dystrophies

Muscular dystrophy (MD) is a group of more than 30 genetic diseases. They cause weakness of the muscles. Over time, the weakness gets worse and can cause trouble walking and doing daily activities. Some types of MD can also affect other organs.

There are many different types of MD. Some of the more common types include:

• Duchenne muscular dystrophy, which is the most common childhood form. It is severe and affects boys more often than girls. The symptoms usually start between ages 3 and 6.
• Becker muscular dystrophy, which is similar to Duchenne but is less severe and gets worse more slowly. It often starts in the teenage years.
• Congenital muscular dystrophies, which are present at birth or before age 2. They can be mild or severe.
• Facioscapulohumeral muscular dystrophy, which often starts in the teenage years. At first, it affects the muscles of the face, shoulders, and upper arms.

Each of the types of MD can be different in many ways, such as:

• Who is more likely to get them
• Which muscles they affect
• When they appear, such as in infancy, childhood, middle age, or later
• What the symptoms are
• How serious the symptoms are
• How quickly they get worse
• Whether they run in families
• Whether they affect other organs

Even within the same type of MD, people can have different symptoms.

MD is genetic, meaning that it caused by a change in one or more genes. Gene changes are also called gene variants or mutations. The gene changes in MD affect proteins that strengthen and protect muscles.

There are different gene changes that cause each type of MD. And sometimes people who have the same type of MD can have different gene changes.

Muscular dystrophy can run in families, or you can be the first in your family to have a muscular dystrophy.

To find out if you or your child has MD, your health care provider may use:

• A medical and family history
• A physical exam
• Blood and urine tests, including genetic tests and tests for certain enzymes that may be released by damaged muscles
• Muscle biopsies
• Electromyography and nerve conduction studies to find out if muscles are responding the right way to nerve signals
• Heart testing, such as an electrocardiogram (EKG), since some types of MD can cause heart problems
• Exercise tests to measure muscle strength and breathing and detect any increased rates of certain chemicals following exercise
• Imaging tests such as an MRI to look at muscle quality and bulk and measure fatty replacement of muscle tissue

There is no cure for muscular dystrophy. Treatment can help with the symptoms and prevent complications. It usually includes a combination of therapies, such as:

• Physical therapy to help keep muscles flexible and strong
• Occupational therapy to relearn lost motor skills and learn ways to work around weakened muscles
• Respiratory care, such as breathing exercises, oxygen therapy, and ventilators
• Speech therapy to help with speech and swallowing problems
• Assistive devices, such as wheelchairs, splints and braces, and walkers
• Medicines to help delay damage to muscles or minimize the symptoms of MD
• Surgery to treat some of the conditions associated with MD, such as heart problems, scoliosis, and cataracts

NIH: National Institute of Neurological Disorders and Stroke

Complex regional pain syndrome (CRPS) is a chronic pain condition. It causes intense pain, usually in the arms, hands, legs, or feet. It may happen after an injury, either to a nerve or to tissue in the affected area. Rest and time may only make it worse.

Symptoms in the affected area are:

• Dramatic changes in skin temperature, color, or texture
• Intense burning pain
• Extreme skin sensitivity
• Swelling and stiffness in affected joints
• Decreased ability to move the affected body part

The cause of CRPS is unknown. There is no specific diagnostic test. Your doctor will diagnose CRPS based on your signs and symptoms.

There is no cure. It can get worse over time, and may spread to other parts of the body. Occasionally the symptoms go away, either temporarily or for good. Treatment focuses on relieving the pain, and can include medicines, physical therapy, and nerve blocks.

NIH: National Institute of Neurological Disorders and Stroke

Your cornea is the outermost layer of your eye. It is clear and shaped like a dome. The cornea helps to shield the rest of the eye from germs, dust, and other harmful matter. It also helps your eye to focus. If you wear contact lenses, they float on top of your corneas.

Problems with the cornea include:

• Refractive errors
• Allergies
• Infections
• Injuries
• Dystrophies - conditions in which parts of the cornea lose clarity due to a buildup of cloudy material

Treatments of corneal disorders include medicines, corneal transplantation, and corneal laser surgery.

NIH: National Eye Institute

The retina is a layer of tissue in the back of your eye that senses light and sends images to your brain. In the center of this nerve tissue is the macula. It provides the sharp, central vision needed for reading, driving and seeing fine detail.

Retinal disorders affect this vital tissue. They can affect your vision, and some can be serious enough to cause blindness. Examples are:

• Macular degeneration - a disease that destroys your sharp, central vision
• Diabetic eye disease
• Retinal detachment - a medical emergency, when the retina is pulled away from the back of the eye
• Retinoblastoma - cancer of the retina. It is most common in young children.
• Macular pucker - scar tissue on the macula
• Macular hole - a small break in the macula that usually happens to people over 60
• Floaters - cobwebs or specks in your field of vision

NIH: National Eye Institute

Some eye problems are minor and don't last long. But some can lead to a permanent loss of vision.

Common eye problems include:

• Refractive errors
• Cataracts - clouded lenses
• Optic nerve disorders, including glaucoma
• Retinal disorders - problems with the nerve layer at the back of the eye
• Macular degeneration - a disease that destroys sharp, central vision
• Diabetic eye problems
• Conjunctivitis - an infection also known as pink eye

Your best defense is to have regular checkups, because eye diseases do not always have symptoms. Early detection and treatment could prevent vision loss. See an eye care professional right away if you have a sudden change in vision, if everything looks dim, or if you see flashes of light. Other symptoms that need quick attention are pain, double vision, fluid coming from the eye, and inflammation.

NIH: National Eye Institute

Amyloidosis occurs when abnormal proteins called amyloids build up and form deposits. The deposits can collect in organs such as the kidney and heart. This can cause the organs to become stiff and unable to work the way they should.

There are three main types of amyloidosis:

• Primary - with no known cause
• Secondary - caused by another disease, including some types of cancer
• Familial - passed down through genes

Symptoms can vary, depending upon which organs are affected. Treatment depends on the type of amyloidosis you have. The goal is to help with symptoms and limit the production of proteins. If another disease is the cause, it needs to be treated.

Your immune system protects you from disease and infection by attacking germs that get into your body, such as viruses and bacteria. Your immune system can tell that the germs aren't part of you, so it destroys them. If you have an autoimmune disease, your immune system attacks the healthy cells of your organs and tissues by mistake.

There are more than 80 types of autoimmune diseases. They can affect almost any part of your body. For example, alopecia areata is an autoimmune disease of the skin that causes hair loss. Autoimmune hepatitis affects the liver. In type 1 diabetes, the immune system attacks the pancreas. And in rheumatoid arthritis, the immune system can attack many parts of the body, including the joints, lungs, and eyes.

No one is sure why autoimmune diseases happen. But you can't catch them from other people.

Autoimmune diseases do tend to run in families, which means that certain genes may make some people more likely to develop a problem. Viruses, certain chemicals, and other things in the environment may trigger an autoimmune disease if you already have the genes for it.

Millions of Americans of all ages have autoimmune diseases. Women develop many types of autoimmune diseases much more often than men. And if you have one autoimmune disease, you are more likely to get another.

The symptoms of an autoimmune disease depend on the part of your body that's affected. Many types of autoimmune diseases cause redness, swelling, heat, and pain, which are the signs and symptoms of inflammation. But other illnesses can cause the same symptoms.

The symptoms of autoimmune diseases can come and go. During a flare-up, your symptoms may get severe for a while. Later on, you may have a remission, which means that your symptoms get better or disappear for a period of time.

Doctors often have a hard time diagnosing autoimmune diseases. There's usually not a specific test to show whether you have a certain autoimmune disease. And the symptoms can be confusing. That's because many autoimmune diseases have similar symptoms. And some symptoms, such as muscle aches, are common in many other illnesses. So it can take a long time and some visits to different types of doctors to get a diagnosis.

To help your doctor find out if an autoimmune disease is causing your symptoms,:

• Learn about the health conditions in your family history. What health problems did your grandparents, aunts, uncles, and cousins have? Write down what you learn and share it with your doctor.
• Keep track of your symptoms, including how long they last and what makes them better or worse. Share your notes with your doctor.
• See a specialist who deals with the symptoms that bother you most. For example, if you have rash, see a dermatologist (skin doctor).

The treatment depends on the disease. In most cases, the goal of treatment is to suppress (slow down) your immune system, and ease swelling, redness, and pain from inflammation. Your doctor may give you corticosteroids or other medicines to help you feel better. For some diseases, you may need treatment for the rest of your life.

Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly throughout your life. During childhood and your teens, your body adds new bone faster than it removes old bone. After about age 20, you can lose bone faster than you make bone. To have strong bones when you are young, and to prevent bone loss when you are older, you need to get enough calcium, vitamin D, and exercise. You should also avoid smoking and drinking too much alcohol.

Bone diseases can make bones easy to break. Different kinds of bone problems include:

• Low bone density and osteoporosis, which make your bones weak and more likely to break
• Osteogenesis imperfecta makes your bones brittle
• Paget's disease of bone makes them weak
• Bones can also develop cancer and infections
• Other bone diseases, which are caused by poor nutrition, genetics, or problems with the rate of bone growth or rebuilding

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases

Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many of these diseases are genetic. Sometimes the cause is a medical condition such as alcoholism, a tumor, or a stroke. Other causes may include toxins, chemicals, and viruses. Sometimes the cause is unknown.

Degenerative nerve diseases include:

• Alzheimer's disease
• Amyotrophic lateral sclerosis
• Friedreich ataxia
• Huntington's disease
• Lewy body disease
• Parkinson's disease
• Spinal muscular atrophy

Degenerative nerve diseases can be serious or life-threatening. It depends on the type. Most of them have no cure. Treatments may help improve symptoms, relieve pain, and increase mobility.

People with dwarfism have short stature. This means that their height is under 4' 10" as an adult. They are usually of normal intelligence. Dwarfism most often does happen in families where both parents are of average height.

More than 300 different conditions can cause dwarfism. Achondroplasia is the most common type of dwarfism. Achondroplasia is a genetic condition that affects about 1 in 15,000 to 1 in 40,000 people. It makes your arms and legs short in comparison to your head and trunk. You may also have a larger head and weak muscle tone. Other genetic conditions, kidney disease, and problems with metabolism or hormones can also cause dwarfism.

The conditions that cause dwarfism can also cause other health problems. Most of them are treatable. It is important to have regular checkups throughout your life. With proper medical care, most people with dwarfism have active lives and live as long as other people.