What is calcium pyrophosphate dihydrate crystal deposition disease (CPPD, or pseudogout)?

What is calcium pyrophosphate dihydrate crystal deposition disease (CPPD, or pseudogout)?

Calcium pyrophosphate dihydrate crystal deposition disease (CPPD) is a form of arthritis that causes pain, stiffness, tenderness, redness, warmth and swelling (inflammation) in some joints. It usually affects one joint at a time, but sometimes it may affect several joints at once.

The symptoms are similar to the symptoms of other diseases, especially gout (which is why this form of arthritis had the old name of pseudogout – “false gout”). Some symptoms of CPPD may appear to be symptoms of rheumatoid arthritis or osteoarthritis.

CPPD commonly affects the knee or wrist. Less often, it can involve the hips, shoulders, elbows, knuckles, toes or ankles. Rarely it affects the neck and causes neck, shoulder pains, headaches and in some cases fevers. This occurs when the calcium crystals deposit around the dens part of the second cervical vertebra. The condition is called crowned dens syndrome.