Introduction
Infective endocarditis (IE) and osteomyelitis are rare and potentially life-threatening infections. Staphylococcus aureus (S. aureus ) is the most common pathogen associated with both osteomyelitis and IE, with a proclivity of infections resulting from methicillin-sensitive strains [1-3]. Concomitant vertebral osteomyelitis and IE have been documented in the literature, but only in about 10% of osteomyelitis cases [4]. In IE, aberrations in valvular structure often contribute to nidus formation. This fosters a bacteria-rich environment that can seed secondary infections throughout the body. Spinal dissemination of endocarditis infections most commonly arise in the lumbar spine, with a minority of cases involving cervical and thoracic vertebrae [1].
Instances of embryological heart remnants contributing to endocarditis have been infrequently documented in the literature. Of those cases, less than 50 involve an embryological remnant of the inferior vena cava, known as the eustachian valve (EV). Persistent EVs occur in approximately 4% of the general population and are generally a benign and incidental finding [5]. In the setting of prolonged bacteremia, intravenous drug use, and indwelling catheters, EV remnants have the potential to facilitate bacterial growth, most commonly with S. aureus [6]. To our knowledge, EV endocarditis has yet to be reported in the presence of thoracic osteomyelitis. In this case, we report a 43-year-old African American male presenting with encephalopathy stemming from treatment-resistant osteomyelitis of the thoracic vertebrae caused by MRSA. Further investigation revealed an elusive nidus of infection stemming from an EV remnant.