Subacute Combined Degeneration (SACD)

Subacute Combined Degeneration (SACD)

Subacute combined degeneration (SACD) is a neurological condition characterized by the degeneration of the spinal cord, particularly the dorsal and lateral columns. It is most commonly caused by vitamin B12 deficiency, although other factors can contribute to its development.

Vitamin B12, also known as cobalamin, plays a crucial role in the formation of myelin, the protective covering of nerves. When there is a deficiency of vitamin B12, the myelin sheath deteriorates, leading to neurological symptoms.

The classic cause of vitamin B12 deficiency is pernicious anemia, an autoimmune condition where the body’s immune system attacks the cells in the stomach that produce intrinsic factor, a protein necessary for the absorption of vitamin B12. Other causes of vitamin B12 deficiency include poor dietary intake, malabsorption disorders (such as celiac disease or Crohn’s disease), and certain medications.

Symptoms of subacute combined degeneration can include:

  1. Numbness and tingling in the hands and feet (peripheral neuropathy)
  2. Weakness and difficulty walking
  3. Loss of proprioception (sense of body position)
  4. Impaired vibration sense
  5. Balance and coordination problems
  6. Memory problems and cognitive changes (in severe cases)

Diagnosis of SACD typically involves clinical evaluation, blood tests to measure vitamin B12 levels, and sometimes additional tests like MRI to assess spinal cord changes.

Treatment involves addressing the underlying cause of vitamin B12 deficiency, often through vitamin B12 supplementation, either orally or via injections. In cases of pernicious anemia, lifelong vitamin B12 supplementation may be necessary. Early detection and treatment are essential to prevent permanent neurological damage and to potentially reverse symptoms.