Geographical evaluation of Neuroparacoccidioidomycosis and Paracoccidioidomycosis in Southern Brazil

Gene expression of Paracoccidioides virulence factors after interaction with macrophages and fibroblasts

BACKGROUND

Paracoccidioidomycosis (PCM) is a systemic mycosis with high prevalence in Latin America that is caused by thermodimorphic fungal species of the Paracoccidioides genus.

OBJECTIVES

In this study, we used quantitative polymerase chain reaction (qPCR) to investigate the expression of genes related to the virulence of Paracoccidioides brasiliensis (Pb18) and P. lutzii (Pb01) strains in their mycelial (M) and yeast (Y) forms after contact with alveolar macrophages (AMJ2-C11 cell line) and fibroblasts (MRC-5 cell line).

METHODS

The selected genes were those coding for 43 kDa glycoprotein (gp43), enolase, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), 14-3-3 protein (30 kDa), phospholipase, and aspartyl protease.

FINDINGS

In the Pb18 M form, the aspartyl protease gene showed the highest expression among all genes tested, both before and after infection of host cells. In the Pb18 Y form after macrophage infection, the 14-3-3 gene showed the highest expression among all genes tested, followed by the phospholipase and gp43 genes, and their expression was 50-fold, 10-fold, and 6-fold higher, respectively, than that in the M form. After fibroblast infection with the Pb18 Y form, the 14-3-3 gene showed the highest expression, followed by the phospholipase and aspartyl protease genes, and their expression was 25-fold, 10-fold, and 10-fold higher, respectively, than that in the M form. Enolase and aspartyl protease genes were expressed upon infection of both cell lines. After macrophage infection with the Pb01 Y form, the 14-3-3 gene showed the highest expression, followed by the phospholipase and aspartyl protease genes, and their expression was 18-fold, 12.5-fold, and 6-fold higher, respectively, than that in the M form.

MAIN CONCLUSIONS

In conclusion, the data show that the expression of the genes analysed may be upregulated upon fungus-host interaction. Therefore, these genes may be involved in the pathogenesis of paracoccidioidomycosis.

A single-centre, retrospective study of the incidence of invasive fungal infections during 85 years of autopsy service in Brazil

Autopsy continues to play an essential role in monitoring opportunistic fungal infections. However, few studies have analysed the historical trends of fungal infections in autopsies. Here, we analyse available data on fungal infections obtained from autopsy reports during 85 years of autopsies performed by the largest autopsy service in Brazil. All invasive fungal infections presented in autopsy reports between 1930 and 2015 were included. Of the 158,404 autopsy reports analysed, 1096 involved invasive fungal infections. In general, paracoccidioidomycosis (24%) was the most frequent infection, followed by candidiasis (18%), pneumocystosis (11.7%), cryptococcosis (11%), aspergillosis (11%) and histoplasmosis (3.8%). Paracoccidioidomycosis decreased after the 1950s, whereas opportunistic fungal infections increased steadily after the 1980s during the peak of the AIDS pandemic. The lung was the most frequently affected organ (73%). Disseminated infection was present in 64.5% of cases. In 26% of the 513 cases for which clinical charts were available for review, the diagnosis of opportunistic fungal infections was performed only at autopsy. Our unique 85-year history of autopsies showed a transition from endemic to opportunistic fungal infections in São Paulo, Brazil, reflecting increased urbanization, the appearance of novel diseases, such as AIDS in the 1980s, and advances in medical care over time.

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.

Isolated neuroparacoccidioidomycosis as a pseudotumoral lesion in the absence of systemic disease

Background:

Paracoccidioidomycosis (PCM) is a systemic, progressive, noncontagious, and often chronic disease caused by the fungus Paracoccidioides brasiliensis that rarely affects the central nervous system (CNS). The condition is usually treated using antifungal drugs, and some cases may require surgery.

Case Description:

A 55-year-old man, a smoker, without known comorbidities, was referred to the neurosurgery team with a history of a single epileptic seizure a week before hospital admission followed by progressive right- sided hemiparesis. Head computed tomography and brain magnetic resonance imaging showed an intra-axial expansive lesion affecting the left parietal lobe, associated with extensive edema and a regional compressive effect producing slight subfalcine herniation that was initially managed as an abscess. After the failure of antibiotic treatment, the patient underwent a neurosurgical procedure for excision of the lesion. Histopathological analysis revealed that it was PCM and there was no evidence of impairment of other systems due to the disease.

Conclusion:

PCM can be a serious, debilitating disease and is potentially fatal. Although isolated CNS involvement is rare, it must be considered, especially in endemic areas, as late diagnosis and treatment severely decreases good outcome rates.

Re-drawing the Maps for Endemic Mycoses

Endemic mycoses such as histoplasmosis, coccidioidomycosis, blastomycosis, paracoccidioidomycosis, and talaromycosis are well-known causes of focal and systemic disease within specific geographic areas of known endemicity. However, over the past few decades, there have been increasingly frequent reports of infections due to endemic fungi in areas previously thought to be “non-endemic.” There are numerous potential reasons for this shift such as increased use of immune suppressive medications, improved diagnostic tests, increased disease recognition, and global factors such as migration, increased travel, and climate change. Regardless of the causes, it has become evident that our previous understanding of endemic regions for these fungal diseases needs to evolve. The epidemiology of the newly described Emergomyces is incomplete; our understanding of it continues to evolve. This review will focus on the evidence underlying the established areas of endemicity for these mycoses as well as new data and reports from medical literature that support the re-thinking these geographic boundaries. Updating the endemic fungi maps would inform clinical practice and global surveillance of these diseases.