First reported case of lysinuric protein intolerance (LPI) in Lithuania, confirmed biochemically and by DNA analysis

We report on an 18-year-old Lithuanian girl with hepatosplenornegaly noticed at birth, which progressed thereafter. The patient had to wait about 17 years for an accurate diagnosis and appropriate therapy. Lactase deficiency, congenital cataract of the right eye, and osteoporosis were observed. Episodes of drowsiness were caused by intake of high-protein food. Laboratory findings included slight hyperammonaernia, high plasma Citr, Ala, Gly, Glu, Ser levels, as well as citrullinuria, lysinuria, glutaminuria, alaninuria, argininuria, prolinuria, hydroxyprolinuria, ornithinuria, and orotic aciduria. Aversion to high-protein diet strongly suggested a disorder resulting in hyperammonaemia. Citrullinaernia was suspected. Subsequently the diagnosis of LPI was made on the basis of biochemical and clinical features. Molecular genetic testing revealed a mutation in the SLC7A 7 gene, confirming the diagnosis.