Calcium Pyrophosphate Deposition Disease (CPDD) is defined as a type of arthritis where calcium pyrophosphate dehydrate are deposited within the joint capsule and in the surrounding tissues. This results in destruction of the hyaline cartilage, articular cartilage and fibrocartilage causing a severe form of arthritis and joint deformity. CPDD arthritis, for a long time, has been used interchangeably with gout arthritis. The two conditions are however different.
Causes of Calcium Pyrophosphate Deposition Disease (CPDD)
There is no known cause for CPDD. Studies have found close relationships between certain factors that render an individual susceptible to CPDD. The factors can be categorized into:
- Primary risk factors include:
- Age > 50 years
- Gene mutation in ANKH and COL (responsible for crystal-induced arthritis)
- Women > men
- Secondary risk factors Include:
- Any age <50 years
- Existing metabolic disease e.g. hypothyroidism, hemochromatosis
Symptoms of CPPD
CPDD is characterized mainly by chronic arthritis lasting >12 weeks and gout-like arthritis. It can affect any joint in the body, but the wrist joint, the knee joint and the hip joint are the most common sites of CPPD arthritis.
McCarty classifies the symptoms of CPDD arthritis into 5 major syndromes:
- Asymptomatic arthritis: clinically, there are no symptoms of arthritis. On radiologic imaging, degenerative changes in the joint caps are visualized. In this syndrome of arthritis, established and treating the cause is important in preventing the development of symptoms of arthritis.
- Acute Pseudogout arthritis: makes up 25% of all CPDD cases. Commonly affects one joint (monoarticular arthritis) but can occasionally involve more than one joint (polyarticular arthritis). Complaints such as acute, intense pain with localized swelling in the joint region are common. The joint is also warm, tender to touch and on further evaluation, there’s presence of accumulating fluid in the joint capsule.
- Pseudo-osteoarthritis: is 50% of all CPDD cases. Mainly affects the wrist, elbow, shoulder and knee joints. Spinal joints are not spared. It is often asymmetrical. It specifically causes intense pain in the finger joints severe enough to disable a person from engaging in simple tasks such as holding a glass to drink water.
- Pseudo-rheumatoid arthritis: 50% of CPDD cases exhibit this form of arthritis. The wrist and finger joints are commonly affected. It is classically a polyarticular form of arthritis that is symmetrical. Patients complain of marked morning stiffness lasting more than 30 minutes with some swelling in the affected joints.
- Pseudo-neuropathic arthritis: this accounts for less than 5% of CPDD cases. Very little is understood about this type of arthritis. It tends to be monoarticular, affecting mainly the knee joint. The pain is sharp and intense. Joint mobility is severely compromised causing serious disability in the individual. It is common after the 5th decade of life.
Treatment of AODS
Treatment of CPDD
CPDD is tailored towards reducing symptoms and slowing or terminating the progression of joint destruction. Dr. Burke, a certified board orthopedic surgeon, offers the following treatment plans depending on the clinical manifestations of CPDD arthritis:
- NSAIDs – oral or injections
- Steroids – oral or local intra-articular injections
- Joint aspiration
- Joint replacement