Disequilibrium is predominantly a loss of balance. Patients with disequilibrium have the feeling that they are about to fall, specifically without the sensation of spinning. They may appear to sway, and will reach out for something to support them. Disequilibrium can be a component of vertigo, or it may suggest a more specific diagnosis, such as ataxia, which is a lack of coordination when walking.
Atypical causes of dizziness
A positive head impulse test is highly suggestive of a peripheral lesion.
“Light-headedness” may have an element of euphoria or may be indistinguishable from the early part of a syncopal episode. Because other causes of light-headedness can be difficult to distinguish from presyncope, it is important to consider syncope in the differential diagnosis.
The differential of light-headedness can also include panic attack, early hyperventilation, and toxin exposure (such as diphenylarsinic acid,25 pregabalin,26 or paint thinner27).
CORRESPONDENCE Shannon Paul Starr, MD, Louisiana State University Health Sciences Center, 200 W. Esplanade #412, Kenner, LA 70065; sstarr@lsuhsc.edu.
