Tropheryma Whipplei Endocarditis: A Diagnosis In Hindsight

ABSTRACT

Description of case We report a case of Tropheryma whipplei endocarditis, a rare cause of bloodculture-negative infective endocarditis (BCNIE). Due to its rarity and lack of availability of diagnostic tests in district hospitals, the diagnosis remains challenging. The objective of this case report is to increase physician awareness of this pathogen. A 61-year-old man presented to the Emergency Department with central chest pain at rest. A 12-lead ECG demonstrated ST- segment depression in V4-V6 leads, and his serial troponin levels were raised. He was commenced on treatment for acute coronary syndrome and transferred to the Coronary Care Unit. An echocardiogram showed a 15mm x 15mm vegetation in the aortic valve with mild aortic regurgitation. His initial microbiology workup, which included two sets of blood cultures (pre-antibiotics), MRSA screen & COVID-19 PCR, was negative. He was transferred to a cardiothoracic centre four days later. Pre-operative CT coronary angiogram showed severe three vessel coronary artery disease. He underwent triple coronary artery by-pass grafts and tissue aortic valve replacement. During early post-op recovery, he had fever episodes and an elevated C-reactive protein of 280 mg/L but normal white cell counts. He was treated with intravenous Tazocin for hospital-acquired pneumonia and discharged on doxycycline. Two weeks post-discharge, he had a positive 16S/18S PCR for Tropheryma whipplei on molecular analysis of the aortic valve. He was treated for Whipples endocarditis with a 4-week course of IV Ceftriaxone, followed by a 12-month course of oral Cotrimoxazole. The patient has reported doing well since the surgery. Discussion(s) Molecular assay with PCR of the heart valve is the mainstay of diagnosing Whipple's endocarditis. There have been 5 previously reported cases of Whipple's endocarditis in the United Kingdom in our knowledge. It is likely under-reported because of a reliance on tissue diagnosis. Preceding intestinal manifestations and arthralgia should raise its clinical suspicion for timely workup. Physician awareness of Whipple's Endocarditis is paramount in investigating for this pathogen.