Most cases are caused by infection with bacteria. A small number of cases are caused by infection with fungi.
To develop this infection you need to have some bacteria or fungi in the bloodstream. The blood usually does not contain any bacteria or fungi. However, some may get into the blood if you have an infection or wound in another part of the body.
People who inject street drugs may also inject bacteria or fungi into their bloodstream if they use dirty or contaminated needles.
Most bacteria that get into the bloodstream are killed by the immune system. However, sometimes some bacteria survive and settle on a heart valve (particularly if the valve is already damaged in some way), or on another section of the endocardium. Once a small focus of infection develops in the endocardium it is difficult for the immune system to clear it.
In time, small clumps of material called vegetations may develop on infected valves. The vegetations contain bacteria or fungi, small blood clots, and other 'debris' from the infection. The vegetations may prevent affected valves from opening and closing properly. The infection can also damage affected valves, and may spread to other areas of the endocardium or heart tissue. Fragments of the vegetations may also break off and travel in the bloodstream to other parts of the body.
To develop this infection you need to have some bacteria or fungi in the bloodstream. The blood usually does not contain any bacteria or fungi. However, some may get into the blood if you have an infection or wound in another part of the body.
People who inject street drugs may also inject bacteria or fungi into their bloodstream if they use dirty or contaminated needles.
Most bacteria that get into the bloodstream are killed by the immune system. However, sometimes some bacteria survive and settle on a heart valve (particularly if the valve is already damaged in some way), or on another section of the endocardium. Once a small focus of infection develops in the endocardium it is difficult for the immune system to clear it.
In time, small clumps of material called vegetations may develop on infected valves. The vegetations contain bacteria or fungi, small blood clots, and other 'debris' from the infection. The vegetations may prevent affected valves from opening and closing properly. The infection can also damage affected valves, and may spread to other areas of the endocardium or heart tissue. Fragments of the vegetations may also break off and travel in the bloodstream to other parts of the body.
No comments:
Post a Comment