Mycobacterium celatum Misdiagnosed as Mycobacterium tuberculosis: Case Report and Review of LiteratureZainah, Hadeel MD*; Toama, Wael MD*; Samuel, Linoj MD†; Alhelo, Sara Chamas MD*; Stephan, Waseem MD*; Tibbetts, Robert J. MD†Infectious Diseases in Clinical Practice: July 2014 - Volume 22 - Issue 4 - p e52–e54 doi: 10.1097/IPC.0b013e3182a01f4d Case Reports Abstract Author Information Abstract: Mycobacterium celatum has been shown to cause fatal disease in both immunocompetent and immunocompromised patients. The similarity in symptoms and radiological features between M celatum and M tuberculosis makes it difficult to differentiate between the 2 clinically or based on early laboratory testing. Clinical symptoms include cough, malaise, and weight loss associated with cavitary lesions and pulmonary infiltrates, whereas the initial laboratory testing includes positive acid-fast stain. Identification using nucleic acid amplification testing (NAAT) in the diagnostic process is sensitive; however, cross-reactivity between M celatum and M tuberculosis NAAT leading to diagnostic errors and inappropriate treatment has been reported. We report a case of pulmonary disease caused by M celatum misdiagnosed as M tuberculosis based on NAAT. From the *Infectious Diseases Division, Henry Ford Health System and †Department of Pathology and Microbiology, Henry Ford Hospital, Detroit, MI. Correspondence to: Hadeel Zainah, MD, Henry Ford Health System, 2799 W Grand Blvd, CFP 304, Detroit, MI 48202. E-mail: firstname.lastname@example.org. The authors have no funding or conflicts of interest to disclose. Hadeel Zainah and Wael Toama contributed equally to the manuscript. © 2014 by Lippincott Williams & Wilkins.