Inflammatory Eye Disease - Ocular Graft versus Host Disease
Graft versus Host disease occurs in people who have had a bone marrow transplant. It is caused by lymphocytes (which are one of the white blood cells that are received in the transplant). In patients who have had a bone marrow transplant, the lymphocytes from the donor sometimes attack the body of the person who has received the transplant.
Normally our lymphocytes fight foreign infections and tumours in our body. This is "Graft Versus Host Disease". This commonly affects the skin and the mucous membranes (moist surfaces of our eyes, mouth and gut) and it may affect other organs.
How does Graft versus Host disease affect the eye?
The conjunctiva, or the moist skin overlying the front of the eye, is commonly attacked in Graft versus Host disease. This attack may take two forms. Firstly the eye may become very inflamed, red and sore. Secondly and more commonly, the attack is chronic and gradual. In this case the ability of the eye to produce enough tears to protect itself is reduced. This usually causes the eye to be persistently dry or irritated; especially in dry environments such as an air conditioned room or a smoky room, or on dry hot days. Very rarely the bone marrow transplant may cause damage to the retina, which affects vision. The prednisolone used as treatment for Graft versus Host disease may affect the inside of the eye and may cause a cataract.
How is ocular Graft versus Host disease treated?
If the Graft versus Host disease is severe and particularly if it affects organs other than the eye, then it will require treatment with immunosuppressive medication such as Prednisolone or Cyclosporin. There are specific treatments for the ocular effects of Graft versus Host disease. If the eyes are very inflamed, then topical steroids are used to dampen the inflammation. If the eyes are dry, then long term topical lubricants (eye drops or ointment) are used to replace the tear film. It is also best to avoid environments that are known to be dry or irritating to the eyes, such as air conditioned rooms or planes or smoke filled rooms. If these measures are not enough, then it is possible to have minor surgery to prolong the duration of any drops or tears that happen to be in the eye. Occasionally the use of humidifiers to humidify the air in a room where the patient spends a lot of time will be useful.
What is the long-term outlook?
The inflammation associated with Graft versus Host disease nearly always settles in the long term. Unfortunately the dry eyes usually persist even when the Graft versus Host disease itself has settled. This is because the damage to the conjunctiva (moist skin over the eyes) is often permanent. This means that long term tear replacement is often needed. If you have any questions, don't hesitate to speak to your eye doctor about your problems.