PL2 probe tests to identify your analytical and clinical sensitivity to species Paracoccidioides lutzii

• Grant number: 23/00501-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2023
• End date: March 31, 2025
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Plinio Trabasso
• Grantee: Danielly Rodrigues Silveira de Freitas
• Host Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Paracoccidioidomycosis is the most prevalent systemic mycosis in Brazil and presents with two fungal species as infectious agents: Paracoccidoides brasiliensis (P. brasiliensis) and Paracoccidioides lutzii (P. lutzii). These strains develop in humid regions, having a tenuous relationship with agricultural activities. In the clinic, its manifestation occurs in two distinct ways: theacute/subacute form and chronic form. In the first, the disease occurs in young patients who were infected a few weeks or months ago andevolution is rapid and systemic, characterized by generalized or localized lymphadenomegaly, accompanied by lesions of the cutaneous and oral mucous membranesand intestinal. On the other hand, the chronic form most often affects adults between 30 and 60 years of age and the lungs are the main affected organs, in addition to lesions in the upper airways and oral mucosa.To perform the diagnosis, there is analysis of biological material directly and identification of the Gp43 antigen through serological tests, however these methods have setbacks that prevent the advance of general and specific information of the disease, mainly related to the species P. lutzii. Therefore, a probe was created to specifically detect this strain with an interest in improving the diagnosis and characterizing its clinical and laboratory varieties.Therefore, this research project aims to collect and test new samples of patients with paracoccidioidomycosis to prove the efficacy of the PL2 probe and improve the analytical and clinical sensitivity data of the PL2 probe. For this, the research participants will have their data from the medical records analyzed. A sample (5 mL) of blood, an oropharynx smear and, when necessary, a smear of vocal cords will be collected. The samples will undergo DNA quantification through appropriate equipment and, later, sequential DILutions of DNA will be performed for LAMP reaction using the PL2 probe for each dilution, determining analytical sensitivity. Finally, for clinical sensitivity, positive tests and negative tests will be quantified, performing sensitivity and positive predictive value calculations.