Pseudogout (CPPD)
Acute calcium pyrophosphate crystal arthritis, usually affecting an older person's knee or wrist; confirm the crystal when needed, exclude septic arthritis, and treat the flare without confusing it with urate-driven gout.
Definition
Pseudogout is an acute calcium pyrophosphate crystal arthritis, one clinical manifestation of calcium pyrophosphate deposition disease.
First principles
CPPD is a spectrum, not just one acute attack
Calcium pyrophosphate deposition can be asymptomatic, appear as chondrocalcinosis, cause an acute CPP crystal arthritis attack, or contribute to chronic inflammatory or degenerative joint disease. The term pseudogout is commonly used for the acute attack, but CPPD is the broader and more accurate disease term.
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