• It is a joint disease caused by the accumulation of calcium pyrophosphate dehydrate (CPPD) crystals in the synovium.
• It is frequently seen in the elderly population.
Conditions associated with CPPD storage disease
* Aging
* Disease-related: Primary hyperparathyroidism, Hemochromatosis, Hypophosphatasia, Hypomagnesemia, Chronic gout, Gitelman syndrome
Epiphyseal dysplasias
Clinical Findings
• In the majority of cases, CPPD accumulation is asymptomatic (asymptomatic chondrocalcinosis).
• Osteoarthritis-like chronic non-inflammatory polyarthritis (pseudoosteoarthritis)
o This form is the most common clinical (symptomatic) picture of the disease.
o Involves different joints (MCP, wrist, shoulder, ankle) than primary osteoarthritis.
• Acute calcium pyrophosphate crystal arthritis (pseudogout)
o It is among the most common causes of acute monoarthritis in the elderly.
o Knee joints are most commonly involved.
Diagnosis
• The presence of calcifications (chondrocalcinosis) in the articular cartilages on direct radiographs is of diagnostic value. Apart from chondrocalcinosis, degenerative changes that mimic osteoarthritis can also be seen in the joint.
• The definitive diagnosis is in joint fluid; CPPD crystals are visualized in a polarized light microscope.
Treatment
• Acute attacks are treated like gout.
• If there is an underlying disease that may cause CPPD arthritis, it should be treated.
• Treatments lowering the uric acid level have no place in chronic treatment.