Differential Diagnosis
- Single most likely diagnosis
- Preeclampsia with severe features (including posterior reversible encephalopathy syndrome or eclampsia): The patient's symptoms of severe headache, nausea, vomiting, and brief loss of consciousness, combined with the presence of bilateral frontal lobe edema on CT scan, are highly suggestive of preeclampsia with severe features. The elevated blood pressure, proteinuria, and hyperreflexia further support this diagnosis.
- Other Likely diagnoses
- Migraine with aura: The patient's history of migraines and the presence of a severe frontal headache could suggest a migraine with aura. However, the presence of bilateral frontal lobe edema and other systemic symptoms make preeclampsia more likely.
- Viral or bacterial meningitis: Although the patient's neck is supple and cranial nerves are intact, meningitis could still be considered, especially given the headache and brief loss of consciousness. However, the absence of fever, neck stiffness, and other meningeal signs makes this less likely.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Subarachnoid hemorrhage or other intracranial hemorrhage: Although the CT scan did not show any bleeding, it is essential to consider this diagnosis, especially given the severe headache and brief loss of consciousness. Further imaging or lumbar puncture may be necessary to rule out this diagnosis.
- Status epilepticus or seizure disorder: The patient's brief loss of consciousness could be suggestive of a seizure disorder. Although the patient has no history of seizures, it is crucial to consider this diagnosis, especially given the presence of bilateral frontal lobe edema.
- Rare diagnoses
- Reversible cerebral vasoconstriction syndrome (RCVS): This rare condition could present with severe headache and brief loss of consciousness. However, it is less likely given the patient's pregnancy and the presence of other systemic symptoms suggestive of preeclampsia.
- Cerebral venous sinus thrombosis: This rare condition could present with headache and brief loss of consciousness. However, it is less likely given the patient's lack of risk factors and the presence of other systemic symptoms suggestive of preeclampsia.