'From Gut to Heart': A rare case of Salmonella Typhimurium Bacteremia and native valve endocarditis

Background: Salmonella species are very rarely associated with infective endocarditis, accounting for less than 0.01-2.9 % of total bacterial endocarditis cases. Since 1976, there have less than 90 reported cases of non-Typhoidal Salmonella bacteremia and endocarditis.

Case presentation: We present the case of a 57-year-old homeless man with a past medical history significant only for polysubstance abuse. He presented to the emergency department with a 3-day history of severe, non-bloody diarrhea, nausea, chills, and oliguria. Due to the patient's history of substance use, screening laboratory tests were conducted and were positive for rapid plasma reagin, treponemal antibodies, and hepatitis C. For the profuse diarrhea and severe volume loss, C. difficile, stool white blood cells and stool ova and parasites were ordered but were ultimately negative. Both sets of blood cultures were found to be positive for Salmonella Typhimurium bacteremia. Further workup with transthoracic and transesophageal echocardiogram displayed small mobile masses attached to the aortic surface of the right and non-coronary cusps, confirming endocarditis on the aortic valve. Treatment included penicillin-G once a week for 3 weeks for latent syphilis and ceftriaxone and levofloxacin for bacteremia and endocarditis.

Conclusions: Patients with Salmonella typically present early with gastrointestinal symptoms, but clinicians should consider cardiovascular imaging if blood cultures are found to be positive in order to potentially identify and promptly treat highly fatal Salmonella endocarditis.