Mucormycosis in patients with haematological malignancies: a retrospective clinical study of 37 cases. GIMEMA Infection Program (Gruppo Italiano Malattie Ematologiche Maligne dell'Adulto)

Molecular mechanisms that govern infection and antifungal resistance in Mucorales

SUMMARYThe World Health Organization has established a fungal priority pathogens list that includes species critical or highly important to human health. Among them is the order Mucorales, a fungal group comprising at least 39 species responsible for the life-threatening infection known as mucormycosis. Despite the continuous rise in cases and the poor prognosis due to innate resistance to most antifungal drugs used in the clinic, Mucorales has received limited attention, partly because of the difficulties in performing genetic manipulations. The COVID-19 pandemic has further escalated cases, with some patients experiencing the COVID-19-associated mucormycosis, highlighting the urgent need to increase knowledge about these fungi. This review addresses significant challenges in treating the disease, including delayed and poor diagnosis, the lack of accurate global incidence estimation, and the limited treatment options. Furthermore, it focuses on the most recent discoveries regarding the mechanisms and genes involved in the development of the disease, antifungal resistance, and the host defense response. Substantial advancements have been made in identifying key fungal genes responsible for invasion and tissue damage, host receptors exploited by the fungus to invade tissues, and mechanisms of antifungal resistance. This knowledge is expected to pave the way for the development of new antifungals to combat mucormycosis. In addition, we anticipate significant progress in characterizing Mucorales biology, particularly the mechanisms involved in pathogenesis and antifungal resistance, with the possibilities offered by CRISPR-Cas9 technology for genetic manipulation of the previously intractable Mucorales species.

Part 2: Mucormycosis: Focus on Therapy

INTRODUCTION

Mucormycosis (MCR) a rare but life-threatening infection occurs primarily in immunocompromised hosts. Mortality rates with invasive MCR are high (>30-50%), up to 90% with disseminated disease, but lower (10-30%) with localized cutaneous disease. Due to the rarity of MCR, randomized, controlled therapeutic trials are lacking. Lipid formulations of amphotericin B (LFAB) are the mainstay of therapy but oral triazoles (posaconazole and isavuconazole) may be effective as step-down therapy or in MCR cases refractory to or intolerant of LFAB. Early surgical debridement or excision play important adjunctive roles in localized invasive disease. Control of hyperglycemia in diabetic patients, correction of neutropenia and reduction of immunosuppressive therapy is critical for optimal survival.

AREAS COVERED

The authors discuss various therapeutic options for mucormycosis. A literature search of mucormycosis therapies was performed via PubMed (up to December 2022), using the key words: invasive fungal infections; mold; mucormycosis; Mucorales; amphotericin B; isavuconazole; posaconazole.

EXPERT OPINION

Randomized, controlled therapeutic trials are lacking. Lipid formulations of amphotericin B (LFAB) are the mainstay of therapy but oral triazoles (posaconazole and isavuconazole) may be effective as step-down therapy, in MCR cases refractory to or intolerant of LFAB. We encourage early surgical debridement or excision as adjunctive measures.

Part 1: Mucormycosis: Prevalence, Risk Factors, Clinical Features and Diagnosis

INTRODUCTION

Mucormycosis (MCR) is caused by filamentous molds within the Class Zygomycetes and Order Mucorales. Infections can result from inhalation of spores into the nares, oropharynx or lungs, ingestion of contaminated food or water, or inoculation into disrupted skin or wounds. In developed countries, MCR occurs primarily in severely immunocompromised hosts. In contrast, in developing/low income countries, most cases of MCR occur in persons with poorly controlled diabetes mellitus and some cases in immunocompetent subjects following trauma. Mucormycosis exhibits a propensity to invade blood vessels, leading to thrombosis and infarction of tissue. Mortality rates associated with invasive MCR are high and can exceed 90% with disseminated disease. Mucormycosis can be classified as one of six forms: (1) rhino-orbital-cerebral mucormycosis (ROCM); (2) pulmonary; (3) cutaneous; (4) gastrointestinal or renal (5); disseminated; (6) uncommon (focal) sites.

AREAS COVERED

The authors discuss the prevalence, risk factors and clinical features of mucormycosis.A literature search of mucormycosis was performed via PubMed (up to November 2022), using the key words: invasive fungal infections; mold; mucormycosis; Mucorales; Zyzomyces; Zygomycosis; Rhizopus, diagnosis.

EXPERT OPINION

Mucormycosis occurs primarily in severely immunocompromised hosts. Mucormycosis can progress rapidly, and delay in initiating treatment by even a few days worsens outcomes.

Clinical Features and Treatment Progress of Invasive Mucormycosis in Patients with Hematological Malignancies

The incidence rate of invasive mucormycosis (IM) in patients with hematological malignancies (HMs) is increasing year by year, ranging from 0.07% to 4.29%, and the mortality rate is mostly higher than 50%. With the ongoing pandemic of COVID-19, COVID-19-associated mucormycosis (CAM) also became a global health threat. Patients with high risk factors such as active HMs, relapsed/refractory leukemia, prolonged neutropenia may still develop breakthrough mucormycosis (BT-MCR) even under the prophylaxis of Mucorales-active antifungals, and such patients often have higher mortality. Rhizopus spp. is the most common genus associated with IM, followed by Mucor spp. and Lichtheimia spp. Pulmonary mucormycosis (PM) is the most common form of IM in patients with HMs, followed by rhino-orbital-cerebral mucormycosis (ROCM) and disseminated mucormycosis. The prognosis of IM patients with neutrophil recovery, localized IM and receiving early combined medical-surgical therapy is usually better. As for management of the disease, risk factors should be eliminated firstly. Liposome amphotericin B (L-AmB) combined with surgery is the initial treatment scheme of IM. Those who are intolerant to L-AmB can choose intravenous formulations or tablets of isavuconazole or posaconazole. Patients who are refractory to monotherapy can turn to combined antifungals therapy.

What Is New in Pulmonary Mucormycosis?

Mucormycosis is a rare but life-threatening fungal infection due to molds of the order Mucorales. The incidence has been increasing over recent decades. Worldwide, pulmonary mucormycosis (PM) presents in the lungs, which are the third main location for the infection after the rhino-orbito-cerebral (ROC) areas and the skin. The main risk factors for PM include hematological malignancies and solid organ transplantation, whereas ROC infections are classically favored by diabetes mellitus. The differences between the ROC and pulmonary locations are possibly explained by the activation of different mammalian receptors—GRP78 in nasal epithelial cells and integrin β1 in alveolar epithelial cells—in response to Mucorales. Alveolar macrophages and neutrophils play a key role in the host defense against Mucorales. The diagnosis of PM relies on CT scans, cultures, PCR tests, and histology. The reversed halo sign is an early, but very suggestive, sign of PM in neutropenic patients. Recently, the serum PCR test showed a very encouraging performance for the diagnosis and follow-up of mucormycosis. Liposomal amphotericin B is the drug of choice for first-line therapy, together with correction of underlying disease and surgery when feasible. After a stable or partial response, the step-down treatment includes oral isavuconazole or posaconazole delayed release tablets until a complete response is achieved. Secondary prophylaxis should be discussed when there is any risk of relapse, such as the persistence of neutropenia or the prolonged use of high-dose immunosuppressive therapy. Despite these novelties, the mortality rate from PM remains higher than 50%. Therefore, future research must define the place for combination therapy and adjunctive treatments, while the development of new treatments is necessary.

Differential diagnosis of a local form of granulomatosis with polyangiitis: nasal cavity and paranasal sinuses lesions (part 1)

Granulomatosis with polyangiitis (GPA) is a primary vasculitis associated with antineutrophil cytoplasmic antibodies, characterized by necrotizing vasculitis with predominant involvement of small vessels of various localizations and necrotizing granulomatous inflammation with multiple clinical manifestations. GPA remains one of the most severe systemic vasculitis with unfavorable prognosis. When analyzing the course of the disease, there are two variants of GPA, local (with lesions of the upper respiratory tract, URT, organs of vision and hearing) and generalized (with lesions of the URT, organs of vision and hearing in combination with the lungs and/or kidneys, gastrointestinal tract, nervous systems, skin involvement).The article discusses the differential diagnosis of the disease with the nasal cavity and paranasal sinuses lesions onset, which requires an interdisciplinary approach and interaction of doctors of different specialties.

Iranian patients co-infected with COVID-19 and mucormycosis: the most common predisposing factor, clinical outcomes, laboratory markers and diagnosis, and drug therapies

BACKGROUND

The newly emerged pandemic of coronavirus disease-2019 (COVID-19) is the world's main health challenge because infected patients become vulnerable to a variety of opportunistic diseases.

OBJECTIVE

This study aimed to assess clinical outcomes, diagnosis, utilized drug therapies, and ongoing COVID-19 practices in Iranian cases co-infected with COVID-19 and mucormycosis.

PARTICIPANTS AND METHODS

A case-series analysis was conducted in the presence of 10 patients with COVID-19 and mucormycosis co-infection (two men and eight women; mean age of 48.8 years) from March to October 2020. Demographic variables, signs/symptoms, and comorbidities of all patients were recorded. COVID-19 was confirmed with reverse transcription polymerase chain reaction (RT-PCR) nasopharyngeal swab tests and high-resolution computed tomography (HR-CT)_ scans.

RESULTS

All patients had a positive RT-PCR for SARS-CoV-2. Eight patients had a history of diabetes, while three of them exhibited a hypertension history. Remarkable laboratory findings were elevated fasting blood sugar in 6 cases and anaemia in four patients. A rhino-orbital-cerebral of mucormycosis in all patients was detected based on HR-CT scans and otorhinolaryngological or ophthalmological examinations. Neurological disorders including facial, trigeminal, optic, and oculomotor nerve involvement resulted in paraesthesia, pain, ptosis, no light perception, blurred vision, and papilledema in five cases. Maxillary and ethmoid sinuses were the most common sites of involvement.

CONCLUSION

Vulnerable COVID-19 patients with comorbidities, any facial involvements, or treated by excessive doses of glucocorticoids and antibiotics should undergo precise examinations during the appearance of early signs and hospitalization to diagnose and treat mucormycosis using the standard care and antifungal treatments.

Characterizing patients with rare mucormycosis infections using real-world data

BACKGROUND

Invasive mucormycosis (IM) is a rare and often life-threatening fungal infection, for which clinical and epidemiological understanding is lacking. Electronic health record (EHR) data can be utilized to elucidate large populations of patients with IM to address this unmet need. This study aimed to descriptively assess data on patients with IM using the Optum® EHR dataset.

METHODS

US patient data from the Optum® deidentified EHR dataset (2007-2019) were analyzed to identify patients with IM. Patients with hematologic malignancies (HM), at high risk of IM, were selected and sorted by IM diagnosis (ICD9 117.7; ICD10 B46). Demographics, comorbidities/other diagnoses, and treatments were analyzed in patients with IM.

RESULTS

In total, 1133 patients with HM and IM were identified. Most were between 40 and 64 years of age, Caucasian, and from the Midwest. Essential primary hypertension (50.31%) was the most common comorbidity. Of the 1133 patients, only 33.72% were prescribed an antifungal treatment. The most common antifungal treatments were fluconazole (24.27%) and posaconazole (16.33%), which may have been prophylactic, and any AmB (15.62%).

CONCLUSIONS

A large population of patients with IM were identified, highlighting the potential of analyzing EHR data to investigate epidemiology, diagnosis, and the treatment of apparently rare diseases.

Case Report: Metagenomics Next-Generation Sequencing for Diagnosing Cerebral Infarction and Infection Caused by Hematogenous Disseminated Mucormycosis in a Patient With Acute Lymphoblastic Leukemia

Disseminated mucormycosis, a serious complication, is associated with high mortality in patients with acute leukemia after chemotherapy. Blood cultures are always negative because of recurrent empirical antifungal treatments. The identification of pathogens is important for diagnosis and therapy. In this case report, we diagnosed culture-negative disseminated mucormycosis with Rhizomucor miehei infection leading to cerebral infarction in a patient with leukemia using metagenomics next-generation sequencing (mNGS) form peripheral blood, cerebral spinal fluid, and bronchoalveolar lavage fluid. mNGS technology can be applied to precisely diagnose culture-negative disseminated mucormycosis.

Consensus guidelines for the diagnosis and management of invasive fungal disease due to moulds other than Aspergillus in the haematology/oncology setting, 2021

Invasive fungal disease (IFD) due to moulds other than Aspergillus is a significant cause of mortality in patients with malignancies or post haemopoietic stem cell transplantation. The current guidelines focus on the diagnosis and management of the common non-Aspergillus moulds (NAM), such as Mucorales, Scedosporium species (spp.), Lomentospora prolificans and Fusarium spp. Rare but emerging NAM including Paecilomyces variotii, Purpureocillium lilacinum and Scopulariopsis spp. are also reviewed. Culture and histological examination of tissue biopsy specimens remain the mainstay of diagnosis, but molecular methods are increasingly being used. As NAM frequently disseminate, blood cultures and skin examination with biopsy of any suspicious lesions are critically important. Treatment requires a multidisciplinary approach with surgical debridement as a central component. Other management strategies include control of the underlying disease/predisposing factors, augmentation of the host response and the reduction of immunosuppression. Carefully selected antifungal therapy, guided by susceptibility testing, is critical to cure. We also outline novel antifungal agents still in clinical trial which offer substantial potential for improved outcomes in the future. Paediatric recommendations follow those of adults. Ongoing epidemiological research, improvement in diagnostics and the development of new antifungal agents will continue to improve the poor outcomes that have been traditionally associated with IFD due to NAM.

Rhino-orbito-cerebral mucormycosis during the COVID-19 third wave in 2021: an Egyptian preliminary report from a single tertiary hospital

COVID-19 is a pandemic disease which predominantly affects the respiratory system with high critical care mortality and morbidity; however, it also causes multi-organ dysfunction in a subset of patients. Although causality between COVID-19 and mucormycosis remains unclear, many factors including glucocorticoids, worsening of blood glucose control, and viral-induced lymphopenia have been attributed to cause mucormycosis in patients with COVID-19. In COVID-19 patients, especially those who need oxygen support, inflammatory and cytokine storm or usage of steroids make the immune system weak. This may pave the way for opportunistic infections including mucormycosis. We report fourteen cases of COVID-19 infection, who developed rhino-orbito-cerebral mucormycosis, during treatment. Early recognition of this life-threatening infection is the key to allow for optimal treatment and improved outcomes.

Identifying Mucormycosis Severity in Indian COVID-19 Patients: A Nano-Based Diagnosis and the Necessity for Critical Therapeutic Intervention

The COVID-19 infection caused by the new SARS-CoV-2 virus has been linked to a broad spectrum of symptoms, from a mild cough to life-threatening pneumonia. As we learn more about this unusual COVID-19 epidemic, new issues are emerging and being reported daily. Mucormycosis, also known as zygomycosis or phycomycosis, causes severe fungal illness to individuals with a weakened immune system. It is a devastating fungal infection, and the most frequent kind is the rhino cerebral type. As a devastating second wave of COVID-19 sweeps India, doctors report several instances involving a strange illness-sometimes known as the "black fungus"-among returning and recovered COVID-19 patients. This paper analyzes the existing statistical data to address the severity of prevalence and further notes the nano-based diagnostic parameters, clinical presentations, its connection with other conditions like diabetes, hypertension, and GI disorders, and the importance of anti-fungal therapy in treating the same. Anti-fungal therapies, as well as surgical interventions, are currently used for the treatment of the disease. Proper and timely diagnosis is necessary, along with the reduction in the spread of COVID-19. From the review, it was found that timely pharmacologic interventions and early diagnosis by using a nano-based diagnostic kit can help control the disease. Additionally, this paper provides novel information about the nanotechnology approaches such as fungal detection biosensors, nucleic acids-based testing, point-of-care tests, and galactomannans detection, in the diagnosis of mucormycosis, and thereby reinforces the need for further research on the topic.

Mucormycosis: An opportunistic pathogen during COVID-19

The pandemic of coronavirus disease 2019 (COVID-19) still remains on an upsurge trend. The second wave of this disease has led to panic in many countries, including India and some parts of the world suffering from the third wave. As there are no proper treatment options or remedies available for this deadly infection, supportive care equipment's such as oxygen cylinders, ventilators and heavy use of steroids play a vital role in the management of COVID-19. In the midst of this pandemic, the COVID-19 patients are acquiring secondary infections such as mucormycosis also known as black fungus disease. Mucormycosis is a serious, but rare opportunistic fungal infection that spreads rapidly, and hence prompt diagnosis and treatment are necessary to avoid high rate of mortality and morbidity rates. Mucormycosis is caused by the inhalation of its filamentous (hyphal form) fungi especially in the patients who are immunosuppressed. Recent studies have documented alarming number of COVID-19 patients with mucormycosis infection. Most of these patients had diabetes and were administered steroids for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection and were consequently more prone to mucormycosis. Hence, the present review emphasizes mucormycosis and its related conditions, its mechanism in normal and COVID-19 affected individuals, influencing factors and challenges to overcome this black mold infection. Early identification and further investigation of this fungus will significantly reduce the severity of the disease and mortality rate in COVID-19 affected patients.

Risk Factors for Mucormycosis in COVID-19 Patients

: Opportunistic infections, such as mucormycosis, in coronavirus disease 2019 (COVID-19) patients has become a new health challenge. Since opportunistic infections can exacerbate COVID-19 patients' status, it is vital to identify the risk factors to prevent, diagnose, and treat them as soon as possible. Viral, fungal, environmental, and host factors may be responsible for this situation. Long hospital stays, impaired host immune system function due to viral infection, and excessive consumption of glucocorticoids in managing COVID-19 patients are the main risk factors for the increased risk of mucormycosis in COVID-19 patients. Educating health care workers and considering the association between mucormycosis of the paranasal sinuses and different strains of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as the cause of COVID-19 can help prevent invasive fungal sinusitis in COVID-19 patients.

Cerebral mucormycosis: neuroimaging findings and histopathological correlation

INTRODUCTION

Mucormycosis are infections caused by molds of the order Mucorales. These opportunistic infections are rare, difficult to diagnose, and have a poor prognosis. We aimed to describe common radiographic patterns that may help to diagnose cerebral mucormycosis and search for histopathological correlations with imaging data.

METHODS

We studied the radiological findings (CT and MRI) of 18 patients with cerebral mucormycosis and four patients' histopathological findings.

RESULTS

All patients were immunocompromised and/or diabetic. The type of lesions depended on the infection's dissemination pathway. Hematogenous dissemination lesions were most frequently abscesses (59 lesions), cortical, cortical-subcortical, or in the basal ganglia, with a halo aspect on DWI for lesions larger than 1.6 cm. Only seven lesions were enhanced after contrast injection, with different presentations depending on patients' immune status. Ischemia and hemorrhagic areas were also seen. Vascular lesions were represented by stenosis and thrombosis. Direct posterior extension lesions were bi-fronto basal hypodensities on CT and restricted diffusion without enhancement on MRI. A particular extension, perineural spread, was seen along the trigeminal nerve. Histopathological analysis found endovascular lesions with destruction of vessel walls by Mucorales, microbleeds around vessels, as well as acute and chronic inflammation.

CONCLUSIONS

MRI is the critical exam for cerebral mucormycosis. Weak ring enhancement and reduced halo diffusion suggest the diagnosis of fungal infections. Involvement of the frontal lobes should raise suspicion of mucormycosis (along with aspergillosis). The perineural spread can be considered a more specific extension pathway of mucormycosis.

Has the mortality from pulmonary mucormycosis changed over time? A systematic review and meta-analysis

OBJECTIVES

Pulmonary mucormycosis (PM) is increasingly being reported in immunocompromised patients and has a high mortality. Our aim was to assess the mortality of PM and its trend over time. We also evaluated the role of combined medical-surgical therapy in PM.

METHODS

We performed a systematic review of Pubmed, Embase, and Cochrane central databases. Studies were eligible if they described at least five confirmed cases of PM and reported mortality. We also assessed the effect of combined medical-surgical therapy versus medical treatment alone on PM mortality. We used a random-effects model to estimate the pooled mortality of PM and compared it across three time periods. The factors influencing mortality were assessed using meta-regression. We evaluated the risk difference (RD) of death in the following: subjects undergoing combined medical-surgical therapy versus medical therapy alone, subjects with isolated PM versus disseminated disease, and PM in diabetes mellitus (DM) versus non-DM as a risk factor.

RESULTS

We included 79 studies (1544 subjects). The pooled mortality of PM was 57.1% (95% confidence interval [CI] 51.7-62.6%). Mortality improved significantly over time (72.1% versus 58.3% versus 49.8% for studies before 2000, 2000-2009, and 2010-2020, respectively, p 0.00001). This improved survival was confirmed in meta-regression after adjusting for the study design, the country's income level, and the sample size. Combined medical-surgical therapy was associated with a significantly lower RD (95%CI) of death: -0.32 (-0.49 to -0.16). The disseminated disease had a higher risk of death than isolated PM, but DM was not associated with a higher risk of death than other risk factors.

CONCLUSIONS

While PM is still associated with high mortality, we noted improved survival over time. Combined medical-surgical therapy improved survival compared to medical treatment alone.

A rare case of colon obstruction due to gastrointestinal basidiobolomycosis in a 36-year-old woman

INTRODUCTION

Gastrointestinal basidiobolomycosis (GIB) is an uncommon fungal infection caused byBasidiobolus ranarum, with less than 80 cases reported in the literature.

PRESENTATION OF CASE

A 36-year-old woman presented with colicky upper abdominal pain for 2 months and inability to pass stool for 2 days. Computed tomography of the abdomen and colonoscopy both showed a mass in the transverse colon. Colonoscopic biopsy suggested a zygomycosis. Laparotomy revealed a perforated mass in the transverse colon; the mass also involved the small bowel and stomach. En bloc resection was performed, and the incision was closed for a second-look procedure. The patient was admitted to the intensive care unit and placed on a ventilator and inotropes; however, her condition deteriorated, and she died on day 24 post admission. The histopathology report (obtained after the patient's death) was consistent with GIB.

DISCUSSION

Gastrointestinal basidiobolomycosis presents with nonspecific signs and symptoms and so the diagnosis is easily missed or delayed. Timely, accurate diagnosis is crucially important, especially when there is intestinal obstruction and sepsis. Persistent severe abdominal pain in a patient with neutropenia should alert the physician to the possibility of a fungal infection. There are reports from several countries of basidiobolomycosis in immunocompetent hosts. The disease shows no age predilection, but males may be more susceptible. Treatment is with surgical debridement and antifungal drugs-ideally the lipid formulation of amphotericin B.

CONCLUSION

Gastrointestinal basidiobolomycosis is a rare infection that can be fatal if not diagnosed and treated early.

Developments in identifying and managing mucormycosis in hematologic cancer patients

INTRODUCTION

Mucormycoses represent a rare but very aggressive class of mold infections occurring in patients with hematological malignancies (HMs). In the past, patients at high risk of invasive mucomycosis (IM) were those affected by acute myeloid leukemia but over the last ten years the prophylaxis with a very effective mold-active drug, such as posaconazole, has completely modified the epidemiology. In fact, IM is now observed more frequently in patients with lymphoproliferative disorders who do not receive antifungal prophylaxis.

AREAS COVERED

The attention was focused on the epidemiology, diagnosis, prophylaxis and treatment of IM in HMs. Authors excluded pediatric patients considering the different epidemiology and differences in treatment given the limitation of the use of azoles in the pediatric field. A systematic literature review was performed using PubMed database listings between February 2014 and February 2020 using the following MeSH terms: leukemia, hematological malignancies, stem cell transplantation, mucormycosis, molds, prophilaxis, treatment.

EXPERT OPINION

The epidemiology of mucormycosis in HMs is changing in the last years. The availability of drugs more effective than in the past against this infection has reduced the mortality; however, a timely diagnosis remains a relevant problem potentially influencing the outcome of hematologic patients with IM.

Mucorales Species and Macrophages

Mucormycosis is an emerging fungal infection caused by Mucorales with an unacceptable high mortality rate. Mucorales is a complex fungal group, including eleven different genera that can infect humans. This heterogeneity is associated with species-specific invasion pathways and responses to the host defense mechanisms. The host innate immune system plays a major role in preventing Mucorales growth and host invasion. In this system, macrophages are the main immune effector cells in controlling these fungi by rapid and efficient phagocytosis of the spores. However, Mucorales have evolved mechanisms to block phagosomal maturation and species-specific mechanisms to either survive as dormant spores inside the macrophage, as Rhizopus species, or geminate and escape, as Mucor species. Classical fungal models of mucormycosis, mostly Rhizopus, have made important contributions to elucidate key aspects of the interaction between Mucorales and macrophages, but they lack robust tools for genetic manipulation. The recent introduction of the genetically tractable Mucor circinelloides as a model of mucormycosis offers the possibility to analyze gene function. This has allowed the identification of regulatory pathways that control the fungal response to phagocytosis, including a non-canonical RNAi pathway (NCRIP) that regulates the expression of most genes regulated by phagocytosis.

Global guideline for the diagnosis and management of mucormycosis: an initiative of the European Confederation of Medical Mycology in cooperation with the Mycoses Study Group Education and Research Consortium

Mucormycosis is a difficult to diagnose rare disease with high morbidity and mortality. Diagnosis is often delayed, and disease tends to progress rapidly. Urgent surgical and medical intervention is lifesaving. Guidance on the complex multidisciplinary management has potential to improve prognosis, but approaches differ between health-care settings. From January, 2018, authors from 33 countries in all United Nations regions analysed the published evidence on mucormycosis management and provided consensus recommendations addressing differences between the regions of the world as part of the "One World One Guideline" initiative of the European Confederation of Medical Mycology (ECMM). Diagnostic management does not differ greatly between world regions. Upon suspicion of mucormycosis appropriate imaging is strongly recommended to document extent of disease and is followed by strongly recommended surgical intervention. First-line treatment with high-dose liposomal amphotericin B is strongly recommended, while intravenous isavuconazole and intravenous or delayed release tablet posaconazole are recommended with moderate strength. Both triazoles are strongly recommended salvage treatments. Amphotericin B deoxycholate is recommended against, because of substantial toxicity, but may be the only option in resource limited settings. Management of mucormycosis depends on recognising disease patterns and on early diagnosis. Limited availability of contemporary treatments burdens patients in low and middle income settings. Areas of uncertainty were identified and future research directions specified.

Disseminated Mucormycosis with Extensive Cardiac Involvement

Mucormycosis is an opportunistic fungal infection. Cardiac involvement is a rare, yet fatal, complication that can occur in disseminated disease. A strong index of suspicion is necessary for prompt treatment, especially in high-risk patients. We present a 62-year-old male patient with a history of diabetes and acute myeloid leukemia; he had pulmonary mucormycosis that was complicated by cardiac involvement as part of disseminated mucormycosis syndrome.

Successful treatment of pulmonary mucormycosis in two pediatric hematopoietic stem cell transplant patients

Pulmonary mucormycosis diagnosed immediately after hematopoietic stem cell transplantation frequently portends a poor prognosis. However, here we describe two cases in children that were treated successfully to highlight the efficacy of a multidisciplinary approach. Despite diagnosis in the immediate post-transplant period and requirement for ongoing immunosuppression to prevent or treat GVHD, both are long-term survivors due to early surgical debridement with transfusion support and prompt initiation of targeted antifungal therapy. In the absence of evidence-based treatment guidelines, survival of pulmonary mucormycosis is achievable even in high-risk patients with a multidisciplinary team to guide management.

Combined Medical and Surgical Management of Hepatic Mucormycosis in an Adult with Acute Myeloid Leukemia: Case Report and Review of the Literature

Hepatic mucormycosis is a disease caused by a ubiquitous fungus which is especially important in patients with hematologic malignancies. We present a case of an adult patient with acute myeloid leukemia who developed the infection after undergoing chemotherapy. His successful management was an integrated approach of a minimally invasive surgical resection with anti-fungal therapy. We describe the management of this patient and a review of the literature.

A Comprehensive Review of Skull Base Osteomyelitis: Diagnostic and Therapeutic Challenges among Various Presentations

Skull base osteomyelitis (SBO) is a complex and fatal clinical entity that is often misdiagnosed for malignancy. SBO is commonly a direct complication of otogenic, sinogenic, odontogenic, and rhinogenic infections and can present as central, atypical, or pediatric clival SBO. This review describes the clinical profile, investigational approach, and management techniques for these variants. A comprehensive literature review was performed in PubMed, MEDLINE, Research Gate, EMBASE, Wiley Online Library, and various Neurosurgical and Neurology journals with the keywords including: SBO, central or atypical SBO, fungal osteomyelitis, malignant otitis externa, temporal bone osteomyelitis, and clival osteomyelitis. Each manuscript's reference list was reviewed for potentially relevant articles. The search yielded a total of 153 articles. It was found that with early and aggressive culture guided long-term intravenous broad-spectrum antibiotic therapy decreases post-infection complications. In cases of widespread soft tissue involvement, an early aggressive surgical removal of infectious sequestra with preferentially Hyperbaric Oxygen (HBO) therapy is associated with better prognosis of disease, less neurologic sequelae and mortality rate. Complete resolution of the SBO cases may take several months. Since early treatment can improve mortality rates, it is paramount that the reporting radiologists and treating clinicians are aware of the cardinal diagnostic signs to improve clinical outcomes of the disease. It will decrease delayed diagnosis and under treatment of the condition. However, due to rarity of the condition, complete prognostic factors have not fully been analyzed and discussed in the literature.

Innate and Adaptive Immunity to Mucorales

Mucormycosis is an invasive fungal infection characterised by rapid filamentous growth, which leads to angioinvasion, thrombosis, and tissue necrosis. The high mortality rates (50-100%) associated with mucormycosis are reflective of not only the aggressive nature of the infection and the poor therapeutics currently employed, but also the failure of the human immune system to successfully clear the infection. Immune effector interaction with Mucorales is influenced by the developmental stage of the mucormycete spore. In a healthy immune environment, resting spores are resistant to phagocytic killing. Contrarily, swollen spores and hyphae are susceptible to damage and degradation by macrophages and neutrophils. Under the effects of immune suppression, the recruitment and efficacy of macrophage and neutrophil activity against mucormycetes is considerably reduced. Following penetration of the endothelial lining, Mucorales encounter platelets. Platelets adhere to both mucormycete spores and hyphae, and exhibit germination suppression and hyphal damage capacity in vitro. Dendritic cells are activated in response to Mucorales hyphae only, and induce adaptive immunity. It is crucial to further knowledge regarding our immune system's failure to eradicate resting spores under intact immunity and inhibit fungal growth under immunocompromised conditions, in order to understand mucormycosis pathogenicity and enhance therapeutic strategies for mucormycosis.

Evaluation of 30 cases of mucormycosis at a university hospital in Iran

Mucormycosis is a deadly invasive fungal infection and mainly affects immunocompromised patients. To investigate the clinical features of patients who developed mucormycosis and to determine the parameters, which influenced the outcome following mycotic infection. The current investigation retrospectively evaluated the demographic characteristics, clinical features, therapeutic data, as well as the outcomes of treatment in all cases of proven and probable mucormycosis diagnosed from 2002 until 2016 in our hospital. A total of thirty cases were recorded. Rhizopus spp. was the predominant pathogen among the identified Mucorales (26.7%). Diabetes mellitus (46.7%) and haematological malignancy (40%), were the most common underlying diseases. With regard to predisposing factors, neutropenia (43.3%) and chemotherapy (40%) were the leading concomitant parameters. The most frequent sites of infection were lung (30%) and sinus (26.7%), whereas disseminated infection was also found in nine of 30 patients (30%). Neutropenia remained the only independent factor associated with mortality (Relative Risk=3.557, 95% CI=1.365-9.271, P=.009). Diagnostic delay -either due to delayed presentation of patients to our centre or insufficient awareness about invasive fungal infection among our clinicians- is a likely explanation for such a high mortality rate in our series.

Pulmonary mucormycosis: clinical features and outcomes

PURPOSE

Mucormycosis encompasses a group of opportunistic fungal infections caused by Zygomycetes, order Mucorales. Mucormycosis can manifest as rhino-orbito-cerebral, pulmonary, gastrointestinal, cutaneous, and disseminated infections. Pulmonary mucormycosis is the second most common presentation. This manuscript characterizes the demographics, clinical presentation, diagnostic procedures, radiologic findings, therapeutic interventions, and outcome in pulmonary mucormycosis.

METHODS

We retrospectively reviewed clinical data of 35 patients with pulmonary mucormycosis from 2000 to 2015. Microbiologic diagnosis was based on positive culture from a sterile site or findings on histopathology consistent with mucormycosis. Independent predictors of 28-day mortality were assessed using logistic regression. Survival curves were estimated using Kaplan-Meier method.

RESULTS

There was male predominance with a mean age of 55 ± 15 years. Analysis of predisposing conditions revealed the prevailing presence of malignancy. Sixty-six percent of patients were receiving immunosuppressive agents. Common presenting clinical findings were fever, neutropenia, dyspnea, and cough. Radiologic findings included pleural effusion and nodules. All patients received medical therapy and 43% underwent additional surgical intervention. Twenty eight day mortality was 29% with concurrent bacteremia found as the sole independent predictor. Similar survival from pulmonary mucormycosis was noted over time.

CONCLUSIONS

Pulmonary mucormycosis is an opportunistic angioinvasive fungal infection. Physicians must have a high level of suspicion in immunocompromised patients with fever and respiratory symptoms refractory to antibiotics. A low threshold should be had for performing an invasive procedure to gain reliable diagnosis, as early, aggressive medical and surgical interventions are needed for successful treatment.

Diagnostic Dilemma in Appendiceal Mucormycosis: A Rare Case Report

Appendiceal mucormycosis is a rare life-threatening infection seen in immunocompromised patients. It is usually seen in chemotherapy induced neutropenia in patients with hematological malignancies. Clinically, the symptoms and signs may be masked due to ongoing corticosteroids. The condition may mimic bacterial appendicitis and the less serious condition, typhlitis. The disease demands prompt surgical debulking and aggressive antifungal treatment. However, surgery is delayed due to the poor performance status and severe neutropenia. This may lead to perforative peritonitis and further dissemination. The survival rates of such disease are dismal. Unfortunately, the diagnosis may be confirmed only on histological examination of the surgically excised tissue. Very few cases have been reported so far. We present here once such a fatal case of appendiceal mucormycosis in a 14-year-old boy who was immunosuppressed due to intensive induction therapy for Acute Myeloblastic Leukemia.

Epidemiological aspects and clinical outcome of patients with Rhinocerebral zygomycosis: a survey in a referral hospital in Iran

Introduction

No comprehensive reports have been published on epidemiological status of Rhinocerebral zygomycosis infections and its outcome in our population, Hence, the current study came to address epidemiological characteristics as well as clinical outcome of patients with Rhinocerebral zygomycosis infection referred to a referral hospital in Iran.

Methods

This retrospective study was performed at the Rasoul-e-Akram hospital, an 800-bed tertiary care teaching hospital in Tehran, Iran. The pathology recorded charts were reviewed to identify all cases of Rhinocerebral zygomycosis from patients admitted between April 2007 and March 2014. A diagnosis of Rhinocerebral zygomycosis was based on histopathological assessments.

Results

Sixty four patients with Rhinocerebral zygomycosis were assessed. The mean age of the patients was 46.07 ± 22.59 years and 51.6% were female. Among those, 67.2% were diabetic, 26.6% were hypertensive and 29.7% had history of cancer. Different sinuses were infected in 73.4% of the patients. Out of all the patients 26.6% underwent surgical procedures and 17.2% were controlled medically. Extensive debridement was carried out in 40.6%. Neutropenia (<1500 cell/ µl) was revealed in 12.5%. In-hospital mortality rate was 35.9% and prolonged hospital stay (> 14 days) was found in 60.9%. According to the Multivariable logistic regression analysis, the main predictors of in-hospital mortality included female gender, advanced age, the presence of sinus infection, and neutropenia, while higher dosages of amphotericin administered had a protective role in preventing early mortality. In a similar Multivariate model, history of cancer could predict prolonged hospital stay, whereas using higher dose of amphotericin could lead to shortening length of hospital stay.

Conclusion

There is no difference in demographic characteristics between our patients with Rhinocerebral zygomycosis and other nations. The presence of diabetes mellitus is closely associated with the presence of this infection. Sinus involvement is very common in those with Rhinocerebral zygomycosis leading to high mortality and morbidity. Besides female gender, advanced age, and presence of neutropenia was a major risk factor for increasing early mortality. The use of higher doses of antifungal treatment such as amphotericin can prevent both mortality and prolonged hospital stay. The cancer patients may need longer hospital stay because of needing comprehensive in-hospital treatment.

Recent developments in the management of invasive fungal infections in patients with oncohematological diseases

Patients with hematological cancer have a high risk of invasive fungal diseases (IFDs). These infections are mostly life threatening and an early diagnosis and initiation of appropriate antifungal therapy are essential for the clinical outcome. Most commonly, Aspergillus and Candida species are involved. However, other non-Aspergillus molds are increasingly be identified in cases of documented IFDs. Important risk factors are long lasting granulocytopenia with neutrophil counts below 500/μl for more than 10 days or graft-versus-host disease resulting from allogeneic stem-cell transplantation. For definite diagnosis of IFD, various diagnostic tools have to be applied, including conventional mycological culture and nonconventional microbiological tests such as antibody/antigen and molecular tests, as well as histopathology and radiology. In the last few years, various laboratory methods, like the Aspergillus GM immunoassay (Aspergillus GM EIA), 1,3-ß-D-glucan (BG) assay or polymerase chain reaction (PCR) techniques have been developed for better diagnosis. Since no single indirect test, including radiological methods, provides the definite diagnosis of an invasive fungal infection, the combination of different diagnostic procedures, which include microbiological cultures, histological, serological and molecular methods like PCR together with the pattern of clinical presentation, may currently be the best strategy for the prompt diagnosis, initiation and monitoring of IFDs. Early start of antifungal therapy is mandatory, but clinical diagnostics often do not provide clear evidence of IFD. Integrated care pathways have been proposed for management and therapy of IFDs with either the diagnostic driven strategy using the preemptive antifungal therapy as opposed to the clinical or empirical driven strategy using the 'traditional' empirical antifungal therapy. Antifungal agents preferentially used for systemic therapy of invasive fungal infections are amphotericin B preparations, fluconazole, voriconazole, posaconazole, caspofungin, anidulafungin, micafungin, and most recently isavuconazole. Clinical decision making must consider licensing status, local experience and availability, pharmacological and economic aspects.

A retrospective analysis of eleven cases of invasive rhino-orbito-cerebral mucormycosis presented with orbital apex syndrome initially

Background

Rhino-orbito-cerebral mucormycosis(ROCM) is an invasive fungal infection that usually occurs in immunocompromised patients and sometimes presents as orbital apex syndrome(OAS) initially. It is rapidly fatal without an early diagnosis and treatment. We report the cases of invasive ROCM presenting with OAS initially in order to raise the attention of clinicians.

Methods

We retrospectively investigated eleven cases of invasive ROCM presenting initially with OAS admitted between January 2006 and December 2013. We analyzed clinical features, results of laboratory and radiological examinations, nasal endoscopy, aggressive surgical excision and debridement, and medical management outcomes of each case.

Results

A total of eleven cases of invasive ROCM with OAS as an initial sign were presented. Mucormycosis was accompanied by type II diabetes mellitus in nine cases, renal transplant in one case, and injury caused by traffic accident in one case. Anterior rhinoscopy revealed palatine or nasal necrotic lesions in all patients, and transethmoidal optic nerve decompression was carried out in three patients at the same time. CT scan revealed rhino-orbital-cerebral involvement in every patient. All patients were given intravenous amphotericin B. Nine patients underwent surgical debridement of necrotic tissue. Three patients survived.

Conclusions

ROCM is a severe, emergent and fatal infection requiring multidisciplinary management. It may often present with OAS initially. For ophthalmologist, mucormycosis must be considered in immunocompromised patients presenting with OAS initially, and anterior rhinoscopy is imperative before hormonotherapy, even in the cases absent of ketoacidosis induced by diabetes mellitus.

Mucormycosis causing maxillary osteomyelitis

Mucormycosis is an opportunistic fungal infection, more commonly observed in immunocompromised patients. The mode of infection is via the inhalation route and infection begins initially in the nose and paranasal sinuses with subsequent invasion into the vascular tissue, eventually leading to thrombosis and necrosis of nearby hard and soft tissues. Here, we report a case of chronic osteomyelitis of the maxillary bone with fungal infection (mucormycosis) and extensive tissue necrosis in an uncontrolled diabetes mellitus patient.

Detection of Mucor velutinosus in a blood culture after autologous peripheral blood stem cell transplantation : a pediatric case report

Filamentous fungi were detected in the blood culture of a one-year-old boy after autologous peripheral blood stem cell transplantation. The patient was suspected to have aspergillosis and received micafungin. Fungi were isolated on potato dextrose agar medium and incubated at 37℃ for 2-5 days. Grayish, cottony colonies formed. A slide culture showed a spherical sporangium at the tips of the sporangiophores. The fungus could have been a zygomycete. The zygomycete was isolated from three blood cultures. The antifungal drug was changed from micafungin to liposomal amphotericin B, which resulted in an improvement in the patient's symptoms. Growth was observed at 37℃, but not 42℃ in a growth temperature test. Gene sequence analysis identified the fungus as Mucor velutinosus. To the best of our knowledge, this is the first time M. velutinosus has been detected in Japan, and this case is very rare. Zygomycetes are known to be pathogens that cause fungal infections in immunodeficient patients such as those with leukemia. They are difficult to identify by culture and are identified at autopsy in many cases. Therefore, culture examinations should be performed for immunodeficient patients with the consideration of zygomycetes.

"An unusual presentation of colonic mucormycosis mimicking carcinoma colon- a surgeon's perspective"

INTRODUCTION

Mucormycosis caused by order mucorales, an ubiquitous saprophytic mold found in soil and organic matter worldwide, is a rare but invasive opportunistic fungal infection. Gastrointestinal mucormycosis is the most uncommon clinical presentation being particularly rare, accounted for 4-7% of all cases.

PRESENTATION OF CASE

We report an unusual presentation of mucormycosis of ascending colon that was simulating carcinoma colon.

DISCUSSION

GI mucormycosis most commonly involves the stomach (57.5%), followed by the colon (32.3%) and the ileum (6.9%). Initial presentations may be abdominal pain and distension, fever, and diarrhoea. Colonic mucormycosis presenting as a mass with altered bowel habit, melena and abdominal pain in our case is extremely difficult to differentiate it from carcinoma colon. A definitive diagnosis of mucormycosis is almost always ascertained by histopathological evidence of fungal invasion of tissue.

CONCLUSION

Knowing these unusual presentations of this disease, surgeon need to maintain a high index of suspicion and perform timely and appropriate diagnostic evaluation to improve patient outcome. Prompt diagnosis, reversal of predisposing conditions, and aggressive surgical debridement remain cornerstones of therapy for this deadly disease.

Disseminated Cunninghamella bertholletiae infection with septic pulmonary embolism after allogeneic bone marrow transplantation

Mucormycosis in immunocompromised patients is often reported. We report a patient who developed non-thrombotic pulmonary embolism due to Cunninghamella bertholletiae after allogeneic stem cell transplantation.

Successful treatment of disseminated mucormycosis in a neutropenic patient with T-cell acute lymphoblastic leukaemia

Mucormycosis is a rare angioinvasive fungal infection, more commonly seen in immunosuppressed patients, with reported mortality rates of 95% in disseminated disease. We present a case report of a patient with T-cell acute lymphoblastic leukaemia who developed disseminated infection with mucormycosis (involving the pancreas, left occipital lobe, right lower lobe of lung, appendix and right kidney) after having completed induction and consolidation chemotherapy. Growth of Lichtheimia corymbifera was initially isolated following a right pleural tap with fungal elements identified repeatedly on subsequent pathology specimens. Following radical surgical debridement and concurrent treatment with combination antifungal therapy, the patient survived. This case demonstrates that aggressive multisite surgical de-bulking of disseminated fungal foci, in conjunction with combination antifungal therapy and reversal of immunosuppression, can result in survival despite the grave prognosis associated with disseminated mucormycosis.

An autopsy case of pulmonary fissure induced by zygomycosis

For immunodeficient patients, fungi are life-threatening pathogens. In this paper, we present an autopsy case of combined zygomycosis and aspergillosis. A female in her 70s on chronic hemodialysis was admitted to a hospital suffering bloody sputum, dyspnea, and fever, probably due to perinuclear anti-neutrophil cytoplasmic antibody-related vasculitis. Antibiotics were administered and immunosuppressive therapy was started, resulting in an improvement in her condition. Pneumonia later developed, followed by pulmonary bleeding and intractable pneumothorax from which she ultimately died. On autopsy, the upper lobe of the left lung was found to have hemorrhagic necrosis and showed a large longitudinal fissure. Microscopically, Zygomycota were observed in both the lungs and heart, while Aspergillus was found in the middle lobe of the right lung. Zygomycosis, which usually has a poor prognosis, is assumed to have induced hemorrhagic infarction of the lungs, inducing pulmonary bleeding and necrosis, despite the use of lipid formulations of amphotericin B, which are effective medicines against Zygomycota.

Risk factors for early mortality in haematological malignancy patients with pulmonary mucormycosis

Pulmonary mucormycosis (PM) is a life-threatening opportunistic mycosis with a variable clinical evolution and few prognostic markers for outcome assessment. Several clinical risk factors for poor outcome present at the diagnosis of PM were analyzed in 75 consecutive hematology patients from 2000-2012. Significant variables (P < 0.1) were entered into a multivariate Cox-proportional hazard regression model adjusting for baseline APACHE II to identify independent risk factors for mortality within 28 days. Twenty-eight of 75 patients died within 4-week follow up. A lymphocyte count < 100/mm³ at the time of diagnosis (adjusted hazard ratio 4.0, 1.7-9.4, P = 0.01) and high level of lactate dehydrogenase (AHR 3.7, 1.3-10.2, P = 0.015) were independent predictors along with APACHE II score for 28-day mortality. A weighted risk score based on these 3 baseline variables accurately identified non-surviving patients at 28 days (area under the receiver-operator curve of 0.87, 0.77-0.93, P < 0.001). A risk score > 22 was associated with 8-fold high rates of mortality (P < 0.0001) within 28 days of diagnosis and median survival of 7 days versus ≥28 days in patients with risk scores ≤22. We found that APACHE II score, severe lymphocytopenia and high LDH levels at the time of PM diagnosis were independent markers for rapid disease progression and death.

Successful surgical and medical treatment of rhizopus osteomyelitis following hematopoietic cell transplantation

Mucormycosis has been reported in otherwise healthy individuals; however, it is primarily seen in immunocompromised patients, such as those with diabetes mellitus, malignancy, or chronic graft-versus-host disease, and has a high mortality rate. Because most cases of mucormycosis are associated with contiguous rhinocerebral infection, only 5 cases of isolated musculoskeletal Rhizopus infection have been reported in the literature. One patient underwent hematopoietic cell transplant, which resulted in a fatal outcome.This article describes the successful treatment of isolated Rhizopus osteomyelitis in a patient who underwent hematopoietic cell transplant using a combined surgical and medical approach. A 33-year-old woman with pre-B cell acute lymphoblastic leukemia underwent hematopoietic cell transplant with few complications but developed chronic graft-versus-host disease 8 months posttransplant. She was treated with high-dose steroids for 6 weeks before she was admitted for severe right tibial pain in the absence of trauma. Early detection, aggressive therapies, and a multidisciplinary surgical and medical team allowed for the microbiologically confirmed resolution of the infection. Treatment included multiagent antimicrobial therapy with amphotericin B, daptomycin, and ertapenem. Several surgical irrigation and debridement procedures were also performed, with the eventual placement of amphotericin-impregnated polymethylmethacrylate cement beads and small fragment titanium screws. The patient continued taking postoperative antifungal treatment for 7 months after discharge. Six months following the discontinuation of antifungal therapy, the team's multidisciplinary approach achieved a continued resolution of the patient's infection and a return to a fully ambulatory and radiographically proven recovery without limb loss.