SF analysis usually confirms dx, but changes dx 14%. 264 SF samples showed MSU crystals in 89% gout, 9% of CPPD pts. CPP crystals found in 54% of CPPD, 43% of OA & 7% of gout pts. Ca hydroxyapatite seen 1/3 RA, 1/2 OA & 2/3 CPPD https://t.co/B8UkHagXK3 https://t.co/UTncLo6Fyu