In-depth

Anaphylaxis

Anaphylaxis is the most serious type of allergic reaction. It often occurs rapidly after exposure to an allergen and may be life-threatening.

Atrioventricular canal defect

Atrioventricular canal defect is a congenital heart defect involving a hole in the center of the heart and abnormal valves between the heart's chambers.

Bee stings

Bee stings — Comprehensive overview covers prevention, treatment of bee stings.

Chilblains

How to identify, treat and prevent chilblains.

Complex regional pain syndrome

Complex regional pain syndrome is a chronic, painful disease that typically affects an arm or leg that was recently injured or infected.

Dermatitis

Dermatitis, an inflammation of the skin, can have many causes and occur in many forms. Here's how to recognize and treat this itchy skin disorder.

Dermatographia

Dermatographia is a condition characterized by raised, red lines where you've scratched your skin. It may be due to allergies.

Dilated cardiomyopathy

Enlarged heart

Enlarged heart is often a sign of a serious heart condition. Find out causes and treatments for enlarged heart.

Factor V Leiden

Factor V Leiden is an inherited disorder that results in an increased risk of blood clots. There's no cure, but blood-thinning medication can lower the risk of clotting.

Glomerulonephritis

Glomerulonephritis affects your kidneys' filtering function. Complications include high blood pressure, protein in the urine (proteinuria) and kidney failure.

Heart disease

Heart disease, usually thought of as blockages in the arteries that can cause a heart attack, can describe any medical condition affecting your heart.

Heart failure

Heart failure means your heart can't efficiently pump blood throughout your body. Medications, and sometimes devices or surgery, can help you manage this condition.

Heart murmurs

This whooshing sound in your heart is usually harmless, but in some cases heart murmurs can alert your doctor to specific heart conditions.

Hemolytic uremic syndrome (HUS)

Hemolytic uremic syndrome is an uncommon condition that can cause life-threatening kidney failure, especially for children and older adults.

Hives and angioedema

Hives and angioedema — Comprehensive overview covers symptoms, causes, treatment of these common allergic disorders.

IgA nephropathy (Berger's disease)

IgA nephropathy (Berger's disease) is a kidney disorder caused by abnormal deposits of immunoglobulin A (IgA) inside your kidneys.

Lymphedema

Mitral valve stenosis

Mixed connective tissue disease

Mixed connective tissue disease features signs and symptoms of a combination of disorders — primarily lupus, scleroderma and polymyositis.

Nephrotic syndrome

Usually caused by damage to tiny blood vessels in your kidneys (glomeruli), nephrotic syndrome can result in swelling, high cholesterol, malnutrition and eventually kidney failure.

Osteochondritis dissecans

Osteochondritis dissecans occurs when a piece of and bone loosens and separates from the bone.

Polymorphous light eruption

Polymorphous light eruption is a sun-induced skin rash affecting people who develop a sensitivity to sunlight.

Porphyria

Porphyria is a group of inherited disorders that result from buildup of natural chemicals call porphyrins, which can cause nervous system and skin problems.

Psoriatic arthritis

Some people with psoriasis may develop joint pain called psoriatic arthritis. Get the basics here.

Pulmonary hypertension

High blood pressure affecting only the arteries in your lungs is known as pulmonary hypertension. Discover the symptoms, risk factors and treatment for this condition.

Reactive arthritis

Reactive arthritis is an inflammatory condition that develops in response to an infection in another part of your body.

Septic arthritis

Septic arthritis occurs when a joint becomes infected. Find out more about this serious condition.

Thoracic outlet syndrome

Thoracic outlet syndrome is a group of disorders that occur when the nerves or vessels in the shoulder area (thoracic outlet) are compressed.

Thrombophlebitis

Thrombophlebitis occurs when a blood clot and swelling develop in a vein, typically in your leg. The cause often is prolonged inactivity or bed rest.

Thumb arthritis

Thumb arthritis (basal joint arthritis) occurs when the joint at your wrist and the base of your thumb develops osteoarthritis.

Tricuspid atresia

A heart with tricuspid atresia doesn't have a tricuspid valve. This heart defect prevents blood flow from the right atrium to the right ventricle.

Ultrasound

Ultrasound imaging uses high-frequency sound waves to create images of structures in your body.

Urinalysis

Urinalysis can be used to assess your overall health, detect a wide range of disorders, or monitor a medical condition or treatment.

Ventricular septal defect

A ventricular septal defect (VSD) is an abnormal opening between the heart's lower chambers. Untreated, this congenital defect may cause heart failure and pulmonary hypertension.

Wegener's granulomatosis

Wegener's granulomatosis is an uncommon disease that causes blood vessel inflammation that can damage lungs, kidneys and other organs. Untreated, it can be fatal.

X-ray

X-rays are a form of radiation that can make images of your bones and internal organs.

Sep. 19, 2014

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