A 69-year-old woman comes to her physician for evaluation of “gritty,” red, itchy eyes for the past three months. The patient has also had intermittent episodes of associated blurry vision. The patient's visual acuity acutely worsens during periods of reading, driving, and watching television. She reports a past medical history of “
seasonal allergies” and takes oral
antihistamines without relief of symptoms.
Vital signs are within normal limits. Physical examination reveals bilateral
conjunctival injection. Visual acuity testing demonstrates 20/80 vision in both eyes bilaterally. Slit-lamp examination using fluorescein stain reveals “spotty” uptake.
Oral examination reveals multiple
dental caries and halitosis. Laboratory results are demonstrated below:
| Laboratory value | Result |
| Hemoglobin | 11.3 g/dL |
| Hematocrit | 39 % |
| Leukocyte count | 9,100 /mm3 |
| Platelet count | 375,000/mm3 |
| Leukocyte count | 3,000/mm3 |
| Erythrocyte sedimentation rate | 5 mm/h |
| Antinuclear antibodies | Negative |
| Rheumatoid factor | Negative |
| Anti-dsDNA | Negative |
| Anti-Ro/La | Negative |
Which of the following is the most likely etiology of this patient’s clinical condition?
