Review ArticlesChlamydia pneumoniae Infections in an Immunocompetent Patient Compared With a Neutropenic Cancer Patient A Case Series and Review of LiteratureAbraham, Abel Mundakakuzhiyil*; Greene, John N. MD, FACP†Author Information From the *College of Medicine, University of South Florida Morsani †H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL. Correspondence to: John N. Greene, MD, FACP, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Dr, FOB-3 Tampa, FL 33612-9497. E-mail: John.Greene@moffitt.org. The authors have no funding or conflicts of interest to disclose. Online date: November 15, 2019 Infectious Diseases in Clinical Practice: January 2020 - Volume 28 - Issue 1 - p 1-6 doi: 10.1097/IPC.0000000000000789 Buy Metrics AbstractIn Brief Chlamydia pneumoniae, an uncommon cause of respiratory tract infections, is difficult to diagnose in most patients. Its signs, symptoms, laboratory values, and imaging are nonspecific, and historically, culture or serology was required to implicate the organism. Because many physicians begin treatment of bacterial pneumonia with antibiotics ineffective against C. pneumoniae, cases of atypical pneumonia caused by this organism require greater time, resources, and analysis before positive diagnoses and the start of effective treatment. However, the emergence and widespread use of polymerase chain reaction have led to quicker recognition of respiratory tract infections caused by C. pneumoniae. This is especially relevant for immunosuppressed cancer patients, who must be quickly treated to prevent the development of serious complications. This article reviewed the limited literature regarding C. pneumoniae and immunosuppressed cancer patients, concluding that prompt diagnosis and standard recommended treatment of C. pneumoniae will provide favorable outcomes. Respiratory tract infections caused by Chlamydia pneumoniae are non-specifi c and diffi cult to diagnose. But as polymerase chain reaction use increases, C. pneumonia is becoming more quickly recognized. In immunosuppressed patients, such as cancer patients, this allows for quicker treatment and minimization of complications. This paper reviews the literature regarding C. pneumoniae in immunosuppressed cancer patients, concluding that prompt diagnosis and standard recommended treatment for C. pneumoniae will provide favorable outcomes. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.