Vitamin B12 deficiency has systemic effects beyond just causing megaloblastic anemia. Symptoms of fatigue, palpitations, headache, and dyspnea are related to anemia. However, B12 deficiency has many neurological effects not associated with anemia; some people can have a B12 deficiency with neurological effects but no anemia. Neurological symptoms include:
- dysesthesia (abnormal sensations including tingling and burning)
- hypoesthesia (numbness)
- ataxia (lack of coordination and unsteady gait)
- decreased proprioception (decreased awareness of where your body is in space)
- vibratory sensation
- other symptoms can include grey hair and glossitis
If pernicious anemia is the cause of the B12 deficiency, the patient can have gastrointestinal symptoms in addition to the above symptoms.
In the case of megaloblastic anemia due to folate deficiency, the symptoms can sometimes be more subtle. Neurological symptoms do not occur as frequently in folate deficiency. However, symptoms of anemia are seen, such as fatigue and extreme tiredness, weakness, shortness of breath, occasionally swelling of the tongue, or growth problems. In pregnant women, a folate deficiency can lead to neural tube defects affecting the spinal cord and brain of the fetus. Therefore, folate supplementation is generally recommended for pregnant women.
