Background/ purpose: Atypical presentation of acute infections, is a well-known phenomenon in older people. It is extensively recognized in the literature but lacks sufficient attention in recent clinical research. Reaching a disease - specific diagnosis in those with subtle, nonspecific , or atypical presentations is a major challenge. The aim of this study was to report the prevalence of different presentations of acute infections among hospitalized elderly patients, and the factors associated with atypical presentation. Methods: a retrospective medical records review of 220 patients diagnosed with acute infection. The presenting symptoms for each type of infection were reported. Data regarding medical comorbidities, cognition, frailty, and functional status were obtained. Factors associa ted with the atypical presentation were evaluated. Results: Urinary tract infections and community -acquired pneumonia accounted for 44.5% and 25.5% infections, respectively. The patients presented with atypical symptoms in absence of classical symptoms rep resented 35.5% of the cases. 64.5% of the participants had an absent febrile response. Decreased oral intake was the most prevalent atypical complaint followed by unexplained new-onset functional decline. Dementia and frailty were independent predictors for atypical presentations. Conclusions: Older adults present acute infections differently. Many common infections present as delirium, new functional decline, new or worsened incontinence [urine, fecal], anorexia, or falls, especially in patients with dementia and frailty. Fever is usually absent in the elderly with acute infections. Moreover, infections in the elderly may present as an exacerbation of chronic stable medical illness e.g. congestive heart failure or diabetes. The in - hospital mortality is higher among those having atypical presentation