Mortality in hematologic malignancy and hematopoietic stem cell transplant patients with mucormycosis, 2001 to 2009

Risk Factors and Outcomes of Mucorales Infection in a Modern Cohort of Solid Organ Transplant, Hematopoietic Cell Transplant, and Chimeric Antigen Receptor T-cell Therapy Recipients

BACKGROUND

Mucorales infections continue to cause significant morbidity and mortality in immunocompromised hosts despite the advent of new approaches for diagnosis and treatment of fungal infections. We aimed to evaluate risk factors and outcomes of Mucorales infection in solid organ transplant, hematopoietic cell transplant, and chimeric antigen receptor T-cell therapy recipients.

METHODS

This single-center retrospective study included solid organ transplant, hematopoietic cell transplant, and chimeric antigen receptor T-cell patients with cultures positive for Mucorales.

RESULTS

Forty-three patients were included for analysis; 34 solid organ transplant (79%) and 9 hematopoietic stem cell transplant or chimeric antigen receptor T-cell (21%). Infection with Mucorales occurred a median of 184 days after transplant. At the time of diagnosis, 36 patients were on antifungal prophylaxis with the majority receiving posaconazole (53%). Thirty-three had clinically significant disease; 30 received definitive anti-Mucorales therapy and 3 empiric antifungal therapy. Isavuconazole was the most common azole used for treatment in monotherapy recipients. All-cause mortality was 64% and, of these deaths, 18 (75%) were directly related to Mucormycosis. The highest mortality was seen in disseminated and intra-abdominal disease (100%), followed by pulmonary disease (50%). There was no significant association with mortality and transplant type or number of immunosuppressive agents.

CONCLUSION

Mucormycosis is an important cause of morbidity and mortality in immunocompromised patients. Breakthrough infection was not uncommon in this study. Data regarding the incidence of infection at approximately 6 months after transplantation can inform prophylaxis and treatment regimens. The spectrum of antifungal regimens used reflects the lack of consensus on ideal regimens for these organisms and a need for more studies.

Rate, Risk Factors, and Outcomes of Invasive Fungal Infections in Patients with Hematologic Malignancies

Background: Invasive fungal infections (IFIs) are a significant cause of mortality and morbidity in patients with hematological malignancies. Given the considerable prevalence and consequences of IFIs, hence revealing the exact cause of fungal infections, their rate, associated risk factors, and complications could contribute to reducing both financial and life costs, choosing targeted antifungal treatment, and avoiding unnecessary toxic treatments in individuals who are not suffering from mycoses. Materials and Methods: This prospective cross-sectional study was conducted in the first semester of 2019. All patients with hematologic malignancies (HM) admitted to Dr. Shariati Hospital were studied. Only those with probable/proven IFIs defined according to the last update of EORTC/MSG criteria were included in the study. The demographic and clinical data were recorded from the hospital information registration system using a questionnaire. Statistical analysis was performed using SPSS software version 24. Results: Out of 1109 HM patients hospitalized during the study period, 67 (6.04%) IFIs were diagnosed. Of these, 57 (85.04%) were aspergillosis, 7 (10.4%) were mucormycosis, and 3 patients developed other fungal infections. Males constituted 67.2% of the entire IFI population. The mean±SD age of the samples was 43.16 ± 13.8 years. The most common type of malignancy was AML. Lung imaging showed lesions associated with fungal infections in 52 cases (77.6%), with multiple nodules as the most prevalent pattern being observed in 64.2% of cases. Sinus involvement was evidenced in the PNS CT scan of 46 (68.6%) patients. The attributable mortality rate for IFIs was 62.7%. Both the types of IFI and malignancies had no significant relationship with the outcome of patients. Central venous catheter, mucositis, and antibiotic use were the most frequent risk factors. Conclusion:  IFI represents a frequent complication for HM patients with high mortality. Aspergillus species are the predominant etiology in these settings. Considering our results, in high-risk patients, manifestations of warning signs in the sinus and lungs, which would not be cleared despite receiving antibiotics, should raise the possibility of IFIs.

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.

Amphotericin B colloidal dispersion: an effective drug for the treatment of mucormycosis in China

Objective

Mucormycosis has emerged as an increasingly important cause of morbidity and mortality in immunocompromised patients, but the effective drugs for the treatment are limited. Hence, the study aimed to summarize the characteristics of mucormycosis in patients with hematological malignancies, and investigate the efficacy and safety of Amphotericin B Colloidal Dispersion (ABCD) in treating mucormycosis.

Methods

In this study, patients with mucormycosis complicated by hematological malignancies who received ABCD at the First Affiliated Hospital of Zhengzhou University from April 2021 to May 2022 were retrospectively enrolled. The clinical data of the enrolled patients were collected, and then, the drug response at 2 weeks, 4 weeks, and the end of treatment; the survival rate at 4, 8, and 12 weeks; and the laboratory-related indicators and adverse events (AEs) associated with ABCD were evaluated.

Results

In total, 9 patients with mucormycosis complicated by hematological malignancies were enrolled. The main symptoms were fever, cough, and chest pain. In addition, reversed halo signs (RHS) were found on chest CTs. The responses to ABCD at 2 weeks, 4 weeks, and the end of treatment were 100% (9/9), 77.8% (7/9), and 77.8% (7/9), respectively. The survival rates of the patients at 4, 8, and 12 weeks were 77.8% (7/9), 66.7% (6/9), and 66.7% (6/9), respectively. Among laboratory-related indicators, white blood cell (WBC) counts were significantly increased from baseline after 1 and 2 weeks of ABCD treatment (P<0.05), whereas neutrophil counts were only increased significantly from baseline at 2 weeks post-treatment (P<0.05). The most common AEs were infusion-related AEs manifesting as fever, chills, and pruritus. Moreover, none of the patients suffered from renal injury once again.

Conclusion

ABCD is a promising treatment strategy for patients with mucormycosis complicated by hematologic malignancies, showing remarkable efficacy and safety.

Evolution of antifungals for invasive mold infections in immunocompromised hosts, then and now

INTRODUCTION

The current armamentarium of antifungal agents for invasive mold infections (IMI) has dramatically improved over the last 50 years. Existing therapies are, however, associated with toxicities, drug interactions, and in some cases, therapeutic failures. Novel antifungals are needed to address the increasing prevalence of IMI and the growing threat of antifungal resistance.

AREAS COVERED

We review the history and development of the most commonly used antifungals. We discuss the current consensus guidelines and supporting data for treatment of invasive mold infection (IMI), the role of susceptibility testing, and the niche that novel antifungals could fill. We review the current data for aspergillosis, mucormycosis, and hyalohyphomycosis.

EXPERT OPINION

Robust clinical trial data demonstrating the relative effectiveness of our current antifungal agents for treating IMI outside of A. fumigatus remains limited. Clinical trials are urgently needed to delineate the relationship between MICs and clinical outcomes for existing agents and to better evaluate the invitro and in-vivo aspects of antifungal synergy. Continued international multicenter collaboration and standardized clinical endpoints for trials evaluating both existing and new agents is necessary to advance the field.

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.

[Invasive mucormycosis affecting maxillofacial region in oncohematological patients undergoing chemotherapeutic treatment and transplantation of hematopoietic stem cells]

The aim of the work is to attract the attention of specialists: dentists, oncologists, hematologists to thorough sanitation of the oral cavity of patients preparing for chemotherapy treatment, to transplantation of hematopoietic stem cells. Two clinical cases described in the article were observed at the R.M. Gorbacheva First Saint-Petersburg State Medical University from 2010 to 2019. They confirm the possibility of the occurrence of infectious complications with damage to the maxillofacial region caused by rare pathogens of invasive mycosis, which debuted as an odontogenic inflammatory process. The success of the treatment of Invasive Mycosis depends on early diagnosis and antimycotic therapy; active surgical tactics in relation to the affected tissues in a controlled course of the underlying disease and the restoration of effective hematopoiesis.

Coinfection pulmonary mucormycosis and aspergillosis with disseminated mucormycosis involving gastrointestinalin in an acute B-lymphoblastic leukemia patient

Pulmonary mucormycosis and aspergillosis with disseminated mucormycosis involving gastrointestinalin is a very rare but lethal infection leading to extreme mortality. Herein, we present a unique case of pulmonary coinfection with Cunninghamella bertholletiae and Aspergillus flavus, with disseminated mucormycosis involving the jejunum caused by C. bertholletiae in an acute B-lymphocytic leukemia (B-ALL) patient with familial diabetes. Early administration of active antifungal agents at optimal doses and complete resection of all infected tissues led to improved therapeutic outcomes.

[Mucormycosis: Current and future management perspective]

Infections caused by mucorales, with an increasing incidence after candidiasis and aspergillosis, are characterized by the fast angioinvasion of blood vessels and invasion of neighboring organs or structures. Mucorales most commonly cause rhinocerebral, pulmonary, cutaneous, digestive or disseminated infections, and their spread is favored by certain underlying diseases (diabetes, kidney failure) and risk factors (neutropenia, immunosuppression, iron overload). These infections have a high mortality rate, over 40% in many series, and the key to their cure depends on both an early diagnosis and an antifungal treatment, associated in most cases with extensive surgical debridement and other adjunctive therapies. Currently, there are international guidelines, not only local ones, for the management of mucormycosis, in which it is considered by consensus and with a strong recommendation that first-line treatment with high-dose liposomal amphotericin B is the best choice. The combined antifungal treatment of polyene agents with triazoles or candins remains in open debate.

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.

Galleria mellonella as a model system to study virulence potential of mucormycetes and evaluation of antifungal treatment

Mucorales can cause cutaneous to deep-seated infections, mainly in the immunocompromised host, resulting in high mortality rates due to late and inefficient treatment. In this study, Galleria mellonella larvae were evaluated as a heterologous invertebrate host to study pathogenicity of clinically relevant mucormycetes (Rhizopus spp., Rhizomucor spp., Lichtheimia spp., Mucor spp.). All tested species were able to infect G. mellonella larvae. Virulence potential was species-specific and correlated to clinical relevance. Survival of infected larvae was dependent on (a) the species (growth speed and spore size), (b) the infection dose, (c) the incubation temperature, (d) oxidative stress tolerance, and (e) iron availability in the growth medium. Moreover, we exploited the G. mellonella system to determine antifungal efficacy of liposomal amphotericin B, posaconazole, isavuconazole, and nystatin-intralipid. Outcome of in vivo treatment was strongly dependent upon the drug applied and the species tested. Nystatin-intralipid exhibited best activity against Mucorales, followed by posaconazole, while limited efficacy was seen for liposomal amphotericin B and isavuconazole. Pharmacokinetic properties of the tested antifungals within this alternative host system partly explain the limited treatment efficacy. In conclusion, G. mellonella represents a useful invertebrate infection model for studying virulence of mucormycetes, while evaluation of treatment response was limited.

Challenges in the diagnosis and treatment of mucormycosis

The diagnosis and treatment of mucormycosis are challenging. The incidence of the disease seems to be increasing. Hematological malignancies are the most common underlying disease in countries with high income and uncontrolled diabetes in developing countries. Clinical approach to diagnosis lacks sensitivity and specificity. Radiologically, multiple (≥10) nodules and pleural effusion are reportedly associated with pulmonary mucormycosis. Another finding on computerized tomography (CT) scan, which seems to indicate the presence of mucormycosis, is the reverse halo sign. Microscopy (direct and on histopathology) and culture are the cornerstones of diagnosis. Molecular assays can be used either for detection or identification of mucormycetes, and they can be recommended as valuable add-on tools that complement conventional diagnostic procedures. Successful management of mucormycosis is based on a multimodal approach, including reversal or discontinuation of underlying predisposing factors, early administration of active antifungal agents at optimal doses, complete removal of all infected tissues, and use of various adjunctive therapies. Our armamentarium of antifungals is slightly enriched by the addition of two newer azoles (posaconazole and isavuconazole) to liposomal amphotericin B, which remains the drug of choice for the initial antifungal treatment, according to the recently published guidelines by ECIL-6, as well as those published by ECMM/ESCMID. Despite the efforts for better understanding of the pathogenesis, early diagnosis and aggressive treatment of mucormycosis, the mortality rate of the disease remains high.

Generation of A Mucor circinelloides Reporter Strain-A Promising New Tool to Study Antifungal Drug Efficacy and Mucormycosis

Invasive fungal infections caused by Mucorales (mucormycosis) have increased worldwide. These life-threatening infections affect mainly, but not exclusively, immunocompromised patients, and are characterized by rapid progression, severe tissue damage and an unacceptably high rate of mortality. Still, little is known about this disease and its successful therapy. New tools to understand mucormycosis and a screening method for novel antimycotics are required. Bioluminescent imaging is a powerful tool for in vitro and in vivo approaches. Hence, the objective of this work was to generate and functionally analyze bioluminescent reporter strains of Mucor circinelloides, one mucormycosis-causing pathogen. Reporter strains were constructed by targeted integration of the firefly luciferase gene under control of the M. circinelloides promoter Pzrt1. The luciferase gene was sufficiently expressed, and light emission was detected under several conditions. Phenotypic characteristics, virulence potential and antifungal susceptibility were indifferent to the wild-type strains. Light intensity was dependent on growth conditions and biomass, being suitable to determine antifungal efficacy in vitro. This work describes for the first time the generation of reporter strains in a basal fungus that will allow real-time, non-invasive infection monitoring in insect and murine models, and the testing of antifungal efficacy by means other than survival.

Pulmonary Infections in Immunocompromised Hosts: Clinical

Pulmonary infections in immunocompromised patients remain a significant contributor to mortality, morbidity, and health care-associated costs in such a vulnerable patient population. Their epidemiology is changing, set forth by new trends in immunosuppressive regimens and also prophylaxis. The host characteristics, presenting clinical symptomatology, along with radiographic patterns, have also evolved. The microbiology diagnostics are now enriched with nonculture methods for better identification of the causative pathogens. Chest imaging remains the cornerstone of the initial workup. Our article will examine the new trends in epidemiology, clinical findings, and diagnostics for immunocompromised patients with pulmonary infections (transplant recipients, neutropenic hosts, HIV-infected patients, and patients with autoimmune conditions). We will also review the differential diagnosis that most of the times includes malignancies and drug or radiation-related toxicities.

Fungal Pneumonia in Patients with Hematologic Malignancy and Hematopoietic Stem Cell Transplantation

Fungal pneumonias cause unacceptable morbidity among patients with hematologic malignancies (HM) and recipients of hematopoietic stem cell transplantation (HSCT). The high incidence of fungal pneumonias in HM/HSCT populations arises from their frequently severe, complex, and persistent immune dysfunction caused by the underlying disease and its treatment. The cytopenias, treatment toxicities, and other immune derangements that make patients susceptible to fungal pneumonia frequently complicate its diagnosis and increase the intensity and duration of antifungal therapy. This article addresses the host factors that contribute to susceptibility, summarizes diagnostic recommendations, and reviews current guidelines for management of fungal pneumonia in patients with HM/HSCT.

Clinical evaluation of a Mucorales-specific real-time PCR assay in tissue and serum samples

Molecular diagnostic assays can accelerate the diagnosis of fungal infections and subsequently improve patient outcomes. In particular, the detection of infections due to Mucorales is still challenging for laboratories and physicians. The aim of this study was to evaluate a probe-based Mucorales-specific real-time PCR assay (Muc18S) using tissue and serum samples from patients suffering from invasive mucormycosis (IMM). This assay can detect a broad range of clinically relevant Mucorales species and can be used to complement existing diagnostic tests or to screen high-risk patients. An advantage of the Muc18S assay is that it exclusively detects Mucorales species allowing the diagnosis of Mucorales DNA without sequencing within a few hours. In paraffin-embedded tissue samples this PCR-based method allowed rapid identification of Mucorales in comparison with standard methods and showed 91 % sensitivity in the IMM tissue samples. We also evaluated serum samples, an easily accessible material, from patients at risk from IMM. Mucorales DNA was detected in all patients with probable/proven IMM (100 %) and in 29 % of the possible cases. Detection of IMM in serum could enable an earlier diagnosis (up to 21 days) than current methods including tissue samples, which were gained mainly post-mortem. A screening strategy for high-risk patients, which would enable targeted treatment to improve patient outcomes, is therefore possible.

Filamentous Fungi

Filamentous mycoses are often associated with significant morbidity and mortality. Prompt diagnosis and aggressive treatment are essential for good clinical outcomes in immunocompromised patients. The host immune response plays an essential role in determining the course of exposure to potential fungal pathogens. Depending on the effectiveness of immune response and the burden of organism exposure, fungi can either be cleared or infection can occur and progress to a potentially fatal invasive disease. Nonspecific cellular immunity (i.e., neutrophils, natural killer [NK] cells, and macrophages) combined with T-cell responses are the main immunologic mechanisms of protection. The most common potential mold pathogens include certain hyaline hyphomycetes, endemic fungi, the Mucorales , and some dematiaceous fungi. Laboratory diagnostics aimed at detecting and differentiating these organisms are crucial to helping clinicians make informed decisions about treatment. The purpose of this chapter is to provide an overview of the medically important fungal pathogens, as well as to discuss the patient characteristics, antifungal-therapy considerations, and laboratory tests used in current clinical practice for the immunocompromised host.

Susceptibility profiles of amphotericin B and posaconazole against clinically relevant mucorales species under hypoxic conditions

The effect of hypoxic conditions on the in vitro efficacy of amphotericin B and posaconazole against Mucorales was evaluated by defining MICs with Etest and broth microdilution and identifying minimal fungicidal concentrations (MFCs). With Etest, oxygen-dependent changes were detected, while the MIC and the MFC determined with broth microdilution remained unaltered with reduced oxygen levels. The observed differences depended on the method used.

Stability in the cumulative incidence, severity and mortality of 101 cases of invasive mucormycosis in high-risk patients from 1995 to 2011: a comparison of eras immediately before and after the availability of voriconazole and echinocandin-amphotericin combination therapies

As invasive mucormycosis (IM) numbers rise, clinicians suspect prior voriconazole worsens IM incidence and severity, and believe combination anti-fungal therapy improves IM survival. To compare the cumulative incidence (CI), severity and mortality of IM in eras immediately before and after the commercial availability of voriconazole all IM cases from 1995 to 2011 were analysed across four risk-groups (hematologic/oncologic malignancy (H/O), stem cell transplantation (SCT), solid organ transplantation (SOT) and other), and two eras, E1 (1995-2003) and E2, (2004-2011). Of 101 IM cases, (79 proven, 22 probable): 30 were in E1 (3.3/year) and 71 in E2 (8.9/year). Between eras, the proportion with H/O or SCT rose from 47% to 73%, while 'other' dropped from 33% to 11% (P = 0.036). Between eras, the CI of IM did not significantly increase in SCT (P = 0.27) or SOT (P = 0.30), and patterns of anatomic location (P = 0.122) and surgical debridement (P = 0.200) were similar. Significantly more patients received amphotericin-echinocandin combination therapy in E2 (31% vs. 5%, P = 0.01); however, 90-day survival did not improve (54% vs. 59%, P = 0.67). Since 2003, the rise of IM reflects increasing numbers at risk, not prior use of voriconazole. Frequent combination of anti-fungal therapy has not improved survival.

Mold infections of the central nervous system

The recent outbreak of exserohilum rostratum meningitis linked to epidural injections of methylprednisolone acetate has brought renewed attention to mold infections of the central nervous system (CNS). Although uncommon, these infections are often devastating and difficult to treat. This focused review of the epidemiologic aspects, clinical characteristics, and treatment of mold infections of the CNS covers a group of common pathogens: aspergillus, fusarium, and scedosporium species, molds in the order Mucorales, and dematiaceous molds. Infections caused by these pathogen groups have distinctive epidemiologic profiles, clinical manifestations, microbiologic characteristics, and therapeutic implications, all of which clinicians should understand.

Hospital days, hospitalization costs, and inpatient mortality among patients with mucormycosis: a retrospective analysis of US hospital discharge data

Background

Mucormycosis is a rare and potentially fatal fungal infection occurring primarily in severely immunosuppressed patients. Because it is so rare, reports in the literature are mainly limited to case reports or small case series. The aim of this study was to evaluate inpatient mortality, length of stay (LOS), and costs among a matched sample of high-risk patients with and without mucormycosis in a large nationally representative database.

Methods

We conducted a retrospective analysis using the 2003–2010 Healthcare Cost and Utilization Project – Nationwide Inpatient Sample (HCUP-NIS). The NIS is a nationally representative 20% sample of hospitalizations from acute care United States (US) hospitals, with survey weights available to compute national estimates. We classified hospitalizations into four mutually exclusive risk categories for mucormycosis: A- severely immunocompromised, B- critically ill, C- mildly/moderately immunocompromised, D- major surgery or pneumonia. Mucormycosis hospitalizations (“cases”) were identified by ICD-9-CM code 117.7. Non-mucormycosis hospitalizations (“non-cases”) were propensity-score matched to cases 3:1. We examined demographics, clinical characteristics, and hospital outcomes (mortality, LOS, costs). Weighted results were reported.

Results

From 319,366,817 total hospitalizations, 5,346 cases were matched to 15,999 non-cases. Cases and non-cases did not differ significantly in age (49.6 vs. 49.7 years), female sex (40.5% vs. 41.0%), White race (53.3% vs. 55.9%) or high-risk group (A-49.1% vs. 49.0%, B-20.0% vs. 21.8%, C-25.5% vs. 23.8%, D-5.5% vs. 5.4%). Cases experienced significantly higher mortality (22.1% vs. 4.4%, P < 0.001), with mean LOS and total costs more than 3-fold higher (24.5 vs. 8.0 days and $90,272 vs. $25,746; both P < 0.001).

Conclusions

In a national hospital database, hospitalizations with mucormycosis had significantly higher inpatient mortality, LOS, and hospital costs than matched hospitalizations without mucormycosis. Findings suggest that interventions to prevent or more effectively treat mucormycosis are needed.

Green herring syndrome: bacterial infection in patients with mucormycosis cavitary lung disease

Mucormycosis is a life-threatening fungal disease in patients with hematological malignancies. The diagnosis of pulmonary mucormycosis is particularly challenging. We describe 3 mucormycosis cases with an uncommon presentation in patients whose cavitary lung disease was attributed to well documented bacterial infection, although evolution and reassessment established mucormycosis as the underlying disease.

Isavuconazole treatment of a patient with disseminated mucormycosis

We report a patient with relapsed acute myelogenous leukemia after allogeneic stem cell transplantation who developed disseminated mucormycosis due to Rhizomucor pusillus/R. miehei involving lung, brain, and skin. After failing posaconazole and being intolerant to amphotericin, he was treated effectively with isavuconazole for over 6 months despite ongoing treatment for relapsed leukemia.

Epidemiology and treatment of mucormycosis

Mucormycosis is an uncommon but aggressive opportunistic fungal infection that afflicts patients with severe underlying immunosuppression, uncontrolled hyperglycemia and/or ketoacidosis, patients with iron overload resulting from frequent blood transfusions or blood disorders and occasionally healthy patients who are inoculated with fungal spores through traumatic injuries. The clinical presentation of mucormycosis is initially indistinguishable from other common infections, and if not diagnosed early and aggressively treated, it is almost always fatal. In this article we summarize recent changes in the epidemiology of mucormycosis, discuss diagnostic and clinical clues suggestive of the infection and provide a general strategy for managing the infection in the absence of data from well-controlled, prospective clinical trials.

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.

Pulmonary fungal infections

This review details some of the advances that have been made in the recent decade in the diagnosis, treatment and epidemiology of pulmonary fungal infections. These advances have occurred because of increasing knowledge regarding the fungal genome, better understanding of the structures of the fungal cell wall and cell membrane and the use of molecular epidemiological techniques. The clinical implications of these advances are more rapid diagnosis and more effective and less toxic antifungal agents. For example, the diagnosis of invasive pulmonary aspergillosis, as well as histoplasmosis and blastomycosis, has improved with the use of easily performed antigen detection systems in serum and bronchoalveolar lavage fluid. Treatment of angioinvasive moulds has improved with the introduction of the new azoles, voriconazole and posaconazole that have broad antifungal activity. Amphotericin B is less frequently used, and when used is often given as lipid formulation to decrease toxicity. The newest agents, the echinocandins, are especially safe as they interfere with the metabolism of the fungal cell wall, a structure not shared with humans cells. Epidemiological advances include the description of the emergence of Cryptococcus gattii in North America and the increase in pulmonary mucormycosis and pneumonia due to Fusarium and Scedosporium species in transplant recipients and patients with haematological malignancies. The emergence of azole resistance among Aspergillus species is especially worrisome and is likely related to increased azole use for treatment of patients, but also to agricultural use of azoles as fungicides in certain countries.

Tacrolimus enhances the potency of posaconazole against Rhizopus oryzae in vitro and in an experimental model of mucormycosis

BACKGROUND

We hypothesized that tacrolimus, an inhibitor of the calcineurin pathway, would enhance the in vivo activity of posaconazole against Rhizopus oryzae, the Mucorales species most commonly associated with mucormycosis.

METHODS

We examined patterns of growth inhibition and fungicidal activity of posaconazole and tacrolimus, alone and in combination, against R. oryzae in vitro, using multiple methods (ie, hyphal metabolic and fluorescent vital dye reduction assays and measurement of chitin concentrations), and in vivo, using 2 mucormycosis models: an invertebrate model (Drosophila) and a nonlethal murine model of cutaneous mucormycosis.

RESULTS

Combinations of posaconazole and tacrolimus were synergistic in checkerboard assays for 4 clinical isolates of R. oryzae (48-hour fractional inhibitory concentration index, 0.187-0.281). Pharmacodynamic analysis of the combination revealed that the 90% effective concentration threshold of posaconazole activity against R. oryzae could be achieved with 2-fold lower drug concentrations (0.5-1 mg/L) when administered with tacrolimus (0.007-2 mg/L). In vivo, combination therapy was associated with improved survival in the fly model of mucormycosis (65% vs 57% posaconazole alone) and with significant reductions in cutaneous lesions and R. oryzae fungal burden, compared with animals that received posaconazole monotherapy, in the cutaneous model of mucormycosis.

CONCLUSIONS

Combination posaconazole-tacrolimus therapy displays synergism in vitro and improved antifungal efficacy in vivo in 2 phylogenetically distinct models of mucormycosis.

Diagnosis of pulmonary mucormycosis aiding the diagnosis of small cell lung cancer

Mucormycosis is a rare complication in immunocompromised patients. Antemortem diagnosis of mucormycosis is difficult and often incorrect. We report a case of pulmonary mucormycosis caused by Cunninghamella bertholletiae in an elderly man with interstitial pneumonia. The diagnosis of mucormycosis was established by bronchoalveolar lavage. A coexisting immune deficiency condition was considered. Lung cancer was suspected because of an elevated progastrin-releasing peptide level and bilateral hilar and mediastinal lymphadenopathy; it was diagnosed after performing endoscopic ultrasound-guided fine-needle aspiration. Treatment by intravenous liposomal amphotericin B was effective, but relapse occurred because of bone marrow suppression caused by chemotherapy for lung cancer. Treatment for mucormycosis was resumed, but the patient died of carcinomatous lymphangiosis. Autopsy confirmed the diagnosis of pulmonary mucormycosis and revealed refractory anaemia with small cell lung cancer. Mucormycosis often occurs in immunocompromised patients, but this case is rare because the mucormycosis was diagnosed before the diagnosis of malignancy. Because prognosis is often poor, the possibility of coexisting malignancies should always be investigated in patients with mucormycosis infections.