Avian Infective Endocarditis Associated with Vagococcus fluvialis: A Case Report and Literature Review

Area of Science:

• Veterinary Pathology
• Avian Medicine
• Bacteriology

Background:

• Avian infective endocarditis is severe and often diagnosed postmortem due to vague symptoms.
• Existing literature shows poultry are primarily affected, mainly by Gram-positive bacteria.

Purpose of the Study:

• To report the first molecularly confirmed case of valvular endocarditis caused by multidrug-resistant Vagococcus fluvialis in poultry.
• To review bacterial endocarditis in avian species.

Main Methods:

• Examination of five broiler chickens with septicemia and endocarditis-like lesions.
• Identification of bacterial isolates using MALDI-TOF mass spectrometry and 16S rRNA gene sequencing.
• Antimicrobial susceptibility testing and a comprehensive literature review.

Main Results:

• Valvular endocarditis, pericarditis, and multiorgan involvement were observed in affected chickens.
• Isolates were identified as multidrug-resistant Vagococcus fluvialis.
• Literature review confirmed overlapping clinical signs and necropsy findings across avian endocarditis etiologies.

Conclusions:

• Vagococcus fluvialis is a novel etiological agent for avian infective endocarditis.
• Accurate diagnosis is challenging, especially with rare pathogens, emphasizing advanced identification methods.
• Antimicrobial resistance and improved diagnostics are crucial for poultry health surveillance.