Current treatments against mucormycosis and future directions

Sensitivity and specificity of immunohistochemistry for the diagnosis of filamentous fungal infections

OBJECTIVES

Many fungal species share overlapping morphologic features in tissue sections, preventing reliable identification and optimal treatment. We sought to determine whether immunohistochemistry (IHC) using a panel of commercially available antibodies could effectively distinguish between fungi commonly encountered in anatomic pathology specimens.

METHODS

Anti-Aspergillus, anti-Rhizopus, and anti-Candida IHC was performed on formalin-fixed, paraffin-embedded tissue sections from 24 cases with fungal infections identified by culture or sequencing (including 4 polyfungal infections).

RESULTS

Anti-Aspergillus IHC was positive in 6 of 6 Aspergillus and focally in 1 of 4 Candida species infections and negative in all cases of Fusarium, Scedosporium, Rhizopus, and Mucor species, yielding overall sensitivity of 100% and specificity of 95%. Anti-Rhizopus IHC was positive in 4 of 4 Rhizopus and 1 of 3 Mucor species infections and negative in all other cases, with a sensitivity of 71% and a specificity of 100%. Anti-Candida IHC was positive in 4 of 4 Candida species infections and showed some cross-reactivity in all other cases, resulting in 100% sensitivity and 0% specificity.

CONCLUSIONS

Anti-Aspergillus IHC was highly sensitive and specific in its ability to distinguish Aspergillus from other similar-appearing hyaline molds, including Fusarium and Scedosporium species. Anti-Rhizopus IHC was moderately sensitive and highly specific, while anti-Candida IHC was highly sensitive but had minimal specificity.

Rhino-orbito-cerebral mucormycosis after allogeneic hematopoietic stem cell transplantation for very severe aplastic anemia in a child: a case report

Rhino-orbito-cerebral mucormycosis (ROCM) is a rare and life-threatening fungal infection that predominantly affects immunocompromised individuals, such as those undergoing hematopoietic stem cell transplantation (HSCT). This report describes the case of a 10-year-old girl with very severe aplastic anemia (VSAA) who underwent an haploidentical HSCT from her father. She initially achieved successful engraftment with a donor chimerism rate of 98.25% on day 60. However, on day 65 post-transplant, she developed severe right-eye pain, progressive swelling, and visual impairment. Comprehensive evaluations, including contrast-enhanced magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) analysis, revealed extensive orbital and cerebral involvement consistent with ROCM. Intensive antifungal therapy with liposomal amphotericin B and posaconazole, along with endoscopic surgical debridement of the infected sinuses and orbital regions, was initiated. Post-treatment MRI scans demonstrated a significant reduction in cerebral edema and other abnormalities, while repeated CSF analyses confirmed the absence of fungal elements. This case underscores the critical need for early diagnosis and aggressive management of ROCM in immunocompromised patients, particularly following HSCT.

Preoperative Administration of Amphotericin B in Orbital Mucormycosis Management: A Case Report

This case report presents a 29-year-old male with diabetes mellitus who developed rhino-orbito-cerebral mucormycosis (ROCM) that was successfully treated with liposomal amphotericin B orbital injections. Despite emergent endoscopic debridement, the patient's disease progressed intracranially and intraorbitally, but he declined further surgical intervention. Subsequently, due to rapid acute vision loss, we initiated transcutaneous retrobulbar amphotericin B (TRAMB) injections. Following these injections, visual acuity, motility, and intraorbital fungal burden improved despite intracranial progression. This report highlights the benefits of TRAMB administration in aggressive fungal infections and explores the mechanisms behind its effectiveness, particularly in globe preservation. By targeting the infection in an area with a relatively robust blood supply, TRAMB reduces surgical difficulty and improves overall outcomes.

Intra-abdominal Mucormycosis in an Immunocompetent Host: A Rare Presentation and Literature Review

Mucormycosis is a severe, opportunistic infection caused by Mucorales, a taxonomical group of thermotolerant fungi primarily affecting the immunocompromised. Intra-abdominal involvement in mucormycosis is a rare entity, particularly in immunocompetent individuals. We present a fatal case of gallbladder and renal mucormycosis in an immunocompetent female, leading to septic shock and death. The diagnosis was confirmed via histopathology following cholecystectomy for suspected gangrenous cholecystitis and open right nephrectomy due to kidney infarction. Quantitative polymerase chain reaction of the tissue identified the presence of Apophysomyces ossiformis. The clinical picture was confounded by ongoing sepsis due to a Klebsiella pneumoniae-infected retroperitoneal hematoma, non-specific imaging findings, and the absence of traditional risk factors for mucormycosis, leading to a delayed diagnosis. Despite surgical debridement, initiation of liposomal amphotericin B with posaconazole, and aggressive treatment in the intensive care unit, the patient succumbed to complications of mucormycosis. Despite adequate antibiotic coverage, this case underscores the importance of considering Mucorales infection in otherwise immunocompetent patients with a deteriorating clinical condition. Early diagnosis and appropriate intervention are essential in enhancing mucormycosis survivability, though mortality rates remain high in severe cases.

The Black Fungus: A Rare Case of Pulmonary Mucormycosis

Background

Mucormycosis, commonly known as the "black fungus," is a severe infection affecting multiple organ systems, including the skin, brain, lungs, and gastrointestinal tract. This case report is focused on pulmonary mucormycosis, which is frequently observed in organ transplant recipients. Diagnostic challenges arise from nonspecific symptoms.

Case Presentation

Our case involved a 61-year-old male with a history of renal transplantation. The patient initially presented with a persistent cough and bloody sputum and was treated unsuccessfully for a presumed fungal infection. A lung biopsy confirmed pulmonary mucormycosis, emphasizing the heightened vulnerability of immunocompromised individuals.

Conclusion

This case highlights the intricate nature of mucormycosis diagnosis and management, particularly in post-organ transplantation patients. It underscores the importance of awareness and collaboration among medical specialists, including infectious disease experts, pulmonologists, and transplant teams, to optimize outcomes in the face of this life-threatening infection.

An Immunocompetent 56-Year-Old Woman With Multiple Enlarged Lymph Nodes and Recurrent Fevers

CASE PRESENTATION

A 56-year-old woman was admitted to our hospital, presenting with a history of recurrent fevers persisting for over 2 months. The febrile episode was self-limiting, accompanied by cough without significant expectoration, with the fever predominantly manifesting during the afternoon and evening hours. Furthermore, there were no concurrent symptoms indicative of chest tightness, wheezing, dyspnea, or hemoptysis. A CT scan in a local hospital demonstrated multifocal lymphadenopathy in the mediastinum and bilateral supraclavicular regions. The patient had neither a history of tobacco usage nor of alcohol consumption. Furthermore, there was no familial history of oncologic conditions. The patient's medical records revealed no evidence of hypertension, diabetes mellitus, coronary artery disease, infectious diseases, or immunologic disorders.

Sjogren's Syndrome Complicated by Naso-Orbito-Cerebral Mucormycosis: A Case Report

Background: Sjogren's syndrome (SS) is a chronic inflammatory autoimmune disease characterized by exocrine gland dysfunction. Mucormycosis is a rare yet life-threatening opportunistic fungal infection caused by Mucor species, with a high mortality rate. In patients undergoing long-term immunosuppressive therapy or corticosteroid use, especially when compounded by conditions such as diabetes or hyperlipidemia, Mucor can become pathogenic. Medical Record Description: We retrospectively analyzed the clinical data of a patient with Sjogren's syndrome complicated by rhinocerebral mucormycosis, focusing on its clinical presentation and progression. The patient was admitted to the hospital 20 days prior with symptoms of a "nasal infection" caused by a furuncle on the nose. The condition progressively worsened, resulting in nasofacial skin ulceration and necrosis, with black eschar formation around the affected area. Upon admission, comprehensive evaluations, including rapid histopathological and fungal tests, confirmed the diagnosis of mucormycosis. Despite surgical intervention under general anesthesia and antifungal therapy, the clinical outcome was ultimately fatal. Conclusion: Mucor infections commonly occur in patients with immunodeficiency and severe underlying diseases. The clinical manifestations are diverse, often presenting with skin tissue necrosis and the formation of black eschar. Fungal culture and histopathological examination remain the gold standards for diagnosing mucormycosis, while imaging studies are crucial for evaluating the extent of fungal dissemination and bone involvement. Given the rapid progression of the disease, early diagnosis and prompt treatment are critical for improving survival rates.

The Importance of MRI in the Early Diagnosis of Acute Invasive Fungal Rhinosinusitis

Acute invasive fungal rhinosinusitis (AIFR) is a rare, severe, and life-threatening opportunistic infection associated with high mortality and morbidity. Rapid and accurate diagnosis and treatment are crucial for survival and effective disease management. Diagnosing AIFR is challenging because no single pathognomonic feature exists other than surgical biopsy showing fungal angioinvasion and necrosis. This narrative review focuses on the diagnostic challenges and pitfalls, emphasizing the critical clinical value of magnetic resonance imaging (MRI) for early diagnosis of AIFR. It includes selected cases that illustrate the significance of MRI. When AIFR is suspected, clinical symptoms, nasal endoscopy, blood samples, and facial computed tomography all provide non-specific information. In contrast, MRI can identify signs of devitalized sinonasal mucosa consistent with AIFR. The absence of mucosal enhancement on T1-weighted images, combined with restricted diffusivity, are characteristic MRI features of AIFR. The cases presented underscore the usefulness of MRI in supporting clinical suspicion of AIFR and accurately determining its topography, thereby guiding early surgical biopsies and debridement. In suspected cases of AIFR, MRI serves as a valuable supplementary, non-invasive tool to help determine whether prompt surgical biopsy or debridement is necessary, thereby enhancing early diagnosis and improving survival rates. Therefore, the threshold for conducting an MRI in these cases should be low.

Appendiceal Perforation and Abdominal Wall Infection Caused by Invasive Mucormycosis in a Child with Acute Leukemia

Gastrointestinal mucormycosis is one of the most difficult forms of the disease to diagnose due to its lack of specific clinical features. It is extremely rare to observe gastrointestinal mucormycosis in pediatric acute leukemia patients undergoing chemotherapy. In this report, we describe a case of a child with acute leukemia who developed invasive mucormycosis, leading to appendiceal perforation and abdominal wall infection. Initially, surgical intervention was delayed due to concerns over exacerbating bone marrow suppression, which ultimately resulted in the progression of the intra-abdominal infection. However, after thorough debridement of the abdominal wall infection and treatment with liposomal amphotericin B, the patient gradually recovered. This case highlights the importance of early and complete debridement of abdominal wall infections and intra-abdominal abscesses to prevent the further spread of mucormycosis, shorten the course of the disease, and improve outcomes.

Use of isavuconazole in mucormycosis: a systematic review

BACKGROUND

Mucormycosis is an opportunistic fungal infection which is associated with poor prognosis. Only a few antifungals are available in the arsenal against mucormycosis. The global guidelines for diagnosing and managing mucormycosis recommend high doses of liposomal amphotericin B (LAmB) as the first-line treatment. Isavuconazole is another potential treatment option for mucormycosis.

MAIN BODY

This systematic review aims to consolidate and analyse existing evidence concerning the efficacy and safety of isavuconazole in treating mucormycosis alone or in combination with LAmB. For data aggregation, comprehensive searches were conducted across various electronic databases, such as PubMed, Science Direct, Trip, Google Scholar, the Cochrane Library, and Open-Gray. Furthermore, we explored the gray literature, employing tailored keywords. The reference lists of the selected articles were scrutinized to identify additional pertinent publications. Articles reporting any studies, case series, or case reports on any form of mucormycosis exclusively involving human subjects published in English were included. There were no time restrictions involved. We extracted crucial data, such as publication year, country, disease form, isavuconazole dosage, frequency, duration, overall outcomes, and reported adverse effects. A total of 31 articles, which included four case series, 24 case reports, one open-label trial, one randomized controlled trial, and one non-interventional registry study, were included in the final analysis. 135 adult patients and 14 children were treated with isavuconazole as primary monotherapy, primary combination therapy, nonprimary monotherapy, or nonprimary combination therapy. The mortality rate following LAmB monotherapy, amphotericin B plus azole, amphotericin B followed with azole, posaconazole only and isavuconazole only was 32%, 6.6%, 13.7%, 17.2% and 24.6%, respectively. The heterogeneity of the studies did not allow for a comparison of the different treatment strategies (primary mono- vs. primary combination, etc.).

SHORT CONCLUSION

The use of isavuconazole in combination therapies during the acute phase via intravenous administration alongside LAmB or other triazoles, followed by long-term monotherapy via the oral route, has yielded promising recovery rates. Adverse events associated with the use of isavuconazole are infrequently reported.

Mucormycosis Infection in Lung Transplant Patients: Experience in Andalusia, Spain

INTRODUCTION

Mucorales infections in the airways of lung transplant (LT) patients are rare but have a rising incidence in transplanted lungs.

OBJECTIVE

We present our experience with LT in immediate postoperative infections due to mucormycosis.

METHODS

Review of 767 LT performed in Andalusia between 2000 and 2023 identifying Mucorales through microbiological results and histological findings.

RESULTS

The incidence of Mucorales was less than 1% of all LTs performed at our institution but resulted in 100% mortality. In our series, all cases underwent LT for chronic obstructive pulmonary disease. They presented with pulmonary infection that progressed to disseminated infection. Major associated risk factors included prior corticosteroid treatment, malnutrition, solid organ transplantation, single lung transplantation, immunosuppression, and concomitant Aspergillus infection.

CONCLUSIONS

Mucormycosis infection in grafts after lung transplantation is a lethal complication poorly documented in the literature. Vigilance for Mucorales in these patients is crucial for early diagnosis.

Pneumonia in Transplant Recipients: A Comprehensive Review of Diagnosis and Management

Transplant recipients have an increased risk of complications, including graft dysfunction and infections, which can be life-threatening if not recognized early. Pneumonia ranks as one of the most frequent complications in both solid organ and hematopoietic stem cell transplants. Clinical symptoms manifest late during infections in immunocompromised patients. An aggressive approach centered on early confirmatory diagnosis and a low threshold for empiric therapy is often the most effective strategy. The isolation of a pathogen in an upper airway sample does not necessarily mean the same organism is responsible for pneumonia. Viruses such as CMV (cytomegalovirus virus) may function as co-pathogens for opportunistic infections in transplant recipients in addition to causing their own primary infectious syndrome. Furthermore, some viruses exhibit immunomodulatory effects that can affect the graft function. Given the exhaustive list of causative pathogens responsible for pneumonia, the best approach to the diagnosis is to have a conceptual framework that includes a detailed history, such as the type of transplant, degree of immunosuppression, antimicrobial prophylaxis, risk factors, time of presentation since transplantation and the radiographic pattern on the CT chest (computer tomography of the chest). Management depends predominantly on the degree of antimicrobial resistance, drug-to-drug interaction, and adjustments to the immunosuppression.

Changing Spectrum of Invasive Fungal Infections of the Anterior Skull Base

Objective  To study the etiological and anatomical factors in pathophysiology of invasive fungal rhinosinusitis affecting the skull base. Design  Retrospective clinical study over 5 years. Setting  Single-center tertiary referral hospital. Materials and Methods  All cases of invasive fungal rhinosinusitis with clinicoradiological and/or operative evidence of anterior and central skull base, orbit, and orbital apex involvement with or without intracranial disease were included in the study. Patients with a sinonasal-palatal disease without the involvement of the skull base or orbit were excluded from the study. In addition, we assessed the risk factors such as coronavirus disease 2019 (COVID-19) infection, diabetes mellitus (DM), and other immunocompromised conditions. Results  There were 79 patients, of which 65.8% had skull base rhino-oribitocerebral mucormycosis (ROCM), and 34.2% had Aspergillus infection. The mean duration from onset of the symptom to presentation of ROCM was 36.75 ± 20.97 days, while for the Aspergillus group was 21 weeks. The majority of patients (66%) with ROCM presented after 30 days of symptom onset. Among ROCM patients, 88.7% had a history of COVID-19 infection, and 96% had DM. In 40.8% of patients with Aspergillus infection, the tissue diagnosis was unavailable, and galactomannan assay and clinicoradiological assessment were used for diagnosis. The most common area of the skull base involved was the pterygopalatine fossa (88.5%), followed by the infratemporal fossa (73.1%). The most common neurovascular structure (75%) involved was the pterygopalatine ganglion and the infraorbital nerve. Conclusion  With the increasing incidence of invasive fungal infections worldwide, particularly after the COVID-19 pandemic, it is crucial to understand the evolving nature of this disease. ROCM, documented in the literature to cause fulminant disease, became a chronic illness, possibly due to the improvement of the patient's immunity during the disease course.

Clinical Characteristics and Prognoses of Mucormycosis in Four Children

Background

Mucormycosis is a fatal invasive fungal infection that commonly affects immunocompromised children. The aim of our study was to investigate the clinical manifestations, treatments, and prognosis of pediatric patients with mucormycosis.

Methods

We conducted a retrospective search in Shenzhen Children's Hospital from July 2013 to July 2023 for all patients with mucormycosis. The clinical manifestation, pathogen detection, radiology, treatments, and prognosis were analyzed.

Results

Four cases were identified. Underlying conditions included acute myeloid leukemia with myeloid sarcoma (n = 1), thalassemia (post-allogeneic hematopoietic stem cell transplantation; n = 1), systemic lupus erythematosus (n = 1), and bilateral nephroblastoma (post-bilateral nephrectomy; n = 1). Two patients were disseminated mucormycosis, one case was pulmonary mucormycosis, and one case was cerebral mucormycosis. Fever, cough, and dyspnea were the main clinical symptoms of pulmonary mucormycosis, headache was the main clinical symptom of cerebral mucormycosis. Lung CT findings included consolidation, multiple nodules, halo sign, air crescent sign, and pleural effusion. The contrast-enhanced CT showed pulmonary artery and pulmonary vein occlusions in two patients and pseudoaneurysm in two patients. Amphotericin B formulations were administered as first-line therapy in all cases; in three cases, Triazole was administered in combination with amphotericin B.

Conclusion

Mucormycosis is a life-threatening disease involving multiple systems. Aorta pseudoaneurysm is a rare and fatal complication, enhanced CT can assist in diagnosis. Early diagnosis and appropriate therapeutic strategies are needed.

Comprehensive Review on the Virulence Factors and Therapeutic Strategies with the Aid of Artificial Intelligence against Mucormycosis

Mucormycosis, a rare but deadly fungal infection, was an epidemic during the COVID-19 pandemic. The rise in cases (COVID-19-associated mucormycosis, CAM) is attributed to excessive steroid and antibiotic use, poor hospital hygiene, and crowded settings. Major contributing factors include diabetes and weakened immune systems. The main manifesting forms of CAM─cutaneous, pulmonary, and the deadliest, rhinocerebral─and disseminated infections elevated mortality rates to 85%. Recent focus lies on small-molecule inhibitors due to their advantages over standard treatments like surgery and liposomal amphotericin B (which carry several long-term adverse effects), offering potential central nervous system penetration, diverse targets, and simpler dosing owing to their small size, rendering the ability to traverse the blood-brain barrier via passive diffusion facilitated by the phospholipid membrane. Adaptation and versatility in mucormycosis are facilitated by a multitude of virulence factors, enabling the pathogen to dynamically respond to various environmental stressors. A comprehensive understanding of these virulence mechanisms is imperative for devising effective therapeutic interventions against this highly opportunistic pathogen that thrives in immunocompromised individuals through its angio-invasive nature. Hence, this Review delineates the principal virulence factors of mucormycosis, the mechanisms it employs to persist in challenging host environments, and the current progress in developing small-molecule inhibitors against them.

Unveiling the menace: a thorough review of potential pandemic fungal disease

Fungal diseases have emerged as a significant global health threat, with the potential to cause widespread outbreaks and significant morbidity and mortality. Anticipating future pandemic fungal diseases is essential for effective preparedness and response strategies. This comprehensive literature review aims to provide a comprehensive analysis of the existing research on this topic. Through an extensive examination of scholarly articles, this review identifies potential fungal pathogens that have the potential to become pandemics in the future. It explores the factors contributing to the emergence and spread of these fungal diseases, including climate change, globalization, and antimicrobial resistance. The review also discusses the challenges in diagnosing and treating these diseases, including limited access to diagnostic tools and antifungal therapies. Furthermore, it examines the strategies and interventions that can be employed to mitigate the impact of future pandemic fungal diseases, such as improved surveillance systems, public health education, and research advancements. The findings of this literature review contribute to our understanding of the potential risks posed by fungal diseases and provide valuable insights for public health professionals and policymakers in effectively preparing for and responding to future pandemic outbreaks. Overall, this review emphasizes the importance of proactive measures and collaborative efforts to anticipate and mitigate the impact of future pandemic fungal diseases.

Experimental Models to Study the Pathogenesis and Treatment of Mucormycosis

Mucormycosis presents a formidable challenge to clinicians and researchers. Animal models are an essential part of the effort to decipher the pathogenesis of mucormycosis and to develop novel pharmacotherapeutics against it. Diverse model systems have been established, using a range of animal hosts, immune and metabolic perturbations, and infection routes. An understanding of the characteristics, strengths, and drawbacks of these models is needed to optimize their use for specific research aims.

In vitro combination with doxycycline plus antifungals against clinical Mucorales pathogens

PURPOSE

Since systematic antifungals for mucormycosis showed variable MICs depending on strains, effective and safe antifungal therapy was still needed. This study is aimed to evaluate the in vitro activity of doxycycline combined with antifungal therapy against dominant Mucorales pathogens.

METHODS

Multidrug susceptibility testing was performed with doxycycline and antifungals, including itraconazole, posaconazole, and amphotericin, in 21 isolates of 8 dominant Mucorales pathogens.

RESULTS

The fractional inhibitory concentration index according to M38 showed one Rhizopus arrhizus isolate synergic (∑FICI = 0.375) and other isolates in addition (0.5 < ∑FICI < 4).

CONCLUSIONS

Doxycycline was found to have in vitro advantages in combined antifungal treatment over antifungals alone.

Transcription Factors Tec1 and Tec2 Play Key Roles in the Hyphal Growth and Virulence of Mucor lusitanicus Through Increased Mitochondrial Oxidative Metabolism

Mucormycosis is a lethal and difficult-to-treat fungal infection caused by fungi of the order Mucorales. Mucor lusitanicus, a member of Mucorales, is commonly used as a model to understand disease pathogenesis. However, transcriptional control of hyphal growth and virulence in Mucorales is poorly understood. This study aimed to investigate the role of Tec proteins, which belong to the TEA/ATTS transcription factor family, in the hyphal development and virulence of M. lusitanicus. Unlike in the genome of Ascomycetes and Basidiomycetes, which have a single Tec homologue, in the genome of Mucorales, two Tec homologues, Tec1 and Tec2, were found, except in that of Phycomyces blakesleeanus, with only one Tec homologue. tec1 and tec2 overexpression in M. lusitanicus increased mycelial growth, mitochondrial content and activity, expression of the rhizoferrin synthetase-encoding gene rfs, and virulence in nematodes and wax moth larvae but decreased cAMP levels and protein kinase A (PKA) activity. Furthermore, tec1- and tec2-overexpressing strains required adequate mitochondrial metabolism to promote the virulent phenotype. The heterotrimeric G beta subunit 1-encoding gene deletant strain (Δgpb1) increased cAMP-PKA activity, downregulation of both tec genes, decreased both virulence and hyphal development, but tec1 and tec2 overexpression restored these defects. Overexpression of allele-mutated variants of Tec1(S332A) and Tec2(S168A) in the putative phosphorylation sites for PKA increased both virulence and hyphal growth of Δgpb1. These findings suggest that Tec homologues promote mycelial development and virulence by enhancing mitochondrial metabolism and rhizoferrin accumulation, providing new information for the rational control of the virulent phenotype of M. lusitanicus.

Mucormycosis: update on clinical presentation, diagnosis, and treatment

PURPOSE OF REVIEW

Mucormycosis (MCR) is a common opportunistic mold infection, and Mucorales were recently designated by WHO as priority pathogens. The interest in this infection has risen significantly since the major outbreak of MCR in the context of the COVID-19 pandemic, particularly in India. Herein, we summarize recently (last 24 months) published information regarding clinical aspects of MCR.

RECENT FINDINGS

The disease remains protean in its clinical presentation, difficult to diagnose, and challenging to treat. In 2021, cases of COVID-19-associated mucormycosis (CAM) exploded in India during COVID-19 and manifested primarily as sino-orbital or sino-cerebral disease. Its classic risk factors included the triad of COVID-19, uncontrolled diabetes mellitus and use of corticosteroids. Despite difficulties in the timely diagnosis of MCR, significant progress has been made with the use of molecular techniques in blood to assist with earlier diagnosis, which can facilitate earlier appropriate therapy and improve outcomes. In addition, advances have been made in the use of imaging to stage the disease, determining what types of multimodal therapy are required depending on staging, and tissue-based identification of Mucorales.

SUMMARY

Although the outlook for MCR has improved, effective new antifungals, risk stratification, and the optimal multimodality approaches remain an unmet need.

Virulence traits and novel drug delivery strategies for mucormycosis post-COVID-19: a comprehensive review

The outbreak of a fatal black fungus infection after the resurgence of the cadaverous COVID-19 has exhorted scientists worldwide to develop a nutshell by repurposing or designing new formulations to address the crisis. Patients expressing COVID-19 are more susceptible to Mucormycosis (MCR) and thus fall easy prey to decease accounting for this global threat. Their mortality rates range around 32-70% depending on the organs affected and grow even higher despite the treatment. The many contemporary recommendations strongly advise using liposomal amphotericin B and surgery as first-line therapy whenever practicable. MCR is a dangerous infection that requires an antifungal drug administration on appropriate prescription, typically one of the following: Amphotericin B, Posaconazole, or Isavuconazole since the fungi that cause MCR are resistant to other medications like fluconazole, voriconazole, and echinocandins. Amphotericin B and Posaconazole are administered through veins (intravenously), and isavuconazole by mouth (orally). From last several years so many compounds are developed against invasive fungal disease but only few of them are able to induce effective treatment against the micorals. Adjuvant medicines, more particularly, are difficult to assess without prospective randomized controlled investigations, which are challenging to conduct given the lower incidence and higher mortality from Mucormycosis. The present analysis provides insight into pathogenesis, epidemiology, clinical manifestations, underlying fungal virulence, and growth mechanisms. In addition, current therapy for MCR in Post Covid-19 individuals includes conventional and novel nano-based advanced management systems for procuring against deadly fungal infection. The study urges involving nanomedicine to prevent fungal growth at the commencement of infection, delay the progression, and mitigate fatality risk.

Invasive splenic mucormycosis due to Rhizopus microsporus during chemotherapy for acute monocytic leukemia: a case report and literature review

Mucormycosis is a rare opportunistic fungal infection associated with high mortality that typically occurs in immunocompromised patients. It is difficult to diagnose owing to non-specific clinical manifestations, the serologic index, imaging features, and the limitations of diagnostic methods. The incidence of invasive splenic mucormycosis is extremely rare, with only a few cases documented in the literature. We report a survival case of invasive splenic mucormycosis involving the liver caused by Rhizopus microsporus in a patient during consolidation therapy for acute monocytic leukemia (AML-M5). The patient initially presented with recurrent fever and splenomegaly accompanied by multiple focal hypodensities unresponsive to empiric anti-infective treatment. Splenic mucormycosis was diagnosed by Contrast-Enhanced Ultrasonography (CEUS) and metagenomic next-generation sequencing (mNGS). However, surgical intervention carries a high risk due to the progressive involvement of the liver in invasive splenic mucormycosis. Fortunately, monotherapy with amphotericin B was effective, and the patient underwent allo-HSCT. This case aims to emphasize the importance of utilizing mNGS and CEUS for the timely diagnosis of mucormycosis to help clinicians identify splenic mucormycosis and initiate appropriate therapy as soon as possible to improve therapeutic efficacy and prognosis.

Epidemiology, Modern Diagnostics, and the Management of Mucorales Infections

Mucormycosis is an uncommon, yet deadly invasive fungal infection caused by the Mucorales moulds. These pathogens are a WHO-assigned high-priority pathogen group, as mucormycosis incidence is increasing, and there is unacceptably high mortality with current antifungal therapies. Current diagnostic methods have inadequate sensitivity and specificity and may have issues with accessibility or turnaround time. Patients with diabetes mellitus and immune compromise are predisposed to infection with these environmental fungi, but COVID-19 has established itself as a new risk factor. Mucorales also cause healthcare-associated outbreaks, and clusters associated with natural disasters have also been identified. Robust epidemiological surveillance into burden of disease, at-risk populations, and emerging pathogens is required. Emerging serological and molecular techniques may offer a faster route to diagnosis, while newly developed antifungal agents show promise in preliminary studies. Equitable access to these emerging diagnostic techniques and antifungal therapies will be key in identifying and treating mucormycosis, as delayed initiation of therapy is associated with higher mortality.

Two Rare Diseases, One Patient: A Case Report of Mucormycosis and Granulomatous Polyangiitis

Mucormycosis is a rare but fatal disease caused by a filamentous fungus involving the nose, paranasal sinuses, and brain. These organisms usually cause severe infections in immunocompromised individuals. Granulomatous polyangiitis (GPA), also known as Wegner's granulomatosis, is a rare, aseptic necrotizing granulomatous vasculitis involving small and medium-sized vessels commonly affecting the nose, ears, lungs, and kidneys. The simultaneous occurrence of mucormycosis and GPA, two rare diseases, in the same patient is exceedingly rare. In this case study, we describe a 40-year-old woman who presented with manifestations of both GPA and mucormycosis. She was started with steroids and antifungal agents and achieved significant improvement.

Serine/Threonine Phosphatase Calcineurin Orchestrates the Intrinsic Resistance to Micafungin in the Human-Pathogenic Fungus Mucor circinelloides

Procedures such as solid-organ transplants and cancer treatments can leave many patients in an immunocompromised state. This leads to their increased susceptibility to opportunistic diseases such as fungal infections. Mucormycosis infections are continually emerging and pose a serious threat to immunocompromised patients. Recently there has been a sharp increase in mucormycosis cases as a secondary infection in patients battling severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Mucorales fungi are notorious for presenting resistance to most antifungal drugs. The absence of effective means to treat these infections results in mortality rates approaching 100% in cases of disseminated infection. One of the most effective antifungal drug classes currently available is the echinocandins. Echinocandins seem to be efficacious in the treatment of many other fungal infections. Unfortunately, susceptibility testing has found that echinocandins have little to no effect on Mucorales fungi. In this study, we found that the model Mucorales Mucor circinelloides genome carries three copies of the genes encoding the echinocandin target protein β-(1,3)-d-glucan synthase (fksA, fksB, and fksC). Interestingly, we found that exposing M. circinelloides to micafungin significantly increased the expression of the fksA and fksB genes, resulting in an increased accumulation of β-(1,3)-d-glucan on the cell walls. However, this overexpression of the fks genes is not directly connected to the intrinsic resistance. Subsequent investigation discovered that the serine/threonine phosphatase calcineurin regulates the expression of fksA and fksB, and the deletion of calcineurin results in a decrease in expression of all three fks genes. Deletion of calcineurin also results in a lower minimum effective concentration (MEC) of micafungin. In addition, we found that duplication of the fks gene is also responsible for the intrinsic resistance, in which lack of either fksA or fksB led a lower MEC of micafungin. Together, these findings demonstrate that calcineurin and fks gene duplication contribute to the intrinsic resistance to micafungin we observe in M. circinelloides.

Acute myocardial infarction caused by coronary mucormycotic embolism

Described here is a rare cardiac complication attributed to mucormycosis in a 63-year-old woman who developed sudden cardiac arrest and pulmonary insufficiency in the course of being treated for acute monocytic leukemia (acute myelogenous leukemia, AML M5a). At autopsy, fresh thrombi were noted in the left pulmonary artery and the left atrium. Postmortem coronary angiography revealed complete occlusion of the circumflex branch of the left coronary artery, and histological examination showed a mucormycotic embolism in the corresponding portion. Multiple small mucormycotic thrombi were also noted in both coronary and pulmonary arteries with hemorrhagic infarction in the corresponding areas.

Diagnostic and Treatment Challenges of Emergent COVID-Associated-Mucormycosis: A Case Report and Review of the Literature

Mucormycosis is a rare fungal infection, with high mortality, commonly associated with diabetes, malignancies, immunosuppressive therapy, and other immunodeficiency conditions. The emergence of mucormycosis cases has been advanced by the COVID-19 pandemic. Clinical presentation is variable, from asymptomatic to persistent fever or localized infections. We present a case of a Romanian old man, without diabetes or other immunodepression, with COVID-19 who developed severe rhino-orbital mucormycosis and bacterial superinfections, with Pseudomonas aeruginosa and Klebsiella pneumoniae. The late diagnostic and antifungal treatment was related to extensive lesions, bone and tissue loss, and required complex reconstruction procedures. We review the relationships between mucormycosis, COVID-19, and bacterial associated infections. The suspicion index of mucormycosis should be increased in medical practice. The diagnostic and treatment of COVID-19-Associated-Mucormycosis is currently challenging, calling for multidisciplinary collaboration.