Whipple's endocarditis: a case report of a blood culture-negative endocarditis

Tropheryma whipplei Endocarditis Presenting as Valvulopathy and Multiple Septic Emboli

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.

An unusual presentation of a rare disease: acute upper limb ischemia as the presenting symptom of Whipple's Endocarditis, a case report

BACKGROUND

Whipple's disease is known to cause multiple varied systemic symptoms, and is a well-documented cause of culture-negative endocarditis. Endocarditis secondary to Whipple disease, however, has rarely been known to present primarily as a cause of acute limb ischemia. We describe such a case here.

CASE PRESENTATION

A previously healthy 40 year old man presented to the emergency department with acute-onset right arm paresthesias. On exam, he was found to be tachycardic with a VI/VI systolic ejection murmur. He was diagnosed with critical limb ischemia and severe aortic regurgitation, and echocardiography showed a large mass on his bicuspid aortic valve. Thrombectomy was performed urgently, with aortic valve repair the following day. As blood cultures and valvular tissue culture remained unrevealing, the patient remained on empiric vancomycin and ceftriaxone for culture-negative endocarditis. 16 s rRNA nucleic acid amplification testing (NAAT) of his formalin-fixed, paraffin-embedded valvular tissue detected T. whipplei, after which the patient was transitioned to ceftriaxone and trimethoprim-sulfamethoxazole for a year of therapy. He continues to do clinically well.

CONCLUSIONS

We report an unusual presentation of Whipple endocarditis as an acute upper limb ischemia, absent other classic symptoms of Whipple's disease, and with diagnosis made by 16 s rRNA NAAT of valvular tissue in the setting of culture-negative endocarditis.

Blood Culture-negative Endocarditis Caused by Tropheryma whipplei: Whipple's endocarditis

Case description

A 67-year-old man was admitted with progressive heart failure due to blood culture-negative endocarditis of the aortic valve. Urgent aortic valve replacement was needed. Polymerase chain reaction (PCR) testing of samples of the explanted aortic valve revealed Tropheryma whipplei. The patient received ceftriaxone, followed by long-term co-trimoxazole. Recent arthralgia may have been a diagnostic clue.

Conclusion

Whipple's endocarditis should be considered in patients with arthralgia and blood culture-negative endocarditis (BCNIE).

LEARNING POINTS

Whipple's endocarditis should be considered in patients with symptoms of arthralgia and blood culture-negative endocarditis (BCNIE).Serum polymerase chain reaction is the main diagnostic test.Both physician awareness and multidisciplinary management by regional endocarditis teams are recommended strategies to provide optimal patient care.