A 41-year-old woman presented with a 6-month history of gradually prog
ressive postural instability and dysarthria associated with cerebellar
and extrapyramidal signs. No Kayser-Fleischer (K-F) rings were observ
ed on biomicroscopic examination of each cornea. The only evidence of
hepatic dysfunction was a modest elevation of alanine-aminotransferase
. The diagnosis of Wilson disease (WD) was based on low serum cerulopl
asmin, abnormal serum copper and urinary copper excretion, and DNA mar
ker segregation analysis. WD should be considered in the presence of c
haracteristic neurologic and laboratory features, regardless of age at
onset, evidence of hepatic dysfunction, or absence of K-F rings.