Citation: Maestri NE, Brusilow SW, Clissold DB, Bassett SS. Long-term treatment of girls with ornithine transcarbamylase deficiency. N Engl J Med. 1996;335(12):855-859. doi:10.1056/NEJM199609193351204.
Purpose: To present the results of the long-term outcome in 32 girls (aged 1 to 17 years) with symptomatic ornithine transcarbamylase (OTC) deficiency who were enrolled in therapeutic trials of nitrogen scavenger compoundsa from 1979 through 1990.
- Standardized intelligence test scoresb were low-average and remained stable for over 80% of the 23 treated girls who were longitudinally tested.
- Survival in treated patients was greater than 90% (29 of 32 patients) at 5 years with maintenance of appropriate weight for height.
- Treated girls under 5 years of age experienced an average of 1 hyperammonemic episode per year, a frequency that declined with increasing age through puberty.
- The results of this study suggest that treatment that reduces the occurrence of hyperammonemic episodes improves survival and preserves remaining cognitive functioning in patients with OTC deficiency.
- The treatment outcome for any individual patient with OTC deficiency is likely due to several factors, including the degree of adherence to the therapeutic regimen and/or low-protein diet, genetic factors, and environmental stressors.
bStandardized intelligence tests included: Cattell Infant Intelligence Test, McCarthy Scales of Children’s Abilities, Slosson Intelligence Test, Stanford–Binet Intelligence Scale (forms LM and IV), Wechsler Preschool and Primary Scale of Intelligence (WPPSI), Wechsler Intelligence Scale for Children-Revised (WISC-R), Wechsler Intelligence Scale for Children-III (WISCIII), and Wechsler Adult Intelligence Scale-Revised (WAIS-R).