Elderly patients in general have a lower baseline body temperature than younger patients. Consequently, it makes sense to redefine the definition of what constitutes a "fever" in the elderly. Rather than using the typical oral temperature cutoff of 38o C (100.4o F) for defining a fever, instead consider using 37.2o C (99o F). Redefining fever in this way increases the sensitivity for detecting bacterial infections from 40% to 83% while retaining an 89% specificity.
References
CaterinoJM. Evaluation and management of geriatric infections in the emergency department. Emerg Med Clin N Am 2008;26:319-343.
