septicemia
Meaning of septicemia: An older word for bloodstream infection, largely retired because the danger comes from the body's reaction rather than the bacteria alone.
Definition of septicemia
Septicemia is the presence of bacteria multiplying in the bloodstream together with the severe illness that follows. Bacteria enter from a focus of infection elsewhere, such as the lungs, the urine or the skin, and the body mounts a whole body reaction that can drop blood pressure and injure organs. Current practice splits the idea into bacteremia, bacteria in blood, and sepsis, the dangerous response.
What actually causes the harm?
The damage is not done by the bacteria alone. Fragments of the bacterial surface trigger a flood of immune signaling that spreads far beyond the original site. Blood vessels widen and leak, so pressure falls and fluid seeps into tissue. Clotting switches on across small vessels at the same time as clotting factors are used up, producing tiny clots and bleeding together. Organs starved of blood flow start to fail, the kidneys and lungs often first. That cascade, rather than the number of bacteria in the blood, is what makes the illness lethal.
How do the terms relate?
| Term | Means | Status |
|---|---|---|
| Bacteremia | Bacteria present in the blood | A laboratory finding, not always an illness |
| Sepsis | Organ dysfunction caused by the response to infection | The current clinical term |
| Septic shock | Sepsis with pressure that stays low despite fluid | The most severe form |
| Septicemia | Bacteria in blood plus severe illness | Older, retired as imprecise |
The older word blurred two separate things, which is why it was split apart. Brief bacteremia can follow something as ordinary as vigorous tooth brushing and clears with no consequence, while sepsis can kill even when no organism is ever grown from a blood sample.
What does it look like?
Fever and shaking chills are typical, but temperature can fall instead, particularly in older or frail people. Breathing and heart rate speed up, blood pressure drifts down, and confusion or unusual drowsiness is common and easily missed. Urine output falls. Skin may be flushed and warm early, then mottled and cold as the circulation fails. The picture builds over hours, which is why how quickly it is recognized dominates the outcome.
Is it the same as blood poisoning?
Blood poisoning is the everyday phrase for the same idea and carries no technical meaning of its own. Toxemia is sometimes offered as a synonym but properly means toxins circulating in blood, and in obstetric writing it was once the name for an entirely different condition of pregnancy.
Also known as
Used in a sentence
The discharge summary used the older term septicemia for what the notes recorded as sepsis from a urinary source.
Good to know
Septicemia has largely been replaced by sepsis and bacteremia because the two are not the same thing: bacteria can appear briefly in blood without illness, and sepsis can be fatal even when blood cultures grow nothing.
Word origin
Where “septicemia” comes from
From the Greek sepsis, meaning rotting or putrefaction, and haima, meaning blood.