Argininosuccinic Aciduria

Argininosuccinic aciduria, is an inherited disorder that causes the accumulation of argininosuccinic acid (also known as “ASA”) in the blood and urine. Some patients may also have an elevation of ammonia, a toxic chemical, which can affect the nervous system. Argininosuccinic aciduria may become evident in the first few days of life because of high blood ammonia, or later in life presenting with “sparse” or “brittle” hair, developmental delay, and tremors.
An infant with argininosuccinic aciduria may seem lethargic or be unwilling to eat, have poorly controlled breathing rate or body temperature, experience seizures or unusual body movements, or go into a coma. Complications from argininosuccinic aciduria may include developmental delay and mental retardation. Progressive liver damage, skin lesions, and brittle hair may also be seen. Immediate treatment and lifelong management (following a strict diet and using appropriate supplements) may prevent many of these complications.
Occasionally, an individual may inherit a mild form of the disorder in which ammonia accumulates in the bloodstream only during periods of illness or other stress.