Paraneoplastic non-bacterial thrombotic endocarditis in a KRAS mutant pulmonary adenocarcinoma

Marantic endocarditis, also known as Nonbacterial Thrombotic Endocarditis (NBTE), is a rare and complex disease which challenges clinicians and researchers alike due to its multifactorial aetiology, diverse clinical presentations, and limited available treatment options. Here we report a case of marantic endocarditis with cerebral, renal and peripheral vascular infarctions in a 43-years-old lady with a KRAS G12C mutant adenocarcinoma of the lung who presented with a left sided 7 th CN palsy, left upper and lower limb hemiplegia, complete aphasia and fixed right gaze palsy. Initial imaging showed findings suggestive of a thrombotic CVA and a thrombectomy was carried out. She subsequently suffered a series of thromboembolic phenomena including several Janeway lesions and splinter haemorrhages, right lower lobe lung infarction, right renal infarction and multiple bilateral cerebral infarctions. Infective endocarditis was suspected and TTE (transthoracic echocardiogram) showed aortic valve vegetations. However, serial blood cultures were negative. An aortic valve replacement was carried out which confirmed NBTE. She was later started on Sotorasib in an attempt to offer palliative control of her pulmonary adenocarcinoma.