Lambert-Eaton syndrome is an autoimmune disorder. This means your immune system mistakenly targets healthy cells and tissues in the body. In this syndrome, antibodies produced by the immune system attack nerve cells. This makes nerves cells unable to release enough of a chemical called acetylcholine. This chemical transmits impulses between nerves and muscles.
The result is muscle weakness.
Lambert-Eaton syndrome may occur with cancers such as small cell lung cancer or autoimmune disorders such as vitiligo, which leads to a loss of skin pigment.
Symptoms may include:
Weakness or loss of movement that can be more or less severe, including difficulty chewing, difficulty climbing stairs, difficulty lifting objects, difficulty talking, drooping of the head, and the need to use the hands to get up from a sitting or lying position
Identify and treat any underlying disorders, such as lung cancer
Give treatment to help with the weakness
A treatment called plasma exchange or plasmapheresis usually improves symptoms. This involves removing blood plasma from the body and replacing it with other proteins (such as albumin) or with donated plasma. This helps make sure that any harmful proteins (antibodies) that are interfering with nerve function are removed from the body.
Medications that suppress the immune response, such as prednisone, may improve symptoms in some cases. Medications may also include:
Anticholinesterase medications, such as neostigmine or pyridostigmine (although these are not very effective when given alone)
3, 4-diaminopyridine, which increases the release of acetylcholine from nerve cells
The symptoms of Lambert-Eaton syndrome may improve by treating the underlying disease, suppressing the immune system, or removing the antibodies. However, not everyone responds well to treatment.
Vincent A, Evoli A. Disorders of neuromuscular transmission. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 430.
Joseph V. Campellone, MD, Department of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.