G71.032

HCC Category Mapping

What This Code Means

A genetic muscle weakness disorder affecting the hip and shoulder muscles caused by calpain-3 protein dysfunction, inherited in an autosomal recessive pattern requiring two mutated gene copies.

Coding Tips

• •Confirm genetic testing results specifically identifying calpain-3 mutations before coding
• •Document both parents as carriers if family history is available

Clinical Significance

Autosomal recessive limb girdle muscular dystrophy due to calpain-3 dysfunction (LGMD2A/LGMDR1) is one of the most common forms of limb girdle muscular dystrophy. It presents with progressive proximal weakness and elevated creatine kinase, and has specific genetic implications for family counseling. Precise coding enables tracking of this specific genetic subtype and may support eligibility for clinical trials and targeted therapies.

Documentation Requirements

• ✓Genetic testing confirming CAPN3 gene mutation causing calpain-3 deficiency
• ✓Clinical presentation: proximal weakness, elevated creatine kinase
• ✓Muscle biopsy showing reduced or absent calpain-3 on Western blot when available
• ✓Autosomal recessive inheritance pattern documentation
• ✓Functional status assessment: ambulation, respiratory function
• ✓Provider's explicit diagnosis specifying calpain-3 dysfunction

Commonly Confused Codes