MONDO_0016603 (citrullinemia type II) is a severe subtype of citrin deficiency characterized clinically by adult onset (20 and 50 years of age), recurrent episodes of hyperammonemia and associated neuropsychiatric symptoms such as nocturnal delirium, confusion, restlessness, disorientation, drowsiness, memory loss, abnormal behavior (aggression, irritability, and hyperactivity), seizures, and coma. Also known as: CTLN2, adult-onset citrin deficiency, adult-onset type 2 citrullinemia, adult-onset type II citrullinemia, citrullinemia type 2.