Abstract
Sepsis is a heterogenous and imprecise syndrome that includes multiple phenotypes, some of which are amenable to specific therapies. Developing new therapies for sepsis will require focusing on subsets of patients. Key to improving care is evaluating patients for sepsis mimics and treatable diseases whose manifestations lead to a clinical classification of sepsis. Because sepsis is common, it is easy to overlook unusual causes of organ failure and succumb to confirmation bias about the nature of an illness. Careful attention to medical and family histories, focused diagnostic testing, and subspecialty input can help identify potentially treatable diseases masquerading as typical sepsis.