An 18-year-old presents to her pediatrician complaining of 3 months of conjunctivitis, stiffness in her joints on waking that improves with movement, and slight puffiness of one finger on her right hand. Two years ago, she developed psoriasis on her scalp, chest, nails, and hands after a respiratory infection; it is being managed — with varying degrees of success — with sun exposure, moisturizers, and topical medications. She has a family history of psoriasis (mother). Blood work shows a normal erythrocyte sedimentation rate and an elevated serum immunoglobulin A. Her rheumatoid factor is negative.