Back to Basics: Chondrocalcinosis & Pseudogout

- Chondrocalcinosis is calcification of cartilage, synovial tissues and tendons

- The most frequent cause of chondrocalcinosis is pseudogout, but it can also be caused by hypercalcemia, arthritis, gout, Wilson's disease, hemochromatosis, hypothyroidism

- Pseudogout is now commonly referred to as Calcium Pyrophosphate Dihydrate Drystal Deposition (ie. CPPD) or Acute Calcium Pyrophosphate crystal arthritis (CPP crystal arthritis) by many rheumatologists

- Can present as acute monoarticular arthritis or chronic arthritis (typically complicates underlying OA)

- Occurs primarily in elderly patients

- CPPD crystals are found incidentally at arthrocentesis in over 40% of patients with OA!

- Synovial fluid will have positive birfringent rhomboid or rod-shaped crystals (think P for "positive" and "pseudo") vs. the negative bifringent rod-dhaped crystals of gout

- Chondrocalcinosis occurs most commonly in the hand and knee (see x-ray in post)

- Treatment of acute pseudogout is similar to treatment of gout (think NSAIDs, acetominophen and opiates at times). Aspiration of joint is both therapeutic and diagnostic.

References

Saadeh, Constantine.  Calcium Pyrophosphate Deposition Disease.  Medscape website.    http://emedicine.medscape.com/article/330936-overview.  Published July 15, 2016.  Accessed August 27, 2017.