Background: Tuberculosis is currently the world's leading cause of death arising from a single infectious condition. While T cell mediated immunity is recognized to have a major contribution to tuberculosis activation, the present investigation confirmed that TB was more prevalent among patients with acute myeloid rather than lymphoid leukemia and such association was frequently overlooked. The primary objective of this study is to estimate the diagnostic delay of tuberculosis among patients with acute myeloid leukemia (AML) and compare it to the general population in Qatar. Secondary objective is to study the clinical and epidemiologic characteristics of tuberculosis in patients with AML. Methods: This is a retrospective study of tuberculosis cases diagnosed in subjects with AML during the period from January 2008 till December 2016. Results: Among 215 subjects with AML identified during the study period, 12 (5.58%) received the diagnosis of tuberculosis. The estimated incidence of tuberculosis among AML cases was 7.14 cases per 1000 per year. The mean delay in diagnosis of tuberculosis was 64.2 days (95% CI: 26.8 -101.5) and the median was 45 days (interquartile range; Q1 -Q3, 29.5 -97.5). Prolonged fever was the most common presentation (100% of cases). Parenchymal lung involvement was the most common radiologic abnormality (83.3% of cases). Three patients (25%) died and 8 patients completed 9 to 12 months of anti-tuberculous treatment with clinical and radiological remission. Conclusion: Infections caused by Mycobacterium tuberculosis are not How to cite this paper: El Omri, H., Taha, R., Ibrahim, W., Kassem, N., Szabados, L., El Sabah, H., Abid, F.B., Gamiel, A., Al Khinji, A., Szmeigielski, W., Hasan, S. and Al Hijji, I. (2018