Keratoconjunctivitis sicca syndrome, commonly known as dry eye syndrome (DES), is a multifactorial disease of the tears and ocular surface that leads to symptoms of discomfort, blurry vision, and tear film issues. The most common symptoms include ocular redness, irritation, and discharge along with intermittent blurry vision.

Patients will often describe the irritation as burning or a foreign body sensation or a feeling of "sand" or "grit" or "an eyelash" in the eye when nothing is there. Sometimes the symptoms get worse as the day progresses. In addition, patients often report that their vision gets blurry at times, especially after reading or using the computer for more than 10-20 minutes. Tearing is also a common complaint with dry eye patients.

Symptoms:

• Foreign body sensation
• Redness
• Irritation
• Burning
• Tearing
• Eye ache
• Fluctuating vision

DES is more prevalent in elderly patients of both sexes and in postmenopausal women of various etiologies; however, this condition can be seen in patients of varying age and in both sexes. It can be caused by a decrease in the aqueous production of tears, an increase in tear evaporation, or a combination of the two.

Environmental factors can also play a role. Performing activities with a low blink rate, such as reading, watching television, computer work, etc, can exacerbate DES. In addition, eyelid abnormalities such as lagophthalmos (inability to close the eyes all the way), ectropion (turning out of eyelid), blepharitis (inflammation of the eyelid edge), and meibomian gland dysfunction can all contribute to this condition. Patients with a history of contact lens wear or refractive surgery (LASIK or PRK) have a higher risk of developing DES.

Systemic diseases can also be associated with DES. Common systemic associations include:

• Autoimmune disorders – Sjögren syndrome (approximately 10% of patients with dry eye have underlying primary Sjögren), thyroid dysfunction, rheumatoid arthritis, systemic lupus erythematosus, dermatomyositis, lymphoma, sarcoidosis, graft versus host disease
• Infections – Human immunodeficiency virus, Epstein Barr virus, human T-cell lymphotropic virus type 1, hepatitis C

Associated dermatologic conditions include rosacea, mucous membrane pemphigoid, Stevens-Johnson syndrome, and atopy.

Medications may cause DES. Implicated drugs include diuretics, antihistamines, anticholinergics, antidepressants, systemic retinoids, and frequent prescription eye drop use (more than 4 times a day).