Nocardiosis is an infection caused by bacteria called Nocardia asteroides. It usually starts in the lungs and may spread to the skin and brain.

What is going on in the body?

Nocardia asteroides, the bacteria that causes nocardiosis, is found worldwide in the natural environment. The bacteria usually live in decaying matter in the soil. A person usually gets nocardiosis after inhaling the organisms in dust. The bacteria can also enter a person's body through puncture wounds or abrasions of the skin which are contaminated by soil.

Nocardiosis begins as a lung infection. It can spread through the bloodstream to cause abscesses, or pockets of pus, in many parts of the body. Abscesses can develop in the brain, kidney, liver, bone, and beneath the skin

What are the causes and risks of the infection?

The bacterium Nocardia asteroides causes nocardiosis. Chronically ill people and those receiving medications that suppress the immune system are at increased risk for this condition. It is more common in men.