What is the provisional diagnosis and management for a gentleman with uncontrolled hyperparathyroidism (HPT) who presents with sudden loss of vision and bilateral optic disc swelling?

Malignant Hypertension with Hypertensive Optic Neuropathy

The provisional diagnosis is hypertensive optic neuropathy (hypertensive retinopathy grade IV) secondary to uncontrolled hypertension, and the most critical immediate examination is blood pressure measurement with urgent assessment for hypertensive emergency.

Provisional Diagnosis

The presentation of sudden bilateral vision loss with bilateral optic disc swelling in a patient with uncontrolled hypertension strongly suggests hypertensive optic neuropathy as part of malignant hypertension. This represents a medical emergency requiring immediate intervention to prevent permanent vision loss and end-organ damage.

While the question mentions "HPT," if this refers to hyperparathyroidism rather than hypertension, this would be an unusual presentation, as hyperparathyroidism typically does not cause acute bilateral optic disc swelling 1, 2. However, given the clinical context of "uncontrolled HPT" with sudden vision loss and bilateral disc swelling, hypertensive crisis is the most likely and immediately life-threatening diagnosis.

Most Important Immediate Examination

Blood pressure measurement is the single most critical examination that must be performed immediately, as this will:

• Confirm hypertensive emergency (typically BP >180/120 mmHg with end-organ damage)
• Guide immediate management decisions
• Establish baseline for treatment monitoring
• Identify need for ICU-level care

Additional urgent assessments should include:

• Neurological examination to assess for hypertensive encephalopathy or stroke 3
• Renal function assessment (creatinine, urinalysis for proteinuria/hematuria)
• Cardiac evaluation for acute coronary syndrome or heart failure

Immediate Management

Urgent antihypertensive therapy must be initiated immediately, with the following approach:

• Admit to intensive care unit for continuous blood pressure monitoring
• Intravenous antihypertensive agents (labetalol, nicardipine, or sodium nitroprusside) to reduce blood pressure gradually—target 25% reduction in first hour, then to 160/100 mmHg over next 2-6 hours 3
• Avoid rapid blood pressure reduction as this can worsen optic nerve and cerebral perfusion, potentially causing ischemic complications
• Ophthalmology consultation for detailed fundoscopic examination and documentation
• Neuroimaging (MRI brain and orbits with contrast) to exclude other causes of bilateral optic disc swelling, particularly if clinical course is atypical 4

Four Possible Fundoscopic Findings in Hypertensive Retinopathy

1. Bilateral optic disc swelling (papilledema) - representing grade IV hypertensive retinopathy with increased intracranial pressure or direct optic nerve ischemia 3

2. Retinal hemorrhages - flame-shaped (superficial) or dot-and-blot (deep) hemorrhages indicating vascular damage from severe hypertension 5

3. Cotton-wool spots - representing focal areas of retinal nerve fiber layer infarction due to arteriolar occlusion 5

4. Arteriovenous nicking and copper/silver wire arterioles - chronic changes indicating longstanding hypertensive vascular damage with arterial wall thickening and venous compression at arteriovenous crossings 5

Critical Differential Considerations

If blood pressure is not severely elevated, alternative diagnoses must be urgently considered:

• Bilateral optic neuritis (particularly NMOSD or MOGAD) - would require urgent MRI orbits and brain with contrast, plus serum AQP4-IgG and MOG-IgG antibody testing 4, 6
• Increased intracranial pressure from other causes - requires neuroimaging to exclude mass lesion, venous sinus thrombosis, or idiopathic intracranial hypertension 3
• Bilateral non-arteritic anterior ischemic optic neuropathy - though simultaneous bilateral presentation is rare 5

Common Pitfalls to Avoid

• Do not delay blood pressure measurement - this is the most critical diagnostic and therapeutic decision point
• Do not reduce blood pressure too rapidly - aim for controlled gradual reduction to prevent watershed infarction of optic nerves and brain
• Do not assume hyperparathyroidism causes acute bilateral optic disc swelling - this is not a typical presentation of parathyroid disease 1, 2
• Do not miss bilateral optic neuritis - if patient is younger or has atypical features, urgent antibody testing and MRI are essential as treatment differs dramatically 4, 6