Citrin deficiency

Quantitation of plasma amino acids, especially of citrullinc, is the first step in determining the precise enzyme or transport protein defect in patients with a UCD. If the defect involves N-acetyglutamate synthetase (NAGS), CPSI, or OTC, then plasma citrulline concentration will be low. Marked hypercitrullinemia (>2000 pmol/I.) is seen in argininosuccinate synthetase (AS) deficiency, while moderate increases (>200 pmol/L, normal undetectable) are found in argininosuccinate lyase (AL) and citrin deficiencies. In AL deficiency, the presence of argininosuccinic acid and its anhydrides further distinguishes this disorder. 

ARG-1 deficiency is treated by arginine restriction to about 300 mg/day. Patients thus require strict limitation of protein supplemented with essential amino acids. The effectiveness of such treatment is unclear. Patients with ORNT-1 or citrin deficiency are treated with low-protein diets. The use of sodium benzoate or sodium... 

Citrullinemia type 2 (SLC25A13 gene) Citrin deficiency... 

Citrullinemia type 2 (decreased AS acitivity, citrin deficiency) Argininosuccinic aciduria... 

The clinical syndrome of acute neonatal hyper-ammonemic encephalopathy described in the case report represents the classical presentation of a patient with a urea cycle disorder (UCD). It is important to note that this neonatal course represents only the most common and severe presentation of a UCD. This holds true for all the diseases listed in Table 18-1, with the exceptions of arginase (ARG-1) deficiency, which results in progressive spasticity of the lower limbs, and of the mitochondrial membrane transporters citrin and ornithine transporter 1 (ORNT-1). Deficiency of citrin results in adult-onset encephalopathy deficiency of... 

Vitamin P (citrin), VII, 1-50 antithyrotropic effect, X, 102 ascorbic acid and, X, 102 biological assay, VII, 39-42 capillary resistance and, VI, 88, 125 chemical determination, VII, 42-44 deficiency, manifestations of, VII, 12-15... 

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