Discussion
The differential diagnosis for aortic valve mass includes papillary fibroelastoma, endocarditis, Lambl’s excrescence. Our case highlights the challenge in diagnosing Whipple’s endocarditis. Our patient presented with TIA from a cardiac embolic cause without arthralgia, the most common symptom of Whipple endocarditis, and no systemic signs of infection such as fever. However, the majority of cases described in the literature reported aortic valve lesions in the absence of fever [6]. Furthermore, it is crucial to recognize that T whipplei  endocarditis differs from classic Whipple disease, which tends to involve multiple organ systems. Our case also highlights the importance of molecular diagnostics in the diagnosis of that T whipplei  endocarditis. Pathologically, our patient’s lesion resembled an Amorphous Cardiac Tumor, which rarely arises in the aortic valve. In fact, there have been four cases of CAT with isolated involvement of the aortic valve [7-10]. Several features made CAT an unlikely diagnosis in our patient. Even though pathogenesis of CAT is poorly understood, a systematic review revealed that 21% of CAT cases were found in patients with end-stage renal disease [11], which our patient did not have. Furthermore, there is a female predominance, and the majority of reported CAT cases involve the left ventricle the mitral valve, with only a few reported cases arising from the aortic valve [12]. A histopathologic diagnosis of T whipplei endocarditis, however can be made with periodic acid-Schiff (PAS) staining. Although more commonly performed on duodenal biopsies in the diagnosis of classical whipple’s disease, PAS-positive macrophages from an extracted valvular lesion has been reported [6,13,14]. For T whipplei endocarditis, molecular analysis with 16S rRNA PCR following surgical resection of the valvular lesion is currently the preferred diagnostic approach. Unfortunately, 16S rRNA amplification from blood specimens is not sensitive [15].