Calcium pyrophosphate crystal deposition

Calcium pyrophosphate dihydrate deposition diseaes (CPPD) have been discovered for more than 30 years. Before CPPD crystals were confirmed, they were often called "gout"; after that, they were also called "pseudogout" Because of the calcification of articular cartilage on its X-ray, it is also called "chondrocalcinosi". But this disease can be without cartilage calcification, so it is generally called "pyrophosphate arthropathy".