Symptoms:

Too little vitamin B12 gradually causes nervous system (neurological) problems. The neurological effects may be seen before anemia is diagnosed.

Symptoms may include:

• Bleeding gums
• Diarrhea
• Fatigue
• Impaired sense of smell
• Loss of deep tendon reflexes
• Loss of appetite
• Pallor
• Personality or memory changes
• Positive Babinski's sign
• Rapid heart rate
• Shortness of breath
• Sore mouth
• Tingling and numbness of hands and feet
• Tongue problems
• Unsteady gait, especially in the dark

Signs and tests:

Tests that may used to diagnose or monitor pernicious anemia include:

• Bone marrow examination (only needed if diagnosis is unclear)
• Complete blood count
• Measurement of serum holotranscobalamin II
• Reticulocyte count
• Schilling test
• Serum LDH
• Serum methylmalonic acid (MMA) level
• Serum vitamin B12 level

Pernicious anemia may also alter the results of the following tests:

• Bilirubin
• Cholesterol test
• Gastrin
• Leukocyte alkaline phosphatase
• Peripheral smear
• TIBC

Vitamin B12 deficiency affects the appearance of cells that form on the outer surface of the body and line inner passageways (epithelial cells). An untreated woman may have a false positive Pap smear.