Confabulation is often a striking early feature, associated with the defect in recent memory, but is less apparent in more chronic cases. The bewildered patient substitutes imaginary or confused fabrications for those he cannot recall and may be so convincing that the physician is deceived into thinking that the patient's mental state is normal. The course, which reflects the underlying cause, is often transient. For those with thiamine deficiency, acute necrotic encephalitis, or other conditions in which hippocampal or diencephalic destruction is irreversible, the prognosis is poor, and prolonged institutional care may be required. However, improvement may occur for as long as 12 to 24 mo after onset, and the patient should not be prematurely institutionalized.
Early treatment includes attention to the thiamine deficiency and adequate hydration.
When prolonged fluid therapy is required, special attention must be given to vitamin and caloric requirements. No specific treatment is helpful. Attacks begin abruptly, and during their onset, total disorientation except for self is combined with a retrograde memory deficit that can extend back for several years. Gradually, the impairments resolve as the attack subsides. Seizures and other focal abnormalities are absent.