Wednesday, November 14, 2012

Eye allergy, dry eye disease, virus or bacteria - which one is bothering my eyes?


It is a scene that happens every day at our Vancouver eye clinic.  A child comes in with dry eyes.  Simple, right?  Not at all! Here is a window on how doctors distinguish between dry eye disease, bacterial infections, viral infections and eye allergies.

If a child has dry eyes, doctors have to find the cause.  Dry eyes in kids can be caused by allergies, viruses, bacteria or systemic diseases.  A good doctor will correctly determine the cause of the dryness in order to treat the problem effectively.

Doctors distinguish between bacterial and viral infections on the one hand and allergies on the other using many techniques.  One of them is by noting the duration of the episode.   Viral and bacterial infections are usually not chronic.  By contrast, a chronic problem can point to an eye allergy.

Only about 1.5% of healthy children have dry eye disease symptoms and for most children dry eye is the symptom of an eye allergy.  However, parents of children with dry eyes need to take them to the optometrist for evaluation because some symptoms point to potentially serious problems. 

For example, dry eyes with the presence of a symptom such as burning is an indication of possible systemic disease.  In certain children with dry eyes, certain things point to dry eye syndrome such as a history of systemic disease like rheumatoid juvenile arthritis or Sjögren’s syndrome.  Conversely, other things point to allergies such as a history of asthma or atopic dermatitis. Bacteria or a virus may be the cause of dry eyes if the child has a history of recent upper respiratory infection,  or a recent eye infection in a sibling.

Doctors pay close attention to patient symptoms because these help to distinguish between dry eye disease (aka dry eye syndrome) and eye allergy.  Here are some symptoms and the cause that they point to:

  • itching is strongly associated with eye allergy; 
  • burning and foreign body sensation are associated with dry eye disease;
  • complaints of lids matted together, along with irritation and soreness suggest a bacterial infection
  • irritation and pain suggest a virus;
  • sensitivity to light is also usually associated with a virus;
  • tearing eyes are usually a sign of dry eye;