Corynebacterium urealyticum: a comprehensive review of an understated organism Nagla Salem,1 Lamyaa Salem,2 Sally Saber,2 Ghada Ismail,2 Martin H Bluth1 1Department of Pathology, Wayne State University School of Medicine, Detroit, MI, USA; 2Department of Clinical and Chemical Pathology, Ain Shams University, Cairo, Egypt Abstract: Corynebacterium urealyticum is a Gram positive, slow-growing, lipophilic, multi-drug resistant, urease positive micro-organism with diphtheroid morphology. It has been reported as an opportunistic nosocomial pathogen and as the cause of a variety of diseases including but not limited to cystitis, pyelonephritis, and bacteremia among others. This review serves to describe C. urealyticum with respect to its history, identification, laboratory investigation, relationship to disease and treatment in order to allow increased familiarity with this organism in clinical disease. Keywords: Corynebacterium urealyticum, cystitis, pyelonephritis, bacteremia, micro-organisms