Therapeutic Response in Adult Patients with Nonsevere Chronic Paracoccidioidomycosis Treated with Sulfamethoxazole-Trimethoprim: A Retrospective Study

Paracoccidioidomycosis: Current Status and Future Trends

Paracoccidioidomycosis (PCM), initially reported in 1908 in the city of São Paulo, Brazil, by Adolpho Lutz, is primarily a systemic and neglected tropical mycosis that may affect individuals with certain risk factors around Latin America, especially Brazil. Paracoccidioides brasiliensis sensu stricto, a classical thermodimorphic fungus associated with PCM, was long considered to represent a monotypic taxon. However, advances in molecular taxonomy revealed several cryptic species, including Paracoccidioides americana, P. restrepiensis, P. venezuelensis, and P. lutzii, that show a preference for skin and mucous membranes, lymph nodes, and respiratory organs but can also affect many other organs. The classical diagnosis of PCM benefits from direct microscopy culture-based, biochemical, and immunological assays in a general microbiology laboratory practice providing a generic identification of the agents. However, molecular assays should be employed to identify Paracoccidioides isolates to the species level, data that would be complemented by epidemiological investigations. From a clinical perspective, all probable and confirmed cases should be treated. The choice of treatment and its duration must be considered, along with the affected organs, process severity, history of previous treatment failure, possibility of administering oral medication, associated diseases, pregnancy, and patient compliance with the proposed treatment regimen. Nevertheless, even after appropriate treatment, there may be relapses, which generally occur 5 years after the apparent cure following treatment, and also, the mycosis may be confused with other diseases. This review provides a comprehensive and critical overview of the immunopathology, laboratory diagnosis, clinical aspects, and current treatment of PCM, highlighting current issues in the identification, treatment, and patient follow-up in light of recent Paracoccidioides species taxonomic developments.

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.

Puzzling paracoccidioidomycosis: Factors associated with the severity of Paracoccidioides lutzii infections

OBJECTIVES

Historically, the Brazilian Central-West region has had high numbers of paracoccidioidomycosis (PCM) cases caused by the dimorphic fungus Paracoccidioides lutzii.

METHODS

This epidemiological, observational, analytical, cross-sectional study was performed to investigate the clinical and laboratory data of 44 PCM patients with a culture-proven P. lutzii infection. All patients were referred to the Systemic Mycosis Center, Júlio Muller University Hospital, Cuiabá, Brazil, during January 2017 to March 2020. The neutrophil to lymphocyte ratio (NLR) was calculated and dichotomized by its median value to include in the identification of factors associated with severity.

RESULTS

At admission, 13 (31.7%) patients showed the disseminated multifocal chronic form of PCM and 16 (36.4%) patients met the clinical severity criteria. Treatment prescribed on admission did not follow the recommendations of the Brazilian Guideline for the Clinical Management of Paracoccidioidomycosis in 26% of the severe PCM cases (prevalence ratio 0.26, 95% confidence interval 0.14-0.49; P < 0.0001). Patients with severe PCM had a higher NLR that was greater than the median (≥4.11).

CONCLUSIONS

The NLR biomarker complements the criteria for PCM severity. Applying the low-cost NLR test can greatly increase the diagnostic sensitivity when screening patients for PCM and contribute to better control of the disease, management of complications, and therapeutic strategies.

Clinical and epidemiological features of paracoccidioidomycosis due to Paracoccidioides lutzii

BACKGROUND

The fungus Paracoccidioides lutzii was recently included as a new causative species of paracoccidioidomycosis (PCM) and most cases have been reported from Brazil. According to available epidemiological information, P. lutzii is concentrated in the Middle-West region in Brazil, mainly in the state of Mato Grosso. However, clinical and laboratorial data available on patients infected with P. lutzii remain extremely limited.

METHODOLOGY/MAIN FINDINGS

This work describes the clinical manifestations of 34 patients suffering from PCM caused by P. lutzii, treated along 5 years (2011-2017) at a reference service center for systemic mycoses in Mato Grosso, Brazil. Adult rural workers (men), aged between 28 and 67 predominated. All patients had the chronic form of the disease, and the oral mucosa (n = 19; 55.9%), lymph nodes (n = 23; 67.7%), skin (n = 16; 47.1%) and lung (n = 28; 82.4%) were the most affected sites. Alcohol intake (n = 19; 55.9%) and smoking (n = 29; 85.3%) were frequent habits among the patients. No patient suffered from any other life-threatening disease, such as tuberculosis, cancer or other inflammatory or infectious parasitic diseases. The positivity in culture examination (97.1%) was higher than that found for the direct mycological examination (88.2%). Particularly, one patient presented fungemia at diagnosis, which lead to his death. The time elapsed between the initial symptoms and the initiation of treatment of PCM caused by P. lutzii was 19.7 (31.5) months, with most patients diagnosed 7 months after the symptoms' onset.

CONCLUSIONS/SIGNIFICANCE

Compared with the classical clinical-epidemiological profile of PCM caused by P. brasiliensis, the results of this descriptive study did not show significant clinical or epidemiological differences that could be attributed to the species P. lutzii. Future studies may confirm or refute the existence of clinical differences between the two fungal species.