The patient's presentation is consistent with transient global amnesia (TGA), a condition in which transient loss of memory for recent events and difficulty retaining new information occur (anterograde amnesia). Patients are disoriented to place or time, become anxious or upset, and may repeatedly ask questions such as where they are and why they are there. However, self-awareness, language, and motor and social skills are preserved, and neurologic examination is normal. The episode lasts for less than 24 hours (usually 1-10 hours) and may be precipitated by exertion, stress, changes in body temperature, Valsalva maneuver, or recent procedures. The pathophysiology of this condition is unclear. A history of migraines and age >50 are risk factors.
Initial evaluation and management should focus on excluding other diagnoses (eg, toxic/metabolic encephalopathy, stroke, seizures). TGA usually does not recur, and treatment or driving restriction is not required.
Transient ischemic attacks (TIAs) and seizure activity are the main differential diagnostic considerations for patients with TGA. In this patient, however, there are no accompanying symptoms such as speech or motor deficits that are suggestive of TIA and no automatisms such as chewing, lip smacking, or staring that characterize complex partial seizures.
Depersonalization-derealization disorder is marked by the experience of detachment from oneself or one's surroundings rather than memory loss. Dissociative amnesia presents as loss of autobiographical memory. This patient was able to remember details about herself and her family during the episode.