Studies of mass infant screening for Wilson disease by urinary ceruloplasmin.

We found a 4-year-old boy in the screened cohort, who showed a low ceruloplasmin (CP) in urine (17 ng/mg-creatinine) and in blood (0.6 mg/dl), but his urine copper was in the normal range. Furthermore this child was diagnosed as Wilson disease (WD) by genetic analysis. Although no significant correlation was observed between urine and blood levels of CP, it is conceivable that WD may be accompanied by very low concentration of urine CP.