J Korean Med Sci.  2012 Aug;27(8):961-964. 10.3346/jkms.2012.27.8.961.

The First Korean Case of Lysinuric Protein Intolerance: Presented with Short Stature and Increased Somnolence

• Ko JM
• Shin CH
• Yang SW
• Seong MW
• Park SS
• Song J

• KMID: 1714212
• DOI: http://doi.org/10.3346/jkms.2012.27.8.961

Abstract

Lysinuric protein intolerance (LPI) is a rare inherited metabolic disease, caused by defective transport of dibasic amino acids. Failure to thrive, hepatosplenomegaly, hematological abnormalities, and hyperammonemic crisis are major clinical features. However, there has been no reported Korean patient with LPI as of yet. We recently encountered a 3.7-yr-old Korean girl with LPI and the diagnosis was confirmed by amino acid analyses and the SLC7A7 gene analysis. Her initial chief complaint was short stature below the 3rd percentile and increased somnolence for several months. Hepatosplenomegaly was noted, as were anemia, leukopenia, elevated levels of ferritin and lactate dehydrogenase, and hyperammonemia. Lysine, arginine, and ornithine levels were low in plasma and high in urine. The patient was a homozygote with a splicing site mutation of IVS4+1G > A in the SLC7A7. With the implementation of a low protein diet, sodium benzoate, citrulline and L-carnitine supplementation, anemia, hyperferritinemia, and hyperammonemia were improved, and normal growth velocity was observed.

Keyword

Lysinuric Protein Intolerance; Amino Acids, Basic; Hyperammonemia; SLC7A7

MeSH Terms

Amino Acid Metabolism, Inborn Errors/complications/diet therapy/*genetics
Antifungal Agents/therapeutic use
Antigens, CD98 Light Chains/genetics
Asian Continental Ancestry Group/*genetics
Carnitine/therapeutic use
Child, Preschool
Citrulline/therapeutic use
Diet, Protein-Restricted
Disorders of Excessive Somnolence/complications/*diagnosis/drug therapy
Female
Growth Disorders/complications/*diagnosis
Homozygote
Humans
Hypercalcemia/complications/*diagnosis
Metabolic Diseases/complications/*diagnosis
Mutation
Nephrocalcinosis/complications/*diagnosis
Republic of Korea
Sequence Analysis, DNA
Sodium Benzoate/therapeutic use
Vitamin B Complex/therapeutic use
Antifungal Agents
Antigens, CD98 Light Chains
Vitamin B Complex
Citrulline
Sodium Benzoate
Carnitine

Figure

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  Fig. 1 Partial genomic DNA sequences of SLC7A7 gene for the patient and her family members were shown. The patient had a homozygous mutation, IVS4+1G > A, which caused mis-splicing and skipping of exon 4. Her parents and younger brother carried this mutation heterozygously.

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