Zygomycosis in Europe: analysis of 230 cases accrued by the registry of the European Confederation of Medical Mycology (ECMM) Working Group on Zygomycosis between 2005 and 2007

Successful isavuconazole salvage therapy in a patient with invasive mucormycosis

A 45-year-old male with rhinocerebral mucormycosis (Rhizopus oryzae), refractory to liposomal amphotericin B and posaconazole, received isavuconazole salvage therapy. Initial isavuconazole plasma and tissue levels were 0.76-0.86 μg/mL and 1.09-1.38 μg/g. Plasma levels increased to 1.3-3.24 μg/mL with reduced comedication. Isavuconazole was well tolerated, and the patient has remained disease-free 24 months post-antifungal therapy.

Rhinocerebral mucormycosis in a patient with type 1 diabetes presenting as toothache: a case report from Himalayan region of India

Mucormycosis is an angioinvasive infection caused by ubiquitous filamentous fungi of the order Mucorales. It is a rapidly progressive fatal infection mostly reported in susceptible individuals, such as those with poorly controlled diabetes or those with defects in phagocytic function. Rhinocerebral mucormycosis is the most common type of mucormycosis in diabetic patients. This case report describes a 17-year-old girl with type 1 diabetes mellitus presenting with rhinocerebral mucormycosis. The patient presented with a history of toothache and facial pain with oedema of left half of face, periorbital oedema and depressed conciousness. She had hyperglycaemia with diabetic ketoacidosis and rapidly developed hemiparesis progressing to quadriparesis and died within 3 days of admission. The current report emphasises the importance of having a high index of suspicion when dealing with patients with diabetes presenting with facial pain or cellulitis and prompt initiation of medical therapy along with surgical debridement for control of rhinocerebral mucormycosis.

Risk factors for mortality in patients with invasive mucormycosis

BACKGROUND

Mucormycosis is an uncommon and life-threatening fungal infection. The clinical predictors of outcome were evaluated in patients with invasive mucormycosis.

MATERIALS AND METHODS

We retrospectively reviewed histologically proven cases of invasive mucormycosis in our institution from 1996 to 2012.

RESULTS

A total of 64 patients were analyzed. The median age was 59 years (interquartile range [IQR], 50-67), and 32 patients (50%) were male. The most common underlying diseases were diabetes mellitus (67%), hematologic malignancy (22%), and solid cancer (19%). The most common infection sites were the rhino-orbito-cerebral area (56%) and the lungs (31%). The 180-day all-cause mortality was 33%. Disseminated infection was associated with increased mortality (hazard ratio [HR]: 169.74, 95% confidence interval [CI]: 6.41 to 4492.64; P = 0.002). Pulmonary infection (HR: 0.08, 95% CI: 0.01 to 0.66; P = 0.02) and complete surgical removal of infected tissue (HR: 0.12, 95% CI: 0.02 to 0.64; P = 0.01) were associated with decreased mortality.

CONCLUSIONS

These results suggest that patients with mucormycosis had a lower risk of mortality if they developed a pulmonary infection, rather than a disseminated infection and with complete debridement of infected tissue.

MALDI-TOF mass spectrometry in the clinical mycology laboratory: identification of fungi and beyond

MALDI-TOF mass spectrometry (MS) is becoming essential in most clinical microbiology laboratories throughout the world. Its successful use is mainly attributable to the low operational costs, the universality and flexibility of detection, as well as the specificity and speed of analysis. Based on characteristic protein spectra obtained from intact cells - by means of simple, rapid and reproducible preanalytical and analytical protocols - MALDI-TOF MS allows a highly discriminatory identification of yeasts and filamentous fungi starting from colonies. Whenever used early, direct identification of yeasts from positive blood cultures has the potential to greatly shorten turnaround times and to improve laboratory diagnosis of fungemia. More recently, but still at an infancy stage, MALDI-TOF MS is used to perform strain typing and to determine antifungal drug susceptibility. In this article, the authors discuss how the MALDI-TOF MS technology is destined to become a powerful tool for routine mycological diagnostics.

Treatment of invasive fungal infections in cancer patients-updated recommendations of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Oncology (DGHO)

The Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Oncology (DGHO) here presents its updated recommendations for the treatment of documented fungal infections. Invasive fungal infections are a main cause of morbidity and mortality in cancer patients undergoing intensive chemotherapy regimens. In recent years, new antifungal agents have been licensed, and agents already approved have been studied in new indications. The choice of the most appropriate antifungal treatment depends on the fungal species suspected or identified, the patient's risk factors (e.g., length and depth of neutropenia), and the expected side effects. This guideline reviews the clinical studies that served as a basis for the following recommendations. All recommendations including the levels of evidence are summarized in tables to give the reader rapid access to the information.

A mucormycosis case treated with a combination of caspofungin and amphotericin B

Mucormycosis is a rare, invasive and fatal disease that occurs mainly in diabetes mellitus patients with uncontrolled blood glucose levels or in immunocompromised patients. The mortality rate of this disease is as high as 25 to 80%, despite aggressive surgical treatment and antifungal therapy. This high mortality requires alternative treatment approaches. The accepted treatment modality of invasive mucormycosis are amphotericin B lipid formulations. Although echinocandins generally show no activity against Mucorales, it was shown that Rhizopus oryzae expressed the target enzyme for echinocandins, 1,3-beta-glucan synthase. Additionally, there are some experimental studies in a diabetic mouse model and case reports regarding the effects of caspofungin. In this report, we present a rhinocerebral mucormycosis case treated with liposomal amphotericin B and caspofungin. There was regression of the patient's clinical and radiological condition with the addition of caspofungin, but she died due to discontinuation of her treatment and reasons other than mucormycosis.

Complete remission obtained with azacitidine in a patient with concomitant therapy related myeloid neoplasm and pulmonary mucormycosis

Mucormycosis is the third cause of invasive mycosis after candidiasis and aspergillosis in AML patients, representing a poor prognostic factor associated with a high rate of fatal outcome. We report a case of a patient with AML and a concomitant pulmonary mucormycosis at diagnosis, who obtained a complete remission both of her AML and of the fungal infection. The incidence of the infection at the onset of leukemia is extremely unusual, and, to our knowledge, the sporadic cases reported in the literature are included in heterogeneous series retrospectively examined. In our case, Liposomal Amphotericin B as single agent appeared incapable of controlling the infection, so anti-infective therapy was intensified with posaconazole and simultaneously antileukemic treatment with 5-azacitidine was started, with the understanding that the only antifungal treatment would not have been able to keep the infection under control for a long time if not associated with a reversal of neutropenia related to the disease. We observed a progressive improvement of the general conditions, a healing of pneumonia and a complete remission of the leukemic disease, suggesting that a careful utilization of the new compounds available today, in terms of both antifungal and antileukemic treatment, may offer a curative chance a patient who would have otherwise been considered unfit for a potentially curative therapeutic strategy.

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.

DNA barcoding in Mucorales: an inventory of biodiversity

The order Mucorales comprises predominantly fast-growing saprotrophic fungi, some of which are used for the fermentation of foodstuffs but it also includes species known to cause infections in patients with severe immune or metabolic impairments. To inventory biodiversity in Mucorales ITS barcodes of 668 strains in 203 taxa were generated covering more than two thirds of the recognised species. Using the ITS sequences, Molecular Operational Taxonomic Units were defined by a similarity threshold of 99 %. An LSU sequence was generated for each unit as well. Analysis of the LSU sequences revealed that conventional phenotypic classifications of the Mucoraceae are highly artificial. The LSU- and ITS-based trees suggest that characters, such as rhizoids and sporangiola, traditionally used in mucoralean taxonomy are plesiomorphic traits. The ITS region turned out to be an appropriate barcoding marker in Mucorales. It could be sequenced directly in 82 % of the strains and its variability was sufficient to resolve most of the morphospecies. Molecular identification turned out to be problematic only for the species complexes of Mucor circinelloides, M. flavus, M. piriformis and Zygorhynchus moelleri. As many as 12 possibly undescribed species were detected. Intraspecific variability differed widely among mucorealean species ranging from 0 % in Backusella circina to 13.3 % in Cunninghamella echinulata. A high proportion of clinical strains was included for molecular identification. Clinical isolates of Cunninghamella elegans were identified molecularly for the first time. As a result of the phylogenetic analyses several taxonomic and nomenclatural changes became necessary. The genus Backusella was emended to include all species with transitorily recurved sporangiophores. Since this matched molecular data all Mucor species possessing this character were transferred to Backusella. The genus Zygorhynchus was shown to be polyphyletic based on ITS and LSU data. Consequently, Zygorhynchus was abandoned and all species were reclassified in Mucor. Our phylogenetic analyses showed, furthermore, that all non-thermophilic Rhizomucor species belong to Mucor. Accordingly, Rhizomucor endophyticus was transferred to Mucor and Rhizomucor chlamydosporus was synonymised with Mucor indicus. Lecto-, epi- or neotypes were designated for several taxa.

[Iron and invasive fungal infection]

Iron is an essential factor for both the growth and virulence of most of microorganisms. As a part of the innate (or nutritional) immune system, mammals have developed different mechanisms to store and transport this element in order to limit free iron bioavailability. To survive in this hostile environment, pathogenic fungi have specific uptake systems for host iron sources, one of the most important of which is based on the synthesis of siderophores-soluble, low-molecular-mass, high-affinity iron chelators. The increase in free iron that results from iron-overload conditions is a well-established risk factor for invasive fungal infection (IFI) such as mucormycosis or aspergillosis. Therefore, iron chelation may be an appealing therapeutic option for these infections. Nevertheless, deferoxamine -the first approved iron chelator- paradoxically increases the incidence of IFI, as it serves as a xeno-siderophore to Mucorales. On the contrary, the new oral iron chelators (deferiprone and deferasirox) have shown to exert a deleterious effect on fungal growth both in vitro and in animal models. The present review focuses on the role of iron metabolism in the pathogenesis of IFI and summarises the preclinical data, as well as the limited clinical experience so far, in the use of new iron chelators as treatment for mucormycosis and invasive aspergillosis.

Population-based survey of filamentous fungi and antifungal resistance in Spain (FILPOP Study)

A population-based survey was conducted to investigate the epidemiology of and antifungal resistance in Spanish clinical strains of filamentous fungi isolated from deep tissue samples, blood cultures, and respiratory samples. The study was conducted in two different periods (October 2010 and May 2011) to analyze seasonal variations. A total of 325 strains were isolated in 29 different hospitals. The average prevalence was 0.016/1,000 inhabitants [corrected]. Strains were identified by sequencing of DNA targets and susceptibility testing by the European Committee for Antimicrobial Susceptibility Testing reference procedure. The most frequently isolated genus was Aspergillus, accounting for 86.3% of the isolates, followed by Scedosporium at 4.7%; the order Mucorales at 2.5%; Penicillium at 2.2%, and Fusarium at 1.2%. The most frequent species was Aspergillus fumigatus (48.5%), followed by A. flavus (8.4%), A. terreus (8.1%), A. tubingensis (6.8%), and A. niger (6.5%). Cryptic/sibling Aspergillus species accounted for 12% of the cases. Resistance to amphotericin B was found in 10.8% of the isolates tested, while extended-spectrum triazole resistance ranged from 10 to 12.7%, depending on the azole tested. Antifungal resistance was more common among emerging species such as those of Scedosporium and Mucorales and also among cryptic species of Aspergillus, with 40% of these isolates showing resistance to all of the antifungal compounds tested. Cryptic Aspergillus species seem to be underestimated, and their correct classification could be clinically relevant. The performance of antifungal susceptibility testing of the strains implicated in deep infections and multicentric studies is recommended to evaluate the incidence of these cryptic species in other geographic areas.

Efficacy of liposomal amphotericin B and posaconazole in intratracheal models of murine mucormycosis

Mucormycosis is a life-threatening fungal infection almost uniformly affecting diabetics in ketoacidosis or other forms of acidosis and/or immunocompromised patients. Inhalation of Mucorales spores provides the most common natural route of entry into the host. In this study, we developed an intratracheal instillation model of pulmonary mucormycosis that hematogenously disseminates into other organs using diabetic ketoacidotic (DKA) or cyclophosphamide-cortisone acetate-treated mice. Various degrees of lethality were achieved for the DKA or cyclophosphamide-cortisone acetate-treated mice when infected with different clinical isolates of Mucorales. In both DKA and cyclophosphamide-cortisone acetate models, liposomal amphotericin B (LAmB) or posaconazole (POS) treatments were effective in improving survival, reducing lungs and brain fungal burdens, and histologically resolving the infection compared with placebo. These models can be used to study mechanisms of infection, develop immunotherapeutic strategies, and evaluate drug efficacies against life-threatening Mucorales infections.

Cunninghamella echinulata causing fatally invasive fungal sinusitis

We report a fatal case of invasive fungal sinusitis caused by Cunninghamella echinulata in a febrile, neutropenic 15-year-old male with relapsing acute leukemia. The isolate was recovered from a nasal biopsy from the right middle meatus, and microscopic examination of the tissue revealed angioinvasion and necrosis. Human infection caused by this organism has not been well documented; however, this report alerts us to its life-threatening potential.

Global epidemiology of cutaneous zygomycosis

The large majority of cases reported worldwide as zygomycosis are infections caused by fungi belonging to the order Mucorales. These infections are invasive, often lethal, and they primarily affect immunocompromised patients. Cutaneous zygomycosis is the third most common clinical presentation, after sinusitis and pulmonary disease. Most patients with cutaneous zygomycosis have underlying diseases, such as hematological malignancies and diabetes mellitus, or have received solid organ transplantation, but a large proportion of these patients are immunocompetent. Trauma is an important mode of acquiring the disease. The disease can be very invasive locally and penetrate from the cutaneous and subcutaneous tissues into the adjacent fat, muscle, fascia, and bone. The diagnosis of cutaneous zygomycosis is often difficult because of the nonspecific findings of the infection. The clinician must have a high degree of suspicion and use all available diagnostic tools, because early diagnosis leads to an improved outcome. The treatment of zygomycosis is multimodal and consists of surgical debridement, use of antifungal drugs, and reversal of underlying risk factors, when possible. The main antifungal drug used in the treatment of zygomycosis is amphotericin B. Posaconazole is sometimes used for salvage treatment, as continuation of treatment after initial administration of amphotericin B, or in combination. The mortality of cutaneous zygomycosis is lower in comparison with other forms of the disease, but it is still significant. When the disease is localized, mortality still ranges from 4% to 10%.

[Clinical and radiological aspects of mucormycosis]

Mucormycosis is an infection caused by filamentous fungi of the Mucorales order. The predisposing factors are mostly diabetic ketoacidosis and severe immunosuppressive conditions such as prolonged neutropenia, steroid or T-cell suppressor therapy, solid organ transplantation or allogeneic hematopoietic stem cell transplantation. Mucormycosis can also occur in immunocompetent patients, especially after trauma, burns or direct inoculation of the fungi (e.g. intravenous drug abuse). The most frequently targeted primary sites of infection are sinuses with a rapid spread to the adjacent tissues including the brain, the lower respiratory tract, the digestive tract and the skin. Mucorales are able to invade the vessels causing hematogenous dissemination, vascular thrombosis and, ultimately, necrosis of the lesions. Clinical and radiological aspects are similar to those observed in other invasive filamentous fungi infections such as invasive aspergillosis, fusariosis or scedosporiosis. CT-scan or MRI are mandatory to assess the extension of the lesions. The diagnosis remains difficult and is often delayed resulting in a poor outcome.

The family structure of the Mucorales: a synoptic revision based on comprehensive multigene-genealogies

The Mucorales (Mucoromycotina) are one of the most ancient groups of fungi comprising ubiquitous, mostly saprotrophic organisms. The first comprehensive molecular studies 11 yr ago revealed the traditional classification scheme, mainly based on morphology, as highly artificial. Since then only single clades have been investigated in detail but a robust classification of the higher levels based on DNA data has not been published yet. Therefore we provide a classification based on a phylogenetic analysis of four molecular markers including the large and the small subunit of the ribosomal DNA, the partial actin gene and the partial gene for the translation elongation factor 1-alpha. The dataset comprises 201 isolates in 103 species and represents about one half of the currently accepted species in this order. Previous family concepts are reviewed and the family structure inferred from the multilocus phylogeny is introduced and discussed. Main differences between the current classification and preceding concepts affects the existing families Lichtheimiaceae and Cunninghamellaceae, as well as the genera Backusella and Lentamyces which recently obtained the status of families along with the Rhizopodaceae comprising Rhizopus, Sporodiniella and Syzygites. Compensatory base change analyses in the Lichtheimiaceae confirmed the lower level classification of Lichtheimia and Rhizomucor while genera such as Circinella or Syncephalastrum completely lacked compensatory base changes.

Taxonomy and epidemiology of Mucor irregularis, agent of chronic cutaneous mucormycosis

Mucormycosis usually presents as a progressive infection with significant angio-invasion. Mucormycosis due to Mucor irregularis (formerly Rhizomucor variabilis var. variabilis), however, is exceptional in causing chronic cutaneous infection in immunocompetent humans, ultimately leading to severe morbidity if left untreated. More than 90 % of the cases known to date were reported from Asia, mainly from China. The nearest neighbour of M. irregularis is the saprobic species M. hiemalis. The aim of this study was to evaluate the taxonomic position, epidemiology, and intra- and inter-species diversity of M. irregularis based on 21 strains (clinical n = 17) by multilocus analysis using ITS, LSU, RPB1 and RPB2 genes, compared to results of cluster analysis with amplified fragment length polymorphism (AFLP) data. By combining MLST and AFLP analyses, M. irregularis was found to be monophyletic with high bootstrap support, and consisted of five subgroups, which were not concordant in all partitions. It was thus confirmed that M. irregularis is a single species at 96.1–100 % ITS similarity and low recombination rates between populations. Some geographic structuring was noted with some localised populations, which may be explained by limited air-dispersal. The natural habitat of the species is likely to be in soil and decomposing plant material.

Quantitative polymerase chain reaction detection of circulating DNA in serum for early diagnosis of mucormycosis in immunocompromised patients

BACKGROUND

The aim of our study was to assess the detection of circulating DNA from the most common species of Mucorales for early diagnosis of mucormycosis in at-risk patients.

METHODS

We retrospectively evaluated a combination of 3 quantitative polymerase chain reaction (qPCR) assays using hydrolysis probes targeting Mucor/Rhizopus, Lichtheimia (formerly Absidia), and Rhizomucor for circulating Mucorales detection. Serial serum samples from 10 patients diagnosed with proven mucormycosis (2-9 samples per patient) were analyzed.

RESULTS

No cross-reactivity was detected in the 3 qPCR assays using 19 reference strains of opportunistic fungi, and the limit of detection ranged from 3.7 to 15 femtograms/10 µL, depending on the species. DNA from Mucorales was detected in the serum of 9 of 10 patients between 68 and 3 days before mucormycosis diagnosis was confirmed by histopathological examination and/or positive culture. All the qPCR results were concordant with culture and/or PCR-based identification of the causing agents in tissue (Lichtheimia species, Rhizomucor species, and Mucor/Rhizopus species in 4, 3, and 2 patients, respectively). Quantitative PCR was negative in only 1 patient with proven disseminated mucormycosis caused by Lichtheimia species.

CONCLUSION

Our study suggests that using specific qPCR targeting several species of Mucorales according to local ecology to screen at-risk patients could be useful in a clinical setting. The cost and efficacy of this strategy should be evaluated. However, given the human and economic cost of mucormycosis and the need for rapid diagnosis to initiate prompt directed antifungal therapy, this strategy could be highly attractive.

Liposomal amphotericin B and surgery as successful therapy for pulmonary Lichtheimia corymbifera zygomycosis in a pediatric patient with acute promyelocytic leukemia on antifungal prophylaxis with posaconazole

Pulmonary zygomycosis, also referred to as mucormycosis, is a fungal infection of lungs caused by fungi of the order Mucorales in the class of Zygomycetes. It is usually associated with high morbidity and mortality. Here, we report the case of a 14-year-old girl with pediatric acute promyelocytic leukemia (APL) on antifungal prophylaxis with posaconazole, who developed pulmonary Lichtheimia corymbifera (formerly Absidia corymbifera) zygomycosis. She was successfully treated by means of liposomal amphotericin B (L-AmB) and surgery. To our knowledge, this is the first published report on pediatric APL and pulmonary zygomycosis in the English language literature. At present, the patient is in complete remission of her APL and without any signs of recurrence of zygomycosis. This report suggests that efficient diagnostics, increased physician awareness, and reliance on adjunctive surgical therapy can result in a favorable outcome of pulmonary zygomycosis in immunocompromised children with hematological malignancies.

Wound infection caused by Lichtheimia ramosa due to a car accident

A 32-year-old immunocompetent man sustained severe traumas contaminated with organic material due to a car accident. An infection caused by Lichtheimia ramosa at the site of contamination was early diagnosed and cured by multiple surgical debridement and daily cleansing with antiseptic solution only.

Emerging invasive fungal diseases in transplantation

Invasive fungal infections continue to be a major cause of morbidity and mortality in severely immunocompromised transplant patients. Although Candida spp. and Aspergillus spp. represent the majority of identified pathogens, other fungi have become increasingly prevalent among this patient population. Diagnosis and treatment of invasive fungal infections remain a challenge in transplant medicine despite recent major advances. In this review, we will emphasize emerging topics in invasive fungal infections in transplantations that occurred in 2011-2012. The current literature was reviewed to synthesize new trends in epidemiology, recent outbreaks, clinical findings, and advances in diagnostic and therapeutic resources.

Allogeneic hematopoietic cell transplantation in patients with acute myeloid leukemia and pulmonary mucormycosis

Mucormycosis is a serious invasive fungal infection in immunocompromised patients. Patients undergoing treatment for hematologic malignancies are predominantly prone to the pulmonary manifestation of mucormycosis. Historically, allogeneic hematopoietic cell transplantation (HCT) in patients suffering from pulmonary mucormycosis (PM) was considered contraindicated owing to mortality rates up to 90%. We present 3 patients with acute myeloid leukemia and PM who were treated with radical surgical debridement combined with high-dose liposomal amphotericin B (LAB), and subsequently underwent successful allogeneic HCT. To date, all 3 patients are in complete remission and show no signs of mucormycosis. Allogeneic HCT in patients with PM seems feasible provided that the infectious focus is completely removed surgically and adequate antifungal pharmacotherapy, such as high-dose LAB or posaconazole, is established.

Infections in myelodysplastic syndromes

Myelodysplastic syndromes are associated with a risk of severe infections. While neutropenia is likely to be the main predisposing factor, several other immune defects have been reported, including impaired neutrophil function, B-, T- and NK-cell defects and the possible consequences of iron overload due to red blood cell transfusions. The advanced age of most patients, their frequent comorbidities, and the fact that drugs such as hypomethylating agents and lenalidomide, which are effective in myelodysplastic syndromes but can transiently worsen neutropenia, may increase the risk of infection and their severity in this context. The majority of infections in myelodysplastic syndromes are bacterial, while the incidence of fungal infections is not well known and viral infections seem to be rare. No prophylactic measures against infections have demonstrated efficacy in myelodysplastic syndromes. However, pending more data, we propose here some recommendations for the management of patients with myelodysplastic syndromes. In the future, an important contribution can be made by prospective trials testing the efficacy of prophylactic and therapeutic approaches to infection in these patients, especially in the context of the new drugs available for myelodysplastic syndromes.

Hyperthyroidism secondary to disseminated mucormycosis in a child with acute lymphoblastic leukemia: case report and a review of published reports

Thyroiditis due to fungal infection is an extremely rare cause of hyperthyroidism. The most common etiological factor of thyroiditis is Aspergillus. Infections due to members of the Mucorales have been an increasing clinical problem in recent years, and the prognosis in generalized infections due to those fungi is usually very poor. No hyperthyroidism in a child with thyroiditis due to mucormycosis has been reported in the literature so far. We describe a clinical course of generalized mucormycosis with thyroid involvement in a 12-year-old girl treated for acute lymphoblastic leukemia. The child underwent a hyperthyroidism connected with thyroid involvement due to a fungal process. The diagnosis was based on the clinical signs, laboratory findings and typical ultrasound scan; however, later attempt to amplify the fungi DNA from the tissue block has failed. The child died because of multiorgan failure due to general fungal infection 49 days after the invasive fungal infection was diagnosed. The generalized mucormycosis is always connected with poor prognosis and the mortality is high.

Diagnosis and treatment of mucormycosis in patients with hematological malignancies: guidelines from the 3rd European Conference on Infections in Leukemia (ECIL 3)

Mucormycosis is an emerging cause of infectious morbidity and mortality in patients with hematologic malignancies. However, there are no recommendations to guide diagnosis and management. The European Conference on Infections in Leukemia assigned experts in hematology and infectious diseases to develop evidence-based recommendations for the diagnosis and treatment of mucormycosis. The guidelines were developed using the evidence criteria set forth by the American Infectious Diseases Society and the key recommendations are summarized here. In the absence of validated biomarkers, the diagnosis of mucormycosis relies on histology and/or detection of the organism by culture from involved sites with identification of the isolate at the species level (no grading). Antifungal chemotherapy, control of the underlying predisposing condition, and surgery are the cornerstones of management (level A II). Options for first-line chemotherapy of mucormycosis include liposomal amphotericin B and amphotericin B lipid complex (level B II). Posaconazole and combination therapy of liposomal amphotericin B or amphotericin B lipid complex with caspofungin are the options for second line-treatment (level B II). Surgery is recommended for rhinocerebral and skin and soft tissue disease (level A II). Reversal of underlying risk factors (diabetes control, reversal of neutropenia, discontinuation/taper of glucocorticosteroids, reduction of immunosuppressants, discontinuation of deferroxamine) is important in the treatment of mucormycosis (level A II). The duration of antifungal chemotherapy is not defined but guided by the resolution of all associated symptoms and findings (no grading). Maintenance therapy/secondary prophylaxis must be considered in persistently immunocompromised patients (no grading).

Development of a single tube multiplex real-time PCR to detect the most clinically relevant Mucormycetes species

Mucormycetes infections are very difficult to treat and a delay in diagnosis could be fatal for the outcome of the patient. A molecular diagnostic technique based on Real Time PCR was developed for the simultaneous detection of Rhizopus oryzae, Rhizopus microsporus and the genus Mucor spp. in both culture and clinical samples. The methodology used was Molecular beacon species-specific probes with an internal control. This multiplex real-time PCR (MRT-PCR) was tested in 22 cultured strains and 12 clinical samples from patients suffering from a proven mucormycosis. Results showed 100% specificity and a detection limit of 1 fg of DNA per microlitre of sample. The sensitivity was 100% for clinical cultured strains and for clinical samples containing species detected by the PCR assay. Other mucormycetes species were not detected in clinical samples. This technique can be useful for clinical diagnosis and further studies are warranted.

Mucormycosis treated with posaconazole: review of 96 case reports

Mucormycosis is an emerging invasive fungal infection, primarily affecting immunocompromised patients. The disease is difficult to diagnose and mortality reaches 40% even if treated adequately. Depending on site of infection and risk factors, surgical debridement in combination with systemically active antifungal drugs are the mainstay treatment strategies. Lipid-based amphotericin B is the treatment of choice for first-line therapy while posaconazole may be a promising alternative. We performed a PubMed search on reports of patients with mucormycosis treated with posaconazole. From 2003 to 2011, 96 cases have been published. Diagnosis was based on histology alone in 2 (2.1%) and microbiological evidence in 67 (69.8%), while no data on the diagnostic approach was reported in 27 (28.1%) patients. The most frequent pathogens were Rhizopus spp. (31.2%), followed by Mucor spp. (14.6%). The site of infection was predominantly rhino-orbital (38.5%, of which 43% also had central nervous system [CNS] involvement), followed by disseminated disease (22.1%). A complete response was achieved in 62 (64.6%), partial response in 7 (7.3%) patients, and stable disease in 1 (1%). Overall mortality was 24% (lacking data for three patients). In published case reports on posaconazole treatment for mucormycosis, the drug was frequently and successfully used in combination or as second line therapy.

Lichtheimia species exhibit differences in virulence potential

Although the number of mucormycosis cases has increased during the last decades, little is known about the pathogenic potential of most mucoralean fungi. Lichtheimia species represent the second and third most common cause of mucormycosis in Europe and worldwide, respectively. To date only three of the five species of the genus have been found to be involved in mucormycosis, namely L. corymbifera, L. ramosa and L. ornata. However, it is not clear whether the clinical situation reflects differences in virulence between the species of Lichtheimia or whether other factors are responsible. In this study the virulence of 46 strains of all five species of Lichtheimia was investigated in chicken embryos. Additionally, strains of the closest-related genus Dichotomocladium were tested. Full virulence was restricted to the clinically relevant species while all strains of L. hyalospora, L. sphaerocystis and Dichotomocladium species were attenuated. Although virulence differences were present in the clinically relevant species, no connection between origin (environmental vs clinical) or phylogenetic position within the species was observed. Physiological studies revealed no clear connection of stress resistance and carbon source utilization with the virulence of the strains. Slower growth at 37°C might explain low virulence of L. hyalospora, L. spaherocystis and Dichotomocladium; however, similarly slow growing strains of L. ornata were fully virulent. Thus, additional factors or a complex interplay of factors determines the virulence of strains. Our data suggest that the clinical situation in fact reflects different virulence potentials in the Lichtheimiaceae.

Mucormycosis after allogeneic haematopoietic stem cell transplantation: a French Multicentre Cohort Study (2003-2008)

We conducted a nationwide retrospective study to evaluate clinical characteristics and outcome of mucormycosis among allogeneic haematopoietic stem cell transplant recipients. Twenty-nine patients were diagnosed between 2003 and 2008. Mucormycosis occurred at a median of 225 days after allogeneic haematopoietic stem cell transplant, and as a breakthrough infection in 23 cases. Twenty-six patients were receiving steroids, mainly for graft-versus-host disease treatment, while ten had experienced a prior post-transplant invasive fungal infection. Twenty-six patients received an antifungal treatment; surgery was performed in 12. Overall survival was 34% at 3 months and 17% at 1 year.

Mucormycosis in organ and stem cell transplant recipients

Mucormycosis is a devastating invasive fungal disease whose incidence has increased during the past decade. Mucormycosis now represents a major threat in transplant recipients, accounting for 2% and 8% of invasive fungal infections in recent cohorts of solid-organ and allogeneic stem-cell transplant recipients, respectively. Mucormycosis most often occurs late, >3 months after transplantation, although cases occurring early have been observed, especially among liver transplant recipients and in cases of graft-transmitted infection. Recent guidelines have emphasized the direct examination of the involved fluid or tissue and culture from a sterile site as the most appropriate diagnostic strategy and the use of lipid formulations of amphotericin B and major surgery when feasible as the most appropriate first-line therapeutic strategy for mucormycosis in organ and stem cell transplant recipients.

Healthcare-associated mucormycosis

Mucormycosis is a severe emerging invasive fungal infection that occurs as a consequence of environmental exposure. We exhaustively reviewed all the cases of mucormycosis (European Organisation for Research and Treatment of Cancer/Mycoses Study Group 2008 criteria) attributed to healthcare procedures that occurred between 1970 and 2008. A total of 169 cases were studied (29% children, 61% male). Major underlying diseases were solid organ transplantation (24%), diabetes mellitus (22%), and severe prematurity (21%). Skin was the most common localization (57%), followed by gastrointestinal tract (15%). Culture results were available in 75% (92% positive), and results of histological examination were positive in 95%. Rhizopus was the most frequent genus (43%). Infection portal of entry included surgery and presence of medical devices such as catheters or adhesive tape. Outbreaks and clusters were related to adhesive bandages (19 cases), wooden tongue depressors (n = 5), ostomy bags (n = 2), water circuitry damage (n = 2), and adjacent building construction (n = 5). Thorough investigations are mandatory to identify healthcare-associated mucormycosis, notably in neonatology, hematological, and transplantation units.

Epidemiology and clinical manifestations of mucormycosis

Mucormycosis is an emerging angioinvasive infection caused by the ubiquitous filamentous fungi of the Mucorales order of the class of Zygomycetes. Mucormycosis has emerged as the third most common invasive mycosis in order of importance after candidiasis and aspergillosis in patients with hematological and allogeneic stem cell transplantation. Mucormycosis also remains a threat in patients with diabetes mellitus in the Western world. Furthermore, this disease is increasingly recognized in recently developed countries, such as India, mainly in patients with uncontrolled diabetes or trauma. Epidemiological data on this type of mycosis are scant. Therefore, our ability to determine the burden of disease is limited. Based on anatomic localization, mucormycosis can be classified as one of 6 forms: (1) rhinocerebral, (2) pulmonary, (3) cutaneous, (4) gastrointestinal, (5) disseminated, and (6) uncommon presentations. The underlying conditions can influence clinical presentation and outcome. This review describes the emerging epidemiology and the clinical manifestations of mucormycosis.

Emerging fungal infections

Trends in Medical Mycology is one of the most attractive international meetings completely dedicated to clinical and fundamental research in the field of medical mycology. It is organized by the European Confederation of Medical Mycology and the Infectious Diseases Group of the European Organization for Research and Treatment of Cancer. Approximately 1500 participants, mainly microbiologists, clinicians and basic researchers, from more than 40 countries exchanged the most important advances in mycology from basic science to clinical research. A quick focus on some relevant clinical presentations is presented here.

Risk factors for mortality in patients with mucormycosis

Optimal clinical care and clinical investigation of patients with mucormycosis are limited by absence of controlled trials, and absence of well-defined predictors of mortality or clinical response. The Deferasirox-AmBisome Therapy for mucormycosis (DEFEAT Mucor) study was the first randomized clinical trial conducted on patients with mucormycosis, and demonstrated that adjunctive deferasirox therapy did not improve outcomes of the disease. The current study describes clinical factors from the 20 patients enrolled to identify those associated with 90-day mortality of the 11 (55%) patients who died by day 90. Age, diabetes mellitus, transplant status, or antifungal therapy were not associated with mortality. However, active malignancy or neutropenia at enrollment were associated with increased mortality. Pulmonary infection was linked with lower Kaplan-Meier survival compared to non-pulmonary infection. Higher baseline serum concentrations of iron and ferritin were also associated with mortality. No patient who progressed clinically during the first 14 days of study therapy survived; however, many patients who clinically improved during that time did not survive to 90 days. In contrast, day 30 clinical response was predictive of 90-day survival. These factors may be useful in defining enrollment randomization stratification critieria for future clinical trials, and in supporting clinical care of patients with mucormycosis.