Probable diagnosis

• New temporal or occipital headache
• Scalp tenderness
• Jaw claudication
• Fever, weight loss, malaise
• Polymyalgia rheumatica symptoms: shoulder or hip girdle pain and morning stiffness
• Transient preceding visual episodes, amaurosis fugax

Causes of CRAO

1. Arteritic occlusion

• Giant cell arteritis: most important cause to identify urgently in older adults with fever or systemic inflammatory features.
• Other vasculitides: SLE, ANCA-associated vasculitis, polyarteritis nodosa, Behçet disease.

2. Non-arteritic embolic or thrombotic occlusion

• Carotid atherosclerotic plaque or stenosis, commonly cholesterol emboli
• Cardioembolism: atrial fibrillation, valvular disease, infective endocarditis, cardiac thrombus
• Aortic arch atheroma
• Diabetes, hypertension, dyslipidemia, smoking
• Hypercoagulable states: antiphospholipid syndrome, malignancy, inherited thrombophilia, myeloproliferative disorders
• Hyperviscosity or hematologic disease: polycythemia, leukemia, sickle-cell disease
• Trauma or iatrogenic causes

Evaluation

Immediate eye assessment

• Visual acuity and visual fields
• Pupillary examination for RAPD
• Dilated fundus examination
• Fundus photography
• OCT: acute inner-retinal edema/thickening
• Fluorescein angiography if needed, but do not delay urgent treatment or transfer

Urgent GCA assessment

• ESR
• CRP
• CBC with platelet count, looking for anemia and thrombocytosis
• Liver function tests can support inflammatory disease assessment

• Temporal artery tenderness, nodularity, reduced pulsation
• Jaw claudication and scalp tenderness
• Headache, constitutional symptoms, polymyalgia symptoms

• Temporal artery ultrasound, where expertise is available
• Temporal artery biopsy, ideally promptly

Stroke and embolic-source work-up

• Urgent brain CT/MRI and vascular imaging as per stroke protocol
• Carotid duplex ultrasound or CTA/MRA head and neck
• ECG and cardiac telemetry for atrial fibrillation
• Echocardiography, especially if cardiac source or endocarditis is suspected
• Blood cultures before antibiotics if febrile and endocarditis is plausible
• Glucose, HbA1c, fasting lipid profile, blood pressure assessment
• In younger patients or atypical presentations: autoimmune, thrombophilia, hyperviscosity, and infectious evaluation as guided by history

Management

If GCA is suspected: do not wait

1. Immediately involve ophthalmology, neurology/stroke team, and rheumatology.
2. Start high-dose systemic glucocorticoids urgently.
   • With established visual loss or threatened fellow-eye vision, common practice is IV methylprednisolone 500 mg to 1 g daily for 3 days, followed by high-dose oral prednisolone.
   • If no visual symptoms, high-dose oral prednisolone is often used, but this patient has visual ischemia, so IV treatment is generally favored.
3. Arrange temporal artery biopsy or vascular ultrasound, but continue treatment regardless of biopsy timing if clinical suspicion remains high.
4. Add bone, gastric, glucose, and infection-risk prophylaxis/monitoring appropriate to steroid therapy.
5. Consider steroid-sparing therapy such as tocilizumab later under rheumatology guidance, but it does not replace emergency corticosteroids.

Acute CRAO treatment

• Immediate transfer to a stroke center for consideration of protocol-based acute intervention.
• There is no established eye treatment reliably restoring vision after CRAO. Current AAO guidance finds insufficient evidence to support routine IV or intra-arterial thrombolysis for CRAO.
• Ocular massage, lowering intraocular pressure with topical therapy/acetazolamide, anterior chamber paracentesis, carbogen, and hyperbaric oxygen have historically been attempted but should not delay stroke assessment or GCA treatment.
• Thrombolysis may be considered only within an appropriate acute-stroke pathway, very early after onset, with specialist assessment of risks and eligibility.

Secondary prevention

• Antiplatelet or anticoagulation according to the identified stroke mechanism
• Treat atrial fibrillation, carotid stenosis, endocarditis, diabetes, hypertension, and dyslipidemia
• High-intensity statin where indicated
• Smoking cessation and vascular risk reduction
• Ophthalmic follow-up for ocular neovascularization and glaucoma

Exam-style conclusion

Clinical interpretation

Probable diagnosis: antiseizure-drug related hematologic and autoimmune toxicity

• Leukopenia, thrombocytopenia, anemia, or true pancytopenia
• Aplastic anemia or marrow suppression
• Hypersensitivity syndrome
• Drug-induced lupus-like syndrome, sometimes with autoantibody positivity
• Liver dysfunction and lymphadenopathy

1. Systemic lupus erythematosus (SLE) with hematologic involvement and possible neuropsychiatric lupus.
2. Hematologic malignancy, myelodysplastic syndrome, aplastic anemia, or marrow infiltration.
3. Infection, including HIV, hepatitis B/C, EBV/CMV, parvovirus B19, tuberculosis, malaria/dengue depending on location, and sepsis.
4. Nutritional deficiency, especially vitamin B12, folate, or copper deficiency.
5. Hypersplenism.
6. If there is definite erosive, long-standing seropositive rheumatoid arthritis with splenomegaly: Felty syndrome or T-cell large granular lymphocytic leukemia. RF positivity alone does not establish this diagnosis.

How the eye findings fit

• Primary open-angle glaucoma, unrelated to the systemic illness
• Steroid-induced ocular hypertension/glaucoma if the patient has used oral, inhaled, topical, periocular, or ocular corticosteroids
• Secondary glaucoma due to uveitis or another inflammatory eye disorder
• Topiramate-related bilateral secondary angle-closure glaucoma, usually acute and accompanied by eye pain, red eyes, blurred vision/haloes, headache, and a sudden rise in intraocular pressure.

Immediate priorities

• Fever, mouth ulcers, sore throat, cough, dysuria, or other infection symptoms
• Active bleeding, petechiae, black stools, or heavy menstrual bleeding
• Severe pallor, breathlessness, dizziness
• Absolute neutrophil count below 500/µL
• Platelet count below 20,000/µL, or bleeding at any platelet count
• Hemoglobin severely reduced or symptomatic
• Eye pain, red eye, rapid visual loss, or headache with haloes
• New seizures, confusion, focal weakness, or altered consciousness

Evaluation

1. Clarify history and medication exposure

• Exact antiseizure drugs, doses, start dates, recent dose changes, adherence, and combination therapy
• Past CBC results, especially before and after each drug was started
• Methotrexate, azathioprine, sulfasalazine, antibiotics, antithyroid drugs, antipsychotics, and herbal medications
• Steroid exposure in any form
• Symptoms of SLE: photosensitivity, malar/discoid rash, oral ulcers, alopecia, arthritis, serositis, Raynaud phenomenon, renal symptoms
• Symptoms of inflammatory arthritis: prolonged morning stiffness, symmetric small-joint synovitis, deformity
• Fever, weight loss, night sweats, recurrent infections, lymph node enlargement, and splenic enlargement
• Seizure type and age at onset. Seizures beginning in childhood are more likely a separate epilepsy disorder than new neuropsychiatric lupus, unless there are features of active systemic autoimmune disease.

2. Confirm and characterize pancytopenia

• Repeat CBC with differential, platelet count, and reticulocyte count
• Peripheral blood smear, urgently reviewed by hematology/pathology
• Liver and kidney function, LDH, bilirubin, haptoglobin, direct antiglobulin test
• Iron studies, ferritin, vitamin B12, folate, copper
• Coagulation profile
• Drug concentrations where relevant, such as phenytoin, valproate, carbamazepine
• Abdominal ultrasound for splenomegaly and liver disease
• Viral/infectious testing guided by history: HIV, hepatitis B/C, EBV/CMV, parvovirus, malaria/dengue, blood cultures if febrile

3. Autoimmune and rheumatology work-up

• ANA by immunofluorescence
• Anti-double-stranded DNA, anti-Sm
• Complement C3/C4
• Urinalysis, urine protein-creatinine ratio, serum creatinine
• Antiphospholipid antibodies if thrombosis, miscarriages, stroke-like episodes, or seizures with a suspected vascular cause
• ESR and CRP
• RF should be quantified, but add anti-CCP antibody, which is more specific for RA
• Consider antihistone antibodies if drug-induced lupus is suspected

4. Neurologic assessment

• Neurology review of seizure diagnosis and current antiseizure regimen
• EEG if current seizure control/type is unclear
• MRI brain with contrast if seizures changed, focal deficits occur, or CNS autoimmune disease, infection, or malignancy is suspected
• Lumbar puncture only when clinically indicated, for example suspected CNS infection/inflammation

5. Ophthalmology evaluation

• Intraocular pressure in both eyes
• Gonioscopy to distinguish open angle from angle closure
• Optic nerve examination and OCT retinal nerve fiber layer
• Automated visual fields
• Slit lamp examination for uveitis
• Medication review, particularly topical/systemic corticosteroids and topiramate

Management approach

A. If antiseizure-drug toxicity is suspected

1. Admit or arrange urgent specialist review if cytopenias are significant.
2. Stop the suspected offending medication only with neurologist direction and use an alternative antiseizure drug selected for the seizure type and blood count profile.
3. Monitor CBC serially until recovery.
4. Manage complications:
   • Broad-spectrum antibiotics urgently for febrile neutropenia
   • Platelet transfusion for severe thrombocytopenia/bleeding according to local protocol
   • Red-cell transfusion for symptomatic or severe anemia
   • Hematology-directed therapy if aplastic anemia or immune cytopenia is confirmed

B. If SLE is confirmed

• Hydroxychloroquine is generally a foundation treatment unless contraindicated, with baseline and scheduled retinal screening.
• Corticosteroids may be used for significant immune cytopenias or active organ disease, but their dose/duration should be minimized because they can raise intraocular pressure and worsen glaucoma.
• Severe refractory immune cytopenias or major neuropsychiatric lupus may need immunosuppression such as mycophenolate, azathioprine, rituximab, cyclophosphamide, or IVIG, selected by specialists and after excluding infection.

C. If true rheumatoid arthritis with Felty syndrome is confirmed

D. Glaucoma management

• Start or adjust pressure-lowering therapy based on glaucoma type and severity.
• Avoid unnecessary corticosteroids and monitor IOP closely if steroids are essential.
• If topiramate-induced angle closure is suspected: urgent cessation of topiramate under medical supervision, cycloplegic and pressure-lowering treatment by ophthalmology. Laser peripheral iridotomy is generally not the primary treatment for this medication-induced mechanism.

Bottom line