Innocent Adult-onset type II citrullinemia complicating pregnancy

Abstract

Type II citrullinemia (CTLN2) is a rare autosomal recessive disorder characterized by hyperammonaemic encephalopathy, resulting from mutations in the SLC25A13 gene. It has age-related clinical manifestations, including neonatal intrahepatic cholestasis and adult-onset presentations. This case report presented a pregnant woman diagnosed with innocent CTLN2. A 22-year-old pregnant woman was diagnosed with CTLN2 after presenting with mental fog, agitation, and elevated ammonia levels. Her pregnancy was terminated, and she subsequently had three more successful pregnancies, during which she was treated with sodium benzoate, L-Arginine, and a protein-poor diet. Her symptoms and liver function tests improved with treatment. This was the first case report of a pregnant woman with CTLN2. Timely diagnosis and appropriate management strategies are crucial for both maternal and fetal health in cases of liver disease during pregnancy. CTLN2 should be considered in the differential diagnosis of coma in pregnancy, particularly when elevated liver enzymes and hyperammonaemia are present.

Keywords

• Citrullineamia
• Coma
• L-arginine
• Pregnancy.

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