From the Research
When evaluating paresthesia in the emergency room, essential laboratory tests include a complete blood count (CBC), comprehensive metabolic panel (CMP), calcium, magnesium, phosphorus, vitamin B12, folate, thyroid function tests (TSH, free T4), and hemoglobin A1c, as these tests help identify common causes of paresthesia such as electrolyte abnormalities, vitamin deficiencies, thyroid dysfunction, and diabetes 1.
Key Laboratory Tests
- Complete blood count (CBC) to assess for anemia or other blood-related abnormalities
- Comprehensive metabolic panel (CMP) to evaluate electrolyte levels and kidney function
- Calcium, magnesium, and phosphorus levels to identify electrolyte imbalances
- Vitamin B12 and folate levels to assess for deficiencies
- Thyroid function tests (TSH, free T4) to evaluate thyroid function
- Hemoglobin A1c to assess for diabetes or glucose control issues
Additional Tests
In cases of acute onset or concerning presentations, additional tests may include:
- Creatine kinase to assess for rhabdomyolysis
- Toxicology screening if drug-related causes are suspected
- Inflammatory markers like ESR or CRP if inflammatory neuropathies are considered
- Blood gas analysis if respiratory involvement is present
Clinical Considerations
The specific combination of tests ordered should be tailored to the patient's presentation, with particular attention to:
- Onset timing and distribution of symptoms
- Associated neurological findings
- Relevant medical history, including diabetes, thyroid disease, or vitamin deficiencies Prompt identification of treatable causes like electrolyte abnormalities can lead to rapid symptom resolution, as seen in a case where a patient with pernicious anemia presented with paresthesia and was treated with intramuscular vitamin B12 injections, leading to near complete resolution of symptoms 1.