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Updated: May 18, 2026
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Exploring the Arginine Methylome by Nuclear Magnetic Resonance Spectroscopy
Published on: December 16, 2021
Recurrent unexplained hyperammonemia in an adolescent with arginase deficiency
Yan Zhang1, Yuval E Landau, David T Miller
1Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA. yan1_zhang@urmc.rochester.edu
Clinical Biochemistry
|September 14, 2012
Summary
Adolescent males with arginase deficiency may experience recurrent hyperammonemia. This study found significantly higher ammonia levels in a patient since age 10, indicating a potential worsening of the condition over time.
Area of Science:
- Biochemistry
- Genetics
- Pediatric Medicine
Background:
- Arginase deficiency is a rare genetic disorder leading to hyperammonemia.
- Recurrent hyperammonemia in adolescents with arginase deficiency can be challenging to manage.
- Concerns about ammonia measurement accuracy prompted an investigation into a patient's clinical presentation.
Observation:
- A 14-year-old male with arginase deficiency presented with recurrent hospitalizations for elevated ammonia levels.
- Discrepancies noted between ammonia levels and clinical hyperammonemia symptoms.
- Ammonia levels were analyzed retrospectively, examining pre-analytical and analytical procedures.
Findings:
- Hospitalizations with ammonia levels exceeding twice the normal limit increased significantly after age 10.
- Both overall and peak ammonia levels were significantly higher post-2008 (p < 0.001).
- Statistical analysis confirmed a significant increase in ammonia levels over time.
Implications:
- This case highlights the potential for worsening hyperammonemia in adolescent males with arginase deficiency.
- Findings may offer insights into the natural history of arginase deficiency.
- Improved understanding can aid in the management of similar pediatric patients.
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