**Core Concept**
Aromatic amino aciduria, also known as Hartnup disease, is a rare genetic disorder characterized by an inability to properly absorb certain amino acids from the diet, leading to excessive excretion in the urine. This condition is caused by mutations in the SLC6A19 gene, which codes for a transporter responsible for the reabsorption of neutral amino acids in the kidneys.

**Why the Correct Answer is Right**
The infant in this scenario presents with lectonuria (excessive excretion of amino acids in the urine), seizures, and hypoglycemia, which are classic symptoms of aromatic amino aciduria. The condition results from the impaired reabsorption of aromatic amino acids, such as tryptophan, phenylalanine, and tyrosine, which are essential for various bodily functions. The excessive excretion of these amino acids can lead to a decrease in their availability for protein synthesis and energy production, resulting in hypoglycemia and seizures. The SLC6A19 gene mutation affects the kidneys' ability to reabsorb these amino acids, leading to their accumulation in the urine.

**Why Each Wrong Option is Incorrect**

**Option B:** Phenylketonuria (PKU) is a different genetic disorder caused by mutations in the PAH gene, which codes for the enzyme phenylalanine hydroxylase. PKU is characterized by an inability to properly metabolize phenylalanine, leading to its accumulation in the body. While PKU can cause seizures and developmental delays, it is not associated with lectonuria.

**Option C:** Intrauterine infections, such as maternal rubella or cytomegalovirus, can cause a range of congenital abnormalities, including seizures and developmental delays. However, they are not typically associated with lectonuria.

**Option D:** Tyrosinemia is a genetic disorder caused by mutations in the FAH gene, which codes for the enzyme fumarylacetoacetate hydrolase. Tyrosinemia leads to the accumulation of toxic compounds in the body, which can cause liver damage and other systemic problems. While tyrosinemia can cause hypoglycemia and seizures, it is not typically associated with lectonuria.

**Clinical Pearl / High-Yield Fact**
Aromatic amino aciduria is a rare but important diagnosis to consider in infants with seizures and hypoglycemia. It highlights the importance of urine amino acid screening in newborns to detect genetic disorders that may require early intervention.