The involvement of the gastrointestinal system, joints and eyes are commonly in a variety of diseases.
The diseases which primarily affecting the eye and presenting with involvement of joints and gastrointestinal system are uveitis and scleritis
The diseases primarily involving the gastrointestinal system which can affect the eyes are ulcerative colitis
and crohns disease
The diseases primarily involving the joints like rheumatoid arthiritis and other types of arthritis
can involve the eyes.
As your symptoms are basically involving the gastrointestinal system I advice you to undergo investigations in this regard from your physician.