Lambert-Eaton syndrome is a disorder in which faulty communication between nerves and muscles leads to muscle weakness.
Myasthenic syndrome; Eaton-Lambert syndrome; Lambert-Eaton myasthenic syndrome; LEMS
Lambert-Eaton syndrome is an autoimmune system. This means your immune system mistakenly targets healthy cells and tissues in the body. In this syndrome, substances 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.
Symptoms may include:
Symptoms related to the autonomic nervous system usually occur, and include:
A detailed medical history will be taken to determine risk factors, such as a history of certain cancers.
A physical examination shows:
Tests to help diagnose and confirm the condition may include:
The main goals of treatment are to:
A treatment called plasma exchange usually improves symptoms. Plasma exchange involves removing blood plasma from the body and replacing it with donated plasma. This helps to make sure that any harmful proteins (antibodies) that are interfering with nerve function are removed from the body.
Plasmapheresis may also be effective. During this treatment, the blood is removed from the body. The plasma is separated, the antibodies are removed, and the plasma is returned to the body.
Medications that suppress the immune response, such as prednisone, may improve symptoms in some cases. Medications may also include:
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.
Call your health care provider if symptoms of this condition develop.
Meriggioli MN, Sanders DB. Disorders of neuromuscular transmission. In: Daroff RB, Fenichel GM, Jankovic J, Mazziotta JC, eds. Bradley’s Neurology in Clinical Practice. 6th ed. Philadelphia, Pa: Saunders Elsevier;2012:chap 78.
Vincent A, Evoli A. Disorders of neuromuscular transmission.In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 430.
Reviewed By: Luc Jasmin, MD, PhD, Department of Neurosurgery at Cedars-Sinai Medical Center, Los Angeles, and Department of Anatomy at UCSF, San Francisco, CA. Review provided by VeriMed Healthcare Network. David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.