cystathioninuria cys·ta·thi·o·ni·nu·ri·a (sĭs'tə-thī'ə-nē-n&oobreve;r'ē-ə, -ny&oobreve;r'-)
n.
An inherited disorder of cystathionine metabolism characterized by elevated concentrations of cystathionine in the blood, tissues, and urine, and sometimes mental retardation.