BACKGROUND: Infective endocarditis (IE) has a high mortality rate, even when treated with appropriate antibiotic therapy and surgical intervention. Right-sided endocarditis is in itself rare, with some studies reporting an incidence of 5–10%. The majority of these cases involve the tricuspid valve, and isolated pulmonary valve endocarditis (PVE) is an extremely rare entity affecting less than 2% of patients with infective endocarditis. Identification and early management are crucial to prevent long-term complications and reduce mortality.

CASE REPORT: We present a patient with a history of essential hypertension and no underlying valvular disease, who underwent dental cleaning and subsequently developed low-grade fever, myalgia, and malaise. This occurred during the flu season, and was initially diagnosed and treated as flu, without any improvement. The patient was later found to be bacteremic with S. mitis, with no identifiable source, and a normal transthoracic echocardiogram (TTE). He was later hospitalized, had a transesophageal echocardiogram, and was found to have a large pulmonic valve vegetation.

CONCLUSIONS: This case presents an interesting and rare finding of endocarditis, isolated to the pulmonic valve, in an otherwise healthy individual with no predisposing risk factors. The lack of peripheral stigmata, as well as an unremarkable initial outpatient TTE, made the diagnosis more difficult. It should also be noted that current guidelines do not specifically address right-sided endocarditis, and do not specify the role of surgical intervention.

Keywords: Endocarditis, Endocarditis, Bacterial, Pulmonary Valve, Dental Prophylaxis, Echocardiography, Streptococcal Infections, Streptococcus mitis