Stiff-Person Syndrome

Syllabus: General Studies Paper 3

French-Canadian singer Celine Dion has opened up about being diagnosed with Stiff-Person Syndrome (SPS), a rare neurological condition that makes the muscles spasm uncontrollably. The disorder has left her with difficulties in walking and singing.

What is Stiff-Person Syndrome?

• It is a syndrome of fluctuating but progressive muscle stiffness and spasm that preferentially affects axial (back and abdominal) muscles, neurological experts noted.
• It is a central nervous system disorder, meaning encephalomyelopathy, in which myelopathic features predominate in most patients. 
• It frequently affects women with a median onset of 35 to 40 years of age.

What are its causes?

• There have been reports that spasms occur at any random time and can be triggered by loud noises, touch, and emotional distress.
• This autoimmune disease is caused by antibodies to proteins, resulting in impaired GABAergic (Gamma amino butyric acid) inhibition of the motor nerves in the brain and spinal cord. “
• It is associated with GAD65 (Glutamic acid decarboxylase) and amphiphysin antibodies. 
• 70 per cent of patients with GAD antibodies have diabetes mellitus as a comorbidity. 
• It is associated with other autoimmune diseases like cerebellitis, myasthenia gravis, hypo/hyperthyroidism, rheumatoid arthritis, systemic lupus erythematosus.
• People with amphiphysin antibodies can have SPS as a paraneoplastic (a symptom of underlying malignancy) manifestation with predominant upper limbs or cranial nerve involvement. 
• The malignancies associated with stiff-person syndrome are breast cancer, ovarian cancer, and small cell carcinoma of the lung.

Common Symptoms

• SPS is known to affect the body posture of a person due to severe pain and stiffness in muscles in the trunk (torso), arms and legs.
• But symptoms can also include a person having greater sensitivity to noise, touch, and emotional distress

Treatment

• Since it is a rare disease with heterogenous clinical manifestations, the diagnosis may be delayed by an average of six years following symptom onset
• Treatment involves the use of both symptomatic agents to enhance GABAergic influences and Immuno modulating treatment aimed at the autoimmune basis of the disease.
• In patients with paraneoplastic Stiff Person Syndrome, identification and eradication of the underlying malignancy can alleviate symptoms