Fatal Actinomucor elegans var. kuwaitiensis infection following combat trauma

Invasive fungal infections in wars, following explosives and natural disasters: A narrative review

Infections are well-known complications in patients following traumatic injuries, frequently leading to high morbidity and mortality. In particular, trauma occurring in disaster settings, both natural and man-made, such as armed conflicts and explosives detonation, results in challenging medical conditions that impede the best management practices. The incidence of invasive fungal infections (IFI) is increasing in trauma patients who lack the typical risk factors like an immune compromised state or others. This narrative review will focus on IFI as a direct complication after natural disasters, wars, and man-made mass destruction with a summary of the available evidence about the epidemiology, clinical manifestations, risk factors, microbiology, and proper management. In this setting, the clinical manifestations of IFI may include skin and soft tissue infections, osteomyelitis, visceral infections, and pneumonia. IFI should be considered in the war inflicted patients who are exposed to unsterile environments or have wounds contaminated with soil and decaying organic matter.

Development of a monoclonal antibody and a lateral-flow device for the rapid detection of a Mucorales-specific biomarker

Mucoromycosis is a highly aggressive angio-invasive disease of humans caused by fungi in the zygomycete order, Mucorales. While Rhizopus arrhizus is the principal agent of mucoromycosis, other Mucorales fungi including Apophysomyces, Cunninghamella, Lichtheimia, Mucor, Rhizomucor and Syncephalastrum are able to cause life-threatening rhino-orbital-cerebral, pulmonary, gastro-intestinal and necrotising cutaneous infections in humans. Diagnosis of the disease currently relies on non-specific CT, lengthy and insensitive culture from invasive biopsy, and time-consuming histopathology of tissue samples. At present, there are no rapid antigen tests that detect Mucorales-specific biomarkers of infection, and which allow point-of-care diagnosis of mucoromycosis. Here, we report the development of an IgG2b monoclonal antibody (mAb), TG11, which binds to extracellular polysaccharide (EPS) antigens of between 20 kDa and 250 kDa secreted during hyphal growth of Mucorales fungi. The mAb is Mucorales-specific and does not cross-react with other yeasts and molds of clinical importance including Aspergillus, Candida, Cryptococcus, Fusarium, Lomentospora and Scedosporium species. Using the mAb, we have developed a Competitive lateral-flow device that allows rapid (30 min) detection of the EPS biomarker in human serum and bronchoalveolar lavage (BAL), with a limit of detection (LOD) in human serum of ~100 ng/mL serum (~224.7 pmol/L serum). The LFD therefore provides a potential novel opportunity for detection of mucoromycosis caused by different Mucorales species.

Combat-Related Invasive Fungal Wound Infections

INTRODUCTION

During Operation Enduring Freedom in Afghanistan, an outbreak of combat-related invasive fungal wound infections (IFIs) emerged among casualties with dismounted blast trauma and became a priority issue for the Military Health System.

METHODS

In 2011, the Trauma Infectious Disease Outcomes Study (TIDOS) team led the Department of Defense IFI outbreak investigation to describe characteristics of IFIs among combat casualties and provide recommendations related to management of the disease. To support the outbreak investigation, existing IFI definitions and classifications utilized for immunocompromised patients were modified for use in epidemiologic research in a trauma population. Following the conclusion of the outbreak investigation, multiple retrospective analyses using a population of 77 IFI patients (injured during June 2009 to August 2011) were conducted to evaluate IFI epidemiology, wound microbiology, and diagnostics to support refinement of Joint Trauma System (JTS) clinical practice guidelines. Following cessation of combat operations in Afghanistan, the TIDOS database was comprehensively reviewed to identify patients with laboratory evidence of a fungal infection and refine the IFI classification scheme to incorporate timing of laboratory fungal evidence and include categories that denote a high or low level of suspicion for IFI. The refined IFI classification scheme was utilized in a large-scale epidemiologic assessment of casualties injured over a 5.5-year period.

RESULTS

Among 720 combat casualties admitted to participating hospitals (2009-2014) who had histopathology and/or wound cultures collected, 94 (13%) met criteria for an IFI and 61 (8%) were classified as high suspicion of IFI. Risk factors for development of combat-related IFIs include sustaining a dismounted blast injury, experiencing a traumatic transfemoral amputation, and requiring resuscitation with large-volume (>20 units) blood transfusions. Moreover, TIDOS analyses demonstrated the adverse impact of IFIs on wound healing, particularly with order Mucorales. A polymerase chain reaction (PCR)-based assay to identify filamentous fungi and support earlier IFI diagnosis was also assessed using archived formalin-fixed, paraffin-embedded tissue specimens. Although the PCR-based assay had high specificity (99%), there was low sensitivity (63%); however, sensitivity improved to 83% in tissues collected from sites with angioinvasion. Data obtained from the initial IFI outbreak investigation (37 IFI patients) and subsequent TIDOS analyses (77 IFI patients) supported development and refinement of a JTS clinical practice guideline for the management of IFIs in war wounds. Furthermore, a local clinical practice guideline to screen for early tissue-based evidence of IFIs among blast casualties at the Landstuhl Regional Medical Center was critically evaluated through a TIDOS investigation, providing additional clinical practice support. Through a collaboration with the Uniformed Services University Surgical Critical Care Initiative, findings from TIDOS analyses were used to support development of a clinical decision support tool to facilitate early risk stratification.

CONCLUSIONS

Combat-related IFIs are a highly morbid complication following severe blast trauma and remain a threat for future modern warfare. Our findings have supported JTS clinical recommendations, refined IFI classification, and confirmed the utility of PCR-based assays as a complement to histopathology and/or culture to promote early diagnosis. Analyses underway or planned will add to the knowledge base of IFI epidemiology, diagnostics, prevention, and management.

Emerging mould infections: Get prepared to meet unexpected fungi in your patient

Invasive fungal diseases are increasing issues in modern medicine, where the human immunodeficiency virus (HIV) pandemic and the wider use of immunosuppressive drugs generate an ever-growing number of immunocompromised patients with an increased susceptibility to uncommon fungal pathogens. In the past decade, new species have been reported as being responsible for disseminated and invasive fungal diseases in humans. Among them, the following genera are rare but seem emerging issues: Scopulariopsis, Hormographiella, Emergomyces, Westerdykella, Trametes, Actinomucor, Saksenaea, Apophysomyces, and Rhytidhysteron. Delay in diagnosis, which is often the case in these infections, jeopardizes patients' prognosis and leads to increased mortality. Here we summarize the clinical and biological presentation and the key features to identify these emerging pathogens and we discuss the available antifungal classes to treat them. We focused on Pubmed to recover extensively reported human invasive cases and articles regarding the nine previously cited fungal organisms. Information concerning patient background, macroscopic and microscopic description and pictures of these fungal organisms, histological features in tissues, findings with commonly used antigen tests in practice, and hints on potential efficient antifungal classes were gathered. This review's purpose is to help clinical microbiologists and physicians to suspect, identify, diagnose, and treat newly encountered fungi in hospital settings.

The Antimicrobial Effectiveness and Cytotoxicity of the Antibiotic-Loaded Chitosan: ECM Scaffolds

Background: The development of multifunctional wound dressings with the ability to control hemostasis, limit infection and promote rapid wound healing and constructive tissue remodeling has been a challenge for many years. In view of these challenges, a hybrid scaffold platform was developed that combined two different extracellular matrices (ECM): ECM from decellularized mammalian tissue and ECM (chitosan) from crustaceans. Both types of ECM have well established clinical benefits that support and promote wound healing and control hemostasis. This scaffold platform could also be augmented with antibiotics to provide bactericidal activity directly to the wound site. Methods: Four different scaffold formulations were developed containing chitosan supplemented with either 20% or 50% urinary bladder matrix (UBM) hydrogel or 1% (w/v) or 10% (w/v) UBM–ECM particulates. 100% chitosan scaffolds were used as controls. The scaffolds were augmented with either minocycline or rifampicin. Escherichia Coli and Staphylococcus Aureus were used to assesses antimicrobial efficacy and duration of activity, while neutral red uptake assays were performed to establish direct and indirect cytotoxicity. Results: Results showed that scaffold handling properties, scaffold integrity over time and the efficacy and release rate of loaded antibiotics could be modified by altering scaffold composition. Moreover, antibiotics were easily released from the scaffold and could remain effective for up to 24 h by modifying the scaffold composition. Variable results with cytotoxicity testing show that further work is required to optimize the scaffold formulations but these proof of principle experiments suggest that these scaffolds have potential as bioactive wound dressings.

An Unusual Case of Actinomucor elegans: A Challenging Diagnosis

Patient: Male, 70-year-old

Final Diagnosis: Actinomucor elegans

Symptoms: Bleeding • dizziness • eschar

Medication: —

Clinical Procedure: Culture • MALDI • sequencing • tooth extraction

Specialty: Infectious Diseases

Mould Infections of Traumatic Wounds: A Brief Narrative Review

Mould infections may follow traumatic injuries, with direct fungal inoculum in the site of injury and subsequent angioinvasion, possibly resulting in tissue necrosis and systemic dissemination. The pathogenesis of mould infections following trauma injuries presents unique features compared with classical mould infections occurring in neutropenic or diabetic patients, because a large fraction of post-traumatic mould infections is observed in previously healthy individuals. Most of the published clinical experience and research on mould infections following traumatic injuries regards soldiers and infections after natural disasters. However, following trauma and soil contamination (e.g., agricultural or automotive injuries) other immunocompetent individuals may develop mould infections. In these cases, delays in correct diagnosis and treatment may occur if pertinent signs such as necrosis and absent or reduced response to antibacterial therapy are not promptly recognized. Awareness of mould infections in at-risk populations is needed to rapidly start adequate laboratory workflow and early antifungal therapy in rapidly evolving cases to improve treatment success and reduce mortality.

Invasive mucormycosis during treatment for acute lymphoblastic leukaemia-successful management of two life-threatening diseases

A 5-year-old patient treated for acute lymphoblastic leukaemia (ALL) developed proven pulmonary invasive fungal disease (IFD) due to Actinomucor elegans. While completing ALL treatment according to AIEOP ALL protocol 2009 for further 15 months, antifungal treatment with liposomal amphotericin B and intermittent additional posaconazole was continued until immune reconstitution 7 months after the end of ALL treatment. Repeated imaging guided treatment decisions. Twenty-six and 19 months after the end of ALL treatment and antifungal treatment, respectively, the patient is still in the first complete remission and shows no signs of active invasive fungal disease (IFD).

Treatment of Suspected Invasive Fungal Infection in War Wounds

Invasive fungal wound infections (IFIs) were an unexpected complication associated with blast-related wounds during Operation Enduring Freedom. Between 2010 and 2012, IFI incidence rates were as high as 10-12% for patients injured during Operation Enduring Freedom and admitted to the intensive care unit at the Landstuhl Regional Medical Center. Independent risk factors for the development of IFIs include dismounted blast injuries, above knee amputations and massive (>20 units) packed red blood cell transfusions within 24 hours after injury. The Joint Trauma System developed a Clinical Practice Guideline on IFI prevention, identification and management. Aggressive and frequent surgical debridement remains the primary therapy accompanied by topical antifungal therapy (e.g., Dakins solution). Empiric systemic antifungal therapy with both liposomal amphotericin B and an intravenous broad-spectrum triazole (e.g., voriconazole or posaconazole) should be administered when there is strong suspicion of IFI based on the occurrence of recurrent wound necrosis following serial surgical debridements, since many cases involve multiple fungal species. Other recommendations include: (1) early tissue sampling for wound histopathology and fungal cultures, (2) early consultation with infectious disease specialists, and (3) coordination with surgical pathology and clinical microbiology.

Phylogenetic Status of Two Undescribed Zygomycete Species from Korea: Actinomucor elegans and Mucor minutus

During a survey of fungal diversity of the order Mucorales, three zygomycete isolates, CNUFC-YR113-1, CNUFC-KNU16-7, and CNUFC-BS1-1 were isolated from freshwater and soil samples in Korea. The strains were analyzed both morphologically and phylogenetically based on internal transcribed spacer and 28S rDNA gene sequences. Based on their morphology and phylogeny, the CNUFC-YR113-1 and CNUFC-KNU16-7 isolates were identified as Actinomucor elegans, and CNUFC-BS1-1 was identified as Mucor minutus. To the best of our knowledge, the species A. elegans and M. minutus, belonging to an undiscovered taxon, have not been previously described in Korea.

Update on Actinomucor elegans, a mucormycete infrequently detected in human specimens: how combined microbiological tools contribute efficiently to a more accurate medical care

Actinomucor elegans is a fungus belonging to mucormycetes and is still probably underdiagnosed due to misidentification. Based on a recent first case of Actinomucor elegans sinusitis in Europe, in an immunocompromised patient under voriconazole treatment, this paper aims to summarize knowledge about A. elegans mucormycoses. Even if the diagnosis of mucormycosis was made using traditional mycology techniques, precise identification of the fungus could only be achieved using molecular tools. In this observation, the galactomannan dosage was positive until the introduction of treatment and surgical debridement. The patient experienced no relapse after one year. By reviewing the four previous A. elegans reported cases and describing the mycological characteristics of this species, we highlight the need to use a combination of tools to improve the diagnostic strategy in such rare and life-threatening clinical situations.

Cutaneous mucormycosis secondary to penetrative trauma

INTRODUCTION

Mucormycosis is a rare but serious sequelae of penetrating trauma [1-5]. In spite of aggressive management, mortality remains high due to dissemination of infection. We completed a review of literature to determine the most optimal treatment of cutaneous mucormycosis which occurs secondary to penetrating trauma.

METHODS

We completed a review regarding the management of mucormycosis in trauma patients. We selected a total of 36 reports, of which 18 were case-based, for review.

RESULTS

Surgical debridement is a primary predictor of improved outcomes in the treatment of mucormycosis [3,6,7]. Anti-fungal therapy, especially lipid soluble formulation of Amphotericin B, is helpful as an adjunct or when surgical debridement has been maximally achieved. Further research is needed to fully evaluate the impact of topical dressings; negative pressure wound therapy is helpful.

CONCLUSION

An aggressive and early surgical approach, even at the expense of disfigurement, is necessary to reduce mortality in the setting of cutaneous mucormycosis that results from penetrating trauma [4,8,9]. Anti-fungal therapy and negative pressure wound therapy are formidable adjuncts.

Traumatic andropause after combat injury

In association with lower extremity amputation, complex genitourinary injuries have emerged as a specific challenge in modern military trauma surgery. Testicular injury or loss has profound implications for the recovering serviceman, in terms of hormone production and future fertility. The initial focus of treatment for patients with traumatic testicular loss is haemostasis, resuscitation and management of concurrent life-threatening injuries. Multiple reoperations are commonly required to control infection in combat wounds; in a review of 300 major lower extremity amputations, 53% of limbs required revisional surgery, with infection the commonest indication. Atypical infections, such as invasive fungal organisms, can also complicate military wounding. We report the case of a severely wounded serviceman with complete traumatic andropause, whose symptomatic temperature swings were initially mistaken for signs of occult sepsis.

Mucormycosis: a rare fungal infection in tornado victims

This article reviews four immunocompetent patients who developed a rare fungal infection, mucormycosis, secondary to multiple traumatic injuries sustained during an EF-5 tornado in Joplin, MO. Commonly found in soil and decaying organic matter, mucorales are fungi associated with soft tissue and cutaneous infections. Onset of this fungal infection can occur without clinical signs, presenting several days to several weeks after injury, delaying diagnosis. A multidisciplinary treatment approach including aggressive antifungal therapy and aggressive surgical debridement is critical. This diagnosis should be considered in all patients presenting with injuries sustained from high-velocity embedment of debris such as natural disasters or explosions. We present four cases of mucormycosis, species Apophysomyces trapeziformis. Data reported includes predisposing factors, number of days between injury and diagnosis of mucormycosis, surgical treatment, antifungal therapy, outcomes, and potential risk factors that may have contributed to the development of mucormycosis.

Combat-Related Invasive Fungal Wound Infections

Combat-related invasive fungal (mold) wound infections (IFIs) have emerged as an important and morbid complication following explosive blast injuries among military personnel. Similar to trauma-associated IFI cases among civilian populations, as in agricultural accidents and natural disasters, these infections occur in the setting of penetrating wounds contaminated by environmental debris. Specific risk factors for combat-related IFI include dismounted (patrolling on foot) blast injuries occurring mostly in southern Afghanistan, resulting in above knee amputations requiring resuscitation with large-volume blood transfusions. Diagnosis of IFI is based upon early identification of a recurrently necrotic wound following serial debridement and tissue-based histopathology examination with special stains to detect invasive disease. Fungal culture of affected tissue also provides supportive information. Aggressive surgical debridement of affected tissue is the primary therapy. Empiric antifungal therapy should be considered when there is a strong suspicion for IFI. Both liposomal amphotericin B and voriconazole should be considered initially for treatment since many of the cases involve not only Mucorales species but also Aspergillus or Fusarium spp., with narrowing of regimen based upon clinical mycology findings.

Host-iron assimilation: pathogenesis and novel therapies of mucormycosis

Mucormycosis is a fungal infection caused by organisms belonging to the order Mucorales. Although considered uncommon, mucormycosis has been steadily increasing in incidents for the last two decades. Mortality of the disease is unacceptably high despite antifungal therapy and surgical interventions. The lack of understanding of the pathogenesis of the disease and the absence of rapid diagnostic assay contribute to the poor prognosis of mucormycosis. The hyper susceptibility of patients with elevated available serum iron points to the critical role of the ability of Mucorales to acquire host iron as a critical virulence factor. Specifically patients with deferoxamine-therapy, hyperglycaemic with or without ketoacidosis, or other forms of acidosis are uniquely predisposed to mucormycosis. In this review, we discuss the molecular mechanisms of infection in these patient categories in an attempt to identify novel therapies for a disease with poor prognosis. Emphasis on the effect of glucose and free iron on host-pathogen interactions are also covered.

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.

Invasive mold infections following combat-related injuries

BACKGROUND

Major advances in combat casualty care have led to increased survival of patients with complex extremity trauma. Invasive fungal wound infections (IFIs) are an uncommon, but increasingly recognized, complication following trauma that require greater understanding of risk factors and clinical findings to reduce morbidity.

METHODS

The patient population includes US military personnel injured during combat from June 2009 through December 2010. Case definition required wound necrosis on successive debridements with IFI evidence by histopathology and/or microbiology (Candida spp excluded). Case finding and data collected through the Trauma Infectious Disease Outcomes Study utilized trauma registry, hospital records or operative reports, and pathologist review of histopathology specimens.

RESULTS

A total of 37 cases were identified: proven (angioinvasion, n=20), probable (nonvascular tissue invasion, n=4), and possible (positive fungal culture without histopathological evidence, n=13). In the last quarter surveyed, rates reached 3.5% of trauma admissions. Common findings include blast injury (100%) during foot patrol (92%) occurring in southern Afghanistan (94%) with lower extremity amputation (80%) and large volume blood transfusion (97.2%). Mold isolates were recovered in 83% of cases (order Mucorales, n=16; Aspergillus spp, n=16; Fusarium spp, n=9), commonly with multiple mold species among infected wounds (28%). Clinical outcomes included 3 related deaths (8.1%), frequent debridements (median, 11 cases), and amputation revisions (58%).

CONCLUSIONS

IFIs are an emerging trauma-related infection leading to significant morbidity. Early identification, using common characteristics of patient injury profile and tissue-based diagnosis, should be accompanied by aggressive surgical and antifungal therapy (liposomal amphotericin B and a broad-spectrum triazole pending mycology results) among patients with suspicious wounds.

Actinomucor elegans as an emerging cause of Mucormycosis

We report an invasive mucormycosis caused by Actinomucor elegans in a patient with refractory aplastic anemia. The organism was isolated from a necrotic skin lesion on the patient's left arm and demonstrated angioinvasive features on histopathology examination. In contrast to three cases described previously, we describe the first case of A. elegans invasive fungal infection in an immunocompromised patient. This report, along with the three previously reported cases, is convincing evidence that A. elegans is an emerging fungal pathogen capable of causing invasive mucormycosis in humans.

Mucormycosis caused by unusual mucormycetes, non-Rhizopus, -Mucor, and -Lichtheimia species

Rhizopus, Mucor, and Lichtheimia (formerly Absidia) species are the most common members of the order Mucorales that cause mucormycosis, accounting for 70 to 80% of all cases. In contrast, Cunninghamella, Apophysomyces, Saksenaea, Rhizomucor, Cokeromyces, Actinomucor, and Syncephalastrum species individually are responsible for fewer than 1 to 5% of reported cases of mucormycosis. In this review, we provide an overview of the epidemiology, clinical manifestations, diagnosis of, treatment of, and prognosis for unusual Mucormycetes infections (non-Rhizopus, -Mucor, and -Lichtheimia species). The infections caused by these less frequent members of the order Mucorales frequently differ in their epidemiology, geographic distribution, and disease manifestations. Cunninghamella bertholletiae and Rhizomucor pusillus affect primarily immunocompromised hosts, mostly resulting from spore inhalation, causing pulmonary and disseminated infections with high mortality rates. R. pusillus infections are nosocomial or health care related in a large proportion of cases. While Apophysomyces elegans and Saksenaea vasiformis are occasionally responsible for infections in immunocompromised individuals, most cases are encountered in immunocompetent individuals as a result of trauma, leading to soft tissue infections with relatively low mortality rates. Increased knowledge of the epidemiology and clinical presentations of these unusual Mucormycetes infections may improve early diagnosis and treatment.