E72.21

HCC Category Mapping

What This Code Means

Argininemia is a rare genetic disorder where the body cannot properly break down the amino acid arginine, causing it to build up to harmful levels in the blood and urine. This buildup can lead to neurological problems, developmental delays, and other serious health complications.

Coding Tips

• •Argininemia is a metabolic disorder requiring documentation of the specific type and any associated complications (such as hyperammonemia, seizures, or developmental delay) for complete coding
• •This condition is typically lifelong and should be coded as a principal diagnosis when it is the primary reason for the encounter; look for related codes for complications or management of the condition

Clinical Significance

Argininemia (arginase deficiency) is a urea cycle disorder where deficiency of the enzyme arginase causes accumulation of arginine in blood and cerebrospinal fluid. Unlike other urea cycle disorders, argininemia typically presents insidiously in childhood (age 2-4) with progressive spastic diplegia, seizures, and intellectual decline rather than acute hyperammonemic crises. Hyperammonemia when it occurs is usually milder than in other urea cycle disorders.

Documentation Requirements

• ✓Document elevated plasma arginine levels, arginase enzyme activity, genetic testing for ARG1 mutations, neurological assessment including spasticity evaluation, developmental milestones, ammonia levels, and treatment regimen (low-protein diet with essential amino acid supplementation, nitrogen scavenger therapy if needed).
• ✓Record spasticity management plan.

Commonly Confused Codes