Autoimmune Diseases Dictionary

kidney: One of a pair of organs that filters impurities out of the blood.

lactose intolerance: An inability to digest lactose sugar, which is found in milk products.

large intestine: Also known as the large bowel, the large intestine is wider than the small intestine, and lies between the small intestine and the rectum.

Lhermette's syndrome: Lhermettes syndrome describes the condition in which a person experiences a sensation of electric tingling down the spine when bending down. This is one of the less common multiple sclerosis symptoms.

lumbar puncture spinal tap: A procedure that takes a sampling of the cerebrospinal fluid (the fluid that surrounds the brain and spinal cord) to analyze for proteins associated with MS.

lupus: A common name for systemic lupus erythematosus, a systemic immune disorder that attacks the body's own tissue.

lupus nephritis: A condition where lupus antibodies attack and inflame the kidney, which can lead to renal failure.

lymphoma: The incidence of lymphoma is increased in RA as it is in most autoimmune conditions.

Magnetic Resonance Imaging (MRI): A scan of your brain and/or spinal cord that is used to look for the characteristic patches of MS.

malabsorption: An impaired ability to absorb nutrients through the intestines.

malar erythema: A coin-shaped skin rash associated with discoid lupus, generally appearing on the nose and chin.

malnourishment: A state in which the body receives insufficient or unbalanced amounts of the nutrients it needs to function.

methotrexate: A medicine that makes your immune system less active. Methotrexate is used to treat rheumatoid arthritis, psoriasis and other diseases that are associated with an immune system that is too active. Methotrexate can help people who have these problems. But because it can cause some serious side effects, it must be used carefully.

miscarriage: The body's termination of pregnancy before the fetus is capable of surviving outside of the uterus.

mononeuritis multiplex: The clinical picture that arises from problems with multiple individual nerves serially or almost simultaneously.

multiple sclerosis (MS): A degenerative inflammatory disease that affects the central nervous system. Multiple sclerosis occurs when the body's immune system mistakenly begins to attack the nervous system, making multiple sclerosis an autoimmune disease. It damages the myelin sheath, the material that surrounds and protects your nerve cells. This damage slows down or blocks messages between your brain and your body, leading to the symptoms of MS. Symptoms of this disease include:

• muscle weakness
• sensations such as numbness, prickling or "pins and needles"
• thinking and memory problems
• trouble with coordination and balance
• visual disturbances.

myalgia: Muscle pain.

myelin: A substance rich in protein and lipids (fatty substances) that forms layers around the nerve fibers to insulate the nerves. The nerve can be likened to an electrical cable: While the axon or nerve fiber that transmits the nerve impulse acts like the wire, the myelin sheath is like the insulation around the wire. Myelin is present in both the central nervous system (CNS) and the peripheral nervous system (PNS), but it is only the destruction of CNS myelin that produces the symptoms of MS.

myocarditis: Inflammation of the myocardium, the heart's middle muscle layer.

myositis: Inflammation of muscles.

necrosis: The death of living tissue.

neonatal lupus: A condition sometimes see in the babies of women with systemic lupus erythematosus. Lupus antibodies cross the placenta into the fetus during gestation.

neurologist: A doctor with specialized training in diseases of the nervous system, including MS.

neuromyelitis optica: Neuromyelitis optica (NMO) is an uncommon disease of the central nervous system (CNS) that affects the optic nerves and spinal cord. Individuals with NMO develop optic neuritis, which causes pain in the eye and vision loss, and transverse myelitis, which causes weakness, numbness and sometimes paralysis of the arms and legs. NMO patients may also experience sensory disturbances and loss of bladder and bowel control. This condition can be associated with multiple sclerosis.

non-steroid anti-inflammatory drugs (NSAIDs): A variety of anti-inflammatory drugs not based on steroids.

nystagmus: A tremor that produces jumpy eye movements.

onset: The first observable signs of a disease.

optic neuritis: Optic neuritis is often the first detectable symptom of multiple sclerosis. Symptoms of optic neuritis include:

• blurred vision in one eye
• double vision
• loss in color perception
• pain in the eye that develops within hours.

osteoarthritis: Occurs when the cartilage between bones breaks down, allowing the bones to rub against one another. This "wear and tear" causes joint deterioration and pain. Unlike rheumatoid arthritis, which can affect internal organs, osteoarthritis is confined to the joints.