Evaluation of Paracoccidioides brasiliensis infection by gp 43 intradermal test in rural settlements in Central-West Brazil

Talaromyces marneffei, Coccidioides species, and Paracoccidioides species-a systematic review to inform the World Health Organization priority list of fungal pathogens

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.

A Case-Control Study of Paracoccidioidomycosis in Women: The Hormonal Protection Revisited

Clinical observations have long suggested that women are protected against paracoccidioidomycosis. 17β-estradiol, the main female estrogen, inhibits conidia-to-yeast transformation (C-to-Y), which is required for the infection establishment. However, experiments in murine models have yielded conflicting results, suggesting that C-to-Y inhibition, alone, fails to explain the female-associated protection and that sexual hormones may also act by modulating the host’s immune responses. Therefore, this issue remains unsolved. Strikingly, no studies have compared the severity of paracoccidioidomycosis between men and women. This retrospective case-control study compared 36 women with 72 age-matched men for clinical–demographic, laboratory, and chest imaging findings. Overall, paracoccidioidomycosis in women presented the main features described in the acute/subacute and chronic forms seen in men. Women also showed similar demographic features and clinical–laboratory and imaging severity scores as men. We additionally reviewed 58 paracoccidioidin skin test surveys undertaken by volunteers from endemic areas. Data accumulated from 10.873 tests showed that females and males are infected with similar magnitudes (21.9% vs. 25.2%) and that reactivity steadily increased with age, peaking after the age of 60. We discuss the paradox of similar infection rates but much lower disease prevalence in women, considering the current pathogenetic views of paracoccidioidomycosis, and we raise alternative hypotheses to account for this paradox.

IgG reactivity profile to Paracoccidioides spp. antigens in people with asymptomatic Paracoccidioidomycosis

Introduction. Paracoccidioidomycosis (PCM) is a systemic mycosis caused by Paracoccidioides spp. As the disease is known to affect mostly men over 40 years old who previously worked handling soil, some cities of agricultural economy in endemic regions may have more cases of paracoccidioidal infection.Gap statement. The true frequency of PCM cannot be established in Brazil because it is not a disease of mandatory reporting. The detection of paracoccidioidal infection may assist in the planning of health services, in order to provide early detection of the disease and to prevent its worsening or even progression to death. In addition, little is described about sera reactivity with antigens from different species of Paracoccidiodes, especially P. lutzii.Aim. Current research was conducted in an inland municipality of southern Brazil, in order to assess infection rate within this endemic region of PCM disease.Methodology. ELISA was employed to evaluate 359 sera from random volunteers from Guarapuava, Paraná, Brazil, to detect IgG against cell-free antigens (CFA) from P. restrepiensis B339, P. americana LDR3 and P. lutzii LDR2. Confirmatory ELISA employed gp43 from B339. Reduction of cross-reactions was sought by treatment with sodium metaperiodate (SMP-CFA, SMP-gp43). Immunoblot was performed with 37 selected sera among those reactive in ELISA. Epidemiological profile was assessed by questionnaire.Results. ELISA reactivity was: CFA/SMP-CFA in general 37.3/17.8 %, B339 25.3/14.5 %, LDR3 24.5/1.4 %, LDR2 8.3/5.8 %; gp43/SMP-gp43 7.2/4.7 %. There were sera reactive with multiple CFAs. In immunoblot, five sera showed the same reaction profile with P. lutzii's antigens as PCM disease sera. Rural residence and soil-related professions were risk factors for paracoccidioidal infection.Conclusion. The low prevalence is in accordance with previous reports of lower PCM disease endemicity in Guarapuava than in other areas of Paraná. Although P. brasiliensis seems to be the prevalent strain of the region, 21 sera from people who only lived in Guarapuava reacted with P. lutzii LDR2. CFA-ELISA with whole antigens seems a good option for serological screening in epidemiological surveys.

Pathogenesis and Classification of Paracocidioidomycosis: New Insights From Old Good Stuff

Different classifications of paracoccidioidomycosis emerged since its discovery in 1908, culminating in the proposition of a simplified and consensual one in 1987. However, by revisiting these classifications, case reports, or case series from which the authors based their own, we found many patients who did not fit in either the 1987 classification or in the correspondent natural history/pathogenesis view. In this report, the concepts of paracoccidioidomycosis infection, primary pulmonary paracoccidioidomycosis (PP-PCM), and other subclinical forms of PCM are reassessed. A classification is proposed to encompass all these subtle but distinct outcomes. I suggest a continuum between the PP-PCM and the overt chronic form of disease, and not the current view of quiescent foci, frozen in time and suddenly reactivated for unknown reasons. Failure to fully resolve the infection in its initial stages is a conceivable hypothesis for the chronic form. The proposed clinical classification might offer new insights to better characterize and manage PCM patients.

An autochthonous case of paracoccidioidomycosis in a new area of Ceara State, Northeastern Brazil

The largest endemic areas of paracoccidioidomycosis (PCM) in Brazil comprise the humid agricultural regions of the Southeast, South, and, recently, the Midwest and North regions. The Ceara State, located in the Brazilian Northeast region, presents semi-arid climate in most of its territory, characterized by high temperatures, scarce vegetation and low humidity. The objective of the present study was to describe a new autochthonous case of paracoccidioidomycosis from a distinct area of Ceara and review the characteristics of PCM occurrence in Northeastern Brazil. The patient was a 65-year-old male farmer who denied traveling outside the Ceara State or living in other locations. He was born and lived in the rural area known as Camara, bordering the municipalities of Itapaje and Itapipoca. Camara is one of the highest areas (around 720 m of altitude) of the Uruburetama mountains that exhibits tropical forests and is located in Northern Ceara, distant 139 km from the capital, Fortaleza. The patient sought for care, complaining of an oral lesion that appeared over the past three years. The hard palate lesion biopsy revealed multinucleated cells with cytoplasmic inclusions, compatible with PCM. After culture, P. brasiliensis was identified by polymerase chain reaction. Serological testing for PCM was reagent. The patient was treated with itraconazole for approximately 17 months, persisting free of symptoms after 15 months of follow-up. Regarding this new autochthonous case in the Ceara State, PCM should be considered in the differential diagnosis of patients with suggestive clinical manifestations, proceeding from the mountainous areas of Ceara.

Intradermal injection of Pythium insidiosum protein antigens for improved diagnosis and treatment of pythiosis in an experimental model

The oomycetous pathogen Pythium insidiosum is the causative agent of pythiosis, a life-threatening disease that affects animals and humans. This infectious disease is difficult to treat, and early and accurate diagnosis is critical for effective treatment. In this sense, this study aimed to evaluate the intradermal (ID) injection of P. insidiosum protein antigens (PiPA) for the diagnosis and treatment of pythiosis using an experimental model. For diagnostic purposes, PiPA were injected by the ID route in the following groups of rabbits: (a) control; (b) previously immunized with PiPA injected by the subcutaneous (SC) route; and (c) infected with P. insidiosum zoospores. For treatment purposes, rabbits with pythiosis were also treated with PiPA by the ID or SC routes. Mean induration sizes were different at 24 h and 72 h readings when compared to the control group. Sensitivity of the protocol was 100% at 24 h and 80% at 72 h, with 100% specificity in both readings. PiPA treatment using ID or SC routes did not result in significant differences in lesion sizes and cure rates; however, serum levels of interferon-gamma were higher in SC route. This study demonstrates the applicability of PiPA ID for diagnosis and treatment of pythiosis in an experimental model.

Study of differential expression of miRNAs in lung tissue of mice submitted to experimental infection by Paracoccidioides brasiliensis

MicroRNAs (miRNAs) are small single stranded RNA sequences involved in post-transcriptional regulation of different biological and physiological processes. Paracoccidioidomycosis (PCM) is an infection caused by Paracoccidioides brasiliensis, and it is a major cause of mortality due to systemic mycoses in Brazil. To date, there have been few reports on the role of miRNAs in the immune response against fungi, especially PCM. The objective of this study was to evaluate the differential expression of miRNAs related to the inflammatory response associated with pulmonary infection by P. brasiliensis. For this purpose, lungs from BALB/c mice, intravenously infected with P. brasiliensis (2.7×107 yeast cells/ml, n = 12) and noninfected BALB/c mice (n = 8), were collected at the 28 and 56 day after infection. The lung parenchyma presented a great number of yeast cells, granulomas, and edema at 28 days and a framework of resolution of the inflammatory process after 56 days. The mRNAs gata-3, ror-γt, foxp3, and IL-6 were positively regulated at the moment at the 56 day, while the TGF-β1 mRNA was positively regulated at both moments. The miRNAs 126a-5p, 340-5p, 30b-5p, 19b-3p, 221-3p, 20a-5p, 130a-3p, and 301a-3p, 466k presented the greatest increase in expression levels 28 days after infection, and the miRNAs let-7f-5p, let-7a-5p, 5p-26b, let-7e-5p and 369-3p, 466k presented a greater increase in levels of expression 56 days after infection. This study shows a set of differentially expressed miRNAs possibly involved in the immune response in mice during pulmonary infection by P. brasiliensis.

Paracoccidioidomycosis: Current Perspectives from Brazil

BACKGROUND

This review article summarizes and updates the knowledge on paracoccidioidomycosis. P lutzii and the cryptic species of P. brasiliensis and their geographical distribution in Latin America, explaining the difficulties observed in the serological diagnosis.

OBJECTIVES

Emphasis has been placed on some genetic factors as predisposing condition for paracoccidioidomycosis. Veterinary aspects were focused, showing the wide distribution of infection among animals. The cell-mediated immunity was better characterized, incorporating the recent findings.

METHODS

Serological methods for diagnosis were also compared for their parameters of accuracy, including the analysis of relapse.

RESULTS

Clinical forms have been better classified in order to include the pictures less frequently observesiod.

CONCLUSION

Itraconazole and the trimethoprim-sulfamethoxazole combination was compared regarding efficacy, effectiveness and safety, demonstrating that azole should be the first choice in the treatment of paracoccidioidomycosis.

New Trends in Paracoccidioidomycosis Epidemiology

Paracoccidioidomycosis is a systemic fungal disease occurring in Latin America and more prevalent in South America. The disease is caused by the dimorphic fungus Paracoccidioides spp. whose major hosts are humans and armadillos. The fungus grows in soil and its infection is associated with exposure to the rural environment and to agricultural activities, with a higher risk in coffee and tobacco plantations. Population studies assessing the reactivity to Paracoccidioides spp. antigens by intradermal reaction or serological tests have detected previous subclinical infections in a significant proportion of healthy individuals living in various endemic countries. Paracoccidioidomycosis-disease is manifested by a small minority of infected individuals. The risk of developing the disease and its type of clinical form are related to the personal and life style characteristics of infected individuals, including genetic background, age, sex, ethnicity, smoking habit, alcohol drinking, and eventual cellular immunosuppression. Brazil, Colombia, Venezuela, Argentina, and Ecuador have endemic areas that had already been defined in the 20th century. The incidence of paracoccidioidomycosis can be altered by climate phenomena and mainly by human migration and occupation of poorly explored territories. In Brazil, the endemy tends to expand towards the North and Center-West around the Amazon Region.

EPIDEMIOLOGY OF PARACOCCIDIOIDOMYCOSIS

The epidemiological characteristics of paracoccidioidomycosis were reviewed and updated. The new endemic areas in Brazil were discussed in the section regarding the geographic distribution of the mycosis. Subclinical infection with Paracoccidioides brasiliensis was discussed on the basis of skin test surveys with antigens of the fungus, seroepidemiological studies, and disease cases outside Latin America. Large case series permitted a comparison of the prevalence of the mycosis in different regions, its estimated incidence and risk factors for the development of the disease. Aspects modulating the expression of the clinical forms of paracoccidioidomycosis are also presented. This review also deals with diseases associated with the mycosis, opportunistic paracoccidioidomycosis, lethality, mortality and infection and disease in animals.

Phenotypic and functional evaluations of peripheral blood monocytes from chronic-form paracoccidioidomycosis patients before and after treatment

BACKGROUND

Paracoccidioidomycosis (PCM) is systemic mycosis caused by the thermal dimorphic fungus of genus Paracoccidioides, leading to either acute/subacute (AF) or chronic (CF) clinical forms. Numerous CF patients after treatment exhibit sequels, such as pulmonary and adrenal fibrosis. Monocytes are cells that are involved in the inflammatory response during active infection as well as in the fibrogenesis. These cells comprise a heterogeneous population with distinct phenotypic and functional activities. The scope of this study was to identify changes regarding functional and phenotypical aspects in monocytes comparing CF PCM patients on antifungal treatment versus non-treated patients (PMC-p).

METHODS

Twenty-three CF PCM composed of 11 non-treated patients (NTG) and 12 patients in apparent cure (ACG) were studied. Sixteen healthy individuals were used as control group (CG). Monocyte subsets were determined by immunophenotyping based on CD14 and CD16 expression. Cellular function was measured in vitro with and without stimulation with lipopolysaccharide (LPS) and P. brasiliensis exoantigen (PbAg) for 24 hours. Independent samples were compared using unpaired t tests, dependent samples were analyzed by paired t-test. Groups of more than two independent samples were analyzed using an ANOVA, with Tukey's post-test. Significance was set up at p <0.05.

RESULTS

Our results showed high counts of peripheral blood CD14+CD16+ and CD14+CD16++ monocytes in untreated PCM-p accompanied by intense production of pro-inflammatory cytokines (IL-1β and TNF-α) and profibrotic growth factors (TGF-β1 and bFGF) by monocytes challenged with P. brasiliensis antigens. After the introduction of antifungal therapy, the counts of CD14+CD16+ cells returned to baseline while CD14+CD16++ counts remained high. Interestingly, counts of CD14+CD16++ monocytes remained elevated even 52 ± 7 months after successful antifungal treatment. Furthermore, the ACG-patients showed preserved pro-inflammatory activity in the presence of specific antigen stimuli and high spontaneous production of TNF-α by monocytes.

CONCLUSIONS

Infection with Paracoccidioides leads to initiation of a specific proinflammatory response by monocytes of PCM-p during active disease and in the apparent cure. A profibrotic profile by monocytes was observed only at admission. Furthermore, PCM-p with apparent cure showed high spontaneous production of TNF-α and high counts of CD14+CD16++ monocytes, probably induced by hypoxia duo to fibrotic sequelae.

Prevalence of paracoccidioidomycosis infection by intradermal reaction in rural areas in Alfenas, Minas Gerais, Brazil

This study aimed to estimate the prevalence of paracoccidioidal infection by intradermal reaction (Delayed-Type Hypersensitivity, DTH) to Paracoccidioides brasiliensis in rural areas in Alfenas, Southern Minas Gerais (MG) State, Brazil, and to assess risk factors (gender, occupation, age, alcohol intake and smoking) associated with infection. We conducted a population-based cross-sectional study using intradermal tests with gp 43 paracoccidioidin in 542 participants, who were previously contacted by local health agents and so spontaneously attended the test. Participants underwent an interview by filling out a registration form with epidemiological data and were tested with an intradermal administration of 0.1 mL of paracoccidioidin in the left forearm. The test was read 48 hours after injection and was considered positive if induration was greater than or equal to 5 mm. Out of 542 participants, 46.67% were positive to the skin test. Prevalence increased in accordance with an increase of age. There was statistical significance only for males. Occupation, alcohol intake and smoking habits were not significantly associated with the risk of paracoccidioidomycosis infection. There is relevance of paracoccidioidomycosis infection in such rural areas, which suggests that further epidemiological and clinical studies on this mycosis should be done in the southern part of Minas Gerais State.

Decreasing prevalence of the acute/subacute clinical form of paracoccidioidomycosis in Mato Grosso do Sul State, Brazil

With the objective to evaluate the behavior of paracoccidioidomycosis in the last three decades, clinical and epidemiological data of 595 patients admitted to clinical services of the Federal University of Mato Grosso do Sul from 1980 to 2009 were investigated. Gender, age distribution, clinical form, comorbidity with tuberculosis or AIDS, and mortality were compared by decades of clinical admission. It was shown that during the three decades there was a decrease in women percentage, and the same manner occurred a reduction in participants in the age group of 20 to 39 years. Moreover, the acute/subacute forms have been diminished in the period. These fluctuations are closely related and can be simultaneously analyzed. Increased AIDS co-infection prevalence from the first to the second decade was also revealed, coinciding with the appearance of the retroviral epidemic and stabilizing during the third decade. No change in the tuberculosis co-infection rate was observed (overall = 6.9%). It reinforces the importance of this co-morbidity. The overall mortality rate remained steady at 6.7%, not varying significantly from one decade to another. The persistent mortality rate calls attention to the importance of this neglected disease.