Medical Dictionary
A Medical Dictionary of Medical Terminology
  

myasthenic

Neuromuscular Disorders

Neuromuscular disorders affect your neuromuscular system. They can cause problems with:

These disorders can cause your muscles to become weak and waste away. You may also have symptoms such as spasms, twitching, and pain.

Examples of neuromuscular disorders include:

There can be different causes for these diseases. Many of them are genetic.This means they are inherited (run in families) or are caused by a new mutation in your genes. Some neuromuscular disorders are autoimmune diseases. Sometimes the cause is unknown.

Many neuromuscular diseases have no cure. But treatments may improve symptoms, increase mobility, and lengthen life.

Autoimmune Diseases

What are autoimmune diseases?

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.

What causes autoimmune diseases?

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.

Who is at risk for autoimmune diseases?

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.

What are the symptoms of autoimmune diseases?

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.

How are autoimmune diseases diagnosed?

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,:

What are the treatments for autoimmune diseases?

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.

Myasthenia Gravis

What is myasthenia gravis?

Myasthenia gravis, sometimes called MG, is a chronic (long-lasting) disease that causes weakness in your voluntary muscles. The voluntary muscles are the ones that you can control. They include the muscles you use for:

You can also have weakness in other muscles. This weakness gets worse with activity, and better with rest.

Myasthenia gravis is a type of autoimmune disease. In autoimmune diseases, your immune system attacks the healthy cells of your organs and tissues by mistake.

What causes myasthenia gravis?

Myasthenia gravis is caused by an error in how nerve signals are sent to muscles. These signals get blocked at the nerve-muscle junction. This junction is the place where the nerve endings connect with the muscles they control.

Normally, this is how the signals work:

But in someone with myasthenia gravis, the body's own immune system makes antibodies that block the binding of acetylcholine to the muscle. This makes the muscles weaker.

The thymus gland, which is part of your immune system, may play a role in myasthenia gravis. Normally, your thymus gland is active and growing when you are a child. It makes white blood cells to fight infections. At puberty, it starts getting smaller and is replaced by fat. It is usually small by the time you are an adult. But in many adults with myasthenia gravis, the thymus gland stays large. And some people with myasthenia gravis can get thymomas, which are tumors of the thymus. The are usually benign (not cancer), but they can sometimes become cancerous.

Who is more likely to develop myasthenia gravis?

Although myasthenia gravis can affect people of any age, it is most common in young adult women (under age 40) and older men (over age 60). It is usually not inherited (passed down in families).

Myasthenia gravis normally does not affect infants. But it's possible for pregnant people who have myasthenia gravis to pass the antibodies to their unborn babies. The baby can then be born with neonatal myasthenia. This condition is usually temporary, and the symptoms typically go away within two to three months after birth.

What are the symptoms of myasthenia gravis?

The symptoms of myasthenia gravis will depend on which muscles are affected. The symptoms often include:

Different people have different levels of muscle weakness. And the weakness can vary from day to day. Some days it might be mild, and other days it might be worse. Physical activity often makes the muscle weakness worse.

Some people with myasthenia gravis can get severe weakness that affects the muscles that control breathing. This is called a myasthenic crisis, and it is a life-threatening emergency.

How is myasthenia gravis diagnosed?

There are many other conditions that can cause muscle weakness, so myasthenia gravis can be hard to diagnose. To find out if you have myasthenia gravis, your health care provider:

What are the treatments for myasthenia gravis?

There is no cure for myasthenia gravis, but treatments that can improve muscle weakness and help with symptoms. They include:

Lifestyle changes may be helpful for some people. The changes could include regular gentle exercise, getting enough rest, and eating healthy foods.

Some people with myasthenia gravis go into remission. This means that they do not have symptoms. The remission is usually temporary, but sometimes it can be permanent.

NIH: National Institute of Neurological Disorders and Stroke

Popular Medical Dictionary Searches: Ibuprofen  Aspirin  Dementia  Breast Cancer  Fibrosis  Headache  Mesothelioma  Migraine

Medical Dictionary is a free resource to look up medical terms. Trademarks belong to their respective owners.
Copyright 1999 - 2024 Medical Dictionary Inc. All Rights Reserved. Privacy Policy. Medical Disclaimer.