The Nerve Damage of Diabetes
Focal Neuropathy (Including Multiplex Neuropathy) continued...
This kind of neuropathy is unpredictable and
occurs most often in older people who have mild diabetes. Although focal
neuropathy can be painful, it tends to improve by itself after a period of
weeks or months without causing long-term damage.
People with diabetes are also prone to
developing compression neuropathies. The most common form of compression
neuropathy is carpal tunnel syndrome. Asymptomatic carpal tunnel syndrome
occurs in 20 to 30 percent of people with diabetes, and symptomatic carpal
tunnel syndrome occurs in 6 to 11 percent. Numbness and tingling of the hand
are the most common symptoms. Muscle weakness may also develop.
Diabetic Neuropathy Can Affect Virtually Every Part of the Body
Diffuse (Peripheral) Neuropathy
Diffuse (Autonomic) Neuropathy
Pelvis and lower back
How Do Doctors Diagnose Diabetic Neuropathy?
A doctor diagnoses neuropathy based on
symptoms and a physical exam. During the exam, the doctor may check muscle
strength, reflexes, and sensitivity to position, vibration, temperature, and
light touch. Sometimes special tests are also used to help determine the cause
of symptoms and to suggest treatment.
A simple screening test to check point
sensation in the feet can be done in the doctor's office. The test uses a nylon
filament mounted on a small wand. The filament delivers a standardized 10-gram
force when touched to areas of the foot. Patients who cannot sense pressure
from the filament have lost protective sensation and are at risk for developing
neuropathic foot ulcers. Physicians may order the filament (with instructions
for use) free from the Lower Extremity Amputation Prevention Program, (LEAP)
Bureau of Primary Health Care, Division of Programs for Special Populations,
4350 East West Highway, 9th floor, Bethesda, MD 20814; telephone (301)
Nerve conduction studies
check the flow of electrical current through a nerve. With this test,
an image of the nerve impulse is projected on a screen as it transmits an
electrical signal. Impulses that seem slower or weaker than usual indicate
possible damage to the nerve. This test allows the doctor to assess the
condition of all the nerves in the arms and legs.
is used to see how well muscles respond to electrical impulses
transmitted by nearby nerves. The electrical activity of the muscle is
displayed on a screen. A response that is slower or weaker than usual suggests
damage to the nerve or muscle. This test is often done at the same time as
nerve conduction studies.
employs sound waves. The sound waves are too high to hear, but they
produce an image showing how well the bladder and other parts of the urinary
tract are functioning.
involves removing a sample of nerve tissue for examination. This test
is most often used in research settings.
If your doctor suspects autonomic neuropathy,
you may also be referred to a physician who specializes in digestive disorders
(gastroenterologist) for additional tests.