What is septicemia? Septicemia is a serious bloodstream infection. It occurs when a bacterial infection enters the bloodstream from elsewhere in the body, such as the: skin lungs kidneys bladder This is dangerous because the bacteria and their toxins can be carried through the bloodstream to your entire body. Septicemia can quickly become life threatening, and it must be treated in a hospital. If left untreated, septicemia can progress to sepsis. Sepsis causes inflammation throughout the body. This inflammation can cause blood clots and block oxygen from reaching vital organs, resulting in organ failure. When the inflammation occurs with extremely low blood pressure, it’s called septic shock. Septic shock is fatal in many cases. The Centers for Disease Control and Prevention (CDC) estimates that over 1.7 million adultsTrusted Source in the United States develop sepsis each year. Almost 270,000 (or 15.9 percent) of them may die from the condition. Septicemia causes Septicemia is caused by an infection in another part of your body. Many types of bacteria can lead to septicemia, and the exact source of the infection often can’t be determined. The most common infections that lead to septicemia are: urinary tract infections (UTIs) lung infections, such as pneumonia kidney infections infections in the abdominal area Bacteria from these infections enter the bloodstream and multiply rapidly, causing immediate symptoms.