Corynebacterium Striatum Native Valve Endocarditis.

Corynebacterium species are traditionally regarded as harmless commensals, but nondiphtherial strains, such as C. striatum, are now recognised to cause clinically invasive infections, including infective endocarditis. We describe a case of a 25 years old male with a bicuspid aortic valve who presented with persistent fever and was found to have C. striatum bacteremia. Echocardiography revealed multiple vegetations on the aortic valve with aortic regurgitation and an aortic root abscess. Despite being on vancomycin and having therapeutic levels, his fever persisted, so he was switched to linezolid. He developed congestive heart failure, requiring urgent aortic valve replacement with abscess drainage. He recovered well postoperatively and remained stable at one-month follow-up. This case emphasizes the significance of recognizing C. striatum as a rare cause of native valve endocarditis, particularly in young adults with structural heart disease. It highlights the importance of species-level identification, as C. striatum is often multidrug-resistant and has an aggressive course, which directly influences antibiotic selection and timely surgical intervention, thereby improving outcomes.