ICD-10 Code E74.05 – Lysosome-associated membrane protein 2 [LAMP2] deficiency (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E74.05 – Lysosome-associated membrane protein 2 [LAMP2] deficiency
What it is
E74.05 identifies lysosome-associated membrane protein 2 (LAMP2) deficiency, a rare inherited disorder affecting cellular autophagy and lysosomal function. It is often associated with Danon disease and should be coded when documentation specifies LAMP2 deficiency.
Clinical signs
Clinical features vary; refer to documentation. Standard references describe cardiomyopathy, skeletal muscle weakness, and possible cognitive or retinal findings. Confirm the diagnosis is explicitly linked to LAMP2 deficiency rather than a broader metabolic or muscular disorder.
When to use this code
Use E74.05 when the provider documents LAMP2 deficiency, LAMP2-related disease, or Danon disease with this specific molecular diagnosis. It is appropriate for confirmed hereditary cases and for encounters focused on evaluation, monitoring, or family history review tied to the documented condition.
Do not assume the code from nonspecific cardiomyopathy, myopathy, or elevated enzymes alone. You should code only when the record clearly supports LAMP2 deficiency; otherwise, check documentation for the exact diagnosis wording.
Do not use for
Do not use E74.05 for unspecified cardiomyopathy, generic muscular dystrophy, or other lysosomal storage disorders without LAMP2 involvement. If the chart does not name LAMP2 deficiency, check documentation.
Coding tip
Look for the exact genetic or disease term in the assessment, because LAMP2 deficiency is specific and should not be inferred from symptoms alone.