In-depth

Acute kidney failure

Acute kidney failure is the sudden loss of your kidneys' ability to filter waste from your bloodstream. Correcting the underlying cause increases the likelihood of recovery.

Amyloidosis

Amyloidosis causes an abnormal protein buildup in various organs, which can include your heart and kidneys, and can permanently damage them and disrupt their functions.

Amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) — often known as Lou Gehrig's disease — is a degenerative condition causing loss of control of voluntary muscles.

Anaphylaxis

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

Anorexia nervosa

Find out what's behind this life-threatening eating disorder and how to treat it.

Appendicitis

Appendicitis occurs when the appendix becomes inflamed and filled with pus, creating potentially serious complications if not promptly treated.

Arthritis

Arthritis — Comprehensive overview covers arthritis symptoms, arthritis treatment and types of arthritis.

Ataxia

Ataxia describes lack of muscle coordination while performing voluntary movements. A sign of an underlying condition, ataxia can affect any part of your body.

Back pain

Back pain is a common reason for health care visits and missed work. Home treatment and proper body mechanics can help you feel better.

Bed-wetting

Bed-wetting happens — for more than one-third of preschoolers, almost every night. Be patient. Your child is likely to outgrow the problem.

Binge-eating disorder

Binge-eating disorder can make your life miserable and damage your health. Explore treatment strategies to overcome this common eating disorder.

Bipolar disorder

Managing bipolar disorder can be a challenge. Stick to your treatment plan to keep mood swings under control.

Bladder stones

Bladder stones are small masses of minerals in your bladder — often forming as a result of an enlarged prostate, nerve damage or infection.

Blood in urine (hematuria)

Blood in your urine isn't usually serious. But any urinary bleeding lasting more than a day or two should be checked by your doctor.

Bulimia nervosa

Bulimia often leads to a secret life of shame. Find out what's behind this life-threatening disease and how to treat it.

Carcinoid tumors

Carcinoid tumors are rare, slow-growing cancerous tumors that most often occur in the gastrointestinal tract or in the lungs.

Castleman disease

Castleman disease is a rare illness that affects your lymph nodes and other immune-cell structures of your body.

Cervicitis

Cervicitis, an inflammation of the cervix, can result from a sexually transmitted disease. You can take steps to reduce your risk.

Chlamydia

Are you worried you might have chlamydia? Find out how this common sexually transmitted infection is diagnosed and treated.

Chronic daily headaches

Chronic daily headaches strike nearly every day. Aggressive initial treatment and steady, long-term management can help reduce pain and lead to fewer headaches.

Chronic kidney disease

Chronic kidney disease, often caused by diabetes or high blood pressure, is the gradual loss of kidney function. Early detection and treatment can help.

Congenital adrenal hyperplasia

Congenital adrenal hyperplasia is a genetic condition affecting the adrenal glands and interfering with normal growth and development in boys and girls.

Cushing syndrome

Cushing syndrome is caused by an excess of the hormone cortisol, originating from your adrenal glands or from corticosteroid medications you're taking for another illness.

Cyclothymia

Cyclothymia may be a mild form of bipolar disorder, but your fluctuating moods can have serious consequences. Learn about treatment options.

Cystitis

Cystitis is an inflammation of the urinary bladder. It's most often caused by a bacterial infection but may have other causes.

Cystocele

A cystocele occurs when the supportive tissue between a woman's bladder and her vagina weakens and stretches, allowing the bladder to bulge into the vagina.

Dehydration

You normally lose about 10 cups (2.4 liters) of water every day — much more during exercise or illness. Learn how to stay hydrated.

Delayed ejaculation

Delayed ejaculation can have physical or psychological causes. Discover what causes it and what treatments are available.

Delirium

Delirium is a state of confused thinking and lack of awareness that often affects people with dementia, terminal illness or multiple serious medical problems.

Dementia

Dementia — Comprehensive overview covers symptoms, causes and treatments of this mental deterioration.

Diabetes insipidus

Diabetes insipidus is a rare condition characterized by intense thirst and the excretion of large amounts of urine.

Diabetic ketoacidosis

Diabetic ketoacidosis is a serious diabetes complication. Learn the warning signs — and know when to seek emergency care.

Dysarthria

Dysarthria is a speech disorder caused by an inability to control or coordinate the muscles used for speaking.

Dystonia

Dystonia causes involuntary, sustained muscle contractions, resulting in repetitive movements, twisting and abnormal posture.

Edema

Edema — swelling caused by excess fluid in tissues — can affect any part of your body. Treating the underlying cause is key to resolving edema.

Epididymitis

Epididymitis is an inflammation of the tube at the back of the testicle (epididymis). The condition is usually treated with antibiotics.

Erectile dysfunction

Erectile dysfunction (ED) can be the result of physical or psychological causes or both. Discover what causes ED and what treatments are available.

Febrile seizure

Although febrile seizures can be frightening for parents and children, they're generally harmless. Most occur after a sudden fever spike, usually due to an infection.

Heat exhaustion

Heat exhaustion occurs when your body overheats, usually as a result of hot, humid weather. It's preventable, but can be dangerous if not treated.

Heatstroke

Heatstroke is the dangerous escalation of two other heat-related conditions, heat cramps and heat exhaustion. Seek immediate medical attention if you have this condition.

Hemolytic uremic syndrome (HUS)

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

Henoch-Schonlein purpura

Henoch-Schonlein purpura causes inflammation of small blood vessels (vasculitis) and often a purplish rash. It's most common in children ages 2 to 6.

High blood pressure in children

High blood pressure in children and adolescents is often caused by another health condition, but is usually treatable with diet and exercise.

Histoplasmosis

The fungus that causes the lung disease histoplasmosis lurks in soil, chicken coops and caves. Find out if you're at risk.

HIV/AIDS

More than 39 million people are living with HIV — the virus that causes AIDS. Millions more are lipkely to become infected in the next decade. More than 39 million people are living with HIV — the virus that causes AIDS. Millions more are likely to become infected in the next decade.

Horner syndrome

Horner syndrome occurs when certain nerves that travel from your brain to your eyes and face are damaged.

Hydrocele

A hydrocele is a generally harmless fluid-filled sac that surrounds a testicle, causing scrotal swelling. However, it may indicate a more serious condition.

Hyperparathyroidism

Hyperparathyroidism, or overactivity of one or more parathyroid glands, raises blood-calcium levels. The disorder can weaken bones and lead to other serious complications.

Hyponatremia

Hyponatremia is an abnormally low concentration of sodium in the blood. One cause is drinking too much water.

Hypoparathyroidism

Hypoparathyroidism is a disorder in which your parathyroid glands secrete abnormally low levels of parathyroid hormone, causing symptoms such as muscle aches.

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.

Infant jaundice

Infant jaundice, a yellowing of the skin and eyes, is common after birth. Careful monitoring and treatment is important for preventing rare, but serious, complications.

Infant reflux

Spit up happens. Often, changes in feeding technique help keep reflux under control.

Interstitial cystitis

Frequent urination and pelvic pain may indicate interstitial cystitis, a chronic bladder inflammation. There's no cure, but some treatments offer relief.

Interstitial lung disease

Interstitial lung disease causes scarring in the air sacs in the lungs, making breathing more difficult.

Kidney cancer

When kidney cancer is diagnosed and treated early, the chances for recovery are better.

Kidney infection

Kidney infection can permanently damage your kidneys or allow bacteria to spread to your bloodstream. Seek immediate medical attention to avoid life-threatening complications.

Kidney stones

Kidney stones often recur. Find out what causes kidney stones and how to prevent them.

Listeria infection

Most people exposed to listeria don't become ill. But for those at risk of a listeria infection — a foodborne illness — the consequences can be severe.

Lupus

Lupus is a chronic disease that can affect your skin, joints and organs. With proper care, most people with lupus live relatively active, healthy lives.

Lynch syndrome

Lynch syndrome, an uncommon disorder caused by genetic defects, predisposes a person to develop colon cancer and other forms of cancer.

Membranous nephropathy

Your kidney's filtering system is damaged and valuable proteins leak from the body.

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.

Non-Hodgkin's lymphoma

Non-Hodgkin's lymphoma is cancer originating in the lymphatic system. It's caused by abnormal white blood cells, and often the only sign is swollen lymph nodes.

Orchitis

Orchitis, a painful inflammation of one or both testicles, may be caused by the mumps virus or a bacterial infection.

Overactive bladder

Overactive bladder is a problem with bladder function that causes a sudden urge to urinate and may even lead to incontinence.

Pelvic inflammatory disease (PID)

Pelvic inflammatory disease (PID) is the most common preventable cause of infertility in the United States, but some women don't find out soon enough.

Pheochromocytoma

A pheochromocytoma is a rare adrenal gland tumor that can produce large amounts of certain hormones and seriously raise blood pressure.

Pituitary tumors

Pituitary tumors are abnormal growths in the pituitary gland in the brain. Most are noncancerous (benign). Some may cause overproduction of hormones and associated problems.

Postpartum preeclampsia

Postpartum preeclampsia — Comprehensive overview covers symptoms and treatment of this post-pregnancy condition.

Prostate gland enlargement

Can't go like you used to? Prostate gland enlargement can make urination difficult. Treatments for this common condition range from self-care to surgery.

Prostatitis

Prostatitis, inflammation of the prostate gland, can cause significant male pelvic pain and other symptoms.

Retrograde ejaculation

Retrograde ejaculation occurs when semen enters the bladder instead of emerging through the penis during orgasm. Find out about symptoms and treatment.

Rett syndrome

Parenting a child with Rett syndrome can be challenging. Here's what to expect and steps you can take to help your child.

Reye's syndrome

Reye's syndrome is a rare but serious condition linked to giving children aspirin to treat viral infections.

Rickets

Rickets is a severe and prolonged vitamin D deficiency that leads to softening and weakening of the bones in children.

Scrotal masses

A scrotal mass is a lump or other abnormality in the scrotum that may affect the health of testicles. A scrotal mass may be cancerous.

Secondary hypertension

Secondary hypertension is a type of high blood pressure that's caused by another medical condition. Prompt treatment is often necessary to avoid complications.

Sepsis

Most cases of sepsis don't cause serious problems. But severe sepsis and septic shock can lead to death if not treated promptly.

Sexually transmitted diseases

Sexually transmitted diseases — Comprehensive overview covers symptoms, diagnosis and treatment of STDs.

Sjogren's syndrome

Stress incontinence

Do you often leak urine when you cough, sneeze or laugh? Treatment can help.

Testicular torsion

Testicular torsion blocks blood flow to a testicle. Know the signs of this painful condition — and when to see a doctor.

Toxic shock syndrome

Toxic shock syndrome is a life-threatening infection often associated with the use of superabsorbent tampons. But it can also occur in men and children.

Trichomoniasis

Trichomoniasis — Comprehensive overview covers symptoms, causes, treatment of this sexually transmitted infection.

Type 1 diabetes

Type 1 diabetes destroys your body's ability to produce insulin. Learn how you can live an active, healthy life with type 1 diabetes.

Type 2 diabetes

Type 2 diabetes is on the rise — but here's information that may help you stop diabetes in its tracks.

Urinary incontinence

Don't let fear of losing bladder control restrict your activities. With treatment, you can reduce your symptoms and cope more effectively.

Urine color

Changes in urine color can be alarming, but they're often harmless — the result of certain foods, supplements or medications.

Vaginal atrophy

You don't have to accept vaginal problems as part of getting older. Discover treatment options.

Vaginal dryness

Vaginal dryness is a common and uncomfortable condition — but there are effective ways to treat it.

Vasculitis

Vasculitis is an inflammation of the blood vessels. It can affect people of any age. Treatment depends on the type of vasculitis.

Vesicoureteral reflux

Vesicoureteral reflux is the abnormal flow of urine backward from the bladder. Usually found in children, it increases the risk of urinary tract infections.

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.

Wilms' tumor

Wilms' tumor is a rare kidney cancer that primarily affects children.

Feb. 15, 2014