Symptoms & Diagnosis
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The primary symptom of LEMS is muscle weakness, most often in the legs that makes it difficult to walk, climb stairs or get up from a chair.  Symptoms of muscle weakness and fatigue generally progress and patients may experience frequent cramps and muscle aches. Commonly, the muscle weakness involves the legs and hips. Because of the slow progression and rarity of LEMS, patients can go months or even years without a definitive diagnosis. LEMS can have any combination of the following symptoms:

  • Blurred or double vision
  • Breathing problems
  • Constipation
  • Decreased tear production
  • Difficulty chewing
  • Diminished reflexes
  • Drooped eyelids
  • Dry mouth
  • Erectile dysfunction
  • Facial weakness
  • Fatigue
  • Hypoactivity
  • Muscle weakness
  • Pain
  • Reduced sweat
  • Sagging jaw

LEMS patients frequently report that disease significantly affects their Activities of Daily Living (ADLs). ADLs refer to activities that people tend do every day without needing assistance. There are six basic ADLs: eating, bathing, dressing, toileting, transferring (walking) and continence.

Because LEMS shares symptoms with so many other conditions, it is important to have a confirmed diagnosis. A diagnosis of LEMS can be confirmed through a combination of electromyography (EMG) and blood tests.  An EMG evaluates and records electrical activity produced by muscles.  If a diagnosis is confirmed, it is important to screen for cancer.  If no cancer is detected, periodic screenings are recommended for a period of three to four years. Patients with LEMS or who suspect they may have LEMS, should consult a board-certified neurologist who specializes in neuromuscular diseases and disorders.

Blood tests are performed to detect the presence of anti-VGCC (voltage gated calcium channel) antibodies.  Most patients with VGCC-antibody-positivity have small cell lung cancer (SCLC), and approximately 40 percent of LEMS patients have SCLC.

To find a physician who treats LEMS, visit the Muscular Dystrophy Association to inquire about their clinics. You can also find a doctor on American Association of Neuromuscular and Electrodiagnostic Medicine website by going here.

Visit Treatment and About LEMS for more information.