Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Neonates and children are particularly prone to sepsis owing to their immature immune systems. Affected individuals may present with localizing symptoms specific to a source of infection but may often complain of nonspecific systemic symptoms, such as confusion, lethargy, and fever. Diagnosis is based on history, exam, laboratory testing, and imaging studies. A high index of suspicion, rapid diagnosis, and clinical intervention with appropriate therapy are mandatory to achieve favorable outcomes.
Last updated: Sep 24, 2026
The host’s ability to resist direct damage by the pathogen and immune system Immune system The body’s defense mechanism against foreign organisms or substances and deviant native cells. It includes the humoral immune response and the cell-mediated response and consists of a complex of interrelated cellular, molecular, and genetic components. Primary Lymphatic Organs response determines if an infection can be controlled or will result in sepsis Sepsis Systemic inflammatory response syndrome with a proven or suspected infectious etiology. When sepsis is associated with organ dysfunction distant from the site of infection, it is called severe sepsis. When sepsis is accompanied by hypotension despite adequate fluid infusion, it is called septic shock. Sepsis and Septic Shock.
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