Differential Diagnosis
The patient's symptoms of fatigue, tingling sensation in both hands, anxiety, nervousness, and neurologic examination findings suggest a nutritional deficiency. Given her vegan diet, certain deficiencies are more likely.
Single most likely diagnosis
- Vitamin B12 (cobalamin): The patient's vegan diet increases the risk of vitamin B12 deficiency, as this vitamin is primarily found in animal products. Symptoms such as fatigue, tingling sensation, anxiety, and nervousness, along with decreased sensation to light touch and vibration, and hyperreflexia, are consistent with vitamin B12 deficiency.
Other Likely diagnoses
- Iron: The patient's heavy menstrual flow and vegan diet may contribute to iron deficiency, which can cause fatigue, pale skin, and decreased sensation.
- Folic acid: Although less likely than vitamin B12, folic acid deficiency can also occur in vegans and may cause similar symptoms, including fatigue and neurological abnormalities.
Do Not Miss
- Calcium: While less likely to cause the patient's specific symptoms, calcium deficiency can have serious consequences, such as osteoporosis and increased risk of fractures, particularly in a vegan individual with a low BMI.
- Magnesium: Magnesium deficiency can cause neurological symptoms, including anxiety, nervousness, and tingling sensations, although it is less likely than vitamin B12 deficiency in this case.
Rare diagnoses
- Vitamin E: Vitamin E deficiency is rare and typically associated with severe malabsorption or genetic disorders. While it can cause neurological symptoms, it is unlikely in this patient.
- Niacin: Niacin deficiency (pellagra) is rare in developed countries and typically associated with malnutrition or specific genetic disorders. The patient's symptoms do not strongly suggest niacin deficiency.