STIFF PERSON SYNDROME

ALTERNATE NAMES

Stiff Man Syndrome; Stiffperson’s Syndrome; Moersch-Woltmann Syndrome; Moersch-Woltman Condition; SPS; SMS; Stiff Baby Syndrome; Focal Stiff Person Syndrome; Stiff Limb Syndrome; Jerking Stiff Person Syndrome; Progressive Encephalomyelitis with Rigidity and Myoclonus; PERM

DESCRIPTION

Stiff Person Syndrome (SPS) is a rare neurological disorder with features of an autoimmune disease. SPS is characterized by muscle rigidity that waxes and wanes with painful muscle spasms, progressive muscle stiffness in the trunk and extremities, abnormal posture, and sensitivity to stimuli such as noise, touch, and emotional distress.

SPS is frequently associated with other autoimmune diseases such as diabetes and thyroiditis. Other diseases associated with SPS include breast cancer, epilepsy, and paraneoplatic syndrome.

DIAGNOSTIC TESTING, PHYSICAL FINDINGS, AND ICD-9-CM CODING

Diagnostic testing: SPS is diagnosed by testing profiles including anti-GAD (glutamic acid decarboxylase), antipancreatic islet cell and anti-amphiphysin antibodies. Electromyelography (EMG) is commonly obtained; EEF and lumbar puncture may be used as diagnostic tools. Imaging tests are indicated only in special cases.

ICD-9: 333.91

ONSET AND PROGRESSION

SPS may begin at any age, most commonly between 30 – 50 years of age.

Individuals with SPS may experience frequent falls with severe injuries because they lack normal defensive reflexes. SPS can occur in children including infants, although presentation is different from adults. Infants with this disorder are markedly hypertonic at birth and are at high risk of sudden infant death. In some cases, muscle tone becomes almost normal by 3 years of age, but generally reappears by adolescence.

TREATMENT

There currently is no cure for SPS, and management focuses on relieving symptoms. Treatment may include benzodiazepine, anticonvulsant medications, intrathecal baclofen, plasmaphersis, intravenous immunoglobulin, and physical or occupational therapies. Psychiatric treatment may be considered when symptoms of depression or anxiety are prominent.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for evaluation:

• Clinical history and examination that describes the diagnostic features of the impairment, progression of neurological symptoms, response to medication, and evaluative tests that rule out other causes of stiffness.

• Electronmyography (EMG)

• Special antibody testing (see above), particularly anti-GAD antibodies

Suggested Listings for Evaluation:

DETERMINATION

LISTING

Meets Listing

11.17

111.17

Medical Equals

11.06