Summary about Disease
Funicular myelosis, also known as subacute combined degeneration of the spinal cord, is a progressive degenerative disease affecting the spinal cord and brain. It is typically caused by a deficiency of vitamin B12 (cobalamin). This deficiency leads to abnormal myelin formation, primarily affecting the dorsal and lateral columns of the spinal cord, resulting in sensory and motor deficits.
Symptoms
Symptoms develop gradually and can include:
Numbness and tingling in the hands and feet (peripheral neuropathy)
Loss of position sense (proprioception), leading to unsteady gait and difficulty with coordination
Muscle weakness, stiffness, and spasticity
Fatigue
Cognitive changes, such as memory loss, irritability, and depression (in severe cases)
Visual disturbances
Optic neuropathy
Causes
The primary cause is Vitamin B12 deficiency. Common causes of B12 deficiency include:
Pernicious anemia: an autoimmune disorder that prevents absorption of B12.
Dietary deficiency: rare, but possible in strict vegans who do not supplement.
Malabsorption: due to conditions like Crohn's disease, celiac disease, or gastric bypass surgery.
Medications: some medications can interfere with B12 absorption (e.g., metformin, proton pump inhibitors).
Parasitic infections: specifically tapeworm infections.
Medicine Used
The primary treatment involves B12 replacement therapy.
Vitamin B12 injections: Usually administered intramuscularly, initially daily or several times per week, then monthly.
Oral Vitamin B12: High-dose oral supplements can be effective, especially when the deficiency is not severe or when injections are not feasible. In addition, physical therapy and occupational therapy may be used to improve motor function and adapt to any lasting deficits.
Is Communicable
Funicular myelosis is not communicable. It is caused by a nutritional deficiency or malabsorption problem, not by an infectious agent.
Precautions
Precautions mainly revolve around preventing B12 deficiency:
Dietary considerations: Ensure adequate B12 intake, especially for vegans and vegetarians, through fortified foods or supplements.
Regular monitoring: Individuals at risk for B12 deficiency (e.g., those with malabsorption issues or taking certain medications) should have their B12 levels monitored regularly.
Early diagnosis and treatment: Seek medical attention promptly if experiencing symptoms suggestive of B12 deficiency or neurological problems.
Individuals with pernicious anemia or other malabsorption issues should adhere to prescribed treatment plans and maintain regular follow-up with their healthcare provider.
How long does an outbreak last?
Funicular myelosis is not an outbreak-related disease. It is a chronic condition that progresses if B12 deficiency is left untreated. The duration of symptoms depends on the severity of the deficiency and how quickly treatment is initiated. Early treatment can often reverse or halt the progression of the disease. Without treatment, it can lead to permanent neurological damage.
How is it diagnosed?
Diagnosis involves:
Medical history and physical examination: Assessing symptoms and identifying risk factors for B12 deficiency.
Blood tests: Measuring serum B12 levels. Methylmalonic acid (MMA) and homocysteine levels are often elevated in B12 deficiency and can be used to confirm the diagnosis even when B12 levels are borderline.
Complete blood count (CBC): To check for macrocytic anemia, a characteristic finding in B12 deficiency.
Neurological examination: Assessing sensory and motor function, reflexes, and coordination.
MRI of the spinal cord: To visualize the spinal cord and rule out other causes of myelopathy. Can show signal changes in the posterior columns.
Electrophysiological studies (nerve conduction studies and electromyography): Can help assess the extent of peripheral nerve involvement.
Timeline of Symptoms
The timeline of symptoms can vary, but generally follows a progressive pattern:
Early: Subtle numbness and tingling in the hands and feet. Mild weakness.
Intermediate: Worsening numbness and tingling, difficulty with balance and coordination, increased muscle weakness, fatigue.
Late: Significant loss of position sense, unsteady gait, spasticity, cognitive changes, visual disturbances. The speed of progression depends on the severity of the B12 deficiency and individual factors. Symptoms can develop over weeks, months, or even years.
Important Considerations
Early diagnosis and treatment are crucial to prevent irreversible neurological damage.
Long-term B12 replacement therapy is often necessary to maintain adequate B12 levels.
Individuals with funicular myelosis may require ongoing physical therapy, occupational therapy, and psychological support.
It is important to identify and address the underlying cause of B12 deficiency to prevent recurrence.
Neurological damage can occur even with mild B12 deficiency if left untreated for an extended period.