In Vitro Antifungal Susceptibility of Yeast and Mold Phases of Isolates of Dimorphic Fungal Pathogen Emergomyces africanus (Formerly Emmonsia sp.) from HIV-Infected South African Patients

Invasive fungal disease in the immunocompromised host: changing epidemiology, new antifungal therapies, and management challenges

BACKGROUND

Invasive fungal disease (IFD) causes morbidity and mortality in immunocompromised hosts (ICHs). Based on increasing recognition of the impact of IFD on human disease, a recent WHO priority list identified key areas of need.

OBJECTIVES

This review examines changes in the epidemiology of IFD, in particular the emergence of antifungal-resistant pathogens and the current availability of rapid diagnostic tests and antifungal treatment options.

SOURCES

Literature between 2000 and January 2024 regarding fungal epidemiology, diagnostic tests, antifungal resistance, emerging fungal pathogens, and novel antifungal agents in both adult and paediatric ICH were reviewed.

CONTENT

We describe the changing epidemiology and continued burden and mortality of IFD in ICH. Furthermore, we discuss the emergence of antifungal-resistant organisms driven by new immunosuppressed populations, climate change, and antifungal exposure in the individual and environment. We highlight novel antifungal agents and how they will address current unmet needs.

IMPLICATIONS

The changing epidemiology and increased population at risk for IFD, lack of recognition or quantification of risks for IFD with new therapies, current gaps in the availability of rapid diagnostic tests, and the imminent availability of novel antifungals with distinct spectra of activity argue for improved availability of and access to rapid diagnostics, antifungal stewardship programmes, and global access to antifungal agents.

Diagnosis and treatment of a patient with pulmonary infection caused by Emergomyces Orientalis: a case report

Emergomycosis is a dimorphic fungal disease that is typically disseminated and fatal among immunocompromised individuals. In the case report, we presented a patient with intermittent fever, night sweats, coughing and phlegm. Chest computed tomography revealed multiple soft-tissue nodules in both lungs. Routine pathological and microbiological tests did not confirm the diagnosis. Therefore, we conducted pathogen detection using metagenomic next-generation sequencing in bronchoalveolar lavage fluid and identified the pulmonary infection caused by Emergomyces orientalis (Es. orientalis). During the antifungal treatment, the patient experienced renal function damage, and we have attempted various antifungal drugs for treatment. Finally, the patient's condition was brought under control. Therefore, the metagenomic next-generation sequencing pathogen detection was essential.

In vitro manogepix susceptibility testing of South African Emergomyces africanus, Emergomyces pasteurianus, and Blastomyces emzantsi clinical isolates

We performed in vitro antifungal susceptibility testing of manogepix against the yeast phase of 78 Emergomyces africanus, 2 Emergomyces pasteurianus, and 5 Blastomyces emzantsi isolates using a reference broth microdilution method following Clinical and Laboratory Standards Institute recommendations. All three pathogens had low minimum inhibitory concentrations ranging from <0.0005 to 0.008 mg/L. Manogepix should be investigated in animal models and potentially in future human clinical trials for endemic mycoses.

Emergomycosis, an Emerging Thermally Dimorphic Fungal Infection: A Systematic Review

Emergomycosis is an endemic mycosis caused by the Emergomyces species. Infections due to this agent have been reported globally. Hence, the present systematic review on Emergomyces infections was conducted to study the disease epidemiology, underlying diseases and risk factors, causative agents, and treatment and outcome. The MEDLINE, Scopus, Embase, and Web of Science databases were searched systematically with appropriate keywords from January 1990 to October 2022. A total of 77 cases of emergomycosis were included in the analysis. Emergomycosis was most commonly seen in patients with human immunodeficiency virus (HIV) infection (n = 61, 79.2%) and HIV-uninfected patients with or without other comorbidities (n = 16, 20.8%). The underlying disease and risk factors significantly associated with emergomycosis in the HIV-infected patients were CD4+ T-cell counts less than 100 cells/mm3 (n = 55, 90.2%), anaemia (n = 30, 49.2%), and thrombocytopenia (n = 17, 27.9%), whereas in the HIV-uninfected patients, treatment with immunosuppressive drugs (n = 10, 62.5%), renal disease (n = 8, 50%), transplant recipients (n = 6, 37.5%), and diabetes mellitus (n = 4, 25%) were the significant risk factors associated with emergomycosis. Emergomyces africanus (n = 55, 71.4%) is the most common causative agent, followed by E. pasteurianus (n = 9, 11.7%) and E. canadensis (n = 5, 6.5%). E. africanus was most often isolated from HIV-infected patients (n = 54, 98.2%), whereas E. pasteurianus was most common in HIV-uninfected patients (n = 5, 55.6%). The all-cause mortality rate of the total cohort is 42.9%. No significant variation in the mortality rate is observed between the HIV-infected patients (n = 28, 36.4%) and the HIV-uninfected patients (n = 5, 6.5%). In conclusion, with an increase in the immunosuppressed population across the globe in addition to HIV infection, the case burden of emergomycosis may increase in the future. Hence, clinicians and mycologists should be vigilant and clinically suspicious of emergomycosis, which helps in early diagnosis and initiation of antifungal treatment to prevent disease mortality.

Emergomycosis in Africa: Time to Pay Attention to This Emerging Deadly Fungal Infection

Emergomycosis is an emerging deadly infectious disease caused primarily by a little-known airborne pathogen Emergomyces africanus, which can cause clinical management challenge especially in patients with advanced HIV disease. This minireview describes Es. africanus as the main cause of emergomycosis in Africa as well as considers contributing factors to the difficulties encountered in managing this infection. Emergomycosis is common in HIV-positive persons with low CD4 lymphocyte count and has an estimated fatality of 50%. The infection exhibits airborne transmission with pulmonary and extrapulmonary manifestations leading to skin lesions. However, the pathogenesis of Es. africanus is still poorly understood. The management of the infection is complicated due to lack of defined diagnostic and therapeutic guidelines. Limited expertise, poor research funding, and lack of awareness and national surveillance are thought to impact the recognition and prioritisation of the infection. These factors may ultimately assign emergomycosis a 'neglected infection status' even as it is suspected to be prevalent in more African countries than previously recognised. Increased awareness and integrated and targeted strategies such as mobilising manpower in clinical mycology are of paramount importance in managing emergomycosis in Africa and beyond.

Emergomyces pasteurianus in Man Returning to the United States from Liberia and Review of the Literature

A 65-year-old man with HIV sought treatment for fever, weight loss, and productive cough after returning to the United States from Liberia. Fungal cultures grew Emergomyces pasteurianus, and the patient's health improved after beginning voriconazole. We describe the clinical case and review the literature, treatment, and susceptibilities for E. pasteurianus.

Review: Emergomycosis

Purpose of Review In this review, we provide an overview of emergomycosis from a clinical perspective and discuss the taxonomy and classification of the pathogens, epidemiology, pathophysiology of infection and mechanisms of pathogenesis, immunology, clinical manifestations, laboratory culture and diagnosis, molecular characterisation, therapy and prognosis. Recent Findings While Emergomyces pasteurianus is the most geographically-widespread species, Emergomyces africanus is endemic to Southern Africa and causes disseminated disease with cutaneous involvement primarily among patients with advanced human immunodeficiency virus (HIV) disease. Summary Emergomycosis, a disseminated clinical disease resulting from infection with dimorphic fungi in the genus Emergomyces, occurs primarily among immunocompromised patients. Further knowledge is needed on the pathophysiology, diagnosis and management of emergomycosis.

Invasive Fungal Diseases in Africa: A Critical Literature Review

Invasive fungal diseases (IFDs) are of huge concern in resource-limited settings, particularly in Africa, due to the unavailability of diagnostic armamentarium for IFDs, thus making definitive diagnosis challenging. IFDs have non-specific systemic manifestations overlapping with more frequent illnesses, such as tuberculosis, HIV, and HIV-related opportunistic infections and malignancies. Consequently, IFDs are often undiagnosed or misdiagnosed. We critically reviewed the available literature on IFDs in Africa to provide a better understanding of their epidemiology, disease burden to guide future research and interventions. Cryptococcosis is the most encountered IFD in Africa, accounting for most of the HIV-related deaths in sub-Saharan Africa. Invasive aspergillosis, though somewhat underdiagnosed and/or misdiagnosed as tuberculosis, is increasingly being reported with a similar predilection towards people living with HIV. More cases of histoplasmosis are also being reported with recent epidemiological studies, particularly from Western Africa, showing high prevalence rates amongst presumptive tuberculosis patients and patients living with HIV. The burden of pneumocystis pneumonia has reduced significantly probably due to increased uptake of anti-retroviral therapy among people living with HIV both in Africa, and globally. Mucormycosis, talaromycosis, emergomycosis, blastomycosis, and coccidiomycosis have also been reported but with very few studies from the literature. The emergence of resistance to most of the available antifungal drugs in Africa is yet of huge concern as reported in other regions. IFDs in Africa is much more common than it appears and contributes significantly to morbidity and mortality. Huge investment is needed to drive awareness and fungi related research especially in diagnostics and antifungal therapy.

Endemic Mycoses: Novel Findings for the Clinician

Endemic mycoses are difficult-to-diagnose conditions that may mimic several other diseases, particularly tuberculosis, community-acquired pneumonia, and cancer [...]

A presumptive case of cutaneous emergomycosis in a female patient with HIV - Maseru, Lesotho

Emergomycosis is a recently described emerging opportunistic fungal infection among individuals living with HIV, in whom it is a cause of significant mortality and morbidity. This article retrospectively reports on a presumptive case of extensive cutaneous emergomycosis in a young immunocompromised patient from Lesotho. The histopathological features on skin biopsy were in keeping with emergomyces infection. The lesions responded to treatment with amphotericin B and oral fluconazole.

Contribution

This case contributes to the existing evidence that as an emergent opportunistic infection, emergomycosis is possibly widespread in Africa but the true extend of the disease is not fully defined. This is further aggravated by the diagnostic difficulty as a result of limited resources in some areas in the region.

Endemic mycoses in South Africa, 2010–2020: A decade-long description of laboratory-diagnosed cases and prospects for the future

Background

Emergomycosis, histoplasmosis, sporotrichosis and blastomycosis are endemic to southern Africa; the first two are AIDS-related mycoses. We described laboratory-diagnosed cases of endemic and imported mycoses in South Africa over a decade and discuss available diagnostic tools, reasons for the current under-estimation of cases and future strategies to improve case ascertainment.

Materials and methods

We analysed electronic pathology laboratory data from all public laboratories and one large private laboratory in South Africa from 2010–2020. Diagnostic specimens processed at the national mycology reference laboratory were also included. We classified cases as proven, probable and possible based on the method of identification.

Results

We identified 682 cases, of which 307 were proven, 279 were probable and 96 were possible. Of 307 culture-confirmed cases, 168 were identified by phenotypic methods plus sequencing, 128 by phenotypic methods alone and 11 by direct PCR. Of 279 probable cases, 176 had yeasts observed on histology, 100 had a positive Histoplasma antigen test and 3 a positive pan-dimorphic PCR test. All 96 possible cases had compatible clinical syndrome with inflammatory infiltrates on skin tissue histology. A majority of cases had an unspecified endemic mycosis (207/682, 30.4%), followed by sporotrichosis (170/682, 24.9%), emergomycosis (154/682, 22.6%), histoplasmosis (133/682, 19.5%), blastomycosis (14/682, 2.1%) and talaromycosis (4/682, 0.6%).

Conclusions

This study reports a relatively low number of cases over a decade considering an estimated large population at risk, suggesting that a substantial fraction of cases may remain undiagnosed. There is a need to increase awareness among healthcare workers and to develop rapid point-of-care diagnostic tools and make these widely accessible.

Emergomycosis, histoplasmosis, sporotrichosis and blastomycosis are serious fungal diseases which occur in southern Africa among people with either healthy or weakened immune systems. These fungal diseases may be missed because they mimic other diseases, occur together with other conditions that mask their presence or are simply not considered by healthcare workers. There are very few available simple diagnostic tests and most African countries do not conduct fungal disease surveillance. We described cases of these fungal diseases, which had been diagnosed in South African laboratories, from 2010–2020. We identified 682 cases, of which 307 were proven, 279 were probable and 96 were possible based on the available clinical and laboratory information. A majority of cases could not be allocated to one of the four disease types and were classified as unspecific endemic mycoses (30.4%). The remainder were sporotrichosis (24.9%), emergomycosis (22.3%), histoplasmosis (19.5%), blastomycosis (2.1%) and a travel-associated infection, talaromycosis (0.6%). We found relatively few cases considering the large population at risk. We believe that this could be due to the above-mentioned issues and insufficient expertise in diagnostic laboratories. There is a need to increase awareness among healthcare workers and to develop rapid point-of-care diagnostic tools and make these widely accessible.

Isolated Pulmonary Emergomycosis in an Immunocompetent Patient in Alberta, Canada

Emergomyces canadensis pulmonary infection was incidentally diagnosed in an asymptomatic patient suspected to have metastatic osteosarcoma. Molecular diagnosis was imperative to fungal identification given overlapping histopathological features with histoplasmosis. This report documents a case of isolated pulmonary emergomycosis in an otherwise immunocompetent patient while discussing diagnostic and management pitfalls of this emerging and underdiagnosed infection.

Emerging Fungal Infections

Various uncommon fungal pathogens have been increasingly identified as causes of disseminated and invasive fungal disease (IFD) worldwide. Growing recognition and clinical knowledge of these emerging fungal pathogens has occurred through improved molecular diagnostics, nucleic sequence databases, and taxonomic reclassification of medically significant fungi. However, emerging fungal diseases carry significant morbidity and mortality and, due to a paucity of published literature, the collective clinical experience with these fungi is often limited. In this review, we focus on unusual emerging fungal pathogens not extensively covered elsewhere in this issue of Infectious Diseases Clinics of North America.

Deep fungal infections diagnosed by histology in Uganda: a 70-year retrospective study

Fungal infections cause substantial morbidity and mortality. However, the burden of deep fungal infections is not well described in Uganda. We aimed to estimate the burden and etiology of histologically diagnosed deep fungal infections in Uganda. We retrospectively reviewed histology reports at the Pathology Reference Laboratory, Department of Pathology, Makerere University, Kampala, Uganda from January 1950 to September 2019 to identify any reports that had a fungal infection as the diagnosis. Over the study period, 697 cases of deep fungal infections were identified with an average incidence of 0.73/100,000 persons per decade. There was a general decline in the number of cases detected. Median age of the cases was 28 years (IQR: 11-40) and majority (59%) were male. The age group of 0-10 years were the most affected. The foot was the most affected part of the body (26%). Deep mycoses identified include eumycetoma (32%), subcutaneous phycomycosis (26%), histoplasmosis (9.2%), chromoblastomycosis (4.6%), aspergillosis (3.3%), cryptococcosis (3.3%), blastomycosis (1.6%), subcutaneous mycosis (1.4%), dermatomycosis (1.3%), coccidioidomycosis (0.6%), mucormycosis (0.6%), and sporotrichosis (0.1%). Histoplasma was the commonest causative agent (9.2%) followed by Aspergillus (3.4%) and Cryptococcus (3.3%), while 81% of the fungal pathogens were not identified to genus/species level. Only 31% of the cases were diagnosed clinically as deep fungal infections. There is a substantial burden of deep fungal infections caused by multiple fungal pathogens in Uganda. There is need to build local capacity for mycology so as to improve on the index of clinical suspicion and diagnostic capabilities.

Emergomycosis, an Emerging Systemic Mycosis in Immunocompromised Patients: Current Trends and Future Prospects

Recently, the global emergence of emergomycosis, a systemic fungal infection caused by a novel dimorphic fungus Emergomyces species has been observed among immunocompromised individuals. Though initially classified under the genus Emmonsia, a taxonomic revision in 2017 based on DNA sequence analyses placed five Emmonsia-like fungi under a separate genus Emergomyces. These include Emergomyces pasteurianus, Emergomyces africanus, Emergomyces canadensis, Emergomyces orientalis, and Emergomyces europaeus. Emmonsia parva was renamed as Blastomyces parvus, while Emmonsia crescens and Emmonsia sola remained within the genus Emmonsia until a taxonomic revision in 2020 placed both the species under the genus Emergomyces. However, unlike other members of the genus, Emergomyces crescens and Emergomyces sola do not cause disseminated disease. The former causes adiaspiromycosis, a granulomatous pulmonary disease, while the latter has not been associated with human disease. So far, emergomycosis has been mapped across four continents: Asia, Europe, Africa and North America. However, considering the increasing prevalence of HIV/AIDS, it is presumed that the disease must have a worldwide distribution with many cases going undetected. Diagnosis of emergomycosis remains challenging. It should be considered in the differential diagnosis of histoplasmosis as there is considerable clinical and histopathological overlap between the two entities. Sequencing the internal transcribed spacer region of ribosomal DNA is considered as the gold standard for identification, but its application is compromised in resource limited settings. Serological tests are non-specific and demonstrate cross-reactivity with Histoplasma galactomannan antigen. Therefore, an affordable, accessible, and reliable diagnostic test is the need of the hour to enable its diagnosis in endemic regions and also for epidemiological surveillance. Currently, there are no consensus guidelines for the treatment of emergomycosis. The recommended regimen consists of amphotericin B (deoxycholate or liposomal formulation) for 1–2 weeks, followed by oral itraconazole for at least 12 months. This review elaborates the taxonomic, clinical, diagnostic, and therapeutic aspects of emergomycosis. It also enumerates several novel antifungal drugs which might hold promise in the treatment of this condition and therefore, can be potential areas of future studies.

Cross-reactivity of a Histoplasma capsulatum antigen enzyme immunoassay in urine specimens from persons with emergomycosis in South Africa

Histoplasma antigen detection in urine is a rapid diagnostic method for disseminated histoplasmosis, although cross-reactivity has been reported in specimens from patients with other thermally dimorphic fungal infections. We tested urine specimens, from persons with suspected invasive fungal infections, using a commercial monoclonal antibody Histoplasma enzyme immunoassay (EIA) at a South African national mycology reference laboratory from August 2014 through December 2018. Corresponding fungal culture and histopathology results were obtained from an electronic laboratory information system. In some cases, cultured fungal isolates were sent with the urine specimen for species-level identification by phenotypic and molecular methods. Cross-reactivity was confirmed using culture filtrates of several fungal pathogens. Of 212 referred cases, 41 (19%) were excluded since they had no recorded clinical history (n = 1), alternative diagnoses were confirmed (n = 2), or no fungal culture or histopathology results (n = 38). Eighty-seven of 212 (41%) had laboratory evidence of an invasive fungal disease, while 84 (40%) did not. Of the 87 cases, 37 (43%) were culture-confirmed mycoses: emergomycosis (n = 18), histoplasmosis (n = 8), sporotrichosis (n = 6), cryptococcosis (n = 2), talaromycosis (n = 1), and other fungi isolated (n = 2). The sensitivity and specificity of the EIA were calculated for two groups: culture-confirmed (n = 37) and histology-confirmed invasive fungal disease (n = 50). The sensitivity and specificity of the EIA for diagnosis of histoplasmosis compared to culture were 88% (7/8, 95%CI 47-100%) and 72% (21/29, 95%CI 53-87%), respectively, and for diagnosis of emergomycosis/histoplasmosis compared to histology was 83% (29/35, 95%CI 66-93%) and 93% (14/15, 95%CI 68-100%), respectively. Cross-reactions occurred in urine specimens of patients with Emergomyces africanus infection and in culture filtrates of E. africanus, T. marneffei and Blastomyces species. A commercial Histoplasma EIA had satisfactory accuracy for diagnosis of culture-confirmed histoplasmosis, but cross-reacted in urine specimens from patients with invasive disease caused by the closely-related pathogen, E. africanus and in culture filtrates of E. africanus and other related fungi.

LAY SUMMARY

Emergomyces africanus and Histoplasma capsulatum are fungi that cause a multi-system disease among HIV-seropositive persons with a low CD4 cell count. Handling live cultures of these fungi to confirm a diagnosis requires specialized laboratory equipment and infrastructure which is infrequently accessible in low-resource settings. The features of the two diseases (i.e., disseminated histoplasmosis and emergomycosis) may be indistinguishable when infected tissue is prepared, stained, and examined under a microscope. Enzyme immunoassays (EIA) have been developed as rapid diagnostic tools for the detection of a cell wall component of H. capsulatum in urine specimens, although cross-reactions have been reported in specimens from patients with other fungal infections. We evaluated the accuracy of a commercial Histoplasma EIA to diagnose histoplasmosis and to assess cross-reactions in urine specimens from persons with emergomycosis and in cultures of E. africanus and related fungi. We report a sensitivity and specificity of 88% (95%CI 47-100%) and 72% (95%CI 53-87%) for diagnosis of histoplasmosis compared to culture and 83% (95%CI 66-93%) and 93% (95%CI 68-100%) for diagnosis of either histoplasmosis/emergomycosis compared to a diagnosis made by microscopic examination of infected tissue. The assay cross-reacted in urine specimens from patients with emergomycosis and in culture filtrates of related fungi. Although the EIA cross-reacted with other related fungi, this test can decrease the time to diagnosis and facilitate early treatment of emergomycosis and histoplasmosis in South Africa.

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.

Endemic mycoses: epidemiology and diagnostic strategies

INTRODUCTION

The global frequency of endemic mycoses has considerably increased, mainly due to environmental changes, population growth in endemic areas, and the increase in HIV-related immunosuppressed status. Among the most frequent endemic mycoses are coccidioidomycosis in semi-desert climates, and paracoccidioidomycosis, and histoplasmosis in tropical climates. The inoculum can enter the host through the airway or directly through the skin. Lymphatic and hematogenous spread may involve the skin.

AREAS COVERED

In this article, we provide up-to-date epidemiological and diagnostic data on major (histoplasmosis, paracoccidioidomycosis, coccidioidomycosis, blastomycosis) and minor (talaromycosis, adiaspiromycosis, emergomycosis) endemic mycoses.

EXPERT OPINION

Endemic mycoses include diseases with a localized endemic area, and a few of them converge. These mycoses all have in common the airway involvement and can cause pulmonary symptoms following initial asymptomatic infection. Among the risk groups to acquire these mycoses are travelers from endemic areas, archeologists, speleologists, and immigrants. Promising and useful diagnostic tools have been developed in endemic mycoses; however, most of them are not standardized or available in low-income countries.

Human Blastomycosis in South Africa Caused by Blastomyces percursus and Blastomyces emzantsi sp. nov., 1967 to 2014

We reevaluated 20 cases of blastomycosis diagnosed in South Africa between 1967 and 2014, with Blastomyces dermatitidis considered to be the etiological agent, in light of newly described species and the use of more advanced technologies. In addition to histopathological and/or culture-based methods, all 20 isolates were phenotypically and genotypically characterized, including multilocus typing of five genes and whole-genome sequencing. Antifungal susceptibility testing was performed as outlined by Clinical and Laboratory Standards Institute documents M27-A3 and M38-A2. We merged laboratory and corresponding clinical case data, where available. Morphological characteristics and phylogenetic analyses of five-gene and whole-genome sequences revealed two groups, both of which were closely related to but distinct from B. dermatitidis, Blastomyces gilchristii, and Blastomyces parvus The first group (n = 12) corresponded to the recently described species Blastomyces percursus, and the other (n = 8) is described here as Blastomyces emzantsi sp. nov. Both species exhibited incomplete conversion to the yeast phase at 37°C and were heterothallic for mating types. All eight B. emzantsi isolates belonged to the α mating type. Whole-genome sequencing confirmed distinct species identities as well as the absence of a full orthologue of the BAD-1 gene. Extrapulmonary (skin or bone) disease, probably resulting from hematogenous spread from a primary lung infection, was more common than pulmonary disease alone. Voriconazole, posaconazole, itraconazole, amphotericin B, and micafungin had the most potent in vitro activity. Over the 5 decades, South African cases of blastomycosis were caused by species that are distinct from B. dermatitidis Increasing clinical awareness and access to simple rapid diagnostics may improve the diagnosis of blastomycosis in resource-limited countries.

Disseminated Emergomyces pasteurianus Infection in India: A Case Report and a Review

We report here a case of disseminated Emergomyces pasteurianus infection from India in a patient with AIDS. The patient presented with weight loss, dyspnoea and multiple non-tender skin lesions over face, neck and chest over 3 months. The case was diagnosed by microscopy, histopathology of sample and isolation of fungus from skin lesion, breast nodule, bone marrow and sputum. The identification of the isolates was confirmed by sequencing internal transcribed spacer region of rDNA, beta-tubulin, actin and intein PRP8. The patient responded well to intravenous amphotericin B deoxycholate followed by itraconazole therapy.

Estimated Burden of Fungal Infections in Namibia

Namibia is a sub-Saharan country with one of the highest HIV infection rates in the world. Although care and support services are available that cater for opportunistic infections related to HIV, the main focus is narrow and predominantly aimed at tuberculosis. We aimed to estimate the burden of serious fungal infections in Namibia, currently unknown, based on the size of the population at risk and available epidemiological data. Data were obtained from the World Health Organization (WHO), Joint United Nations Programme on HIV/AIDS (UNAIDS), and published reports. When no data existed, risk populations were used to estimate the frequencies of fungal infections, using the previously described methodology. The population of Namibia in 2011 was estimated at 2,459,000 and 37% were children. Among approximately 516,390 adult women, recurrent vulvovaginal candidiasis (≥4 episodes /year) is estimated to occur in 37,390 (3003/100,000 females). Using a low international average rate of 5/100,000, we estimated 125 cases of candidemia, and 19 patients with intra-abdominal candidiasis. Among survivors of pulmonary tuberculosis (TB) in Namibia 2017, 112 new cases of chronic pulmonary aspergillosis (CPA) are likely, a prevalence of 354 post-TB and a total prevalence estimate of 453 CPA patients in all. Asthma affects 11.2% of adults, 178,483 people, and so allergic bronchopulmonary aspergillosis (ABPA) and severe asthma with fungal sensitization (SAFS) were estimated in approximately 179/100,000 and 237/100,000 people, respectively. Invasive aspergillosis (IA) is estimated to affect 15 patients following leukaemia therapy, and an estimated 0.13% patients admitted to hospital with chronic obstructive pulmonary disease (COPD) (259) and 4% of HIV-related deaths (108) — a total of 383 people. The total HIV-infected population is estimated at 200,000, with 32,371 not on antiretroviral therapy (ART). Among HIV-infected patients, 543 cases of cryptococcal meningitis and 836 cases of Pneumocystis pneumonia are estimated each year. Tinea capitis infections were estimated at 53,784 cases, and mucormycosis at five cases. Data were missing for fungal keratitis and skin neglected fungal tropical diseases such as mycetoma. The present study indicates that approximately 5% of the Namibian population is affected by fungal infections. This study is not an epidemiological study—it illustrates estimates based on assumptions derived from similar studies. The estimates are incomplete and need further epidemiological and diagnostic studies to corroborate, amend them, and improve the diagnosis and management of these diseases.

Emerging Fungal Infections: New Patients, New Patterns, and New Pathogens

The landscape of clinical mycology is constantly changing. New therapies for malignant and autoimmune diseases have led to new risk factors for unusual mycoses. Invasive candidiasis is increasingly caused by non-albicans Candida spp., including C. auris, a multidrug-resistant yeast with the potential for nosocomial transmission that has rapidly spread globally. The use of mould-active antifungal prophylaxis in patients with cancer or transplantation has decreased the incidence of invasive fungal disease, but shifted the balance of mould disease in these patients to those from non-fumigatus Aspergillus species, Mucorales, and Scedosporium/Lomentospora spp. The agricultural application of triazole pesticides has driven an emergence of azole-resistant A. fumigatus in environmental and clinical isolates. The widespread use of topical antifungals with corticosteroids in India has resulted in Trichophyton mentagrophytes causing recalcitrant dermatophytosis. New dimorphic fungal pathogens have emerged, including Emergomyces, which cause disseminated mycoses globally, primarily in HIV infected patients, and Blastomyceshelicus and B. percursus, causes of atypical blastomycosis in western parts of North America and in Africa, respectively. In North America, regions of geographic risk for coccidioidomycosis, histoplasmosis, and blastomycosis have expanded, possibly related to climate change. In Brazil, zoonotic sporotrichosis caused by Sporothrix brasiliensis has emerged as an important disease of felines and people.

Emergomycosis (Emergomyces africanus) in Advanced HIV Disease

In 2013, a novel thermally dimorphic fungal pathogen was described to cause disseminated disease among persons living with advanced HIV/AIDS in South Africa. Although the organism was initially described as an Emmonsia-like fungus, it is now known to belong to a new genus of thermally dimorphic fungi and was recently named Emergomyces africanus. There is considerable clinical and histopathological overlap between emergomycosis and histoplasmosis. This review addresses taxonomic, clinical, diagnostic, and therapeutic aspects of Es. africanus disease, a condition which has, to date, only been reported from southern Africa.

Attempted molecular detection of the thermally dimorphic human fungal pathogen Emergomyces africanus in terrestrial small mammals in South Africa

The ecological niche of Emergomyces africanus (formerly Emmonsia species), a dimorphic fungus that causes an AIDS-related mycosis in South Africa, is unknown. We hypothesized that natural infection with E. africanus occurs in wild small mammals. Using molecular detection with primers specific for E. africanus, we examined 1402 DNA samples from 26 species of mole-rats, rodents, and insectivores trapped in South Africa that included 1324 lung, 37 kidney, and 41 liver specimens. DNA of E. africanus was not detected in any animals. We conclude that natural infection of wild small mammals in South Africa with E. africanus has not been proven.

Emergomyces canadensis, a Dimorphic Fungus Causing Fatal Systemic Human Disease in North America

We report 4 patients in North America with disease caused by Emergomyces canadensis, a newly proposed species of pathogenic dimorphic fungus. Affected persons were immunocompromised; lived in Saskatchewan, Colorado, and New Mexico; and had systemic disease involving blood, skin, cervix, lung, and lymph node. Two cases were fatal.

Name Changes for Fungi of Medical Importance, 2016-2017

This article lists proposed new or revised species names and classification changes associated with fungi of medical importance that were published in the years 2016 and 2017. While many of the revised names listed have been widely adopted without further discussion, some may take longer to achieve more general usage.

Two cases of Emergomyces pasteurianus infection in immunocompromised patients in the Netherlands

We report two cases of Emergomyces pasteurianus infection in the Netherlands. Both patients were immunocompromised and had pulmonary symptoms. The first patient died due to a pulmonary infection with Es. pasteurianus, concomitant listeriosis, Pseudomonas aeruginosa sepsis and invasive pulmonary aspergillosis. The second patient had pulmonary and subcutaneous lesions, and recovered completely after treatment with posaconazole for 14 months. In both cases, diagnosis of Es. pasteurianus was made with internal transcribed spacer rRNA PCR and culture.

Emergomyces africanus in Soil, South Africa

We detected Emergomyces africanus, a thermally dimorphic fungus that causes an HIV-associated systemic mycosis, by PCR in 18 (30%) of 60 soil samples from a wide range of habitats in South Africa. Direct and indirect culture techniques were unsuccessful. Experimental intraperitoneal inoculation of conidia induced murine disease.

Histoplasmosis in Africa: An emerging or a neglected disease?

Histoplasmosis in Africa has markedly increased since the advent of the HIV/AIDS epidemic but is under-recognised. Pulmonary histoplasmosis may be misdiagnosed as tuberculosis (TB). In the last six decades (1952-2017), 470 cases of histoplasmosis have been reported. HIV-infected patients accounted for 38% (178) of the cases. West Africa had the highest number of recorded cases with 179; the majority (162 cases) were caused by Histoplasma capsulatum var. dubuosii (Hcd). From the Southern African region, 150 cases have been reported, and the majority (119) were caused by H. capsulatum var. capsulatum (Hcc). There have been 12 histoplasmin skin test surveys with rates of 0% to 35% positivity. Most cases of Hcd presented as localised lesions in immunocompetent persons; however, it was disseminated in AIDS patients. Rapid diagnosis of histoplasmosis in Africa is only currently possible using microscopy; antigen testing and PCR are not available in most of Africa. Treatment requires amphotericin B and itraconazole, both of which are not licensed or available in several parts of Africa.

Molecular detection of airborne Emergomyces africanus, a thermally dimorphic fungal pathogen, in Cape Town, South Africa

Emergomyces africanus is a thermally dimorphic fungus that causes a systemic mycosis in immunocompromised persons in South Africa. Infection is presumed to follow inhalation of airborne propagules. We developed a quantitative PCR protocol able to detect as few as 5 Es. africanus propagules per day. Samples were collected in Cape Town, South Africa over 50 weeks by a Burkard spore trap with an alternate orifice. We detected Es. africanus in air samples from 34 days (10%) distributed over 11 weeks. These results suggest environmental exposure to airborne Es. africanus propagules occurs more commonly in endemic areas than previously appreciated.

Antifungal Susceptibility of Emerging Dimorphic Pathogens in the Family Ajellomycetaceae

The in vitro susceptibilities of 24 molecularly identified dimorphic fungi belonging to the genera Adiaspiromyces, Blastomyces, and Emergomyces within the family Ajellomycetaceae were tested against 8 standard antifungal agents using CLSI document M38-A2. Amphotericin B and posaconazole had the lowest geometric mean MICs (<0.05 μg/ml) followed by itraconazole (<0.07 μg/ml), voriconazole (<0.15 μg/ml), and isavuconazole (<0.42 μg/ml) while fluconazole was not active. Micafungin demonstrated good in vitro antifungal activity against Emergomyces (geometric mean minimum effective concentration [GM MEC] 0.1 μg/ml) and Blastomyces (GM MEC <0.017 μg/ml).