Dataset Information

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

ABSTRACT: 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.

SUBMITTER: Schwartz IS

PROVIDER: S-EPMC5800596 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

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

Schwartz Ilan S IS McLoud Josh D JD Berman Dilys D Botha Alfred A Lerm Barbra B Colebunders Robert R Levetin Estelle E Kenyon Chris C

PLoS neglected tropical diseases 20180122 1

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 ...[more]

PMID: 29357352

Similar Datasets

Project description: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.

Project description:Pulmonary endarterectomy (PEA) is the only definitive and potentially curative therapy for chronic thromboembolic pulmonary hypertension (CTEPH), associated with impressive improvements in symptoms and haemodynamics. However, it is only offered at a few centres in South Africa. The characteristics and outcomes of patients undergoing PEA in Cape Town have not been reported previously. To assess the difference in World Health Organization functional class (WHO-FC) before and at least 6 weeks after surgery. We interrogated the adult cardiothoracic surgery database at the University of Cape Town between December 2005 and April 2021 for patients undergoing PEA at Groote Schuur Hospital and a private hospital. A total of 32 patients underwent PEA, of whom 8 were excluded from the final analysis owing to incomplete data or a histological diagnosis other than CTEPH. The work-up of these patients for surgery was variable: all had a computed tomography pulmonary angiogram, 7 (29%) had a ventilation/perfusion scan, 5 (21%) underwent right heart catheterisation, and none had a pulmonary angiogram. The perioperative mortality was 4/24 (17%): 1 patient (4%) had a cardiac arrest on induction of anaesthesia, 2 patients (8%) died of postoperative pulmonary haemorrhage, and 1 patient (4%) died of septic complications in the intensive care unit. Among the survivors, the median (interquartile range) improvement in WHO-FC was 2 (1 - 3) classes (p=0.0004); 10/16 patients (63%) returned to a normal baseline (WHO-FC I). Even in a low-volume centre, PEA is associated with significant improvements in WHO-FC and a return to a normal baseline in survivors. What the study adds. South African patients undergoing pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) have a marked improvement in functional status, with many returning to a normal functional baseline. However, the small number of patients included in this study indicates that PEA is probably underutilised. Pre- and postoperative assessment is inconsistent, despite availability of established guidelines.Implications of the findings. More patients should be referred to specialist centres for assessment for this potentially curative procedure. Use of guidelines to standardise investigations and monitoring of patients with CTEPH may improve patient selection for surgery.

Project description:Coccidioides spp. are mammalian fungal pathogens endemic to the Southwestern US and other desert regions of Mexico, Central and South America, with the bulk of US infections occurring in California and Arizona. In the soil, Coccidioides grows in a hyphal form that differentiates into 3-5 micron asexual spores (arthroconidia). When arthroconidia are inhaled by mammals they undergo a unique developmental transition from polar hyphal growth to isotropic expansion with multiple rounds of nuclear division, prior to segmentation, forming large spherules filled with endospores. Very little is understood about the molecular basis of spherule formation. Here we characterize the role of the conserved transcription factor Ryp1 in Coccidioides development. We show that Coccidioides Δryp1 mutants have altered colony morphology under hypha-promoting conditions and are unable to form mature spherules under spherule-promoting conditions. We analyze the transcriptional profile of wild-type and Δryp1 mutant cells under hypha- and spherule-promoting conditions, thereby defining a set of hypha- or spherule-enriched transcripts ("morphology-regulated" genes) that are dependent on Ryp1 for their expression. Forty percent of morphology-regulated expression is Ryp1-dependent, indicating that Ryp1 plays a dual role in both hyphal and spherule development. Ryp1-dependent transcripts include key virulence factors such as SOWgp, which encodes the spherule outer wall glycoprotein. Concordant with its role in spherule development, we find that the Δryp1 mutant is completely avirulent in the mouse model of coccidioidomycosis, indicating that Ryp1-dependent pathways are essential for the ability of Coccidioides to cause disease. Vaccination of C57BL/6 mice with live Δryp1 spores does not provide any protection from lethal C. posadasii intranasal infection, consistent with our findings that the Δryp1 mutant fails to make mature spherules and likely does not express key antigens required for effective vaccination. Taken together, this work identifies the first transcription factor that drives mature spherulation and virulence in Coccidioides.

Dataset Information

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

Publications

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

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets