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What is anemia? Anemia happens when your red blood cells are in short supply. Red blood cells carry oxygen from your lungs to all parts of your body, giving you the energy you need for your daily activities. What are the symptoms of anemia? Anemia can cause you to: Look pale Feel tired Have little...

Goodpasture's Syndrome is an uncommon autoimmune disease that affects both the kidneys and the lungs. An autoimmune disease means that the immune system, which usually protects the body from infection, attacks healthy parts of the body by mistake. What causes the disease? The body's immune system...

What is HIV? HIV (human immunodeficiency virus) is a virus that infects and damages your immune system. Your immune system helps your body defend itself against infection and other disease. HIV attacks and destroys the disease-fighting cells of your immune system and leaves your body weak against...