Systemic polyarteritis nodosa looks creepily/scarily beautiful on PET/CT. Look at that Christmas tree! but sensitivity can be affected by pred, & isn't great even without (48%). By itself, a good rule in test, but not a good rule out test. #ACR24 ABST1962 @MayoClinic @RheumNow https://t.co/y28J6VKja4