The World Health Organization, in response to the growing burden of fungal disease, established a process to develop a fungal pathogen priority list. This systematic review aimed to evaluate the epidemiology and impact of infections caused by Talaromyces marneffei, Coccidioides species, and Paracoccidioides species. PubMed and Web of Sciences databases were searched to identify studies published between 1 January 2011 and 23 February 2021 reporting on mortality, complications and sequelae, antifungal susceptibility, preventability, annual incidence, and trends. Overall, 25, 17, and 6 articles were included for T. marneffei, Coccidioides spp. and Paracoccidioides spp., respectively. Mortality rates were high in those with invasive talaromycosis and paracoccidioidomycosis (up to 21% and 22.7%, respectively). Hospitalization was frequent in those with coccidioidomycosis (up to 84%), and while the duration was short (mean/median 3-7 days), readmission was common (38%). Reduced susceptibility to fluconazole and echinocandins was observed for T. marneffei and Coccidioides spp., whereas >88% of T. marneffei isolates had minimum inhibitory concentration values ≤0.015 μg/ml for itraconazole, posaconazole, and voriconazole. Risk factors for mortality in those with talaromycosis included low CD4 counts (odds ratio 2.90 when CD4 count <200 cells/μl compared with 24.26 when CD4 count <50 cells/μl). Outbreaks of coccidioidomycosis and paracoccidioidomycosis were associated with construction work (relative risk 4.4-210.6 and 5.7-times increase, respectively). In the United States of America, cases of coccidioidomycosis increased between 2014 and 2017 (from 8232 to 14 364/year). National and global surveillance as well as more detailed studies to better define sequelae, risk factors, outcomes, global distribution, and trends are required.

BACKGROUND: Accurate diagnosis of paracoccidioidomycosis is crucial for improving patient outcomes. Paracoccidioides antibody detection by double immunodiffusion (DID) is a convenient diagnostic tool, but testing performance can vary based on certain factors.
METHODS: We assessed DID performance using a commercially prepared Paracoccidioides reagents (IMMY, USA), involving 40 serum specimens, including 20 from patients with proven paracoccidioidomycosis and 20 from patients without the disease. The DID test demonstrated a sensitivity of 90% (95% CI=68%-99%) and a specificity of 100% (95% CI=83%-100%).
CONCLUSIONS: Our findings suggest that DID using commercial reagents may provide a feasible tool with satisfactory testing performance for anti-Paracoccidioides antibody detection.

Blood count is crucial for assessing bone marrow\'s cell production and differentiation during infections, gaging disease severity, and monitoring therapeutic responses. The profile of blood count in chronic forms of paracoccidioidomycosis (PCM) has been insufficiently explored. To better understand the changes in hematological cells in different stages of the PCM chronic form, we evaluated the blood count, including immature blood cells in automated equipment, before and during the treatment follow-up of 62 chronic PCM patients. Predominantly male (96.8%) with an average age of 54.3 (standard deviation SD 6.9) years, participants exhibited pre-treatment conditions such as anemia (45.2%), monocytosis (38.7%), and leukocytosis (17.7%), which became less frequent after clinical cure. Anemia was more prevalent in severe cases. Notably, hemoglobin and reticulocyte hemoglobin content increased, while leukocytes, monocytes, neutrophils, immature granulocytes, and platelets decreased. Chronic PCM induced manageable hematological abnormalities, mainly in the red blood series. Monocytosis, indicating monocytes\' role in PCM\'s immune response, was frequent. Post-treatment, especially after achieving clinical cure, significant improvements were observed in various hematological indices, including immature granulocytes and reticulocyte hemoglobin content, underscoring the impact of infection on these parameters.

Cutaneous involvement in paracoccidioidomycosis (PCM) can exhibit a highly polymorphic spectrum. The infiltrative pattern corresponds to up to 26.6% of observed skin lesions, including sarcoid-like plaques, a rare presentation of cutaneous lesions in PCM. This clinical expression is almost exclusively cutaneous, and its histology reveals a tuberculoid granuloma with a scarcity of fungi, leading to misdiagnosis as other granulomatous diseases. Here, we report a rare form of chronic multifocal paracoccidioidomycosis manifesting as sarcoid-like skin lesions misdiagnosed as granulomatous rosacea in a patient with severe systemic disease.

The incidence of paracoccidioidomycosis (PCM) varies in Latin America, and it is influenced by environmental factors. This study evaluated the distribution of PCM acute/subacute form (AF) cases and their correlation with geoclimatic factors in the Mato Grosso do Sul (MS) state. The study included 81 patients diagnosed with the PCM/AF at the University Hospital of the Federal University of Mato Grosso do Sul between January 1980 and February 2022. Geographic coordinates, health microregion of patient\'s residence, compensated average temperature, relative air humidity (RH), El Niño Southern Oscillation (ENSO), and average global temperature were analyzed. The highest incidence was observed in the Aquidauana (7/100,000 inhabitants), while Campo Grande, the state\'s capital, had the highest number (n = 34; 42.4%) and density (4.4 cases/km2) of cases. The number of cases increased during extended periods of the El Niño phenomenon. A positive correlation was found between higher RH and PCM/AF cases. Most PCM/AF cases were found in areas with loamy soils and RH ranging from 60.8 to 73.6%. In MS, the health microregions of PCM/AF patients are characterized by deforestation for agricultural and pasture use, coupled with loamy soils and specific climatic phenomena leading to higher soil humidity.

Co-occurrence of paracoccidioidomycosis and strongyloidiasis in immunosuppressed patients, particularly those infected with human T-lymphotropic virus type 1/2, is infrequent. We describe the case of a Peruvian farmer from the central jungle with human T-lymphotropic virus type 1/2 infection, with 2 months of illness characterized by respiratory and gastrointestinal symptoms associated with fever, weight loss, and enlarged lymph nodes. Strongyloides stercoralis and Paracoccidioides brasiliensis were isolated in sputum and bronchoalveolar lavage samples, respectively. The clinical evolution was favorable after the patient received ivermectin and amphotericin B. We hypothesize that autoinfestation by S. stercoralis in human T-lymphotropic virus type 1/2-infected patients may contribute to the disseminated presentation of Paracoccidioides spp. Understanding epidemiological context is crucial for suspecting opportunistic regional infections, particularly those that may coexist in immunosuppressed patients.

Paracoccidioides fungi are thermodimorphic microorganisms that cause paracoccidioidomycosis (PCM), an autochthonous disease from Latin America, with most cases in Brazil. Humans become infected by inhaling conidia or mycelial fragments that transform into yeast at body temperature. These fungi cause chronic-granulomatous inflammation, which may promote fibrosis and parenchyma destruction in the lungs. In response to stress imposed by the host, fungi Paracoccidioides spp. increase the expression of heat shock proteins (HSP), which protect them by sustaining cellular proteostasis. Our group has studied the role of HSP60 in PCM, and previous data show that the recombinant HSP60 (rHSP60) has a deleterious effect when used in a single dose as therapy for experimental PCM. Here, we investigated the mechanism by which rHSP60 could worsen the disease. We found that rHSP60 caused the viability loss of splenic or lymph node cells from both immunized and non-immunized mice, including in splenic T lymphocytes under polyclonal stimulation with concanavalin A, probably by undergoing apoptosis. Among analyzed splenic cells, lymphocytes were indeed the main cells to die. When we investigated the death mechanisms, remarkably, we found that there was no viability loss in rHSP60-stimulated splenic cells from mice deficient in Toll-like receptor 4, TRIF adapter protein, and TNF receptor 1(TNFR1), as well as rHSP60-stimulated WT cells incubated with anti-TNF antibody. Besides, caspase-8 inhibitor IETD-CHO blocked the rHSP60 effect on splenic cells, suggesting that rHSP60 induces the extrinsic apoptosis pathway dependent on signaling via TLR4/TRIF and TNFR1.

Extracellular vesicles (EVs) are membrane-enclosed nanoparticles that transport several biomolecules and are involved in important mechanisms and functions related to the pathophysiology of fungal diseases. EVs from Paracoccidioides brasiliensis, the main causative agent of Paracoccidioidomycosis (PCM), modulate the immune response of macrophages. In this study, we assessed the EVs proteome from a virulent P. brasiliensis isolated from granulomatous lesions and compared their immunomodulatory ability with EVs isolated from the fungus before the animal passage (control EVs) when challenging macrophages and dendritic cells (DCs). Proteome showed that virulent EVs have a higher abundance of virulence factors such as GP43, protein 14-3-3, GAPDH, as well as virulence factors never described in PCM, such as aspartyl aminopeptidase and a SidJ analogue compared with control EVs. Virulent extracellular vesicles induced higher expression of TLR4 and Dectin-1 than control EVs in macrophages and dendritic cells (DCs). In opposition, a lower TLR2 expression was induced by virulent EVs. Additionally, virulent EVs induced lower expression of CD80, CD86 and TNF-α, but promoted a higher expression of IL-6 and IL-10, suggesting that EVs isolated from virulent P. brasiliensis-yeast promote a milder DCs and macrophage maturation. Herein, we showed that EVs from virulent fungi stimulated a higher frequency of Th1/Tc1, Th17, and Treg cells, which gives new insights into fungal extracellular vesicles. Taken together, our results suggest that P. brasiliensis utilizes its EVs as virulence bags that manipulate the immune system in its favour, creating a milder immune response and helping with fungal evasion from the immune system.

Immune checkpoint pathways, i.e., coinhibitory pathways expressed as feedback following immune activation, are crucial for controlling an excessive immune response. Cytotoxic T lymphocyte antigen-4 (CTLA-4) and programmed cell death protein-1 (PD-1) are the central classical checkpoint inhibitory (CPI) molecules used for the control of neoplasms and some infectious diseases, including some fungal infections. As the immunosuppression of severe paracoccidioidomycosis (PCM), a chronic granulomatous fungal disease, was shown to be associated with the expression of coinhibitory molecules, we hypothesized that the inhibition of CTLA-4 and PD-1 could have a beneficial effect on pulmonary PCM. To this end, C57BL/6 mice were infected with Paracoccidioides brasiliensis yeasts and treated with monoclonal antibodies (mAbs) α-CTLA-4, α-PD-1, control IgG, or PBS. We verified that blockade of CTLA-4 and PD-1 reduced the fungal load in the lungs and fungal dissemination to the liver and spleen and decreased the size of pulmonary lesions, resulting in increased survival of mice. Compared with PBS-treated infected mice, significantly increased levels of many pro- and anti-inflammatory cytokines were observed in the lungs of α-CTLA-4-treated mice, but a drastic reduction in the liver was observed following PD-1 blockade. In the lungs of α-CPI and IgG-treated mice, there were no changes in the frequency of inflammatory leukocytes, but a significant reduction in the total number of these cells was observed. Compared with PBS-treated controls, α-CPI- and IgG-treated mice exhibited reduced pulmonary infiltration of several myeloid cell subpopulations and decreased expression of costimulatory molecules. In addition, a decreased number of CD4+ and CD8+ T cells but sustained numbers of Th1, Th2, and Th17 T cells were detected. An expressive reduction in several Treg subpopulations and their maturation and suppressive molecules, in addition to reduced numbers of Treg, TCD4+, and TCD8+ cells expressing costimulatory and coinhibitory molecules of immunity, were also detected. The novel cellular and humoral profiles established in the lungs of α-CTLA-4 and α-PD-1-treated mice but not in control IgG-treated mice were more efficient at controlling fungal growth and dissemination without causing increased tissue pathology due to excessive inflammation. This is the first study demonstrating the efficacy of CPI blockade in the treatment of pulmonary PCM, and further studies combining the use of immunotherapy with antifungal drugs are encouraged.

BACKGROUND: This study standardized a semi-quantitative dot blotting assay (DB) and a quantitative real-time polymerase chain reaction (qPCR) to detect specific antibodies for Paracoccidioides brasiliensis and its DNA in PCM patients.
METHODS: We evaluated 42 confirmed PCM patients upon admission using a serological double agar gel immunodiffusion test (DID), DB, and molecular tests (qPCR in total blood). The control groups included 42 healthy individuals and 37 patients with other infectious diseases. The serological progress during treatment was evaluated in eight patients, and there was a relapse diagnosis in ten patients using the Pb B.339 strain antigen. The cut-off points for the serological tests were determined by a receiver operator characteristic curve.
RESULTS: The DB and DID tests showed similar accuracy, but the DB identified lower antibody concentrations. Cross-reactions were absent in the DB assay. In the relapse diagnoses, DB exhibited much higher sensitivity (90%) than DID (30%).
CONCLUSIONS: A DB assay is easier and faster than a DID test to be performed; DB and DID tests show the same accuracy, while blood qPCR is not recommended in the diagnosis at the time of admission; cross-reactions were not observed with other systemic diseases; DB and DID tests are useful for treatment monitoring PCM patients; and a DB assay is the choice for diagnosing relapse. These findings support the introduction of semi-quantitative DB assays in clinical laboratories.