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Acne is a skin condition that occurs when your hair follicles become plugged with oil and dead skin cells. Acne usually appears on your face, neck, chest, back and shoulders. Effective treatments are available, but acne can be persistent. The pimples and bumps heal slowly, and when one begins to go away, others seem to Read more…

An ACL injury is the tearing of the anterior cruciate (KROO-she-ate) ligament (ACL) — one of the major ligaments in your knee. ACL injuries most commonly occur during sports that involve sudden stops, jumping or changes in direction — such as basketball, soccer, football, tennis, downhill skiing, volleyball and gymnastics. Many people hear or feel Read more…

Achilles (uh-KILL-eez) tendon rupture is an injury that affects the back of your lower leg. It most commonly occurs in people playing recreational sports. The Achilles tendon is a strong fibrous cord that connects the muscles in the back of your calf to your heel bone. If you overstretch your Achilles tendon, it can tear Read more…

Achilles tendinitis is an overuse injury of the Achilles (uh-KILL-eez) tendon, the band of tissue that connects calf muscles at the back of the lower leg to your heel bone. Achilles tendinitis most commonly occurs in runners who have suddenly increased the intensity or duration of their runs. It’s also common in middle-aged people who Read more…

Achalasia is a rare disorder that makes it difficult for food and liquid to pass into your stomach. Achalasia occurs when the food tube (esophagus) loses the ability to squeeze food down, and the muscular valve between the esophagus and stomach doesn’t fully relax. The reason for these problems is damage to the nerves in Read more…

Acanthosis nigricans is a skin condition characterized by areas of dark, velvety discoloration in body folds and creases. The affected skin can become thickened. Most often, acanthosis nigricans affects your armpits, groin and neck. The skin changes of acanthosis nigricans (ak-an-THOE-sis NIE-grih-kuns) typically occur in people who are obese or have diabetes. Children who develop Read more…

Absence seizures involve brief, sudden lapses of consciousness. They’re more common in children than adults. Someone having an absence seizure may look like he or she is staring into space for a few seconds. This type of seizure usually doesn’t lead to physical injury. Absence seizures usually can be controlled with anti-seizure medications. Some children Read more…

An abdominal aortic aneurysm is an enlarged area in the lower part of the aorta, the major blood vessel that supplies blood to the body. The aorta, about the thickness of a garden hose, runs from your heart through the center of your chest and abdomen. Because the aorta is the body’s main supplier of Read more…