Repetitive Strain Injury (RSI) or Tendinitis: This is a common condition that occurs due to overuse or repetitive movements of the wrist and hand, leading to inflammation of the tendons. The patient's symptoms of wrist, thumb, and finger pain are consistent with this diagnosis, especially if the patient has recently increased their activity level or has a job that involves repetitive hand movements.

Carpal Tunnel Syndrome: This condition occurs when the median nerve, which runs from the forearm into the palm of the hand, becomes pressed or squeezed at the wrist. Symptoms include numbness, tingling, and pain in the hand and wrist, particularly in the thumb, index, and middle fingers.
Osteoarthritis: A degenerative joint disease that can cause pain and stiffness in the joints of the hand and wrist, especially in older adults.
De Quervain's Tenosynovitis: Inflammation of the tendon sheath that surrounds the tendons on the thumb side of the wrist, leading to pain and tenderness, especially when forming a fist, grasping, or turning the wrist.

Ganglion Cyst: A lump or mass that forms under the skin, typically on the wrist, which can cause pain, especially if it presses on a nerve.
Infections (e.g., Cellulitis, Abscess): Bacterial infections of the skin and soft tissues of the hand or wrist, which can cause severe pain, redness, swelling, and warmth.
Fractures or Dislocations: Especially if there was a recent trauma, it's crucial to rule out fractures or dislocations of the wrist or hand bones, as these conditions require immediate medical attention.

Rheumatoid Arthritis: An autoimmune disorder that can cause inflammation and pain in the joints of the hand and wrist, though it typically affects multiple joints and has systemic symptoms.
Gout: A form of arthritis characterized by sudden, severe attacks of pain, swelling, redness, and tenderness, often occurring at the base of the thumb.
Kienböck's Disease: A rare condition where the blood supply to one of the bones in the wrist (the lunate) is interrupted, leading to the bone's death and potential collapse, causing wrist pain.