Differential Diagnosis for 18-year-old with Syncopal Episode
- Single most likely diagnosis:
- Migraine with aura: The patient's history of a previous migraine, the presence of an aura before the loss of consciousness (LOC), and the subsequent headache and vomiting are all consistent with a migraine episode. The syncopal episode could be related to the migraine, possibly a migrainous syncope.
- Other Likely diagnoses:
- Syncope (vasovagal or cardiac): The episode of LOC followed by vomiting could also suggest a vasovagal syncope, especially if triggered by a specific event or stressor. A cardiac cause, though less likely in a young individual without a known cardiac history, should be considered.
- Seizure (with post-ictal phase): Given the patient's family history of epilepsy and the loss of consciousness, a seizure disorder should be considered, especially if the "aura" described could be interpreted as a seizure aura. The vomiting and headache could be part of a post-ictal phase.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
- Subarachnoid hemorrhage: Although less likely in a young patient without a history of hypertension or known aneurysm, a subarachnoid hemorrhage can present with a sudden, severe headache (often described as "the worst headache of my life") and could lead to LOC and vomiting.
- Intracranial hemorrhage or stroke: Similar to subarachnoid hemorrhage, these conditions are less common in young individuals but can be catastrophic if not promptly diagnosed and treated.
- Cardiac arrhythmias (e.g., long QT syndrome): These conditions can cause syncope and, in some cases, may be associated with a family history of sudden death.
- Rare diagnoses:
- Mitochondrial myopathies: Conditions like MELAS syndrome (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) can present with seizures, headaches, and episodes of LOC, but are rare and typically associated with other systemic symptoms.
- Other channelopathies: Besides long QT syndrome, other channelopathies (e.g., Brugada syndrome) can cause syncope due to arrhythmias but are less common and might not have a clear family history of epilepsy or similar conditions.