A 60-year-old woman complains of dry mouth and a gritty sensation in her eyes. She states it is sometimes difficult to speak for more than a few minutes. There is no history of diabetes mellitus or neurologic disease. The patient is on no medications. On examination, the buccal mucosa appears dry and the salivary glands are enlarged bilaterally. Which of the following is the best next step in evaluation?
A. Lip biopsyThe complaints described are characteristic of Sjögren syndrome, an autoimmune disease with presenting symptoms of dry eyes and dry mouth. The disease is caused by lymphocytic infiltration and destruction of lacrimal and salivary glands. The Schirmer test, which assesses tear production by measuring the amount of wetness on a piece of filter paper placed in the lower eyelid for 5 minutes, is the appropriate screening test. Most patients with Sjögren syndrome produce autoantibodies, particularly anti-Ro (SSA). Lip biopsy is needed only to evaluate uncertain cases, such as when dry mouth occurs without dry eye symptoms. Mumps can cause bilateral parotitis, but would not explain the patient’s complaint of a gritty sensation, which is the most typical symptom of dry eye syndrome. Corticosteroids are reserved for severe vasculitis or other serious complications. Although anxiety (for which a benzodiazepine could be administered) can cause a dry mouth, it would not cause either parotid swelling or dry eyes.