Lambert-Eaton myasthenic syndrome
Overview
Lambert-Eaton myasthenic syndrome (LEMS) is a rare condition that affects the signals sent from the nerves to the muscles.
Symptoms
The symptoms of LEMS develop gradually over weeks or months. The main symptoms are weakness in the legs, arms, neck and face, as well as problems with automatic body functions, such as controlling blood pressure. Common symptoms include: aching musclesfeeling very tired all the time (fatigue)difficulty walking and climbing stairsdifficulty lifting objects or raising the armsdrooping eyelids,dry eyesand blurred visionswallowing problemsdizzinessupon standingadry mouthconstipationerectile dysfunctionmuscle weakness that gets worse with time See a GP if you have a combination of these symptoms.
Causes
LEMS is caused by the body's natural defences (the immune system) mistakenly attacking and damaging the nerves. Normally, nerve signals travel down the nerves and stimulate the nerve endings to release a chemical called acetylcholine. This chemical then helps activate the muscles. If the nerve endings are damaged, the amount of acetylcholine they produce decreases, which means nerve signals do not reach the muscles properly. It's not known what triggers the immune system to attack the nerves. It's often associated with lung cancer, but can occur in people without cancer.
Treatment
There's currently no cure for LEMS, but a number of treatments can help reduce the symptoms. These include: treatment for lung cancer– if you have lung cancer, treating it can significantly improve the symptoms of LEMSmedicine to help nerve signals reach the muscles– commonly used medicines include 3,4-diaminopyridine and pyridostigminemedicine to reduce the activity of the immune system (immunosuppressants)– commonly used medicines includesteroid tablets(such asprednisolone),azathioprineandmethotrexateplasmapheresis– a procedure to redirect your blood through a machine that filters out the antibodies attacking your nervesimmunoglobulin therapy– injections of antibodies from donated blood that temporarily stop your immune system attacking your nerves Medicine is the main treatment, although plasmapheresis and immunoglobulin therapy may be recommended in the short term, or if muscle weakness is severe and other treatments have not helped.