Impact of COVID-19 on paracoccidioidomycosis. Which was the most influential: The pandemic or the virus?

The impact of COVID-19 on paracoccidioidomycosis (PCM) in Argentina and the consequences generated by the pandemic are discussed. From 2018 to 3 years after the pandemic declaration, 285 proven PCM patients were registered. No association between both diseases was documented. PCM frequency decreased to extremely low levels in 2020. Mandatory social isolation and the emotional and psychological effects generated under pandemic circumstances led to delays in diagnosis, severe disseminated cases, and other challenges for diagnosis in subsequent years. Probable underdiagnosis should be considered due to the overlap of clinical manifestations, the low index of suspicion and the lack of sensitive diagnostic tools.

Clinical and Demographic Features of Paracoccidioidomycosis in Argentina: A Multicenter Study Analysis of 466 Cases.

Information on paracoccidioidomycosis (PCM) in Argentina is fragmented and has historically been based on estimates, supported only by a series of a few reported cases. Considering the lack of global information, a national multicentric study in order to carry out a more comprehensive analysis was warranted. We present a data analysis including demographic and clinical aspects of a historical series of 466 cases recorded over 10 years (2012-2021). Patients were aged from 1 to 89 years. The general male: female (M:F) ratio was 9.5:1 with significant variation according to the age group. Interestingly, the age range 21-30 shows an M:F ratio of 2:1. Most of the cases (86%) were registered in northeast Argentina (NEA), showing hyperendemic areas in Chaco province with more than 2 cases per 10,000 inhabitants. The chronic clinical form occurred in 85.6% of cases and the acute/subacute form occurred in 14.4% of cases, but most of these juvenile type cases occurred in northwestern Argentina (NWA). In NEA, the incidence of the chronic form was 90.6%; in NWA, the acute/subacute form exceeded 37%. Diagnosis by microscopy showed 96% positivity but antibody detection displays 17% of false negatives. Tuberculosis was the most frequent comorbidity, but a diverse spectrum of bacterial, fungal, viral, parasitic, and other non-infectious comorbidities was recorded. This national multicenter registry was launched in order to better understand the current status of PCM in Argentina and shows the two endemic zones with a highly diverse epidemiology.

Genomic diversity of the human pathogen Paracoccidioides across the South American continent.

Paracoccidioidomycosis (PCM) is a life-threatening systemic mycosis widely reported in the Gran Chaco ecosystem. The disease is caused by different species from the genus Paracoccidioides, which are all endemic to South and Central America. Here, we sequenced and analyzed 31 isolates of Paracoccidioides across South America, with particular focus on isolates from Argentina and Paraguay. The de novo sequenced isolates were compared with publicly available genomes. Phylogenetics and population genomics revealed that PCM in Argentina and Paraguay is caused by three distinct Paracoccidioides genotypes, P. brasiliensis (S1a and S1b) and P. restrepiensis (PS3). P. brasiliensis S1a isolates from Argentina are frequently associated with chronic forms of the disease. Our results suggest the existence of extensive molecular polymorphism among Paracoccidioides species, and provide a framework to begin to dissect the connection between genotypic differences in the pathogen and the clinical outcomes of the disease.

Emergence of acute/subacute infant-juvenile paracoccidioidomycosis in Northeast Argentina: Effect of climatic and anthropogenic changes?

Argentina has two endemic areas of paracoccidioidomycosis (PCM). Bordering Paraguay and Brazil, Northeast Argentina (NEA) comprises the area with the highest incidence where the chronic adult clinical form has historically been reported. Juvenile form in children and adolescents is rare in this area since only one case was reported in the last 10 years. Despite this, between 2010 and 2012, several cases of acute/subacute clinical forms in children aged 10 to 16 (median 12) were detected. In the last decade, the NEA region has been exposed to ecological variations as consequences of certain climatic and anthropogenic changes, including El Niño-Southern Oscillation phenomenon during 2009, and deforestation. The region has also suffered from the significant ecological effects of the construction of one of the biggest hydroelectric dams of South America. This study aims to describe clinical and epidemiological aspects of acute/subacute PCM cases detected in children from NEA and to discuss climatic and anthropogenic changes as possible contributing factors in the emergence of this disease in children. This acute/subacute PCM cluster was characterized by severe disseminated and aggressive presentations to localized form, with a high spectrum of clinical manifestations uncommonly observed. Due to the lack of experience in acute/subacute PCM in children in the studied area and the atypical clinical manifestations observed, the diagnosis was delayed. In order to avoid misdiagnosis, a higher level of suspicion is now required in NEA and countries bordering the southern part of the endemic area, which are affected by the changes discussed in this article.

Cavitary Pulmonary Sporotrichosis: Case Report and Literature Review.

A case of cavitary pulmonary sporotrichosis without mucocutaneous involvement caused by Sporothrix schenckii is reported in a sexagenarian woman with a long smoking history. The patient was hospitalized for septic shock with multiorgan failure from a respiratory focus. The diagnosis was delayed due to the fungal etiological agent was not initially considered in the differential diagnosis. A good clinical and radiological evolution was obtained with the antifungal therapy. Occasional cases of primary pulmonary sporotrichosis have been reported in the literature. Due to its low incidence, this is a less-known and underestimated clinical form. Both clinical suspicion and microbiological studies are needed to reach pulmonary sporotrichosis diagnosis.

Identification of Candida parapsilosis Sensu Lato in Pediatric Patients and Antifungal Susceptibility Testing.

A total of 59 Candida parapsilosis sensu stricto and 1 Candida orthopsilosis recovered from catheters and blood cultures of pediatric patients from the northeastern region of Argentina were studied. Susceptibility to azoles, amphotericin B, and echinocandins was tested by the broth microdilution method. According to CLSI clinical breakpoints, >91% of the strains were azole susceptible, whereas 15% showed high amphotericin B MICs.

In Vivo Paracoccidioides sp. Biofilm on Vascular Prosthesis.

Paracoccidioidomycosis is an endemic mycosis caused by Paracoccidioides species limited to Latin America arising with the chronic form in 90% of cases. The capacity of microorganisms to form biofilms is considered of great importance medical since can contribute to the persistence and to the chronic state of the diseases. The ability of Paracoccidioides to form biofilm has been demonstrated in vitro. In our study, for the first time we have observed this capability in vivo on a vascular prosthesis using scanning electron microscope showing a dense network of Paracoccidioides yeasts covered by an extracellular matrix.

Native trees of the Northeast Argentine: natural hosts of the Cryptococcus neoformans-Cryptococcus gattii species complex.

BACKGROUND: In Argentina, information about epidemiology and environmental distribution of Cryptococcus is scarce. The city of Resistencia borders with Brazil and Paraguay where this fungus is endemic. All these supported the need to investigate the ecology of the genus and the epidemiology of cryptococcosis in this area. AIMS: The aim was to investigate the presence of species of Cryptococcus neoformans-Cryptococcus gattii complex and their genotypes in trees of the city of Resistencia. METHODS: One hundred and five trees were sampled by swabbing technique. The isolates were identified using conventional and commercial methods and genotyped by PCR-RFLP (Restriction Fragment Length Polymorphism). RESULTS: Cryptococcus was found in 7 out of the total trees. 6 out of 7 Cryptococcus isolates were identified as C. neoformans and one as C. gattii. C. gattii was isolated from Grevillea robusta. C. neoformans strains were isolated from Tabebuia avellanedae and Peltophorum dubium. Genotyping showed that all C. neoformans belonged to the VNI type and C. gattii belonged to the VGI type. CONCLUSIONS: This represents the first study on the ecology of Cryptococcus spp. associated to trees from northeastern Argentina, and the first report describing Grevillea robusta as a host of members of this fungal genus. Another finding is the isolation of C. neoformans from Tabebuia avellanedae and Peltophorum dubium, both tree species native to northeastern Argentina.