Symptoms of de Quervain tenosynovitis include: 
Pain near the base of the thumb
Swelling near the base of the thumb
Difficulty moving the thumb and wrist when doing something that involves grasping or pinching
A "sticking" or "stop-and-go" sensation in the thumb when moving it
 If the condition goes too long without treatment, the pain may spread farther into the thumb or forearm or both. Moving the thumb and wrist may make the pain worse.