Abstract
Neisseria is a large genus of bacteria consisting of organisms colonizing mucosal tracts of many animals. Neisseria elongata is a unique member, given that it is a Gram-negative rod, unlike others which are diplococci. Unlike most Neisseria species, N. elongata is catalase-negative and Superoxol-negative. These unique characteristics of N. elongata can make it more difficult to identify. Although considered to be a commensal of the nasopharyngeal tract, this organism has increasingly been identified as a cause of significant disease in humans including endocarditis. We present a case report and literature review of N. elongata causing prosthetic valve endocarditis.