Systemic Disease and Ocular Manifestations
Core concepts
Recognize ocular signs of systemic disease: diabetic retinopathy (microaneurysms, hemorrhages, exudates, neovascularization), hypertensive retinopathy (arteriolar narrowing, AV nicking, flame hemorrhages), thyroid eye disease (proptosis, lid retraction, restrictive myopathy), sarcoidosis (granulomatous uveitis, conjunctival nodules), and autoimmune conditions (dry eye in Sjögren syndrome, scleritis in rheumatoid arthritis). Understand the link between systemic medications and ocular effects, such as hydroxychloroquine retinopathy and corticosteroid-induced cataract or glaucoma.
Traps
Questions often ask which systemic condition is most associated with a specific sign. Remember that thyroid eye disease causes lid retraction and proptosis, not ptosis. Hydroxychloroquine toxicity affects the macula (bull's-eye pattern) and requires baseline and periodic screening. Do not confuse diabetic macular edema with exudative AMD; both cause vision loss but differ in etiology and management.
Worked rule of thumb
When a patient presents with bilateral granulomatous uveitis, consider sarcoidosis and order a systemic workup. For patients on hydroxychloroquine, use the 5 mg/kg real-weight dosing rule and schedule annual screening after five years or earlier if risk factors are present.