A 42-year-old woman with a history of celiac disease (diagnosed 5 years ago, non-adherent to gluten-free diet) presents with progressive muscle weakness, ataxia, and loss of vibration sense in her lower limbs. She reports chronic diarrhea and steatorrhea. Serum lipid panel shows low total cholesterol (120 mg/dL). MRI brain is normal. Which fat-soluble vitamin deficiency best explains her neurological findings?

Explanation

## Clinical Presentation Analysis The key neurological features are: - Progressive ataxia (cerebellar dysfunction) - Muscle weakness - Loss of vibration sense (posterior column dysfunction) - Chronic fat malabsorption (steatorrhea, low cholesterol) This constellation strongly suggests **Vitamin E deficiency** in the setting of celiac disease with malabsorption. ## Vitamin E: Structure and Function **Key Point:** Vitamin E (α-tocopherol) is a lipophilic antioxidant that protects cell membranes and myelin from oxidative damage. It is absorbed with dietary fat and requires normal intestinal absorption. **High-Yield:** Vitamin E deficiency causes a specific neurological syndrome: 1. **Spinocerebellar degeneration** → ataxia, gait disturbance 2. **Posterior column dysfunction** → loss of vibration and proprioception 3. **Peripheral neuropathy** → muscle weakness, hyporeflexia 4. **Retinopathy** (less common in early disease) ## Why Celiac Disease Leads to Vitamin E Deficiency | Feature | Mechanism | |---------|----------| | **Villous atrophy** | Reduced absorptive surface area | | **Steatorrhea** | Impaired fat absorption → fat-soluble vitamin malabsorption | | **Low cholesterol** | Reflects severe fat malabsorption | | **Non-adherence to GFD** | Continued intestinal damage and inflammation | ## Pathophysiology of Neurological Damage 1. Vitamin E depletion in neuronal membranes and myelin 2. Loss of antioxidant protection → lipid peroxidation 3. Selective degeneration of: - Purkinje cells (cerebellum) - Dorsal root ganglia and posterior columns (proprioception) - Anterior horn cells (motor weakness) ## Clinical Pearl **Abetalipoproteinemia** (rare genetic disorder) and **celiac disease** are the two most common causes of vitamin E deficiency in developed countries. The neurological syndrome is **irreversible if prolonged** — early recognition and supplementation are crucial. **Mnemonic:** **VEAL CHOP** = Vitamins A, E, D, K are fat-soluble; Celiac disease causes malabsorption of all four, but **E** causes the most distinctive neurological syndrome (ataxia + posterior column signs).