Table of Contents Author Guidelines Submit a Manuscript
Case Reports in Genetics
Volume 2017, Article ID 1048717, 3 pages
Case Report

Urea Cycle Defects: Early-Onset Disease Associated with A208T Mutation in OTC Gene—Expanding the Clinical Phenotype

1Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
2Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana, Hospital Universitario San Ignacio, Bogotá D.C., Colombia

Correspondence should be addressed to Fernando Suárez-Obando; oc.ude.anairevaj@zeraus.odnanref

Received 15 November 2016; Accepted 17 January 2017; Published 5 February 2017

Academic Editor: Philip D. Cotter

Copyright © 2017 Ana Isabel Sánchez et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Ornithine transcarbamylase deficiency (OMIM: 311250) is the most common disorder of urea cycle disorders, accounting for nearly 50% of all cases. We report a case of a two-month- old male patient, who attends our medical genetics consultation because of low citrulline levels and elevated glutamine to citrulline ratio detected by expanded newborn screening with tandem mass spectrometry. He is an asymptomatic male with a normal physical examination and appropriate neurodevelopmental milestones. The patient has a family history of one older brother who died at 18 months old from severe and sudden hyperammonemia and a maternal aunt who suddenly died at two years old. He had high plasma ammonium concentration and a confirmed OTC mutation (p.A208T). Usually, this mutation causes OTC deficiency of late onset in adult males. However, this report raises awareness about mutations previously described as a late-onset causing disease, which can cause severe hyperammonemia and high risk of dying at an early age.