Updated July 28, 2015.

Definition: CPPD (calcium pyrophosphate deposition disease) is a type of arthritis caused by deposits of calcium phosphate crystals in the joints. CPPD is known by other names including:

• pseudogout (still commonly used)
• calcium pyrophosphate deposition disease
• chondrocalcinosis (calcium deposits in joint spaces)

Calcium deposits found in CPPD can trigger inflammatory arthritis and joint pain. Risk of a CPPD attack greatly increases with age.

According to the American College of Rheumatology, CPPD crystals are present in as many as 50% of people in their 90s, though not everyone will experience symptoms.

CPPD attacks typically affect the knees. CPPD can also affect the:

• ankles
• elbows
• hands
• wrists
• shoulders

Diagnosis and Treatment

CPPD is often a delayed diagnosis since symptoms are similar to and mistaken for other arthritic conditions including osteoarthritis and rheumatoid arthritis. CPPD can also be mistaken as gouty arthritis (gout). However, in gout, the crystal deposits are composed of uric acid, not calcium phosphate. Proper diagnosis depends on analysis of the crystals found in joint fluid obtained from the affected joint. Since CPPD is a different condition than gout, treatment differs. There are some medications that are used to treat both conditions though. Learn more about CPPD in:

• Pseudogout - 10 Things You Should Know

Also Known As: pseudogout, calcium pyrophosphate deposition disease, chondrocalcinosis

Common Misspellings: CPD CPDD COPD

Examples: CPPD (Calcium Pyrophosphate Dihydrate Deposition Disease) is also called pseudogout. The acronym CPPD is sometimes mistaken for COPD (Chronic Obstructive Pulmonary Disease).

<sub>Sources:

Pseudogout, American College of Rheumatology, Updated September 2012.
http://www.rheumatology.org/Practice/Clinical/Patients/Diseases_And_Conditions/Calcium_Pyrophosphate_Deposition_%28CPPD%29_%28formerly_called_Pseudogout%29/

What You Need to Know About Pseudogout. The Cleveland Clinic. 10/17/2014.
http://my.clevelandclinic.org/services/orthopaedics-rheumatology/diseases-conditions/hic-pseudogout</sub>