septicemia

Septicemia is a serious medical condition in which infection-causing microorganisms enter the bloodstream and provoke a systemic inflammatory response. In modern terminology, the term septicemia is used less often; clinicians distinguish bloodstream infection, sepsis, and septic shock. Septicemia can lead to sepsis when the body's response to infection causes organ dysfunction.

Most septicemias are bacterial, including both gram-positive and gram-negative organisms; fungi such as Candida can also be involved, while viral bloodstream infections are less common. Primary infection sources include the lungs, urinary tract, abdomen, skin and soft tissues, and infected medical devices such as catheters or prosthetic joints. Risk factors include advanced age, immunosuppression, chronic diseases, and invasive procedures.

Common symptoms include fever or hypothermia, chills, rapid heart rate, rapid breathing, confusion, and, in severe cases, low blood pressure and reduced urine output. Laboratory findings often show elevated inflammatory markers and, in septic shock, signs of organ dysfunction. Blood cultures are important for identifying the causative organism.

Treatment requires urgent medical attention. Immediate broad-spectrum intravenous antibiotics are started, then tailored based on culture results. Aggressive fluid resuscitation with isotonic crystalloids is standard, and vasopressors may be needed for persistent hypotension. Source control, such as drainage of an infection or removal of an infected device, is essential. Supportive care, including intensive care when needed, helps manage organ dysfunction.

Prognosis varies with age, comorbidities, and the timeliness of treatment; septic shock carries higher mortality. Prevention focuses on infection control, careful management of invasive devices, vaccination, and prompt treatment of infections.