A 45-year-old woman comes to the office due to progressive difficulty with night driving and trouble reading road signs and fine print. The patient has systemic lupus erythematosus, which is treated with hydroxychloroquine and prednisone. She avoids sun exposure due to photosensitivity and has vitamin D deficiency for which she takes a vitamin D supplement. Examination shows opacities on the posterior side of the lenses in both eyes. Optic discs are normal. Ocular movements are full. The remainder of the examination shows no abnormalities. Which of the following is the most significant contributing factor for the eye findings in this patient?
Cataracts | |
Pathogenesis |
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Risk factors |
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Clinical features |
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Treatment |
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This patient has bilateral opacities in the ocular lenses, findings consistent with cataracts. Cataracts can cause difficulty with reading and fine visual tasks; patients often see excessive glare at night and halos around bright lights due to light scattering in the lens. Examination findings include white or gray cloudiness of the lens, decreased visualization of retinal detail, and loss of the red reflex.
Cataracts are generally related to chronic photooxidative injury; the prevalence increases with age, and most patients with cataracts first develop symptoms at age >60. However, cataracts can develop earlier in individuals, such as this patient, with exposure to systemic or ophthalmic glucocorticoids (eg, prednisone). This may be due to glucocorticoid-induced transcription of genes in the lens epithelial cell that may alter lens homeostasis or increase the susceptibility to oxidative injury. Other causes of premature cataract formation include diabetes mellitus, ocular trauma, and external radiation exposure.
(Choices A and D) The increased risk of premature cataract formation in patients with systemic lupus erythematosus (SLE) is due primarily to chronic/frequent glucocorticoid exposure, not to the disease itself. Patients with SLE are often treated with hydroxychloroquine; long-term use can cause retinopathy, which presents with decreased central visual acuity, photopsia (flashing lights), and central macular degeneration.
(Choice B) Excessive, not limited, lifetime sun exposure is associated with an increased risk of cataracts.
(Choice E) Common manifestations of vitamin D deficiency include hypocalcemia, bone pain, and accelerated bone loss. Cataracts are not a major consequence of vitamin D deficiency.
Educational objective:
Cataracts are related primarily to chronic photooxidative injury. Most patients with cataracts first develop symptoms at age >60 but exposure to systemic or ophthalmic glucocorticoids can cause cataracts at an early age. Other causes of premature cataract formation include diabetes mellitus, ocular trauma, and external radiation exposure.