Master Calcium Pyrophosphate Deposition Disease (CPPD) (Formerly Pseudogout) with Picmonic for Medicine

Calcium pyrophosphate deposition disease (CPPD) is caused by the deposition of calcium pyrophosphate dihydrate crystals in articular cartilage and synovial fluid, which induces an inflammatory response similar to gout.

CPPD commonly presents as acute or chronic arthritis involving large joints, most classically the knee. Other joints such as the wrist, shoulder, and ankle may also be affected.

This disease is more common with age and is typically seen in individuals above the age of 50 years old.

A previous fracture, meniscal tear, or other articular trauma that alters cartilage integrity and promotes calcium pyrophosphate crystal deposition.

A chronic degenerative joint condition that disrupts cartilage metabolism and increases local cartilage matrix turnover, which facilitates calcium pyrophosphate crystal formation.

Systemic disorders such as hemochromatosis, hyperparathyroidism, hypomagnesemia, hypophosphatasia, or hypercalcemia that change mineral homeostasis and raise the likelihood of calcium pyrophosphate crystal deposition.

Under polarized light microscopy, CPPD crystals are positively birefringent, appearing blue when parallel to the axis of the compensator, opposite to gout’s negatively birefringent urate crystals.

CPPD commonly shows calcium pyrophosphate crystals that appear rhomboid-shaped under polarized light. These crystals typically display weak positive birefringence, which helps clinicians distinguish CPPD from gout.

Radiographic imaging often reveals chondrocalcinosis, a linear calcification of articular cartilage or menisci, which is diagnostic of calcium pyrophosphate crystal deposition.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the first-line treatment for acute CPPD flares, helping reduce pain and inflammation.

Colchicine may be used for the treatment of acute attacks or prophylaxis, as it inhibits neutrophil chemotaxis and reduces inflammation caused by crystal deposition.

Intra-articular or systemic corticosteroids are indicated for patients unable to tolerate NSAIDs or colchicine, or for those with severe inflammation unresponsive to first-line agents.