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

Boils and Carbuncles

Boils and carbuncles are skin infections usually caused by Staphylococcus aureus bacteria (staph). These staph infections form pockets in the skin that are filled with pus, a fluid that includes bacteria, dead skin cells and infection-fighting white blood cells. Whether the pocket of pus is called a boil or a carbuncle depends on its location and size: A boil, also called a furuncle, begins as a painful infection of a single hair follicle. Boils can grow to be larger than a golf ball, and they commonly occur on the buttocks, face, neck, armpits and groin. A carbuncle is a deeper skin infection that involves a group of infected hair follicles in one skin location. Carbuncles often are found on the back of the neck, shoulders, hips and thighs, and they are especially common in middle-aged or elderly men. People with diabetes are more likely to develop carbuncles. (Locked) More »

Bowel Obstruction

In a bowel obstruction (intestinal obstruction), a blockage prevents the contents of the intestines from passing normally through the digestive tract. The problem causing the blockage can be inside or outside the intestine. Inside the intestine, a tumor or swelling can fill and block the inside passageway of the intestine. Outside the intestine, it is possible for an adjacent organ or area of tissue to pinch, compress or twist a segment of bowel. A bowel obstruction can occur in the small bowel (small intestine) or large bowel (large intestine or colon). Also, a bowel obstruction can be total or partial, depending on whether any intestinal contents can pass through the obstructed area. In the small intestine, the most common causes of bowel obstruction are: (Locked) More »

Chorionic Villus Sampling

Chorionic villi are small branching structures on one side of the placenta. They anchor the placenta to the wall of the uterus, almost like the roots of a plant. They have another root-like function, which is to absorb nutrients from the mother's blood in the lining of her uterus, and to deliver these to the umbilical cord. These structures contain cells from the developing fetus. A test that removes a sample of these cells through a needle is called chorionic villus sampling (CVS). CVS answers many of the same questions as amniocentesis about diseases that the baby might have. Diseases that can be diagnosed with CVS include Tay-Sachs, sickle cell anemia, cystic fibrosis, thalassemia, and Down syndrome. (Rh incompatibility and neural tube defects, however, can be diagnosed only through amniocentesis.) CVS can be done earlier in pregnancy than amniocentesis and can be done when there is not enough amniotic fluid to allow amniocentesis. However, it has some extra risks when compared with amniocentesis. CVS can be done between the 10th and 13th weeks of pregnancy. Tell your doctor ahead of time if you have ever had an allergic reaction to lidocaine or the numbing medicine used at the dentist's office. (Locked) More »

Chronic Obstructive Pulmonary Disease (COPD)

Chronic obstructive pulmonary disease (COPD) refers to a group of disorders that damage the lungs. These disorders make breathing increasingly difficult over time. The most common forms of COPD are chronic bronchitis and emphysema. Both are chronic illnesses that impair airflow in the lungs. Most cases of COPD are related to cigarette smoking. (Locked) More »

Friedreich Ataxia

Friedreich's ataxia is an inherited (genetic) disorder that causes certain nerve cells to deteriorate over time. In many cases, this disorder also affects the heart, certain bones and cells in the pancreas that produce insulin. The illness typically begins with difficulty walking. People with Friedreich's ataxia develop clumsy, shaky movements of the legs (called gait ataxia) during childhood or early adolescence. In rare cases, symptoms appear in infants and in middle-aged adults. As the disease gets worse, people may develop bony deformities of the spine and feet, loss of sensation in the limbs, speech problems, abnormal eye movements, heart disease and diabetes. Scientists believe that many symptoms of Friedreich's ataxia are related to abnormally low levels of frataxin, a protein that helps to protect cells from "free radicals," which are toxic (poisonous) byproducts of the cells' energy production. In a person with Friedreich's ataxia, a segment of the genetic code on chromosome number 9 can have as many as 1,000 repetitions, instead of the normal range of 7 to 22. These repetitions produce an error that leads to a decreased production of frataxin. As free radicals accumulate within cells, and more and more cells are destroyed or altered, the long-term effects of Friedreich's ataxia lead to a thinner spinal cord, enlarged heart muscle, disturbances in speech and eye movement, and loss of the pancreas's ability to regulate blood sugar. Ultimately, almost everyone with Friedreich's ataxia is confined to a wheelchair, and a large percentage of people develop serious heart problems, including heart failure. Friedreich's ataxia is a recessive disorder, which means that 2 copies of the abnormal ninth chromosome must be inherited (1 from each parent). People who inherit only one abnormal copy (approximately 1 of every 90 Americans of European ancestry) don't have the disease, but are "carriers" who can pass the abnormal chromosome to their children. (Locked) More »

Hearing Loss in Adults

Hearing loss is a decrease in the ability to perceive sounds. It can be partial or total, sudden or gradual, temporary or permanent. It can affect one ear or both. In general, the risk of hearing loss increases with age. Sound enters the ear and strikes the eardrum. This causes the eardrum to vibrate. The eardrum's vibrations are amplified through the middle ear by three tiny bones. Inside the ear, the vibrations are transformed into nerve impulses. These nerve impulses travel to the brain, where they are interpreted as sounds. (Locked) More »

Hyperthyroidism

Hyperthyroidism is a condition in which your body makes too much thyroid hormone. It is also called overactive thyroid. Thyroid hormones are made by the thyroid gland. The thyroid gland is located in the lower front of the neck. Thyroid hormones regulate the body's energy. When levels of thyroid hormones are unusually high, the body burns energy faster and many vital functions speed up. (Locked) More »

Meningitis

Meningitis is an inflammation of coverings (meninges) of the brain and spinal cord. Most often it is caused by a viral or bacterial infection. Other infectious agents such as fungi can also cause meningitis. Rarer causes of meningitis include atypical drug reactions and systemic lupus erythematosus. Viral, or aseptic, meningitis is the most common type. In general, viral meningitis is not directly contagious. Anyone can get viral meningitis, but it occurs most often in children. Many different viruses can cause meningitis; an enterovirus tends to be the usual culprit. Viral meningitis due to enterovirus peaks in mid-summer through early autumn. But it can occur any time of the year. Except for the rare case of herpes meningitis, viral meningitis will resolve on its own after 7 to 10 days. Bacterial meningitis, formerly called spinal meningitis, is a very serious and potentially fatal infection. It can strike very healthy people, but infants and older people are more susceptible. In the past, the three most common types of bacterial meningitis were caused by Neisseria meningitidis, Haemophilus influenza and Streptococcus pneumoniae. Now that we have very effective vaccines to help prevent all three types, bacterial meningitis in otherwise healthy children and adults occurs less often. (Locked) More »

Multiple Sclerosis

Multiple sclerosis (MS) is a neurological illness that affects the brain and spinal cord. Symptoms of the disease be intermittent (they come and go). Or MS can be progressive. This means it worsens over time.  Nerve cells called neurons send out long "fingers" called axons.  The axons from one neuron send signals to another neuron that may be a long ways away.  A substance called myelin normally is wrapped around the axons. Myelin helps the axon transmit signals from one neuron to another.   In MS, inflammation damages both the neurons and the myelin. This disrupts or slows nerve signals. The inflammation also leaves areas of scarring called sclerosis.  (Locked) More »

Squamous Cell Carcinoma of the Skin

Squamous cells are small, flat skin cells in the outer layer of skin. When these cells become cancerous, they typically develop into flat or raised, rounded skin tumors. Sometimes the skin around the tumors gets red and swollen. Most cases of squamous cell carcinoma occur in people who have spent lots of time in the sun—especially those with fair skin and blue eyes. Some cases develop on skin that has been injured or exposed to cancer-causing agents. This type of squamous cell cancer can develop on: Scars, burns, and long-lasting ulcers (Locked) More »