotericin B is eliminated unchanged via urine and faeces. Flucytosine and fluconazole display low protein binding and are eliminated by the kidney. Itraconazole, voriconazole, posaconazole and isavuconazole are metabolised in the liver. Azoles are substrates and inhibitors of cytochrome P450 (CYP) isoenzymes and are therefore involved in numerous drug–drug interactions. Anidulafungin is spontaneously degraded in the plasma. Caspofungin and micafungin undergo enzymatic metabolism in the liver, which is independent of CYP. Although several drug–drug interactions occur during caspofungin and micafungin treatment, echinocandins display a lower potential for drug–drug interactions. Flucytosine and azoles penetrate into most of relevant tissues. Amphotericin B accumulates in the liver and in the spleen. Its concentrations in lung and kidney are intermediate and relatively low myocardium and brain. Tissue distribution of echinocandins is similar to that of amphotericin. Combination antifungal therapy is established for cryptococcosis but controversial in other IFIs such as invasive aspergillosis and mucormycosis.

Breaking the Mold

Objective: To review the current literature for the pathogenesis of mucormycosis, discuss diagnostic strategies, and evaluate the efficacy of polyenes, triazoles, and echinocandins as pharmacological treatment options. Data Sources: An electronic literature search was conducted in PubMed using the MESH terms Rhizopus, zygomycetes, zygomycosis, Mucorales and mucormycosis, with search terms amphotericin B, micafungin, anidulafungin, caspofungin, extended infusion amphotericin B, liposomal amphotericin B, combination therapy, triazole, posaconazole, isavuconazole, diagnosis, and clinical manifestations.Study Selection and Data Extraction: Studies written in the English language from January 1960 to March 2016 were considered for this review article. All search results were reviewed, and the relevance of each article was determined by the authors independently. Data Synthesis: Mucormycosis is a rare invasive fungal infection with an exceedingly high mortality and few therapeutic options. It has a distinct predilection for invasion of endothelial cells in the vascular system, which is likely important in dissemination of disease from a primary focus of infection. Six distinct clinical syndromes can occur in susceptible hosts, including rhino-orbital-cerebral, pulmonary, gastrointestinal, cutaneous, widely disseminated, and miscellaneous infection. Conclusion: Diagnosis of mucormycosis is typically difficult to make based on imaging studies, sputum culture, bronchoalveolar lavage culture, or needle aspirate. Surgical debridement prior to dissemination of infection improves clinical outcomes. Surgery combined with early, high-dose systemic antifungal therapy yields greater than a 1.5-fold increase in survival rates. The Mucorales are inherently resistant to most widely used antifungal agents. Amphotericin B is appropriate for empirical therapy, whereas posaconazole and isavuconazole are best reserved for de-escalation, refractory cases, or patients intolerant to amphotericin B.