Septic and toxic shock are complications of infection, rather than representing an infection in themselves. Severe bacterial infection causes a multitude of effects in the body. The body attempts to fight the infection, but sometimes the immune response is amplified to an abnormal degree. Harmful products can be released by different parts of the body’s immune system (white blood cells, blood vessels, the liver) which lead in turn to fever, low blood pressure, and failure of several of the body’s main organ systems. This is known as “septic shock” and can occur in response to any bacterial infection that is severe. Products released by the bacteria themselves may also contribute to this cascade of events. Low blood pressure means that vital organs such as the kidney, liver, and brain do not receive enough blood, hence urine flow may stop, and the patient may become drowsy or confused. The lungs may also become inflamed, even if they are not directly involved in the infection. This is known as “shock lung” or ARDS (respiratory distress syndrome), and prevents oxygen from reaching the rest of the body. This will have obvious further consequences for vital organ systems, including the heart, lung, brain, kidney and liver. Blood clotting may also become abnormal, and bruising or bleeding may be seen.