Blood Tests for Neurological Disorders

Blood tests for neurological disorders help uncover medical causes of nerve and brain symptoms—such as numbness, weakness, memory loss, seizures, headache, or balance problems. Many neurologic conditions begin silently or mimic one another. Lab testing offers a proactive, step-by-step screen for reversible or systemic causes (vitamin and thyroid problems, autoimmunity, infection, toxins, metabolic issues) and provides context alongside imaging and specialist evaluation.

A practical approach starts with general health labs (CBC/CMP), glucose/A1c, thyroid (TSH), and vitamin B12 with methylmalonic acid (MMA), then adds targeted panels for neuropathy, neuroinflammation, neuromuscular weakness, dementia, seizures, stroke risk, or toxic exposures. Blood tests support screening, diagnosis, and monitoring, but they do not replace a clinician’s exam, MRI/CT, EEG/EMG, or—when indicated—lumbar puncture.

Signs, Symptoms & Related Situations

• Sensory & movement: numbness/tingling, burning feet, shooting pain, weakness, muscle cramps, tremor, gait imbalance

• Thinking & behavior: memory loss, word-finding trouble, confusion, personality or sleep changes

• Headache & vision: new or severe headaches, visual loss/double vision, jaw pain with chewing (giant-cell arteritis concern)

• Seizure/episodes: loss of awareness, staring spells, convulsions, sudden collapse

• Autonomic & systemic: dizziness on standing, palpitations, heat/cold intolerance, unexplained weight change, fatigue

• Exposure & risks: recent infection or tick bite, new medication/supplement use, alcohol or occupational chemicals, diabetes/metabolic syndrome, autoimmune or clotting history, family neurologic disease

• Urgent care now: stroke-like symptoms (face/arm/leg weakness, speech/vision loss), high fever with severe headache/stiff neck, rapidly worsening weakness, or new seizures

Symptoms require evaluation by a qualified clinician.

Why These Tests Matter

What testing can do

• Screen reversible causes of neurologic symptoms (B12 deficiency, thyroid disease, infections, toxins)

• Differentiate patterns (autoimmune, inflammatory, metabolic, vascular) and prioritize imaging or referrals

• Monitor trends in chronic conditions and treatment safety

What testing cannot do

• Diagnose MS, epilepsy, or stroke on blood tests alone—specialist assessment and imaging/EEG/CSF are often required

• Replace a neurologic exam or provide treatment/dosing advice

• Detect every cause; some disorders need genetic, CSF, or tissue studies

What These Tests Measure (at a glance)

• General screen: CBC/CMP (anemia, infection, electrolytes, liver/kidney), A1c/fasting glucose (diabetes), TSH ± Free T4 (thyroid).

• Vitamin & nutrition: Vitamin B12 with MMA (functional deficiency), folate, vitamin D, thiamine (B1), vitamin B6 (both low and high can cause neuropathy), vitamin?E.

• Inflammation & autoimmunity: ESR/CRP; ANA with ENA/dsDNA, SSA/SSB, RF/anti-CCP; ANCA (PR3/MPO); complements C3/C4; cryoglobulins.

• Neuro-specific autoantibodies (serum):

  • Myasthenia gravis: AChR binding/blocking, MuSK

  • Demyelinating disorders: AQP4-IgG (NMOSD), MOG-IgG

  • Peripheral neuropathies: anti-ganglioside (GM1, GD1a, GQ1b), anti-MAG

  • Autoimmune encephalitis (select serum markers): NMDA-R, LGI1, CASPR2, GAD65 (often paired with CSF testing per clinician)

• Infections with neurologic impact (as indicated): HIV 4th-generation, syphilis (RPR/treponemal), Lyme two-tier testing, hepatitis B/C, TB context when relevant.

• Vascular & stroke risk: lipid panel ± ApoB/Lp(a), homocysteine, antiphospholipid antibodies (cardiolipin, β2-glycoprotein I, lupus anticoagulant); clinician-directed thrombophilia studies in selected cases.

• Toxins & metals (exposure-based): lead, mercury, arsenic; copper/ceruloplasmin (Wilson disease context); ammonia (encephalopathy).

• Neuromuscular muscle injury: CK, aldolase.

• Celiac-neurology link: tTG-IgA with total IgA (or deamidated gliadin) for gluten-related ataxia/neuropathy.

• Emerging dementia biomarkers (where available): plasma p-tau, Aβ42/40 ratio, neurofilament light (NfL)—to be used with specialist evaluation, not alone.

Quick Build Guide

How the Testing Process Works

1. Choose a starting set based on your symptoms (see Quick Build Guide).

2. Provide samples: standard blood draw; fasting only if your order includes fasting lipids/glucose.

3. Add targeted tests guided by results and history (autoimmune, infection, toxin, neuromuscular).

4. Combine with clinical tools: results are interpreted with your exam, MRI/CT, EEG/EMG, or CSF when needed.

5. Monitor trends: repeat key markers to confirm abnormalities or track response and safety.

Interpreting Results (General Guidance)

• Low B12 with elevated MMA: supports functional B12 deficiency and neuropathy risk.

• Abnormal TSH/Free T4: thyroid disease can mimic cognitive or neuromuscular symptoms.

• High ESR/CRP with systemic symptoms: consider inflammatory/autoimmune causes; escalate to specialist.

• Positive neuro-autoantibodies (AChR, AQP4, MOG, NMDA-R, etc.): suggest immune-mediated disease—confirm with specialist testing and imaging.

• Positive infections (HIV, syphilis, Lyme): require clinician review; some results need confirmatory testing.

• Elevated heavy metals or ammonia: indicate exposure or metabolic causes—address promptly with your clinician.

• Dementia biomarkers: supportive, not diagnostic alone; use with cognitive testing and imaging.
  Always interpret results with a qualified healthcare professional; patterns and trends matter more than a single value.

Choosing Panels vs. Individual Tests

• Foundational neurology screen: CBC • CMP • TSH • A1c • B12 + MMA • ESR/CRP

• Targeted panels: Neuropathy, Autoimmune/Neuroinflammation, Infection, Toxin/Heavy Metals, Cognitive Health, Stroke Risk

• Add individual markers when a panel flags a direction (e.g., AChR Ab, AQP4-IgG, antiphospholipid Ab)

FAQs

Can blood tests diagnose multiple sclerosis (MS)?
No. Blood tests rule out mimics and support the work-up, but MRI and sometimes CSF are key for MS.

What labs help with numbness and tingling?
Start with A1c, B12 + MMA, TSH, and CMP; add autoantibodies, metals, and B-vitamins based on history.

Are there blood tests for Alzheimer’s disease?
Emerging biomarkers (p-tau, Aβ42/40, NfL) exist where available, but they’re not stand-alone diagnoses and should be used with specialist guidance.

Do I need to fast?
Only for fasting glucose or lipid testing. Most neuro-related labs don’t require fasting.

Can infections cause neurologic symptoms?
Yes. HIV, syphilis, Lyme and others can affect the nervous system; blood tests help screen and confirm.

Why both B12 and MMA?
MMA rises when tissues are short on B12, even with “normal” B12—useful for early deficiency.

When should I see a neurologist?
If symptoms are progressive, focal, or disabling, or labs are clearly abnormal, seek specialist evaluation.

Related Categories & Key Tests

• Neurological Disorders Tests Hub

• All Cognitive Health Tests • Brain Health • Alzheimer’s Disease • Stroke Tests • Heavy Metal Tests • Infectious Disease (Lyme, HIV, Syphilis) • Autoimmune Panels

• Key Tests: CBC • CMP • A1c • TSH/Free T4 • Vitamin B12 + MMA • Folate • Vitamin D • B1 • B6 • ESR/CRP • ANA/ENA/dsDNA • SSA/SSB • RF/anti-CCP • ANCA • C3/C4 • Cryoglobulins • AChR Ab • MuSK Ab • AQP4-IgG • MOG-IgG • Anti-ganglioside (GM1, GD1a, GQ1b) • Anti-MAG • GAD65 • NMDA-R • LGI1 • CASPR2 • HIV 4th-gen • Syphilis (RPR/treponemal) • Lyme two-tier • Lipid panel ± ApoB/Lp(a) • Antiphospholipid Ab • Homocysteine • Lead • Mercury • Arsenic • Copper/Ceruloplasmin • Ammonia • CK • Aldolase • tTG-IgA + total IgA • p-tau • Aβ42/40 • NfL

References

• American Academy of Neurology — Practice parameters for evaluation of peripheral neuropathy and cognitive impairment.
• NINDS (NIH) — Neurological diagnostic testing overviews.
• Myasthenia Gravis Foundation of America — Antibody testing guidance.
• National Multiple Sclerosis Society — Diagnostic criteria and mimics.
• Alzheimer’s Association — 2024–2025 updates on blood biomarkers for dementia.
• Infectious Diseases Society of America — Lyme disease and neurosyphilis testing guidance.
• American Heart Association/American Stroke Association — Primary prevention and risk assessment.
• Clinical reviews on neuro-autoantibodies, heavy metals, and vitamin-related neuropathies.

Available Tests & Panels

Your Blood Tests for Neurological Disorders menu is pre-populated in the Ulta Lab Tests system. Use filters to start with a foundational neurology screen, then add neuropathy, autoimmune, infection, toxin, cognitive, or stroke-riskpanels as your situation warrants. Follow collection instructions and review results with your clinician to prioritize imaging and next steps.