Differential Diagnosis for Chronic Dry Eye Symptoms

The patient's symptoms of eye irritation, gritty sensation, burning, and increased light sensitivity, particularly in the afternoon, along with the physical examination findings, suggest a differential diagnosis that can be categorized as follows:

• Single Most Likely Diagnosis
  • Dry Eye Disease (Keratoconjunctivitis Sicca): The patient's symptoms of dryness, irritation, and intermittent blurring of vision, which worsen at the end of the day, are classic for dry eye disease. The presence of punctate epithelial erosions, reduced tear break-up time, and abnormal Schirmer's test support this diagnosis. The patient's history of prolonged screen use, which can reduce tear production and increase evaporation, further supports this diagnosis.
• Other Likely Diagnoses
  • Blepharitis: The patient's symptoms of eye irritation and the presence of pouting Meibomian glands that secrete turbid material when the lids are massaged suggest blepharitis, which can coexist with dry eye disease.
  • Meibomian Gland Dysfunction: The patient's symptoms of dryness and irritation, along with the presence of turbid secretions from the Meibomian glands, suggest Meibomian gland dysfunction, which is a common cause of dry eye disease.
  • Contact Lens-Related Dry Eye: Although the patient does not wear contact lenses, this diagnosis should be considered in patients with dry eye symptoms, especially if they have a history of contact lens use.
• Do Not Miss Diagnoses
  • Sjögren's Syndrome: This autoimmune disorder can cause dry eye disease, and the patient's symptoms of dryness and irritation, along with her history of Graves' disease, suggest the possibility of an underlying autoimmune disorder.
  • Thyroid-Associated Dry Eye: The patient's history of Graves' disease and current treatment with levothyroxine suggest the possibility of thyroid-associated dry eye, which can occur in patients with thyroid disorders.
  • Rheumatoid Arthritis-Associated Dry Eye: The patient's family history of rheumatoid arthritis suggests the possibility of an underlying rheumatologic disorder, which can cause dry eye disease.
• Rare Diagnoses
  • Graft-Versus-Host Disease: This rare condition can cause dry eye disease, especially in patients with a history of bone marrow transplantation or other immunocompromised states.
  • Sarcoidosis: This rare autoimmune disorder can cause dry eye disease, especially in patients with a history of lung or skin involvement.
  • Lacrimal Gland Dysfunction: This rare condition can cause dry eye disease, especially in patients with a history of trauma or surgery to the lacrimal gland.

Each of these diagnoses should be considered in the context of the patient's symptoms, physical examination findings, and medical history to determine the most likely cause of her chronic dry eye symptoms.