Differential Diagnosis for Hypertensive Emergency with Posterior Circulation Infarct

The patient's presentation with hypertensive emergency, posterior circulation infarct, and specific neurological findings such as impaired horizontal gaze, multidirectional nystagmus, and impaired accommodation, suggests a complex underlying condition. The following differential diagnoses are considered:

• Single Most Likely Diagnosis
  • Multiple Sclerosis (MS): The patient's symptoms, including visual disturbances (blurred vision, changes in color vision), sudden loss of vision, and specific neurological findings like impaired horizontal gaze and nystagmus, are consistent with MS, especially given the patient's age and the absence of other systemic symptoms. MS is a demyelinating disease that can present with a wide range of neurological symptoms due to the involvement of various parts of the central nervous system.
• Other Likely Diagnoses
  • Neuromyelitis Optica (NMO): Also known as Devic's disease, NMO is an autoimmune, inflammatory disorder that predominantly affects the optic nerves and spinal cord. The patient's visual symptoms and the presence of nystagmus could suggest NMO, although the lack of clear spinal cord involvement or positive NMO antibodies in the provided history makes this less likely.
  • Acute Disseminated Encephalomyelitis (ADEM): ADEM is a monophasic, demyelinating condition that can present with a variety of neurological symptoms, including visual disturbances, following a viral infection or vaccination. The patient's symptoms and the presence of a hypertensive emergency could be related to ADEM, but the absence of a clear precipitating event or more widespread neurological deficits makes this less likely.
• Do Not Miss Diagnoses
  • Pituitary Apoplexy: Although rare, pituitary apoplexy can present with sudden visual loss, headache, and impaired consciousness, and can be associated with acute hypertension. The absence of headache and significant alterations in consciousness in this patient makes this less likely, but it is a critical diagnosis not to miss due to its potential for severe morbidity and mortality.
  • Cerebral Vasculitis: Vasculitis affecting the cerebral vessels can present with a wide range of neurological symptoms, including visual disturbances and hypertension. The diagnosis is critical due to its potential for severe outcomes, but the lack of systemic symptoms such as fever, weight loss, or specific laboratory findings makes this less likely.
• Rare Diagnoses
  • Bickerstaff's Brainstem Encephalitis: A rare inflammatory condition of the brainstem that can follow a viral infection, presenting with symptoms such as ophthalmoplegia, ataxia, and altered consciousness. The patient's impaired horizontal gaze and nystagmus could suggest brainstem involvement, but the overall clinical picture and the absence of more typical symptoms of Bickerstaff's encephalitis make this a less likely consideration.
  • Leigh Syndrome: A rare genetic disorder affecting the central nervous system, characterized by progressive loss of mental and movement abilities, which can include visual disturbances and nystagmus. The patient's age and the acute presentation make this diagnosis unlikely, but it could be considered in the differential for younger patients or those with a suggestive family history.