ABSTRACT
A 63-year-old man was admitted to the hospital for nausea, vomiting, and right flank pain. He was found to have septic emboli in multiple organs secondary to aortic valve endocarditis. He was started on broad-spectrum antibiotics and underwent valve replacement. Blood cultures from admission were negative, but a blood polymerase chain reaction (PCR) test for fastidious difficult-to-culture pathogens showed a positive result for Tropheryma whipplei. Valve histopathological evaluation confirmed Tropheryma whipplei endocarditis. He was treated with intravenous penicillin followed by oral trimethoprim-sulfamethoxazole. A high index of suspicion for causes of culture-negative endocarditis needs to be maintained when blood cultures are negative despite clear evidence of endocarditis especially with large vegetation sizes and other complications such as septic emboli. Multiple imaging modalities are available to assist with diagnosis including transthoracic and transesophageal echocardiogram as well as cardiac computed tomography. A blood PCR test can identify the implicated pathogen in a more expeditious manner compared to valve histopathological evaluation. Treatment is complex and usually requires surgical intervention and prolonged antimicrobial therapy.
