Epidemiology and clinical manifestations of mucormycosis

An unusual ulcer: A case of cutaneous mucormycosis caused by Rhizopus oryzae

Mucormycoses are high-mortality infections feared by clinicians worldwide. They predominantly affect immunocompromised hosts and are associated with a spectrum of disease. We describe a case of cutaneous mucormycosis caused by Rhizopus oryzae in a patient with multiple risk factors cured with complete surgical excision and a short course of antifungal therapy.

Risk factors for invasive fusariosis in patients with acute myeloid leukemia and in hematopoietic cell transplant recipients

BACKGROUND

Risk factors for invasive fusariosis (IF) have not been characterized. We attempted to identify risk factors for IF in a prospective cohort of hematologic patients treated in 8 centers in Brazil.

METHODS

Patients with (cases) and without (controls) proven or probable IF diagnosed in a cohort of patients with acute myeloid leukemia (AML) or myelodysplasia (MDS), and in allogeneic hematopoietic cell transplant (HCT) recipients (early, until day 40; late, after day 40 posttransplant) were compared by univariate Cox regression analysis.

RESULTS

Among 237 induction remission courses of AML/MDS and 663 HCTs (345 allogeneic and 318 autologous), 25 cases of IF were diagnosed. In the AML/MDS cohort, active smoking (hazard ratio [HR], 9.11 [95% confidence interval {CI}, 2.04-40.71]) was associated with IF. Variables associated with IF in the early phase of allogeneic HCT were receipt of antithymocyte globulin (HR, 22.77 [95% CI, 4.85-101.34]), hyperglycemia (HR, 5.17 [95% CI, 1.40-19.11]), center 7 (HR, 5.15 [95% CI, 1.66-15.97]), and AML (HR, 4.38 [95% CI, 1.39-13.81]), and in the late phase were nonmyeloablative conditioning regimen (HR, 35.08 [95% CI, 3.90-315.27]), grade III/IV graft-vs-host disease (HR, 16.50 [95% CI, 2.67-102.28]), and previous invasive mold disease (HR, 10.65 [95% CI, 1.19-95.39]).

CONCLUSIONS

Attempts to reduce the risk of IF may include smoking cessation, aggressive control of hyperglycemia, and the use of a mold-active agent as prophylaxis in patients receiving nonmyeloablative HCT or ATG in the conditioning regimen. Future research should further explore smoking and other prehospital variables as risks for IF.

Invasive mold infections in solid organ transplant recipients

Invasive mold infections represent an increasing source of morbidity and mortality in solid organ transplant recipients. Whereas there is a large literature regarding invasive molds infections in hematopoietic stem cell transplants, data in solid organ transplants are scarcer. In this comprehensive review, we focused on invasive mold infection in the specific population of solid organ transplant. We highlighted epidemiology and specific risk factors for these infections and we assessed the main clinical and imaging findings by fungi and by type of solid organ transplant. Finally, we attempted to summarize the diagnostic strategy for detection of these fungi and tried to give an overview of the current prophylaxis treatments and outcomes of these infections in solid organ transplant recipients.

Dual disseminated infection with Nocardia farcinica and Mucor in a patient with systemic lupus erythematosus: a case report

INTRODUCTION

Infections remain a major cause of morbidity and mortality in immunocompromised patients and require early diagnosis and treatment. However, correct diagnosis and treatment are often delayed by a multitude of factors. We report what we believe to be the first case of a combined disseminated infection with Nocardia and Mucor in a patient with systemic lupus erythematosus.

CASE PRESENTATION

A 74-year-old Caucasian woman with systemic lupus erythematosus presented with recurrent pneumonia. Despite empirical treatment with antibiotics, her condition gradually deteriorated. Microbiological sampling by thoracoscopy revealed the presence of Nocardia. Despite the institution of therapy for disseminated nocardiosis, she died of multi-organ failure. A post-mortem investigation confirmed nocardiosis, but showed concomitant disseminated mucormycosis infection as well.

CONCLUSION

Members of the bacterial genus Nocardia and the fungal genus Mucor are ubiquitous in the environment, have the ability to spread to virtually any organ, and are remarkably resistant to appropriate therapy. Both pathogens can mimic other pathologies both on clinical and radiological investigations. Invasive sampling procedures are often needed to prove their presence. Establishing a timely, correct diagnosis and a specific treatment is essential for patient survival.

Gastrointestinal mucormycosis requiring surgery in adults with hematologic malignant tumors: literature review

BACKGROUND

Gastrointestinal mucormycosis is associated with high mortality rates. Appropriate and early antifungal therapy and prompt surgical intervention are essential.

METHOD

Case report and literature review.

RESULTS

Nineteen case reports were reviewed describing adults with hematologic malignant tumors who developed intestinal mucormycosis and underwent surgery. The overall survival rate was 50%.

CONCLUSION

Intestinal mucormycosis is an infection associated with a high mortality rate although adults with underlying hematologic malignant have improved outcomes compared with other groups.

Sudden death in a patient with bone marrow transplant by a fungus among us

Mucormycosis is rare, presenting as breakthrough infection among haematological and transplant patients on prophylaxis with voriconazole. We report an unusual presentation of this infection, that which is pneumonia progressing to cardiac arrest. A 68-year-old woman with refractory acute myelogenous leukaemia on voriconazole prophylaxis was initially admitted for neutropenic fever and pneumonia. She was discharged improved on antibiotics and voriconazole for presumed aspergillosis. She returned after 1 month with the same presentation. She eventually improved on antibiotics and voriconazole, and eventually received bone marrow transplantation. Three days later, she developed pleuritic chest pain, dyspnoea, and hypoxia requiring intubation. An hour after intubation, the patient arrested and expired. Autopsy revealed Rhizopus pneumonitis with pulmonary infarction, and emboli to her cerebellum, heart, thyroid and kidney. Mucormycosis is an emerging, fatal infection that should be suspected in haematological and transplant patients who deteriorate on voriconazole.

Human Fungal Pathogens of Mucorales and Entomophthorales

In recent years, we have seen an increase in the number of immunocompromised cohorts as a result of infections and/or medical conditions, which has resulted in an increased incidence of fungal infections. Although rare, the incidence of infections caused by fungi belonging to basal fungal lineages is also continuously increasing. Basal fungal lineages diverged at an early point during the evolution of the fungal lineage, in which, in a simplified four-phylum fungal kingdom, Zygomycota and Chytridiomycota belong to the basal fungi, distinguishing them from Ascomycota and Basidiomycota. Currently there are no known human infections caused by fungi in Chytridiomycota; only Zygomycotan fungi are known to infect humans. Hence, infections caused by zygomycetes have been called zygomycosis, and the term "zygomycosis" is often used as a synonym for "mucormycosis." In the four-phylum fungal kingdom system, Zygomycota is classified mainly based on morphology, including the ability to form coenocytic (aseptated) hyphae and zygospores (sexual spores). In the Zygomycota, there are 10 known orders, two of which, the Mucorales and Entomophthorales, contain species that can infect humans, and the infection has historically been known as zygomycosis. However, recent multilocus sequence typing analyses (the fungal tree of life [AFTOL] project) revealed that the Zygomycota forms not a monophyletic clade but instead a polyphyletic clade, whereas Ascomycota and Basidiomycota are monophyletic. Thus, the term "zygomycosis" needed to be further specified, resulting in the terms "mucormycosis" and "entomophthoramycosis." This review covers these two different types of fungal infections.

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.

Clinical relevance of mold culture positivity with and without recurrent wound necrosis following combat-related injuries

BACKGROUND

Invasive fungal wound infections (IFIs) are a recognized threat for personnel who sustain combat-related blast trauma in Afghanistan. Blast trauma, particularly when dismounted, has wounds contaminated with organic debris and potential for mold infection. Trauma-associated IFI is characterized by recurrent wound necrosis on serial debridement with histologic evidence of invasive molds and/or fungal culture growth. Wounds with mold growth but lacking corresponding recurrent necrosis present a clinical dilemma of whether to initiate antifungal treatment. Our objective was to assess the clinical significance of fungal culture growth without recurrent wound necrosis.

METHODS

US military personnel wounded during combat in Afghanistan (June 2009 to August 2011) were assessed for growth of mold from wound cultures and/or histopathologic evidence of IFI. Identified patients were stratified based on clinical wound appearance (with/without recurrent necrosis), and the resultant groups were compared for injury characteristics, clinical management, and outcomes.

RESULTS

A total of 96 patients were identified: 77 with fungal elements on histopathology and/or fungal growth plus recurrent wound necrosis and 19 with fungal growth on culture but no wound necrosis after initial debridements. Injury patterns and severity were similar between the groups. Patients with recurrent necrosis had more frequent fevers and leukocytosis during the first 2 weeks after injury, and the majority received antifungal therapy compared with only three patients (16%) without recurrently necrotic wounds. Overall, patients without recurrent wound necrosis had significantly less operative procedures (p = 0.02), shorter stay in the intensive care unit (p < 0.01), and lower rates of high-level amputations (5% vs. 20%) and deaths (none vs. 8%) despite no or infrequent antifungal use.

CONCLUSION

The finding of molds on wound culture among patients with blast trauma in the absence of recurrently necrotic wounds on serial debridement does not require systemic antifungal chemotherapy.

LEVEL OF EVIDENCE

Therapeutic study, level IV. Prognosti/epidemiologic study, level III.

Lingual necrosis caused by mucormycosis in a patient with aplastic anaemia: case report

Mucormycosis is a rare but aggressive fungal infection that predominantly affects immunocompromised patients. We report a case that highlights the importance of knowledge to enable prompt diagnosis and management of an otherwise fatal phenomenon.

Successful therapy of progressive rhino-orbital mucormycosis caused by Rhizopus arrhizus with combined and sequential antifungal therapy, surgery and hyperbaric therapy

We present a case of rhino-orbitary mucormycosis which progressed despite liposomal amphotericin and early surgical debridement. Combined echinocandin and high dose liposomal amphotericin, repeated debridement, prolonged therapy with hyperbaric oxygen and continued therapy with posaconazole, along with strict diabetic control, allowed cure without disfigurement.

Disseminated mucormycosis in an adolescent with newly diagnosed diabetes mellitus

We report a 16-year-old, previously healthy female who presented with disseminated mucormycosis leading to multiorgan failure and death with newly diagnosed type 1 diabetes mellitus and ketoacidosis. We review previous reported cases of mucormycosis in children with diabetes to demonstrate that this uncommon invasive infection may cause significant morbidity and mortality in this population.

Multifocal Rhizopus microsporus lung infection following brush clearing

We report a case of pulmonary Rhizopus microsporus infection in a patient with untreated diabetes following brush clearing. The patient was successfully treated with a combined medical and surgical approach with complete resolution of the lung lesions and remains asymptomatic at 11-month follow-up.

Invasive Gastric Mucormycosis-a Case Report

Mucormycosis is an opportunistic fungal infection that is associated with high mortality in immunocompromised individuals. While rhinocerebral and pulmonary forms are most common, primary gastrointestinal mucormycosis is very uncommon. The stomach is the most commonly affected organ followed by the colon and ileum in alimentary zygomycosis. We report a rare case of invasive gastric mucormycosis in a 50-year-old diabetic gentleman with a history of chronic alcoholism presenting with complaints of pain and distension of the abdomen for 6 days associated with fever, nausea, vomiting and anorexia. At presentation, he was hemodynamically unstable, febrile with uncontrolled blood sugar level and had negative HIV serology. There was generalized guarding, rigidity and distension of the abdomen and investigations confirmed perforative peritonitis. Upon exploration, there was solitary large 4 × 4 cm size perforated ulcer in the gastric body with greenish, greyish sloughed out mucosa within. Wedge resection of the ulcer with primary closure was performed. Histopathology revealed aseptate, broad, obtuse angled fungal hyphae, and invasive mucormycosis was confirmed by special stains like Periodic acid-Schiff (PAS) and Gomori's methenamine silver (GMS). Very few cases of invasive gastric mucormycosis associated with uncontrolled diabetes and alcoholism have been reported in the literature. Delayed presentation of the patient along with rapid progression to fungal septicaemia resulted in the case fatality despite early surgical intervention and critical care management.

Clinical challenge: fatal mucormycotic osteomyelitis caused by Rhizopus microsporus despite aggressive multimodal treatment

BACKGROUND

Mucormycosis is an invasive mycotic disease caused by fungi in the zygomycetes class. Although ubiquitous in the environment, zygomycetes are rarely known to cause invasive disease in immunocompromised hosts with a high mortality even under aggressive antifungal and surgical therapy. Clinically, mucormycosis frequently affects the sinus occasionally showing pulmonary or cerebral involvement. However skeletal manifestation with Rhizopus microsporus (RM) osteomyelitis leading to emergency surgical proximal femoral resection with fatal outcome has not been described yet.

CASE PRESENTATION

We report the case of a 73-year-old male suffering from myelodysplastic syndrome with precedent bone marrow transplantation. Six months after transplantation he consulted our internal medicine department in a septic condition with a four week history of painful swelling of the right hip. Radiography, computed tomography and magnetic resonance imaging revealed multiple bone infarcts in both femurs. In the right femoral head, neck and trochanteric region a recent infarct showed massive secondary osteomyelitis, breaking through the medial cortex. Emergency surgical proximal femoral resection was performed due to extensive bone and soft tissue destruction. Microbiological and basic local alignment search tool (BLAST) analysis revealed RM. Amphotericin B and posaconazole treatment with septic revision surgery was performed. However the disease ran a rapid course and was fatal two months after hospital admission.

CONCLUSION

This alarming result with extensive RM osteomyelitis in the proximal femur of an immunocompromised patient may hopefully warn medical staff to perform early imaging and aggressive surgical supported multimodal treatment in similar cases.

Mucormycoses caused by Lichtheimia species

Mucormycoses are life-threatening infections with fungi from the order Mucorales (Mucoromycotina). Although mucormycoses are uncommon compared to other fungal infections, e.g. aspergillosis and candidiasis, the number of cases is increasing especially in immunocompromised patients. Lichtheimia (formerly Absidia) species represent the second to third most common cause of mucormycoses in Europe. This mini review presents current knowledge about taxonomy and clinical relevance of Lichtheimia species. In addition, clinical presentation and risk factors will be discussed. Proper animal infection models are essential for the understanding of the pathogenesis and the identification of virulence factors of fungal pathogens. To date, several animal models have been used to study Lichtheimia infection. A brief overview of the different models and the main conclusions from the infection experiments is summarised in this review.

Mucormycosis in haematological patients: case report and results of prospective study in Saint Petersburg, Russia

We prospectively observed 36 haematological patients with mucormycosis from nine hospitals of St. Petersburg during 2004-2013. The most frequent underlying diseases were acute leukaemia (64%), and main risk factors were prolonged neutropenia (92%) and lymphocytopenia (86%). In 50% of the patients, mucormycosis was diagnosed 1-65 days after invasive aspergillosis. Main clinical form of mucormycosis was pulmonary (64%), while two or more organ involvement was noted in 50% of the cases. The most frequent aetiological agents of mucormycosis were Rhizopus spp. (48%). Twelve-week survival rate was 50%. Combination therapy (echinocandins + amphotericin B forms) and recovery from the underlying disease significantly improved the survival rate.

Mucormycosis in children: a study of 22 cases in a Mexican hospital

We present a single-centre, retrospective study (1985-2012) of 22 cases of mucormycosis in children. A total of 158 mucormycosis cases were identified, of which 22 (13.96%) were children. The mean age of the children was 10.3 years (range: 6 months-18 years), and 59% of the infections occurred in males. The rhinocerebral form was the main clinical presentation (77.27%), followed by the primary cutaneous and pulmonary patterns. The major underlying predisposing factors were diabetes mellitus in 68.18% of the patients and haematologic diseases in 27.7% of the patients. The cases were diagnosed by mycological tests, with positive cultures in 95.4% of the patients. Rhizopus arrhizus was the foremost aetiologic agent in 13/22 cases (59.1%). In 21 cultures, the aetiologic agents were identified morphologically and by molecular identification. In 10 cultures, the internal transcribed spacer region of the ribosomal DNA was sequenced. Clinical cure and mycological cure were achieved in 27.3% cases, which were managed with amphotericin B deoxycholate and by treatment of the underlying conditions.

Pathogenesis and host defence against Mucorales: the role of cytokines and interaction with antifungal drugs

Innate immune response, including macrophages, neutrophils and dendritic cells and their respective receptors, plays an important role in host defences against Mucorales with differential activity against specific fungal species, while adaptive immunity is not the first line of defence. A number of endogenous and exogenous factors, such as cytokines and growth factors as well as certain antifungal agents have been found that they influence innate immune response to these organisms. Used alone or especially in combination have been shown to exert antifungal effects against Mucorales species. These findings suggest novel ways of adjunctive therapy for patients with invasive mucormycosis.

[Disseminated mucormycosis in immunocompetent patients: A disease that also exists]

Mucormycosis is usually an acute angioinvasive infections, which leads to non-suppurative necrosis and significant tissue damage. It represents 1.6% of all the invasive fungal infections and predominates in immunosuppressed patients with risk factors. Incidence has been significantly increased even in immunocompetent patients. Due to finding a case of disseminated mucormycosis caused by Rhizomucor pusillus in a young immunocompetent patient, a systematic review was carried out of reported cases in PubMed of mucormycosis in immunocompetent adults according to the main anatomic locations, and especially in disseminated cases. A review of the main risk factors and pathogenicity, clinical manifestations, techniques of early diagnosis, current treatment options, and prognosis is presented. Taxonomy and classification of the genus Mucor has also been reviewed.

Clinical features and outcome of mucormycosis

Mucormycosis (MCM) is a life-threatening infection that carries high mortality rates despite recent advances in its diagnosis and treatment. The objective was to report 14 cases of mucormycosis infection and review the relevant literature. We retrospectively analyzed the demographic and clinical data of 14 consecutive patients that presented with MCM in a tertiary-care teaching hospital in northern Mexico. The mean age of the patients was 39.9 (range 5-65). Nine of the patients were male. Ten patients had diabetes mellitus as the underlying disease, and 6 patients had a hematological malignancy (acute leukemia). Of the diabetic patients, 3 had chronic renal failure and 4 presented with diabetic ketoacidosis. All patients had rhinocerebral involvement. In-hospital mortality was 50%. All patients received medical therapy with polyene antifungals and 11 patients underwent surgical therapy. Survivors were significantly younger and less likely to have diabetes than nonsurvivors, and had higher levels of serum albumin on admission. The clinical outcome of patients with MCM is poor. Uncontrolled diabetes and age are negative prognostic factors.

Disseminated mucormycosis in a paediatric patient: Lichthemia corymbifera successfully treated with combination antifungal therapy

Mucormycosis is a severe fungal infection that largely affects immunocompromised individuals. It carries a high morbidity and mortality rate and is characterised by extensive angioinvasion and necrosis of host tissue. This case report details success in treating disseminated mucormycosis in a paediatric patient with an underlying haematological malignancy. Treatment included institution of combination antifungal therapy with liposomal amphotericin B and caspofungin, aggressive surgical debridement of infected tissue and reversal of underlying immunosuppression.

Looks like a stroke, acts like a stroke, but it's more than a stroke: a case of cerebral mucormycosis

Mucormycosis is a fungus that exhibits angiocentric growth and can cause a thrombotic arteritis. Infection with this organism is uncommon and cerebral involvement is most often secondary to direct invasion through the paranasal sinuses. Here, we present a case of mucormycosis with cerebral involvement without sinus disease, which resulted in ischemic stroke with rapid progression resulting in death.

Mucor irregularis-associated cutaneous mucormycosis: Case report and review

Solid organ transplant recipients are at risk for invasive fungal diseases, and are also exposed to healthcare-associated mucormycosis. Mainly causing localized cutaneous mucormycosis, Mucor irregularis infection is reported for the first time in a kidney-transplant recipient. A healthcare-associated origin was highly suspected in this case. We performed a literature review and highlight the characteristics of this very rare fungus.

Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections: 2014 Update by the Infectious Diseases Society of America

A panel of national experts was convened by the Infectious Diseases Society of America (IDSA) to update the 2005 guidelines for the treatment of skin and soft tissue infections (SSTIs). The panel's recommendations were developed to be concordant with the recently published IDSA guidelines for the treatment of methicillin-resistant Staphylococcus aureus infections. The focus of this guideline is the diagnosis and appropriate treatment of diverse SSTIs ranging from minor superficial infections to life-threatening infections such as necrotizing fasciitis. In addition, because of an increasing number of immunocompromised hosts worldwide, the guideline addresses the wide array of SSTIs that occur in this population. These guidelines emphasize the importance of clinical skills in promptly diagnosing SSTIs, identifying the pathogen, and administering effective treatments in a timely fashion.

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.

Analysis of a food-borne fungal pathogen outbreak: virulence and genome of a Mucor circinelloides isolate from yogurt

Food-borne pathogens are ongoing problems, and new pathogens are emerging. The impact of fungi, however, is largely underestimated. Recently, commercial yogurts contaminated with Mucor circinelloides were sold, and >200 consumers became ill with nausea, vomiting, and diarrhea. Mucoralean fungi cause the fatal fungal infection mucormycosis, whose incidence has been continuously increasing. In this study, we isolated an M. circinelloides strain from a yogurt container, and multilocus sequence typing identified the strain as Mucor circinelloides f. circinelloides. M. circinelloides f. circinelloides is the most virulent M. circinelloides subspecies and is commonly associated with human infections, whereas M. circinelloides f. lusitanicus and M. circinelloides f. griseocyanus are less common causes of infection. Whole-genome analysis of the yogurt isolate confirmed it as being close to the M. circinelloides f. circinelloides subgroup, with a higher percentage of divergence with the M. circinelloides f. lusitanicus subgroup. In mating assays, the yogurt isolate formed sexual zygospores with the (−) M. circinelloides f. circinelloides tester strain, which is congruent with its sex locus encoding SexP, the (+) mating type sex determinant. The yogurt isolate was virulent in murine and wax moth larva host systems. In a murine gastromucormycosis model, Mucor was recovered from fecal samples of infected mice for up to 10 days, indicating that Mucor can survive transit through the GI tract. In interactions with human immune cells, M. circinelloides f. lusitanicus induced proinflammatory cytokines but M. circinelloides f. circinelloides did not, which may explain the different levels of virulence in mammalian hosts. This study demonstrates that M. circinelloides can spoil food products and cause gastrointestinal illness in consumers and may pose a particular risk to immunocompromised patients.

The U.S. FDA reported that yogurt products were contaminated with M. circinelloides, a mucoralean fungal pathogen, and >200 consumers complained of symptoms, including vomiting, nausea, and diarrhea. The manufacturer voluntarily withdrew the affected yogurt products from the market. Compared to other food-borne pathogens, including bacteria, viruses, and parasites, less focus has been placed on the risk of fungal pathogens. This study evaluates the potential risk from the food-borne fungal pathogen M. circinelloides that was isolated from the contaminated commercial yogurt. We successfully cultured an M. circinelloides isolate and found that the isolate belongs to the species M. circinelloides f. circinelloides, which is often associated with human infections. In murine and insect host models, the isolate was virulent. While information disseminated in the popular press would suggest this fungal contaminant poses little or no risk to consumers, our results show instead that it is capable of causing significant infections in animals.

Platelet immunology in fungal infections

Up to date, perception of platelets has changed from key players in coagulation to multitaskers within the immune network, connecting its most diverse elements and crucially shaping their interplay with invading pathogens such as fungi. In addition, antimicrobial effector molecules and mechanisms in platelets enable a direct inhibitory effect on fungi, thus completing their immune capacity. To precisely assess the impact of platelets on the course of invasive fungal infections is complicated by some critical parameters. First, there is a fragile balance between protective antimicrobial effects and detrimental reactions that aggravate the fungal pathogenesis. Second, some platelet effects are exerted indirectly by other immune mediators and are thus difficult to quantify. Third, drugs such as antimycotics, antibiotics, or cytostatics, are commonly administered to the patients and might modulate the interplay between platelets and fungi. Our article highlights selected aspects of the complex interactions between platelets and fungi and the relevance of these processes for the pathogenesis of fungal infections.

Potential role of 18F-FDG PET/CT in patients with fungal infections

OBJECTIVE

Combined anatomic and functional imaging with (18)F-FDG PET/CT is slowly gaining foothold in the management of various infective pathologic abnormalities. However, limited literature is available regarding the role of FDG PET/CT in patients with fungal infections.

CONCLUSION

Here, we briefly review the available literature and highlight the potential role that FDG PET/CT can play in the diagnosis and management of fungal infections.

[Invasive fungal disease due to Scedosporium, Fusarium and mucorales]

The number of emerging organisms causing invasive fungal infections has increased in the last decades. These etiological agents include Scedosporium, Fusarium and mucorales. All of them can cause disseminated, virulent, and difficult-to treat infections in immunosuppressed patients, the most affected, due to their resistance to most available antifungal agents. Current trends in transplantation including the use of new immunosuppressive treatments, the common prescription of antifungal agents for prophylaxis, and new ecological niches could explain the emergence of these fungal pathogens. These pathogens can also affect immunocompetent individuals, especially after natural disasters (earthquakes, floods, tsunamis), combat wounds or near drowning. All the invasive infections caused by Scedosporium, Fusarium, and mucorales are potentially lethal and a favourable outcome is associated with rapid diagnosis by direct microscopic examination of the involved tissue, wide debridement of infected material, early use of antifungal agents including combination therapy, and an improvement in host defenses, especially neutropenia.

Successful treatment of invasive gastric mucormycosis in a patient with alcoholic liver cirrhosis: A case report

Gastrointestinal (GI) mucormycosis is a rare and life-threatening invasive fungal infection. GI mucormycosis occur in all parts of the alimentary tract, with the stomach being the most common site. Diabetes mellitus and other types of conditions associated with immunodeficiency, including hematologic malignancies, solid organ transplantation and glucocorticoid therapy, are risk factors for GI mucormycosis. There are few studies reporting cases of gastric mucormycosis in patients with liver cirrhosis, and even fewer reporting the successful treatment of invasive gastric mucormycosis in a patient with liver cirrhosis. This study presents a case of invasive gastric mucormycosis in a patient with liver cirrhosis, which was treated successfully by prompt diagnosis, metabolic support, surgical debridement of involved tissues and antifungal therapy.

Multimodal surgical and medical treatment for extensive rhinocerebral mucormycosis in an elderly diabetic patient: a case report and literature review

Diabetes is a well-known risk factor for invasive mucormycosis with rhinocerebral involvement. Acute necrosis of the maxilla is seldom seen and extensive facial bone involvement is rare in patients with rhino-orbital-cerebral mucormycosis. An aggressive surgical approach combined with antifungal therapy is usually necessary. In this report, we describe the successful, personalized medical and surgical management of extensive periorbital mucormycosis in an elderly diabetic, HIV-negative woman. Mono- or combination therapy with liposomal amphotericin B (L-AmB) and posaconazole (PSO) and withheld debridement is discussed. The role of aesthetic plastic surgery to preserve the patient's physical appearance is also reported. Any diabetic patient with sinonasal disease, regardless of their degree of metabolic control, is a candidate for prompt evaluation to rule out mucormycosis. Therapeutic and surgical strategies and adjunctive treatments are essential for successful disease management. These interventions may include combination therapy. Finally, a judicious multimodal treatment approach can improve appearance and optimize outcome in elderly patients.

Our 2014 approach to mucormycosis

Mucormycosis, previously termed as zygomycosis, is caused by fungi belonging to the order Mucorales and is a very severe disease in immunocompromised patients with an often unfavourable outcome. Given the high morbidity and mortality of mucormycosis, establishing a timely diagnosis followed by immediate treatment is of major importance. As randomised clinical trials are lacking, we present our current diagnostic and treatment pathways for mucormycosis in the immunocompromised host. Due to the difficulty to distinguish mucormycosis from other filamentous fungi, mucormycosis always has to be considered as differential diagnosis in predisposed patients. Diagnostic procedures comprise imaging, microscopy, culture and histopathology and need to be rigorously used. In patients with a high suspicion of mucormycosis, e.g. reversed halo sign on computed tomography scanning, our approach combines liposomal amphotericin B (LAmB) with surgical debridement. In light of the rapid deterioration and poor prognosis of these patients, we prefer a daily dose of LAmB of at least 5 mg kg(-1) despite nephrotoxicity. In patients with stable disease we switch to posaconazole 200 mg four times per day. In case of progression antifungal combination is an option.

Nonmolecular methods for the diagnosis of respiratory fungal infections

Diagnosis of invasive fungal pneumonias by conventional culture methods is difficult to assess and often delayed. Nonmolecular fungal markers have emerged as an important adjunctive tool to support their diagnosis in combination with other clinical, radiologic, and microbiological criteria of invasive fungal diseases. Concerns about the sensitivity and specificity of some tests in different patient populations should lead to warnings about their widespread use. None can identify the emerging and particularly deadly fungal pathogens responsible for mucormycosis. The role of nonmolecular fungal markers should be better defined in combination with other microbiological and radiologic tools in preemptive antifungal strategies.

A 29-year-old man with hospital-acquired cavitary pneumonia

Cavitary lung processes pose a formidable diagnostic challenge. Causes vary widely and include cavitary pneumonia, vasculitis and malignancy. In some cases, patient history and basic work-up may yield a diagnosis, but in others, an extensive work-up, including tissue biopsy, may be necessary to establish the cause. The authors present a case of cavitary pneumonia that complicated an open lung biopsy. It developed in the hospital and was caused by mucormycosis, a potential emerging infection causing health care-associated infections.

Biology, systematics, and clinical manifestations of Zygomycota infections

Fungi cause opportunistic, nosocomial, and community-acquired infections. Among fungal infections (mycoses) zygomycoses are exceptionally severe, with a mortality rate exceeding 50%. Immunocompromised hosts, transplant recipients, and diabetic patients with uncontrolled keto-acidosis and high iron serum levels are at risk. Zygomycota are capable of infecting hosts immune to other filamentous fungi. The infection often follows a progressive pattern, with angioinvasion and metastases. Moreover, current antifungal therapy frequently has an unfavorable outcome. Zygomycota are resistant to some of the routinely used antifungals, among them azoles (except posaconazole) and echinocandins. The typical treatment consists of surgical debridement of the infected tissues accompanied by amphotericin B administration. The latter has strong nephrotoxic side effects, which make it unsuitable for prophylaxis. Delayed administration of amphotericin and excision of mycelium-containing tissues worsens survival prognoses. More than 30 species of Zygomycota are involved in human infections, among them Mucorales is the most abundant. Prognosis and treatment suggestions differ for each species, which makes fast and reliable diagnosis essential. Serum sample PCR-based identification often gives false-negative results; culture-based identification is time-consuming and not always feasible. With the dawn of Zygomycota sequencing projects significant advancement is expected, as in the case of treatment of Ascomycota infections.