LIBMAN-SACKS ENDOCARDITIS AS THE INITIAL PRESENTATION OF METASTATIC GASTRIC ADENOCARCINOMA

Abstract

TOPIC: Cardiovascular Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: Nonbacterial thrombotic endocarditis (NBTE), "marantic", or "Libman-Sacks" endocarditis is a rare entity describing endocarditis that is non-infectious and usually secondary to advanced malignancy, systemic lupus erythematosus (SLE), or anti-phospholipid antibody syndrome. NBTE usually is found on autopsy, however some patients are diagnosed antemortem. If clinical signs and symptoms are suggestive, a high index of suspicion is needed to diagnosis NBTE. We present a case of endocarditis of unclear etiology that is later determined to be NBTE as the initial manifestation of metastatic gastric adenocarcinoma. CASE PRESENTATION: 63-year-old female with past medical history of recently diagnosed pulmonary embolism (PE) and multivessel deep vein thromboses (DVT's) on apixaban presented with dyspnea and chest tightness. She was found to have macrocytic anemia, bilateral pleural effusions, extensive lymphadenopathy, and splenic infarcts. Transesophageal echocardiogram showed severe mitral regurgitation with two large mitral valve vegetations suggestive of Libman-Sacks endocarditis. Four sets of blood cultures had no growth during the hospitalization, and other atypical causes of infectious endocarditis were ruled out. Rheumatological work-up was nonrevealing including SLE and anti-phospholipid antibody syndrome. Thoracentesis of right and left pleural effusions demonstrated metastatic adenocarcinoma, likely secondary to an upper gastrointestinal source. An esophagogastroduodenoscopy (EGD) was performed which showed an ulcerated lesion in the body of the stomach that was biopsied and showed poorly differentiated adenocarcinoma with signet ring cell features. Her hospital course was complicated by recurrent pleural effusions and clinical deterioration. Patient was subsequently transitioned to comfort measures and passed away shortly after. DISCUSSION: In most cases of nonbacterial thrombotic endocarditis, patients have a known pre-existing disease process such as SLE or malignancy to lead to a suspicion of NBTE. In this case, extensive investigation eventually led to the discovery of metastatic gastric cancer and the correct diagnosis of NBTE. Infectious causes, including atypical organisms and culture-negative endocarditis, must be ruled out to diagnose NBTE. CONCLUSIONS: When presented with endocarditis without a clear etiology, advanced malignancy must be considered. The correct diagnosis of NBTE is crucial and treatment of NBTE secondary to neoplasm consists of systemic anticoagulation as well as treatment directed against the underlying malignancy. REFERENCE #1: Deppisch LM, Fayemi AO. Non-bacterial thrombotic endocarditis: clinicopathologic correlations. Am Heart J 1976; 92:723. REFERENCE #2: el-Shami K, Griffiths E, Streiff M. Nonbacterial thrombotic endocarditis in cancer patients: pathogenesis, diagnosis, and treatment. Oncologist 2007; 12:518. DISCLOSURES: No relevant relationships by Michelle Helbig, source=Web Response No relevant relationships by Prashant Patel, source=Web Response