What is acne? Acne is a common skin condition that happens when hair follicles under the skin become clogged. Oil and dead skin cells plug the pores, and outbreaks of lesions (often called pimples or zits) can happen. Most often, the outbreaks occur on the face but can also appear on the back, chest, and shoulders. For most people, acne tends to go away by the time they reach their thirties, but some people in their forties and fifties continue to have this skin problem.

What is osteonecrosis? Your bones are made up of living cells that need a blood supply to stay healthy. In osteonecrosis, blood flow to part of a bone is reduced. This causes death of bone tissue, and the bone can eventually break down and the joint will collapse. Osteonecrosis can happen to any bone, but most often it develops in the ends of long bones, such as the: Thigh bone. Upper arm bone. Less often, the bones of the elbows, ankles, feet, wrists, and hands are affected. When the disease involves part of a bone in a joint, it can

What is Marfan syndrome? Marfan syndrome is a genetic disorder that affects the body’s ability to make healthy connective tissue, which supports the bones, muscles, organs, and tissues in your body. The condition can affect different areas of the body, including: Bones, ligaments, tendons, and cartilage. Organs, such as the heart and lungs. Skin.

What is pemphigus? Pemphigus is a rare disease that causes blistering on many parts of the body, including the skin and the inside of the mouth, nose, throat, eyes, and genitals. In pemphigus, the immune system mistakenly attacks cells in the top layer of the skin.

What is scleroderma? Scleroderma is an autoimmune connective tissue and rheumatic disease that causes inflammation in the skin and other areas of the body. This inflammation leads to patches of tight, hard skin. Scleroderma involves many systems in your body. A connective tissue disease is one that affects tissues such as skin, tendons, and cartilage. There are two major types of scleroderma: Localized scleroderma only affects the skin and the structures directly under the skin. Systemic scleroderma, also called systemic sclerosis, affects many systems in the body. This is the more serious type of scleroderma and can damage your blood

What are autoinflammatory diseases? Autoinflammatory diseases refer to problems with the immune system, which usually fights off viruses, bacteria, and infection. The problem causes your immune cells to attack your body by mistake. This can cause swelling that produces fever, rash, joint swelling, or serious buildup of a blood protein in your organs.

What are polymyalgia rheumatica and giant cell arteritis? Polymyalgia rheumatica and giant cell arteritis are closely linked inflammatory disorders. Some people have one of the disorders while others develop both of them. Polymyalgia rheumatica causes muscle pain and stiffness in the shoulders, upper arms, hip area, and sometimes the neck. Giant cell arteritis causes inflammation of arteries, especially those on each side of the head, scalp, and the aorta (the large artery that carries blood from the heart) and its main branches. The main symptoms of this disorder are: Headaches. Scalp tenderness. Jaw pain. Problems with your eyes, which may