Infective Endocarditis Caused by Streptococcus sinensis: A Rare but Fatal Infection

We present a case concerning a 65-year-old, previously healthy gentleman who was found to have infective endocarditis after presenting with a four-month history of constitutional symptoms. Blood tests taken in the community showed elevated inflammatory markers and a deterioration in renal function, which prompted his referral for inpatient investigations. Blood cultures and a transesophageal echocardiogram subsequently confirmed native valve endocarditis affecting both the aortic and mitral valves. Infective endocarditis is common in an infectious disease physician's daily practice, but this particular case is notable since the causative agent, Streptococcus sinensis, is an extremely rare viridans group Streptococcus, which has been reported only sporadically in other European countries. The patient was started on appropriate anti-microbial treatment and was scheduled for surgery to replace both affected valves. He developed signs and symptoms of congestive heart failure after 10 days of anti-microbial treatment and underwent dual valve replacement surgery. Despite optimal anti-microbial therapy and multiorgan support in a cardiac intensive care unit, the patient passed away two weeks after surgery as a result of ventilator-associated pneumonia.