Diseases & Conditions

The human body is a remarkable structure. It's designed to efficiently manage the wear and tear of everyday life and fend off all sorts of threats. Most of us are healthy for most of our lives. But we're also susceptible to hundreds of injuries, diseases, and conditions. Some are quite common, others are extremely rare. Here are some of the most common conditions that affect humans.


Diseases & Conditions Articles

Ask Harvard Medical School Video Series

Get health tips from the faculty physicians of Harvard Medical School.  Each video is one to three minutes in length and the video library covers a broad variety of topics related to health and wellness. More »

Antibiotic resistance and the dangers of superbugs

The bacteria that cause disease are remarkably resilient and can develop ways to evade the drugs meant to kill or weaken them. This phenomenon is called antibiotic resistance and it is due largely to the growing, and often careless, use of antibiotics. Today, bacterial infections in the United States and throughout the world are becoming resistant to the drugs we rely on to treat them. Antibiotic resistance has been called one of the world's most pressing public health problems. The smart use of antibiotics is the key to controlling the spread of antibiotic resistant bacteria and the rise of superbugs—bacteria that cause infections that are difficult if not impossible to treat. More »

Psoriatic Arthritis

Psoriatic arthritis is a chronic (long-lasting) disease in which a person with psoriasis develops the symptoms and signs of arthritis joint pain, stiffness and swelling. Psoriasis is a common, inherited skin condition that causes grayish-white scaling over a pink or dull-red skin rash. Psoriasis can develop before or after the arthritis, but psoriasis develops first in about 75% of cases. A person may begin to get morning joint stiffness before the arthritis is recognized. People who have psoriasis that involves the nails, especially nail pitting, are much more likely to develop arthritis than those without this problem (50% versus 10%). The cause of psoriatic arthritis is unknown. There is some evidence that infection or trauma can play a role in the development of the disease. For example, psoriatic arthritis seems to flare up in people whose immune systems are affected by human immunodeficiency virus (HIV) infection. Also, heredity seems to play a role. Up to 40% of people with psoriatic arthritis have a family history of skin or joint disease. Certain genes seem to be involved in certain types of psoriatic arthritis. For example, the gene HLA-B27 has been associated with psoriatic spondylitis. (Locked) More »

Scoliosis

A normal spine has several front-to-back curves between the neck and the pelvis. In scoliosis, the spine curves abnormally to the side or twists. Although scoliosis seems to run in some families, most cases appear for unknown reasons in children and adolescents who previously had a straight spine. Scoliosis without a known cause is called idiopathic scoliosis. Girls and boys are affected equally by idiopathic scoliosis, but girls with this condition are more likely to develop curves that get big enough to require treatment. (Locked) More »

Somatization Disorder

A person with somatization disorder is chronically preoccupied with numerous "somatic" (physical) symptoms over many years. These symptoms, however, cannot be explained fully by a non-psychiatric diagnosis. Nonetheless, the symptoms cause significant distress or impair the person's ability to function. The person is not "faking." Somatization disorder is a medical problem. The disorder, however, is probably related to brain functioning or emotional regulation rather than the area of the body that has become the focus of the patient's attention. The symptoms are real and are not under the person's conscious control. People with somatization disorder report multiple medical problems over many years, involving several different areas of the body. For example, the same person might have back pain, headaches, chest discomfort, and stomach or urinary distress. Women often report irregular periods. Men may report erectile dysfunction (impotence). The person may: Describe symptoms in dramatic and emotional terms Seek care from more than one physician at the same time Describe symptoms in vague terms Lack signs of defined medical illness Have complaints that medical tests fail to support People with somatization disorder do get diagnosable medical illnesses, too, so doctors must be careful not to dismiss symptoms too easily. A person with somatization disorder also may have symptoms of anxiety and depression. He or she may begin to feel hopeless and attempt suicide, or may have trouble adapting to the stresses of life. The person may abuse alcohol or drugs, including prescription medications. Spouses and other family members may become distressed because the person's symptoms continue for long periods of time and no medical treatment seems to help. Symptoms of somatization disorder vary by culture, sometimes depending on how illness or "sick roles" are viewed in a given culture. Cultural factors also affect the proportions of men and women with the disorder. Female relatives of people with somatization disorder are more likely to develop the disorder. Male relatives are more likely to develop alcoholism and personality disorder. Scientists do not know the cause of the symptoms reported by people with somatization disorder, but researchers have some theories. It is possible, for example, that people with this disorder perceive bodily sensations in an unusual way. Or they may describe feelings in physical (rather than mental or emotional) terms. Trauma or stress may cause a person's physical sensations to change.   (Locked) More »

Chronic Laryngitis

Laryngitis is an inflammation of the larynx, the "voice box" that contains the vocal cords in the upper portion of the neck. Laryngitis occurs in two forms, acute and chronic. Acute laryngitis typically is a brief illness producing hoarseness and a sore throat. In most cases, an upper respiratory tract infection causes it. Chronic laryngitis is a more persistent disorder that produces lingering hoarseness and other voice changes. It usually is painless and has no significant sign of infection. (Locked) More »

Swallowed Object

What Is It? Young children and, sometimes, older children and adults may swallow toys, coins, safety pins, buttons, bones, wood, glass, magnets, batteries or other foreign objects. These objects often pass all the way through the digestive tract in 24 to 48 hours and cause no harm. But problems may arise when objects are stuck for a long time, are sharp, or contain corrosive materials. Complications can include tears in the esophagus (the tube that connects the mouth and stomach), movement of the object into the tissue of the esophagus, and infection. Small magnets can pose a special problem. If more than one is swallowed, they can stick together and erode through tissue. Three areas of the esophagus are the most likely places for objects to lodge: At the level of the collarbones (clavicles) — the most common place At the center of the chest Just before the esophagus meets the stomach, near the bottom of the rib cage Objects also may get stuck in any part of the esophagus that has been injured previously.   (Locked) More »