Arginase deficiency in multiple tissues in argininemia

Area of Science:

• Biochemistry
• Genetics
• Pediatrics

Background:

• Argininemia is a rare autosomal recessive metabolic disorder caused by arginase deficiency.
• It leads to hyperargininemia, a condition characterized by elevated arginine levels in the blood.
• This disorder is associated with severe neurological impairment and developmental deficits.

Observation:

• A young Mexican female presented with severe growth retardation, microcephaly, and neurological symptoms.
• Elevated blood and cerebrospinal fluid arginine levels were observed, alongside increased urinary excretion of related amino acids.
• Significantly reduced arginase activity was detected in erythrocytes, liver, and stratum corneum.

Findings:

• The patient exhibited profoundly low arginase activity across multiple tissues, indicating a generalized deficiency.
• Despite therapeutic interventions including oral lysine and erythrocyte transfusions, blood arginine levels remained high.
• No significant clinical improvement was observed following the therapeutic trials.

Implications:

• This case highlights the challenges in managing argininemia, particularly in achieving therapeutic targets for hyperargininemia.
• The findings suggest that current treatment strategies may be insufficient for severe cases of arginase deficiency.
• Further research into novel therapeutic approaches for argininemia is warranted to improve patient outcomes.