SCIENTIFIC CONTRIBUTIONS TO UNDERSTANDING PYOMETRA IN DOGS: from etiopathogenesis to therapeutic efficacy

• Grant number: 24/20711-3
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2025
• End date: July 31, 2027
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Camila Infantosi Vannucchi
• Grantee: Camila Infantosi Vannucchi
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The objectives of this study are: (1) To contribute to the elucidation of the etiological and pathogenic pathways for the onset of pyometra in female dogs. Specifically, we intend to: (a) Evaluate the in situ expression of enzymes of the steroidogenic cascade (17-hydroxylase, 17,20-lyase, 5-reductase, 3-beta-hydroxysteroid dehydrogenase, aromatase, 21-hydroxylase and 17-HSD) in the uterus of bitches with pyometra, compared with bitches in diestrus, without uterine disease, (b) Evaluate the main bacterial sources causing pyometra in bitches, (c) Correlate the microbiota of the urinary, vulvovaginal, oral and fecal tracts with the uterine microbiota in bitches with pyometra, in order to identify the possibility of cross-contamination, (d) Analyze and identify the in situ metabolic pathways involved in the pathogenesis of pyometra. (2) To contribute to the accuracy of establishing a definitive diagnosis of pyometra and differential diagnosis for other uterine conditions. Specifically, we intend to identify a possible metabolic marker in order to achieve an accurate differential diagnosis for each uterine condition: pyometra, endometritis, mucometra, in comparison to diestrus. (3) To contribute to establishing the greatest possible efficiency for alternative drug treatment to the therapeutic surgical procedure. Specifically, we intend to: (a) Analyze serum levels of acute phase proteins (CRP, haptoglobin and SAA) in bitches with pyometra and throughout different drug treatment protocols (aglepristone alone or in combination with cloprostenol), (b) Evaluate and correlate bacterial sensitivity and resistance to antimicrobials according to the origin of contamination in pyometra in bitches. To address the different objectives of this study, four separate experiments will be performed: Experiment 1 - Study of the in situ expression of steroidogenic enzymes in the uterus of bitches with cystic endometrial hyperplasia-pyometra syndrome, Experiment 2 - Evaluation of the origin, cross-contamination and main bacteriological agents involved in pyometra in bitches, Experiment 3 - In situ metabolomic analysis of uterine affections in bitches and Experiment 4 - Systemic inflammatory effect of Cystic Endometrial Hyperplasia-Pyometra syndrome and drug treatment in bitches. (AU)