2023 American Academy of Neurology Abstract Website

Objective:

Vitamin deficiency should be considered during differential diagnosis of neurological symptoms in patients presenting with subacute progressive gait instability and weakness.

Background:

Despite the perception that scurvy is a rare disorder (1,2), clinicians should have a high index of suspicion in patients at risk for nutritional deficiencies including picky eater, behavioral or sensory issues.

Design/Methods:

We report 2 patients of ascorbic acid deficiency who presented with subacute progressive gait instability and weakness.

Results:

Case 1 is a 12-year-old male with autism spectrum disorder who presented with 3 weeks of progressive bilateral lower extremity weakness resulting in wheelchair dependence. Cranial nerves, deep tendon reflexes, and sensory exam were normal. Motor exam notable for proximal > distal lower extremity weakness. Skin and mucosal examination revealed gingival bleeding and corkscrew hair. Detailed dietary history revealed a severely restricted diet. He was found also to have low vitamin D. Patient treated empirically with vitamin C supplementation resulted in marked improvement within 24 hours, so no additional work up was recommended. Ascorbic acid level was extremely low confirming the diagnosis.

Case 2 is a 4-year-old with history of mild hypotonia who presented with subacute progressive lower extremities weakness exacerbated by physical activity. Cranial nerves, deep tendon reflexes, and sensory exam were normal. Motor exam notable for proximal > distal lower extremity weakness, waddling gait, and positive Gowers maneuver. Dietary history revealed restricted diet for the last 3 months. CK normal. Supplementation with Vitamin C resulted in minimal symptoms improvement so additional neuroimaging was recommended such as magnetic resonance imaging (MRI) of brain, spine and thigh/leg as well as lumbar puncture (LP) all unremarkable. Ascorbic acid level was low confirming the diagnosis.

Conclusions:

Dietary restriction and subacute progressive weakness should raise concern for nutritional myopathies. Refusal to bear weight is a frequent presentation of ascorbic acid deficiency (3).